Biomechanics of Cancellous Screw

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Vol 2 | Issue 2 | May – Aug 2016 | page:56-62 | Anand J Thakur

Author: Anand J Thakur [1]

[1] Irla Nursing Home & Polyclinic, 189, Swami Vivekanand Road, Irla,Vileparle, west, Mumbai -400 056, Mumbai

Address of Correspondence
Dr. Anand Thakur
Irla Nursing Home & Polyclinic, 189, Swami Vivekanand Road, Irla,Vileparle, west, Mumbai -400 056, Mumbai
Email: thakurajt@gmail.com

Abstract

Understanding the basics of implant biomechanics is the foundation of orthopaedic surgery and practice. Bone screws are the most commonly used implant in orthopaedic trauma surgery. This article aims to review the biomechanics and the engineering principles of a bone screw and also discuss the various avatars of a bone screw with main focus on the cancellous screws.
Keywords: Cancellous screws, biomechanics, orthopaedic trauma.

Introduction

A bone screw is used for internal fixation more often than any other implant; it serves to hold together two or more objects and to lag i.e. compress two objects together. Though it appears a simple device, a great deal of complex engineering technology has contributed to its current design.  There are two major types of screw: the wood screw and the machine screw. To understand the difference between the types, one should recapitulate Newton’s Third Law of motion: ‘every force has an equal (in magnitude) and opposite (in direction) reaction force’. Once the screw is set, the force pulling the two components together must be generated by an elastic reaction somewhere within the screw or in the material into which it is inserted.  A wood screw has relatively large threads and is usually tapered; it is put into a material with a small pilot hole. The threads of the screw form their own mating threads by compressing the material. The screw is much stiffer than the wood into which it is inserted; the spring or elastic force therefore arises from the deformation of the surrounding material, not the screw. It is this force that draws together the two wooden surfaces held by the screw (Fig.1 A).

A machine screw differs from a wood screw in that it is intended to be placed into a hole in which threads have already been cut by a tool known as a tap. A pilot hole matching the size of the screw core is first drilled and then tapped by a tool that is twisted into the hole, cutting the threads with a sharp edge. In the case of a machine screw placed in metal, the elastic reaction which lends the screw its compressive force comes primarily from the shank of the screw itself. The machine screw, rather than the much larger cross-section of the surrounding metal, deforms plastically (Fig.1-B). A cancellous bone screw is a modified wood-type screw. It is inserted into an untapped pilot hole; the spring reaction comes from the cancellous bone as it is deformed during the thread forming process. A cancellous screw has four functional parts: head, shaft, thread, and tip (Fig.2).

1. The screw head serves as an attachment for the screwdriver. It has a recessed hexagonal socket (Hex head). A hexagonal head driver makes a strong and alignment-sensitive connection with the screw and offers a good lateral guidance that allows ‘blind’ insertion and removal. The driver tip snugly fits in the screw head and is unlikely to slip out or distort the head. Thus the operator knows the inclination of hex screw of which only the head protrudes from the bone because the screwdriver by necessity aligns with screw axis. The torque transmission is independent of axial thrust and thus does not compromise initially unstable reduction of the fracture fragments. The countersink, or the under-surface of the head, is hemispherical which allows the screw to be angulated in all directions within a washer or the screw hole of a plate while maintaining concentric contact between the screw and the side of the plate. Its disadvantage is its prominence when used without a plate. The screw head serves two functions. Firstly and obviously, it provides the means of applying torque (twisting force) to the screw. Secondly, it acts as a stop. As the head comes in contact with the bone surface, the translational motion of the screw stops and the torque transforms to tension in the screw, which in turn induces compression between the two surfaces. Compression develops only after the translational motion of the screw stops.
2. The shaft or shank is the smooth link between the head and the thread. The shaft length is variable and in a cancellous screw it is significant. Screws with long shafts are used as lag screws. The smooth shaft has no purchase in the proximal segment of the pilot hole and ensures compression by lagging. A significant length of the shaft has threads; a screw thread can be visualized as a long inclined plane or a wedge encircling core (root). The core diameter or root diameter represents the narrowest diameter of the screw across the base of the threads. The torsional strength of a screw varies with the cube of its root diameter. Doubling the root diameter of a screw increases the extent of torque that it can withstand by a factor of 8.
3. The standard cancellous screw has a single thread. The pitch is the distance between the adjacent threads (see Fig.2 B). A cortical screw with a fine thread has a small pitch whereas a cancellous screw with a coarse thread has a large pitch. The stronger the bone (cortex), the smaller the pitch; the weaker the bone (cancellous), the larger the pitch. In an AO large fragment cancellous bone screw the pitch typically measures 2.75 mm; this is also expressed as the number of threads per inch (tpi): 9.2 tpi. Outside diameter of a cancellous screw refers to the diameter across the maximum thread width and affects its the pull-out strength. The larger the outside diameter, the greater the resistance to pull-out. Up to a reasonable limit, the larger the size and surface area of the threads that are engaged, the greater the holding power. This explains why most ‘cancellous’ screws have a wide diameter thread.
4. A corkscrew tip is used in cancellous screws where the tip clears pre-drilled hole. The cancellous screw forms its own threads by compressing the thin walled trabecular bone. Thread-forming tip is suitable only for use in a cancellous bone,
The cancellous bone screw is a thread-forming, self-tapping screw. The term ‘self-tapping screw’ refers to a screw which is inserted directly into a pre-drilled hole without first tapping a thread. Self-tapping screw may further be subdivided into thread-forming and thread-cutting screws. The screw thread forms its own mating bone thread by compressing the soft cancellous bone. A tap should not be used to insert a cancellous screw – a cancellous screw inserted in a tapped hole has lower pull-out strength than one inserted in an untapped hole because tapping removes cancellous bone from the hole, and effectively enlarges it (Fig.3).

The amount of bone removed by tapping increases as the density of bone decreases; the mean volume increase is about 25%. When a cancellous screw is to be inserted first through hard cortical it is necessary to tap the cortical bone. Cancellous taps are provided for this reason alone. The smooth shaft of the cancellous bone screw provides the lag effect without the need for over-drilling. This becomes significant in the larger 6.5 mm screws, where a very large hole would need to be drilled in the near cortex to produce a lag effect. Cancellous screws are available as fully and partially threaded screws. A fully threaded cancellous screw is used as a placement screw to fix a bone plate in metaphyseal and epiphyseal regions. A partially threaded cancellous screw is used as a lag screw. Cannulated cancellous screws are useful for exact placement. A cannulated screw is used over a guide wire for precise insertion in metaphyseal or epiphyseal site to eliminate the problem of having to remove and reposition an incorrectly placed screw. A guide wire accurately visualizes the path of the screw. In addition, the guide wire maintains the reduction and controls the fracture fragments. If guide wire position must be changed, it can be done without enlarging the hole and sacrificing holding strength of the bone. Final placement of the screw requires use of cannulated drill, a cannulated tap, and a cannulated screwdriver. Cancellous cannulated screws come in large and small sizes. Large cancellous cannulated screws are used to fix fractures of the femoral neck, femoral condyle and tibial plateau. Small cannulated cancellous screws are employed for fixation of the distal radius, distal humerus, distal and proximal tibia and carpal scaphoid. A larger root diameter as compared to an equivalent non-cannulated screw is needed to accommodate the central bore of a cannulated screw. This effectively decreases the volume of bone between the screw threads and to some extent curtail its holding power. The cannulated screw head has either an internal hexagonal recess to work with a cannulated screwdriver, or an external hexagonal or square head and a cannulated wrench (Fig. 4).

The internal recess design allows use of a slim screwdriver, and permits a spherical outer shape to the screw head. This can be important in screw removal. Bone growing around a screw head with an external hexagonal head makes removal difficult, since bone must be removed to allow engagement of a wrench. If two external hexagonal screw heads touch, they may lock. The advantage of using the external hexagonal head is the strength provided to the coupling with the driving wrench. The round head with an internal recess puts more demand on the screwdriver’s tip. The screwdriver hexagonal tip must be small enough to fit within the recess in the screw head, yet itself must be cannulated, leaving little material in it. In addition, strength of the screw head-shaft junction is important. The internal hexagonal recess removes material from the head. If this recess is too deep, strength may be lost at the head-shaft junction. To maintain the strength, the diameter of the shaft of a cannulated screw is often designed slightly larger than that of a solid screw of comparable size. Since the stiffness of a cylinder in bending is a function of the third power of its radius, a small increase in the outer radius of the shaft will compensate for the cannula. An example of medium-sized screw of comparable dimensions is shown in Fig 5. Cannulation does not appear to be a problem in the larger screws, but in a smaller screw leaving a cannulation large enough for stiff guide wire, may require the shaft diameter to be significantly increased or the screw will be considerably weaker. There is a misconception that a solid screw is stronger than a cannulated screw of equivalent outer thread diameter. The 6.5-mm cannulated screw usually has a slightly larger shaft (root) diameter than its solid 6.5-mm counterpart. A solid 6.5-mm may have a 3.0-mm thread root diameter, while the 6.5-mm counterpart has a root diameter of 4.8-mm. If the cannula is 2 mm in diameter, the area and polar moments of inertia of the cannulated screw would be 102.6 mm and 514.8 mm compared with 27 mm and 81 mm: i.e. 3.8 and 6.4 times greater respectively than those of the solid screw. A cannulated screw must have a larger root diameter than the solid screw to allow room for the cannula. However, this does decrease its holding power, because of smaller thread depth. Clinically cannulated screws appear to function well and have more than adequate holding power. A cannulated screw for cancellous bone should be self-cutting and self–tapping. The screw tip cuts only when rotated clockwise and is blunt when turned counter-clockwise (removal direction). Such a tip is advantageous in percutaneous procedures. After the guide pin is place, the screw is advanced through the soft tissue while turning it in a counter-clockwise direction. The tip doesn’t cut or wind the soft tissues. When cortex is reached, the rotation is reversed to clockwise, allowing it to cut into the bone. Successful insertion of a cancellous screw starts with the drilling of a pilot hole and ends with the screw achieving a firm purchase in the bone. A pilot hole can be drilled with a Kirschner wire, bur or drill bit. A drill bit (twist drill) is normally used. During drilling a small amount of bone is lodged in the drill’s flutes and is removed; in porotic bone such a loss is detrimental. If a K-wire is used in porotic bone to drill a hole, it preserves the precious bone which is not dislodged but compacted around the pilot hole. Heat is generated while drilling. The energy used to drive the drill bit is converted to heat and may cause thermal damage the bone. Kirchner wires produce more heat than a drill bit. As the pin shaft is smooth, there is no way of eliminating the debris which is inevitably compressed against the wall of the hole leading to an increase in friction and higher temperatures. Heat production is directly related to speed and increases markedly above 500 rpm, which is the optimum recommended speed for a pin. Necrosis of osteocytes can be produced in the long bones of rabbits by exposure to 47°C for one minute. While making a pilot hole, it is essential to use saline as a coolant to keep the bone viable. Irrigation with normal saline solution (‘saline’) is effective and should commence simultaneously with drilling as the temperature increases almost instantaneously at the start of the act and much more slowly thereafter. A washer is often used with a cancellous screw to prevent the screw head from burying into the thin cortex overlying the cancellous bone (Fig. 6). The flat side of the washer rests on bone while its countersunk side matches the underside of the screw head.

In the initial phase of insertion the bone threads in the near cortex may easily get distorted as the moment arm of the torque is large and the screw is largely unsupported. Likewise in osteoporotic bone a substantial torque produced by a large screwdriver handle also can easily destroy the bone threads produced by a self-tapping or cancellous screw. If excessive torque is required to insert a self-tapping screw, it should be removed and its flutes be cleaned before reinsertion. A self-tapping screw may be inserted with a powered or hand operated drill machine.

The accuracy of power insertion is better than that of manual insertion. In very hard bone, a STS may be handled similar to a tap during insertion. The heat generated during insertion is independent of the machine speed. The screw is centred and inserted perpendicular to the hole in a plate. When a screw is driven-in off-centre it may jam or bone threads may get damaged. Besides, bending moments may be created which may damage the bone threads and perhaps weaken the screw.  The so-called holding power of the screw depends on several factors like, thread shape, its depth, its angle factor, the number of threads engaged (bone thickness), the size of the hole and the shear strength of bone. In addition, when the screw is implanted in the bone, the tissue reactions and the bone growth also affect the holding strength; in general, the holding power of the screw is proportional to the bone volume between threads, the length of the screw and its triangulation with the plate (Fig. 7). The triangulation principle is used in locked internal fixator plates for head of the humerus and radius head (Fig. 8)

Screw vs Bolt
A screw is an externally threaded headed fastener which is tightened by applying torque to the head, causing it to be threaded into the material it will hold. A bolt is also an externally threaded headed fastener, which is used in conjunction with a nut and is tightened or released only by twisting a nut (Fig. 9). To obtain reliable and repeatable fastener torque the bolt / nut combination should always be tightened by holding the bolt head stationary and turning the nut 8. A further clarification aimed at disambiguation is available 9. Bolts are headed fasteners having external threads that meet an exacting, uniform bolt thread specification such that they can accept a non-tapered nut. Screws are headed, externally threaded fasteners that do not meet the above definition of bolts.

A screw is designed to cut its own thread; it has no need for access from or exposure to the opposite side of the component being fastened to. A bolt is the male part of fastener system designed to be accepted by a pre-equipped nut of exactly the same thread design; it needs access from or exposure to the far side of bone being fixed. Cancellous and cortical screws are unsuitable to be used as bolts; a specific implant is mandatory.

References

1. Cochran G V B 1982 A primer of orthopaedic biomechanics. Churchill Livingstone, New York.
2. Gozna E R, Harrington I J, Evans D C 1982 Biomechanics of musculoskeletal injury. Williams & Wilkins, Baltimore
3. Albright J A, Johnson T R, Saha S 1978 Principles of internal fixation.
4. Tencer AF, Asnis SE, Harrington RM, Chapman JR 1996 Biomechanics of cannulated and noncannulated screws. In Asnis SE., Kyle RF. Eds. Cannulated screw fixation New York Springer-Verlag pp15-40
5. Lastra J J, Benzel E C 2003 Biomechanics of internal fixation In: Vaccaro AR et al Eds. Principles and practice of spine surgery. Mosby, St. Louis pp 43-65
6. Synthes, Switzerland
7. Burkhart KJ, MD, Muelle LP , , Krezdorn D, Appelmann P,. Prommersberger KJ, Sternstein W, Rommens PM, 2007 Stability of Radial Head and Neck Fractures: A Biomechanical Study of Six Fixation Constructs With Consideration of Three Locking Plates J Hand Surg;32A:1569–1575.
8. R. Paul Haight 2012 http://engineerexplains.com Accessed 8 October 2014
9. http://en.wikipedia.org/wiki/Bolt _(fastener)#Bolts_vs._sc.

How to Cite this article: Thakur AJ. Biomechanics of Cancellous Screw. Trauma International May – Aug 2016;2(2):56-62

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Fixation of Inter-condylar Eminence fragment in Bi-condylar Tibial plateau fracture – Technical note

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Vol 2 | Issue 2 | May – Aug 2016 | page:50-52 | RM Chandak

Author: RM Chandak [1]

[1] Chandak Nursing Home Nagpur Maharashtra India.

Address of Correspondence
Dr. RM Chandak
Chandak Nursing Home Nagpur Maharashtra India.
Email: chandakrm@yahoo.com

Abstract

Bicondylar tibia fractures are most of the time associated with a separate tibial eminence fragment. This fragment is wedge shaped and is lodged between the two main condylar fragments. We we apply clamps to the condylar fragments to hold the fracture, this wedge shaped fragment may get dislodged in the joint cause incongruous reduction. This may later cause knee pain and stiffness. It is important to identify these fragments in bicondylar fractures and to try and reduce them using the technique described below. This will avoid the stiffness and help achieve better and early range of movement
Keywords: Tibia eminence fracture, bicondylar tibia fracture.

Introduction

Bi-condylar tibial plateau fractures are serious injuries and difficult to treat more so if associated with inter-condylar eminence fracture.

The goal of treatment is to re-establish Joint stability, alignment, articular Congruity, Giving better functional outcome  We are used to manage bi-condylar fractures with plates and screws at times resulting into flexion deformity and poor outcome due to ejected out eminence area (Fig. 1) Even small amount of dislogment of the fragment leads to pain and stiffness (Fig 2).


Surgical Technique
The surgical technique is basically aimed at preventing the dislodgement of the eminence fracture. In our example a 45 year old male presented with bicondylar proximal tibia fracture (Fig. 3).

CT Scan is essential in such comminuted cases to determine which column needs buttressing (Fig. 4). This will also help in planning of plates and reduction maneuver is according to complexity of fracture. CT also gives us direction and dimension for fixation of inter-condylar eminence area.

For bicondylar tibial fractures, reduction clamps are effective means of achieving reduction and compression however many a times this causes ejection of the tibial eminence fragment (Fig. 5).

Specially a large V shaped fragment easily eject out on compression even if cross K wires have been used for temporariy fixation (Fig 6).

The main crux of this technique is putting in multiple K wires starting from proximal converging towards the intercondylar eminence. The wires may not pass through the the joint. These converging wires not only hold the condylar fragments but also prevent ejection of the interdondylar eminence fragment (Fig. 7).

If the fragment is too unstable and ejects out while putting in the K wires, direct pressure can be applied to the fragment by probe or Dura elevator (Fig. 8).

To begin with two K wires each can be put in both the medial and lateral fragment and these can then be used to joystick the fragments into reduction with the intercondylar fragments (Fig. 9). In case the central fragment is depressed, it will need elevation as first step and then reduction can proceed as above. A palpating probe can be introduced in the joint to assess the reduction by using a separate stab incision (Fig. 9). All fragments should be reduced and held before application of plates (Fig. 10).

The trick is to reduce the intercondylar fragment with relation to both medial and lateral fragment by using joystick wires. Advancing the joystick wires in the intercondylar fragments once the reduction is achieved. Lastly apply the reduction clamps only one the reduction is achieved and is temporarily stabilised by raft wires. At times the intercondylar fragment may be a single large fragment and can be easily reduced. In these cases if the fragment remains reduced after application of compression clamps, there may be no need for fixation of this fragment and raft screws can hold the fragment well (Fig. 11).

However in cases the fragment is comminuted and is unstable after compression, K wires can be left as fixation methods or in case the fragment is large enough a screw can be used to fix the fragment (Fig. 12,13). Occasionally avulsed ACL fragment alone can be fixed with pull out suture in same or sub sequent procedure.

Conclusion

• Anatomical reduction and stabilisation of inter-condylar eminence fracture associated with bi-condylar tibial plateau fracture is necessary for good outcome.
• If the fragment is stable on condylar compression – don’t fix
• Fixation is a must if fragment ejects out with compression.

How to Cite this article: Chandak RM. Fixation of Inter-condylar Eminence fragment in Bi-condylar Tibial plateau fracture – Technical note. Trauma International May – Aug 2016;2(2):50-52.

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Management of Acetabulum Fractures – Basic Principles and Tips and Tricks

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Vol 2 | Issue 2 | May – Aug 2016 | page:20-24 | Atul Patil, Ashok Shyam, Parag K Sancheti

Author: Atul Patil [1], Ashok Shyam [1], Parag K Sancheti [1]

[1] Sancheti Institute for Orthopaedic and Rehabilitation, Pune. Maharashtra, India.

Address of Correspondence
Dr. Ashok Shyam,
Sancheti Institute for Orthopaedic and Rehabilitation, Pune. Maharashtra, India.
E-mail address: drashokshyam@gmail.com

Abstract

Acetabulum fractures require systematic approach for understanding the fracture pattern and also for planning the treatment plan. The fractures have to be correctly identified radiologically and clear definition of fracture patterns should be made before planning. The radiological parameters must be kept in mind in planning of surgical approach and also the fixation method. This may require a long learning curve but these basics have to be kept in mind while dealing with acetabulum fractures. There are new techniques like 3d CT, virtual assessment of the fracture, 3D print modelling of the fractures that may help in complex fractures, but the basic principles remain the same. Advancements in technology simply refines the ways and means of interpretation and implementation of the basic principles. The current article is compilation of experience gathered over a period of time. The entire article emphasizes on the basics of understanding and managing acetabular fractures and also includes important tips and tricks that facilitate the treatment.
Keywords: Acetabulum fractures, surgical management, Letournal and judet.

Introduction

Acetabular fractures are still difficult fractures to manage and are a major challenge to treating orthopaedic surgeon [1]. Pioneering work was done by Letournal and Judet in 1964 [2]. They systematically classified acetabular fractures and developed a logical line of thinking for dealing with these fractures. They improved the understanding of morphology and popularized surgical principles for management of these injuries. Letournal and Judet put forth the two column theory of acetabulum anatomy. They envisioned acetabulum to be made of two columns. Anterior column from below the sacroiliac joint to the ischial tuberosity and posterior column from superior iliac crest to pubic symphysis with both columns attached to the sacrum by thick strut of bone lying above greater sciatic notch and called sciatic buttress [Fig. 1].

Based on these anatomical factors they suggested the first systematic classification of acetabular fractures.2 Although comprehensive classification is necessary for investigational purposes such as prognosis and outcome studies, it is less important in making decisions on individual cases. Every acetabulum fracture case is different, therefore, trying to force square plug in a round hole is  counterproductive. The surgeon must know the basic fracture types, but even more important, he must be able to interpret the radiographs and draw the fracture lines on a dry skeleton. The 3d CT virtual model and 3D print life size models of fractures acetabulum also need the basic understanding of the fracture anatomy and are helpful only when such clear understanding is present. This clarity also helps in selecting the surgical approach. Most of the innovative work was performed by Letournal and Judet and their recommendation is still valid till date [2,3]. Anatomical reduction of the articular fragment and restoration of a congruent and stable hip are the two most important factors in management of acetabular fractures. Fractures reduced to less than 1 mm of articular step have less incidence of posttraumatic hip arthrosis and a better and long lasting functional restoration as compared to fractures reduced with 1 – 3 mm residual articular displacement [4,5].

To meet these goals congruent and stable hip joint, four objectives are to be kept in mind
1. Correct interpretation of the radiographs
2. Identification and understanding the fracture pattern
3. Choosing the appropriate management
4. Striving for best surgical result.

1. Correct interpretation of radiographs-

On the antero-posterior pelvis radiograph, six lines are identified: the ilioischial line, iliopectineal line, the weight bearing dome (sourcil), teardrop, anterior rim (acetabulo-obturator line), and posterior rim (ischioacetabular line) [Fig. 2].

The iliopectineal line represents the anterior column. The ilioischial line is equated with the posterior column but is not actually created by the posterior border of the innominate bone but by the cortex of the quadrilateral surface. Thus fractures that disrupt the quadrilateral plate are seen as discontinuity of the ilioischial line even though these fractures do not disrupt the posterior border. The radiographic roof represents the cranial portion of the acetabular articular surface namely the weight bearing dome of the acetabulum. The lateral limb of the teardrop represents the floor of the cotyloid fossa while the medial limb represents the lateral wall of the obturator canal. Splitting of tear drop is seen when fracture line transverses through these areas. The anterior and posterior rims give some idea about the wall fractures however they are better diagnosed on Judet views.
Obturator view- is taken with injured side up and pelvis tilted 45 degrees. The posterior column and the anterior wall are visualized well (Figure 3a).
Iliac view – taken with pelvis tilted 45 degrees and injured side down. The posterior column and the anterior wall are visualized well (Figure 3b).

2. Identifying and understanding the fracture pattern-

According to Brander and Marsh [6], answers to following eight questions about the radiographic observations are used to determine the acetabular fracture pattern:
A) Is a fracture of the obturator ring present? If the obturator ring is broken then the fracture is either a column type of’ fracture or a T-shaped fracture.
B) Is the ilioischial line disrupted? Disruption of the ilioischial line occurs in fractures involving the posterior column or fractures in the transverse group.
C) Is the iliopectineal line disrupted? Disruption of the iliopectineal line indicates anterior column involvement or one of the transverse-type fractures.
D) Is the iliac wing above the acetabulum fractured? Iliac wing fractures are observed in fractures involving the anterior column, anterior column with posterior hemitransverse or both column fractures.
E) Is the posterior wall fractured? Posterior wall fractures may occur in isolation or in combination with posterior column or transverse fractures.
F) Does the fracture divide acetabulum into front and back halves or front and bottom halves? T type fracture divides pelvis into top and bottom halves while a column type divides pelvis into front and back halves
G) Is the spur sign present? The spur sign is observed exclusively in the both-column fractures. The spur is a strut of bone extending from the sacroiliac joint. Usually, this strut of bone connects to the articular surface of the acetabulum. In the both-column fracture, this connection is disrupted; a fractured piece of bone that resembles a spur remains. The spur sign is best depicted on the obturator oblique view [Fig 4]
H) What is the orientation of major fracture line on CT scan?
According to the answers of these eight questions, the fractures can be classified using Letournal and Judet classification as shown in Table 1

3. Choosing the appropriate management pathway:

Need for surgical intervention can be determined by following two criteria’s
Fracture criteria’s – Unstable hip [the femoral head and acetabulum are non congruent on AP radiograph], Roof arc angle is less than 45°, Intraarticular fragments, Marginal impaction, Unreduced fracture dislocation
Patient factors – Age [>50 yrs think of conservative treatment and later date Total Hip arthroplasty when arthritis develops], Severe co morbidities [ASA grade III or more – Cx], pre existing hip arthritis [Cx and THA later], severe osteopenia, patients with psychiatric disorders, patients with restricted pre injury mobility.
First decide whether radiograph will require surgery, and then assess the patient for feasibility of surgical intervention. If answer to any of the above question is negative the fracture is treated conservatively.
Few Tips in patient assessment –
Morel-Lavalle´lesions contain liquefied hematoma and have been known to be culture positive nearly 30-50% of times. In such cases drain the hematoma and perform delayed surgery.
Complete neurological examination and documentation is necessary especially in posterior dislocation as it is associated with high incidence of sciatic nerve injuries [20%] which if discovered later gives unsatisfactory result to the patient and may lead to legal issues.
In case the surgery is delayed, skeletal traction is essential

4. Striving for best surgical result.

This involves a definite learning curve. Surgical approach is determined based on the fracture classification. There are four main approaches used for acetabular fractures viz.
A. Kocher-Langenbeck: Posterior wall, Posterior column, Transverse, Transverse PW, Posterior column PW, T shaped [Fig 5, 6].
B. Ilioinguinal: Anterior wall, Anterior column, Anterior Posterior Hemitransverse, Both- column fractures, Transverse (rare) [Fig 7].
C. Extensile iliofemoral approach: Both-column fractures, T shaped, Transverse PW, Fractures > 3 weeks involving both columns [Fig 8]
D. Combined: A single approach is always preferred however combined approaches may be needed for more complex fractures involving both columns.

4. Striving for anatomical reduction.

This is by far the most important variable affecting the outcome of acetabular surgery along with severity of initial trauma. It has a long learning curve and this aspect is highlighted by Matta and Merritt in their study of their first 100 acetabular fracture fixation cases [7]. They grouped the surgical reductions chronologically in groups of 20 consecutive patients and clearly established that with increased experience the ability to achieve anatomical reduction improved along with ability to avoid unsatisfactory results.

Tips and pearls for acetabular surgery

§ Keep three points in mind – Avoid Devascularization of Fragments, remove all intra-articular fragments, and try to achieve anatomical reduction.
§ After exposure, open and clean the fracture site and get intraarticular visibility by a wide capsulotomy which will help in assessing the intraarticular reduction. Keep a low throeshold for widening the exposure
§ Special instruments in form of reduction clamps etc must be kept ready and used when necessary to hold reduction and achieve provisional K wire fixation
§ Reduction of the fragments – this will require two things – traction to the femur and opening through the fracture.
-Traction can be applied by a traction table or direct traction via a corkscrew through femoral neck or a hook on greater trochanter might work as well.
– Open the fracture by removing the major piece out of the way and appreciate the impacted fragments. These fragments have to be reduced to achieve best result.
– In cases where there is a major posterior fragment [high transverse and major T – type], a Schantz pin with a T-handle can be introduced into the ischial tuberosity to manipulate the reduction.
§ Provide stable fixation – most reliable fixation is a lag screw compression. Achieve reduction of the fracture fragments and provisionally fix them with K wires. The fragment can be predrilled first, then reduced and held with two 1.6-mm smooth Kirschner wires. Then each wire is then sequentially replaced by lag screws. This method will prevent shift/toggle of the fracture fragment while insertion of the lag screws.
§ It is desirable to have two points of fixation for each fragment, however this may not be possible because of small size although use of mini screws may be considered
§ After this a neutralization plate is applied to augment the fixation. Here one should keep in mind that lag screws should always be placed along the rim of posterior wall fragments, and care should be taken to ensure that the plate buttressing the posterior wall are positioned as lateral as possible. Applying the buttress plate too medially, especially without rim lag-screw fixation, might result in loss of stabilization of the posterior wall
§ Keep in mind two points while fixing the fractures -Avoid over-contouring of the plate, put in more lag screws rather than a bigger plate
§ In cases with bi-columnar fractures the anterior fragment is fixed with lag screw in first stage. While reducing the posterior column sometimes the anterior column screw needs to be backed out to help get the best reduction after which the screw is re-tightened.

A word of caution about the posterior approach:
The sciatic nerve must be identified and protected by knee flexion. Muscle belly of short rotators should be used to protect the nerve while retraction. Sciatic nerve may vary with respect to its relationship with pyriformis but always lies behind the quadratus muscle and is best identified by this relationship.
. Superior gluteal artery and nerve lie in the greater sciatic notch in close relationship with the bone. They can be injured while stripping of the the periosteum and can retract into the pelvis where they can bleed profusely and are difficult to handle.
. Retraction of the hip abductors might be required for visualization of superior acetabulum; however this may cause traction injury to the superior gluteal nerve which supplies the major hip abductors and the gluteus medius and minimus muscles.
Risk of iatrogenic osteonecrosis of the posterior wall fracture fragments is caused by excessive stripping of their soft-tissue attachments. Every attempt should be made to maintain the capsular attachments to these posterior wall fragments.

Recent Advances

Rapid prototyping and 3D printing are fast coming up as refined diagnostic and planning tool for acetabulum fractures [8,9]. These techniques help in visuospatial visualization of fracture fragments and also determine the best approach and fixation methods and implants. Trajectories of the lag screws can be determined on the virtual 3D models and the same can be utilized during surgery. However the role will be limited to more complex fractures and further refinement of the procedure will help in establishing its role in definitive management of acetabular fractures.

References

1. Tile M, Helfet D, Kellam J. Fractures of the Pelvis and Acetabulum. Baltimore. Lippincott Williams & Wilkins; 3rd edition, 2003.
2. Judet R, Judet J, Letournel E. Fractures of the acetabulum: Classification and surgical approaches for open reduction. J Bone Joint Surg. 1964;46A:1615-38.
3. Letournel E. Fractures of the acetabulum. A study of a series of 75 cases. 1961. Clin Orthop Relat Res 1994;(305):5-9.
4. Letournel E, Judet R. Fractures of the acetabulum, 2nd ed. Berlin: Springer-Verlag, 1993.
5. Matta JM. Fractures of the acetabulum: accuracy of reduction and clinical results in patients managed operatively within three weeks after the injury. J Bone Joint Surg Am 1996;78(11):1632-45.
6. Brandser E, Marsh JL. Acetabular fractures: easier classification with a systematic approach. AJR Am J Roentgenol. Nov 1998;171(5):1217-28.
7. Matta JM, Merritt PO: Displaced acetabular fractures, Clin Orthop Relat Res 230:83, 1988.
8. Zeng C, Xing W, Wu Z, Huang H, Huang W. A combination of three-dimensional printing and computer-assisted virtual surgical procedure for preoperative planning of acetabular fracture reduction. Injury. 2016 Oct;47(10):2223-2227.
9. Duncan JM, Nahas S, Akhtar K, Daurka J. The Use of a 3D Printer in Pre-operative Planning for a Patient Requiring Acetabular Reconstructive Surgery. J Orthop Case Rep. 2015 Jan-Mar;5(1):23-5.

How to Cite this article: Patil A, Shyam AK, Sancheti PK. Management of Acetabulum Fractures – Basic Principles and Tips and Tricks. Trauma International May-Aug 2016;2(2):20-24.

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A Unique Modality for treating Open Supracondylar fracture Femur with Bone Loss. (Gustillo Anderson – 3B)

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Vol 2 | Issue 2 | May – Aug 2016 | page:44-49 | Yashwant J Mahale, Vikram V Kadu

Author: Yashwant J Mahale [1], Vikram V Kadu [1].

[1] ACPM Medical College , Dhule – 424001 , Maharashtra India.
[2] Mahale Accident Hospital , Dhule, Maharashtra India.

Address of Correspondence
Dr. Vikram V Kadu
C/O Vilas Shamrao Kadu, Plot no. 20, Kadu House, Barde layout, Katol Road, Nagpur – 440013
Email: vikram1065@gmail.com

Abstract

Background: Various treatment modalities are used for the treatment of GA-3B injury, yet determining the choice of treatment is difficult. We report fifteen such cases, of which twelve were treated with DCS and 950 plate and three with LCP because of minimal bone stock at the distal end (condyles) along with non- vascularised dual ipsilateral fibular strut graft and cancellous bone grafts from iliac crest.
Materials and Methods: We performed this study from 2000 – 2014. We studied Total 1176 cases of supracondylar fracture femur of which 15 were of type GA-3B. The study consisted of eight males and seven females, eleven were right sided and four left sided. Fifteen patients underwent surgery (twelve were treated with DCS and 950 plate, three with LCP plate) with dual ipsilateral fibular strut graft and cancellous bone graft from iliac crest. Thirteen had functional range of movement (avg 0-1170), one had range of movement 0-70o and one had range of movement 0-15o at knee joint. Fractures united in all fifteen patients with average period of union twelve weeks and all returned to previous work. Immediate treatment consisted of debridement, primary closure, proximal tibial skeletal traction and broad spectrum i/v antibiotics. Once the wound was healed, surgery (open reduction internal fixation (ORIF) with plating with ipsilateral dual fibular strut grafts and cancellous graft) was performed.
Result and Conclusion: We performed two-stage surgery in all the cases. First in the form of debridement and skeletal traction and secondly, definitive fixation was carried out. The current study demonstrated that ORIF with (DCS and 950 / LCP) plate with dual ipsilateral non-vascularised fibular strut graft and cancellous bone grafts from iliac crest is a good modality for open supracondylar fracture femur with bone loss with good results and functional range of movement. This is a small study with favorable results. However, it requires large study group to prove this technique beneficial for treating such fractures.
Keywords: GA-3B, bone loss, fibular strut graft, iliac graft, 95 DCS, LCP.

Introduction

Open supracondylar femur fractures are rare complex injuries complicated by bone loss, contamination, compromised soft tissues, and poor host condition. Fractures of the distal part of the femur are difficult to treat and present considerable challenges in management. Severe soft tissue damage, comminution, extension of fracture into knee joint, neurovascular damage and injury to the extensor mechanism lead to unsatisfactory results in many cases whether treated surgically or non-surgically[1]. Complications such as angular deformity, knee stiffness, and non-union persisted after non-operative treatment suggesting surgical intervention as the choice of treatment.  We report 15 such cases treated with ORIF and plate (DCS and 950 / LCP) with ipsilateral dual fibular strut graft and cancellous bone grafts from iliac crest.

Material and Methods

This is a prospective study conducted at ACPM medical college and Mahale accident hospital since 2000 to 2014. Total cases of supracondylar fracture femur were 1176 of which 15 cases had GA-3B injury. We reviewed patients with open supracondylar fracture femur with bone loss. All the clinical notes and radiographs of the patients with GA-3B injury were reviewed and relevant information was obtained. The patients were followed up three monthly until the fracture was united and at one year the patient was assessed radiologically for fracture union and clinically for pain, deformity, work capacity, shortening, infection and whether he has returned to his routine work (Neer knee score). Thirteen patients had functional range of movement at knee joint (avg 0-1170), 1 had 0-70o and 1 had 0-15o, all fractures united well, average period of union twelve weeks, no pain and all returned to activity of daily living.

Surgical technique
It consisted of emergency and definitive treatment. Once the patient was brought to emergency department the patient was first resuscitated and stabilised. The emergency treatment consisted of wound toilet followed by debridement and primary closure. In cases of opening up of the condyles due to inter-condylar extension temporary fixation with two k-wires was performed (six cases). Proximal tibial skeletal traction was applied. Broad spectrum antibiotics were started. Wound was inspected after 48 hrs and culture sensitivity was sent, according to which specific antibiotics were started till the wound has healed (average period – two weeks).

Once the wound was healthy, aspirate from fracture site was sent to culture sensitivity and if found sterile, surgical procedure in the form of ORIF with DCS and 950 plate (twelve patients) or LCP (three patients) along with dual ipsilateral non-vascularised fibular strut graft and cancellous bone grafts from iliac crest was performed. Post-operative care consisted of i/v antibiotics (according to culture sensitivity), long knee brace with hinge and bedside physiotherapy (quadriceps strengthening exercises and ankle exercises started on day 1, knee flexion and extension after suture removal; two weeks). The patient was kept non-weight bearing for six weeks, and partial weight bearing started after six weeks depending upon fracture union. On the basis of radiological union, full-weight bearing was started after twelve weeks. The patients were followed-up at every three months and were assessed according to Neer Knee Score; clinically (pain, work capacity, joint motion, function) and radiologically (fracture union and implant position) upto one year.

Observation and results

Fifteen cases of open supracondylar fracture femur between 28-68 yrs of age (average age being 48 yrs), of which eight were males and seven females, eleven were right and four left sided, eight were labourers, five housewives and two performing sedentary jobs. All had suffered major road traffic accident. Three patients had associated injuries (one had ipsilateral wrist dislocation and ipsilateral tibia fracture, one had ipsilateral hand injury and one had ipsilateral tibia fracture). Twelve patients had laceration on the lateral aspect of thigh and three over anterior aspect damaging the extensor mechanism. Thirteen patients presented on the day of trauma (between 2-10 hrs) whereas two presented late (six weeks old and three months old).

We used 95 DCS in twelve patients and LCP in three patients. Average ROM was 0-117 degrees. Two patients had decreased ROM (one had 0-700 and other had 0-150). These two patients who presented late were treated at another hospital primarily and were reffered to us (one had two cm of shortening and the other had infection with discharging sinus).


We used the neer knee score to assess the results of our study and found that thirteen patients had good results, one had fair result and one showed poor result. Twelve patients underwent (DCS and 950 plate) with ORIF with ipsilateral dual fibular strut graft and cancellous bone grafts from iliac crest except three patients where LCP was used. Fourteen years of follow-up was obtained. All fractures united well with average union time of three months. Thirteen patients had average range of movement 0-117 degrees. One patient had 0-70 degrees with shortening of two cm, and one patient had 0-15 degrees. Thirteen patients had excellent results while one had fair and one poor result. All the patients returned to their routine pre-operative work.

Complications

In our case series, two patients suffered complications post-operatively. One patient had two cm of shortening. The shortening of the patient was missed pre-operatively. Also the fracture being 6 weeks old and associated with ipsilateral tibia fracture and wrist dislocation, the injury to surgery time was prolonged and so the patient landed up with shortening. It is therefore recommended to take appropriate measurements of femur comparing the contra-lateral limb pre-operatively in order to plan the proper line of management and to avoid limb length discrepancy.  One patient had infection with discharging sinus at the operative site. This patient presented to us three months after the injury. He was taking treatment somewhere else where his tibia fracture was treated with interlock nail and debridement for femoral laceration. No primary closure was done and the wound was infected. Appropriate aseptic measures were taken before, during and after the surgery and antibiotics according to culture sensitivity report. The laceration being on anterior aspect of the thigh added to the complication by damaging the extensor mechanism resulting in poor functional range of movement. Therefore, we recommend thorough debridement with primary closure over drain on day one or secondary closure in the form of plastic surgery, with appropriate antibiotic coverage according to culture sensitivity along with skeletal traction.

Discussion

The aim of this study is to find out mechanism of injury, assessment of results of the operative technique and comparison of results with other available studies. The supracondylar region of femur is a junction of the cylindrical and flat bone and thus is weakest part of the distal femur hence it gets burst out with the major RTA. This mechanism of within outside injury leads to fracture fragment being exposed to the external environment. This leads to the fracture fragment being thrown out from the fracture site due to heavy force which leads to bone loss with irregular damage to soft tissues and often damage to quadriceps. The fragment which makes up for the bone loss is generally lost at the accident site. These types of fractures are usually caused by axial load to a flexed knee during major RTA. The fracture being rare and complicated by bone loss, soft tissue injury and contamination, its treatment and surgical management is proving a challenge for orthopaedic surgeons. Infection and stiffness are major complications. Wound toileting and initial debridement with all aseptic precautions plays a vital role in successful outcomes of such fractures. Treatment of such fractures is challenging for orthopaedic surgeons and therefore we aim at; 1) soft tissue healing, 2) bridging bone defect with bone grafts, 3) rigid fixation, 4) achieving limb length, 5) restoring range of movement, 6) pain free limb and 7) returning to pre-injury status.  Various modalities such as amputation, ilizarov and ORIF with plate are available for treating open supracondylar fracture femur with bone loss. Amputation though not a limb salvage procedure, is a single stage procedure and patient gets back to his routine activities with the help of prosthesis earlier. Also the patient is not bed ridden and does not need to undergo multiple surgeries. Limb salvage procedure includes ilizarov and ORIF with plate. In cases of ilizarov fixator, debridement with wound toileting and ilizarov ring fixator with or without bone grafting or docking is required. In cases of ORIF with plate, for soft tissues primary debridement with wound cover or plastic surgery can be done. For fracture, skeletal traction application followed by ilizarov ring fixator or definitive management with implants viz. angle blade plate, condylar buttress plate, LCP, 95 DCS can be used. For bone loss, cortical as well as cancellous bone grafts are required.  With evolvement of science, Ilizarov technique is now currently considered as the treatment modality for such fractures. Though ilizarov fixator can be applied on day one after thorough debridement of wound, multiple surgeries (corticotomy, docking, bone-grafting etc.) are required. These procedures being needed, the patient may undergo mental and financial stress every time during the surgery. The union time is also longer. Moreover, the patient has to carry the ring fixator for a longer period of time, increasing psychological discomfort to the patient and knee stiffness. Neuro-vascular injuries are also known.  In our case series, we did debridement with primary closure for soft tissue along with skeletal traction for fracture. Definitive management for fracture consisted of 95 DCS plate and non-vascularised dual ipsilateral fibular strut graft and iliac cancellous bone grafts to fill the bone defect. As this plate is a strong construct, it gives rigid fixation allowing for early mobilisation of knee post-operatively. Only in cases where bone stock at the distal end of femur was minimal and insertion of condylar screw in the femoral condyles was not possible, we used locking condylar plate with multiple screws in distal fragment. The dynamic condylar screw is the implant engineered by the AO/ASIF group for use in management of distal femoral fractures and subtrocanteric fractures. The dynamic condylar screw has been recommended as the method of choice [2,3,4,5,6] for the treatment of supracondylar and intercondylar femoral fractures. Fixation with DCS and 95o plate provides rigid construct and therefore movements at the knee joint can be initiated early. It provides rigid fixation of the fracture, early mobilisation and weight bearing with functional range of movement with minimal complications.  In cases, where minimal bone stock is left at the distal end of femur (condyles), insertion of 95 DCS is not feasible. In such cases, locking condylar plate can be used. Insertion of multiple screws in the condylar area provides enough stability to start physiotherapy early which is seen in our three cases. Use of dual ipsilateral fibular strut graft helps in achieving the desired length of the limb and also bridges the site of bone defect effectively [7]. Fibular graft of excess length was harvested so that it could be trimmed as necessary. Two struts were placed in a right angle manner (first along the outer cortex of the bone at the defect and second from the proximal shaft to medial condyle (Fig A). The strut was pushed into one of the fracture fragments and the exact length of graft that needed was trimmed. Once the final shaping of the graft was done, the fracture was reduced. Moreover, use of cancellous bone grafts all around the fibular strut graft helps in achieving osteosynthesis at the fracture site. These grafts (fibular strut and iliac cancellous graft) are taken from the ipsilateral side of the fracture so that the disability remains confined to one limb and the contra-lateral limb is normal allowing early post-op ambulation.  Timing of presentation plays a crucial role in functional outcome of these fracture treatment. Results are excellent with functional ROM in early cases, while in cases with late presentation the results are fair to poor. Open supracondylar femur fractures with critical sized bone defects requires diligent surgical timing in order to optimise the host and wound bed (8). Thorough initial debridement and early definitive fixation is required for sterilisation of the wound and achieving functional ROM. Once the patients have recovered from their other injuries and the soft tissue sleeve has revascularized, bone grafting with internal fixation allows for rigid fixation of the femur and offers the biology these fracture patterns require for successful union without infection. When considering open supracondylar fracture of femur, the location of laceration plays an important role. Severe soft tissue damage, comminution, extension of fracture into knee joint (9,10), neurovascular damage and injury to the extensor mechanism lead to unsatisfactory results in many cases whether treated surgically or non-surgically. In our case series, we found that thirteen patients having lacerations on the lateral aspect of the thigh did well post-operatively and gained functional range of movement as compared to the two patients who had lacerations anteriorly damaging the quadriceps.  Though a complex and major surgery, it can be easily performed by a single experienced surgeon. At the same time the different aspects such as long duration of surgery (avg 2.43 hrs), blood loss (avg 840 ml), need for ipsilateral fibular graft and iliac graft and chances of post-op infection needs to be considered. All these factors can be reduced if two operative teams are simultaneously working. First team prepares the fracture site and fixation and the second team prepares the fibular and cancellous graft. In such instance the duration of surgery can be reduced and is possible to complete the surgery within tourniquet time. This would also reduce the blood loss and minimise the duration of the surgery. Other reported technique of doing two staged surgery is also beneficial in which first stage consists of debridement with antibiotic impregnated bone cement as a spacer [11] to bridge the bone defect till the wound heals so that the biofilm is formed around the spacer and the infection is cleared out. Once the wound is healthy, second stage i.e. definitive fixation can be planned by removing the spacer and using bone graft to bridge the defect along with internal fixation. Though this surgery is beneficial in cases of open fractures where chances of infection is high, bone cement spacer if left for longer duration can act as foreign body causing infection. We do not have any personal experience with this technique. Acceptable knee flexion following treatment ranges from 650 (brown et al, 1971) to 1170 (shelbourne et al, 1982). In our study average ROM was 00 – 1170 which compared favourably with the literature. We compared our results with other studies and found that our results were superior to them (Table no 1).

Conclusion

The study has described trends of RTAs managed by emergency department of hospitals in Karachi. Hospital of Karachi experienced a higher burden of RTAs emergencies in the month of Ramadan 2014 as compared with the preceding months of the year. This increase was mostly concentrated among younger ages range from 16-25 years of age. Injuries in city of Karachi are an important public health problem and contribute to major bulk of Emergency facilities. These accidents and the resultant injuries have considerable physical and socioeconomic impacts; therefore, this issue needs to be addressed. By putting into effect laws that enforce road safety measures and helmet usage can prevent these injuries.

References

1. AS Sidhu et al; Management of distal fracture femur -Supracondylar nailing versus open dynamic condylar screw. Pb Journal of Orthopaedics Vol-XII, No.1, 2011
2. Schatzker J. Fractures of the distal femur revisited. Clin Orthop Relat Res 1998; 347: 43-56.
3. Sanders R, Regazzoni P and Reudi TP: Treatment of supracondylar intercondylar fractures of the femur using the dynamic condylar screw. J Orthop Trauma 1989; 3:214-22.
4. Babst R, Rosso R, Marx A et al: Six years’ experience with the Dynamic Condylar Screw in supra and intracondylar femoral fractures. Helv Chir Acta 1991; 57: 821-24.
5. Warmenhoven PG , VanMouriuk JB and Binnendijk B et al: The treatment of the fractures of the distal femur using the dynamic Condylar screw. Med Tijdschr Geneeskd. 1991; 135: 610-13.
6. Shewring DJ and Meggitt BF et al: Fractures of the Distal femoral treated with the AO dynamic Condylar screw. J Bone Joint Surg.1992; 74B: 122-30.
7. LJRamesh, SA Rajkumar, R Rajendra, HP Rajagopal, MS Phaneesha, S Gaurav; Ilizarov ring fixation and fibular strut grafting for C3 distal femoral fractures; Journal of Orthopaedic Surgery 2004;12(1):91–95
8. Dugan TR1, Hubert MG, Siska PA, Pape HC, Tarkin IS. Open supracondylar femur fractures with bone loss in the polytraumatized patient – Timing is everything!
9. Hutson JJ Jr, Zych GA. Treatment of comminuted intraarticular distal femur fractures with limited internal and external tensioned wire fixation. J Orthop Trauma 2000;14:405–13.
10. Marsh JL, Jansen H, Yoong HK, Found EM Jr. Supracondylar fractures of the femur treated by external fixation. J Orthop Trauma 1997;11:405–10.
11. Masquelet’s Technique for Management of Long Bone Defects: From Experiment to Clinical Application. ISSN 2073– -9990 East Cent. Afr. J. surg. (Online).

How to Cite this article: Mahale YJ, Kadu V. A Unique modality for treating Open Supracondylar fracture femur with bone loss. (Gustillo Anderson – 3B). Trauma International May – Aug 2016;2(2):44-49.

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Hip Instability following DHS Fixation Surgery for Unstable Four Part Per-Trochanteric Fracture Femur

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 Volume 2 | Issue 1 | Jan-Apr 2016 | Page 37-41|Yashwant J. Mahale, Vikram V. Kadu, Abhijeet Deshmukh

Author: Yashwant J. Mahale[1], Vikram V. Kadu [1], Abhijeet Deshmukh[1]

[1] ACPM Medical College , Dhule – 424001 , Maharashtra India.
[2] Mahale Accident Hospital , Dhule, Maharashtra India.

Address of Correspondence

Dr. Vikram V Kadu
C/O Vilas Shamrao Kadu, Plot no. 20, Kadu House, Barde layout, Katol Road, Nagpur – 440013
Email: vikram1065@gmail.com

Abstract

Background: In an ageing population, with resultant osteoporosis hip fractures are common indication for per-trochanteric fracture hip repairs. Various modalities of surgical treatment basically emphasis fracture reduction, fracture immobilization, and rehabilitation as a guide to treatment. Subluxation or dislocation following operative treatment of four part unstable per-trochanteric fracture with Sliding Hip Screw is rare and occasional cases have been reported.
Material and Methods: An observational prospective study carried out at tertiary care hospital from Jan 1997 – Dec 2014. Our operative experience of total 510 patients of which 480 underwent DHS fixation surgery for unstable four part per-trochanteric fracture showed 6 cases of instability as subluxation and dislocation.
Results: We report 6 cases out of 480 DHS fixation showing instability in 3 cases and subluxation and dislocation in 3 cases after 6 weeks of follow-up. These patients were offered arthroplasty and the follow-up results were evaluated after 8 months. Among 6 cases, four had instability after six weeks and remaining two developed dislocation after eight months which were associated with infection. 1 patient refused further investigations & treatment, 3 other died with due course of time, 1 lost to follow -up and One patient with infection underwent excision arthroplasty.
Conclusion: Hip instability following DHS fixation surgery for four part Per-trochanteric fracture femur is a rare complication. Cause of this complication could be mechanical factors (excessive collapse, rotational torque) and infection (superficial or deep) may serve as a contributing factor. Diagnosis was done mainly on the basis of clinical examination and investigations such as X-rays, USG and blood tests. Treatment for such complications consists of Hip arthroplasty. These complications can be prevented with the use of TFN or cemented bipolar prosthesis primarily for treating these type of fractures.
Keywords: Intertrochanteric fracture, hip instability, surgical fixation

Introduction

Per-trochanteric (4 Part) fractures of femur are commonest in elderly people. The incidence is expected to increase in the coming years, with an ageing population resulting in a greater number of traumatic injuries in patients with osteoporotic bone.
DHS fixation is gold standard modality for treatment of such fractures. Various implants used for such fractures are 1) DHS Sliding compression screw and plate devices 2) Intra-medullary devices such as TFN and PFN 3) Enders Nail, 4) Bi-axial plate, 5) External fixator 6) Jewett nail and SP nail. Various Complications of DHS implant are as follows: 1) Implant Failure: a) Cut out of screw b) Proximal or distal migration of screw c) Breaking of plate and screws, 2) Uncontrolled Medialisation of distal fragment and collapse at fracture site, 3) AVN with collapse of head , 4) Infection: Superficial or Deep infection [1)]. However, Hip Instability: Subluxation and Dislocation is very rare [2]. We report, six cases of Hip instability following 480 cases of DHS fixation surgeries for unstable four part Inter- trochanteric fracture.

Materials and Methods
This is a prospective study conducted at our hospital since 1997. We reviewed patients with inter-trochanteric fracture femur treated with various implants. We performed 510 surgeries for Pertrochanteric fracture femur with different modalities DHS (n=480), TFN (n=13), Biaxial Plate (n=15), SP nail (n=1), and Enders Nail (n=1). We found six cases who developed hip instability only after DHS fixation. All available clinical notes and X-rays of these patients were studied to get the relevant information. Of the six cases three were male and two female patients, four had right sided fracture and one had left sided fracture, 4 had infection and 2 had mechanical problems, 1 patient refused further investigations & treatment, 3 other died in due course of time due to unrelated disease complications. 1 lost to follow –up and 1 patient with deep infection underwent excision arthroplasty. Radiological findings of these patients are shown in table 1 and 2.

Table 1: Table showing radiological findings at the diagnosis of instability.

Table 1: Table showing radiological findings at the diagnosis of instability.

 

Table 2: Table showing radiological of collapse *Pre-op measurement was done by drawing a straight line from Greater to lesser trochanter n then from the mid point upto the head of femur. * Collapse of the fragment was calculated from lateral blade plate upto the screw that has back-out. * The average collapse in the above mentioned cases was 9 mm which was found to be excessive as compared to the distance of lag screw backout with a mean length 8.8 mm.(11)

Table 2: Table showing radiology of collapse
*Pre-op measurement was done by drawing a straight line from Greater to lesser trochanter n then from the mid point upto the head of femur.
* Collapse of the fragment was calculated from lateral blade plate upto the screw that has back-out.
* The average collapse in the above mentioned cases was 9 mm which was found to be excessive as compared to the distance of lag screw backout with a mean length 8.8 mm.(11)

Case 1:
A 60 yrs old male was admitted to our hospital with history of domestic fall on Right hip. X-Ray Pelvis with both Hips AP View showed four part pertrochanteric fracture of femur (Fig. 1). Patient had previous history of myocardial infarction. He was treated with DHS and 135 degree 5 hole plate. Early post-operative period was uneventful. Immediate Post-operative X-Ray (Fig. 2) showed relatively acceptable valgus fixation , greater trochanter fragment was not fixed . At 6 weeks follow-up, patient complaint of gradual onset deep pain and difficulty in mobilising right hip. There was no history of recent fall, trauma, fever. On examination, limb was shortened, adducted and internally rotated. Patient had no evidence of infection, movements were limited and painful in all direction . X-Ray Pelvis with both Hips AP View (Fig. 3) showed subluxation of hip joint with DHS implant in situ, excessive collapse at fracture site, rotated femoral head, medialisation of shaft with displaced greater trochanter. The dislocation was reduced and abduction brace was given. Routine Blood examination reports WBC counts – 8300 , ESR – 12 , CRP – Non-Reactive. Patient was medically & financially restrained for further management. Hence immobilisation was continued with brace (Fig. 4). Patient died at the end of 3 months at home.

Figure 1: pre-operative X-ray showing IT fracture femur right side

Figure 1: pre-operative X-ray showing IT fracture femur right side

Figure 2: immediate post-operative X-ray showing good, stable fixation

Figure 2: immediate post-operative X-ray showing good, stable fixation

Figure 3: At 6 weeks follow-up, X-ray showed subluxation of hip joint

Figure 3: At 6 weeks follow-up, X-ray showed subluxation of hip joint

Figure 4: fracture reduced and Abduction brace was provided to maintain the reduction

Figure 4: fracture reduced and Abduction brace was provided to maintain the reduction

Case 2:
70 yr old diabetic male referred to our hospital with gradual onset deep pain, difficulty in mobilization since 15 days. He had history of domestic fall on Right hip 8 weeks back. X-Ray right Hip AP View showed four part pertrochanteric fracture of femur. He was treated with DHS and 135 degree 5 hole plate. Immediate Post-operative X-Ray showed stable fixation with DHS implant in situ. Now the patient complained of pain and limp while walking. On examination, limb was shortened, adducted and internally rotated. Patient had infection at operative site and bed sore. Movements were limited and painful in all direction. X-Ray Pelvis with both Hips Ap View showed dislocation of hip joint with DHS implant in situ, excessive collapse at fracture site, rotated femoral head, medialisation of shaft with displaced greater trochanter. Routine Blood examination reports WBC counts – 17,000 , ESR – 88 , CRP – 1:32 (Reactive). Patient was admitted for further investigations and management but Patient developed Septicaemia and diabetic keto-acidosis and died.

Case 3:
70 year old female, known case of hypertension, presented to our hospital with gradual onset deep pain, difficulty in mobilization, discharging sinus from operative site in left hip since last two months. She suffered a domestic fall on Left hip 6 months back. X-Ray left Hip Ap View showed Unstable four part pertrochanteric fracture of femur. She was treated with DHS and 135 degree 5 hole plate. Immediate post -operative X-Ray was satisfactory. Early post-operative period was uneventful. She was mobilised with walker and then full weight bearing at 4 months. After 6 months, She had discharging sinus and limitation of range of movement of left hip for which she was referred to our hospital. On examination, limb was shortened, adducted and internally rotated, local temperature was raised, operative site was discharging pus with granulation tissue. X-Ray left Hip Ap showed dislocation of hip joint with widely displaced greater trochanter and excessive collapse at fracture site with medialisation of distal fragment. Routine Blood examination reports WBC counts – 13,500, ESR – 70, CRP – 1:32 Reactive. Patient was not willing for further treatment and lost to follow up.

Case 4:
70 years old female known hypertensive presented to our hospital with history of domestic fall on Right hip. X-Ray Pelvis with both Hips AP View showed Unstable four part pertrochanteric fracture of femur. She was treated with DHS and 135 degree 5 hole plate. Intra-operatively, femoral head was found to be rotating during reaming and screw insertion. Early post-operative period was uneventful. At 6 weeks follow up Patient presented with gradual onset deep pain and difficulty in mobilising right hip. There was no history of recent fall, trauma, fever, discharging sinus. On examination, patient had no superficial or deep tenderness, movements limited and painful in all direction. X-Ray Rt. hip AP showed dislocated hip with DHS implant in situ, excessive collapse at fracture site, rotated femoral head and medialisation of shaft. Routine Blood examination reports WBC counts – 8300, ESR- 22, CRP – Non-Reactive. Patient was admitted for further management but died due to Cerebrovascular accident.

Case 5:
65 years old male, came to our hospital with history of fall over right hip. X-Ray Pelvis with both Hips AP View showed Unstable four part inter-trochanteric fracture of femur (Fig. 5). He was treated with 135 degree DHS with 5 hole plate. Immediate post – operative X-Ray was satisfactory (Fig. 6). The patient came regularly for follow-up. Weight bearing was started at 6 weeks. At 10 months follow-up, the patient presented with discharging sinus. On examination, limb was shortened, adducted and internally rotated. Patient had superficial and deep tenderness, movements were restricted and painful in all direction. X-Ray Pelvis with both Hips AP View at 10 months showed subluxation of femoral head with DHS implant in situ, excessive collapse at fracture site, rotated femoral head, with subluxation of the femoral head (Fig. 7). Routine Blood examination reports WBC counts – 9,800, ESR – 80, CRP – Reactive (1:32).USG was done which reported collection in proximal thigh with extension into the hip joint S/O Joint effusion. Hip aspirate was done and pus aspirated was sent for culture. Patient underwent implant removal and excision arthroplasty. Intra operatively large amount of pus was found (Fig. 8), which was drained and infected soft tissue debridement was done to remove all infected and nonviable tissue. Pus and infected deep soft tissues were sent for immediate Gram’s stain, culture and antibiotic sensitivity tests and the head was sent for histopathology which confirmed the diagnosis of pyogenic infection. A skeletal traction system through proximal tibia was applied. Two staged Total Hip Replacement was planned but the patient refused due to financial restraints and ended up with excision arthroplasty (Fig. 9).

Figure 5: pre-operative X-ray showing IT fracture femur right side

Figure 5: pre-operative X-ray showing IT
fracture femur right side

Figure 6: immediate post-operative X-ray showing good, stable fixation

Figure 6: immediate post-operative X-ray showing good, stable fixation

Figure 7: At 10 months follow-up, X-ray showed subluxation of hip joint

Figure 7: At 10 months follow-up, X-ray showed subluxation of hip joint

Figure 8: intra-operatively pus was present at the operative site and the head was completely deformed

Figure 8: intra-operatively pus was present at the operative site and the head was completely deformed

Figure 9: At 6 weeks follow-up after excision arthroplasty

Figure 9: At 6 weeks follow-up after excision arthroplasty

Case 6:
55 years old male k/c/o diabetes and hypertension, came to our hospital with history of fall over right hip. X-Ray Pelvis with both Hips AP View showed Unstable four part inter-trochanteric fracture of left femur (Fig. 10). He was treated with 135 degree DHS with 5 hole plate. Immediate post – operative X-Ray was satisfactory (Fig. 11). The patient came regularly for follow-up. At 6 weeks follow-up, the patient presented with discharging sinus. On examination, limb was shortened, adducted and internally rotated. Patient had superficial and deep tenderness, movements were restricted and painful in all direction. X-Ray Pelvis with both Hips AP View at 6 weeks showed subluxation of femoral head left with DHS implant in situ, excessive collapse at fracture site, rotated femoral head, with subluxation of the femoral head (Fig. 12). Routine Blood examination reports WBC counts – 11,800, ESR – 67, CRP – Reactive (1:32). USG was done which reported collection in proximal thigh with extension into the hip joint S/O Joint effusion. Hip aspirate was done and pus aspirated was sent for culture. The hip was reduced. Patient was not willing for further treatment so was treated by giving abduction brace. The patient died with due course of time due to comorbid conditions.

Discussion
Hip subluxation / dislocation is very rare complication after DHS surgery for four part inter-trochanteric fracture. The present series revealed incidence of 1.04% of 480 DHS suegeries performed. On review of literature occasional case reports of hip instability have been reported [1,2,3,4,5]. Our patients did not undergo further management after making diagnosis of instability for various reasons (3 died, 1 lost to follow up, 1 refused for further management, 1 underwent Excision arthroplasty); (see table no. 3). Various etiopathologies of dislocation / subluxation are on the basis of clinical examination, X-ray, Investigations and review of literature. In these cases it appeared that the factors responsible for instability could be mechanical factors but in some cases presence of pyogenic infection states that infection can be a major contributing factor.

Table 3: Patients demographics indicating age, sex, type of fracture, associated injuries, causative factors and fixation used.

Table 3: Patients demographics indicating age, sex, type of fracture, associated injuries, causative factors and fixation used.

Four part per-trochanteric fracture is generally caused by direct fall on the greater trochanter. This direct force as well as the muscular avulsion force leads to the damage of the capsule, surrounding soft tissues and ligaments and also greater and lesser trochanter are separated making the head rotate freely without any attachment left to it. It is well accepted practice of extraction of femoral head during hemi-arthroplasty procedures. While doing DHS we found out that the femoral head undergoes rotational torque atleast three times (during reaming, tapping and screw insertion ) specially when derotation wire is not used. In all the above mentioned cases the derotation wire was not used. This may cause damage to the remaining soft tissue attachments leading to instability. In right-sided fractures, the screw insertion causes the head fragment to rotate clockwise causing the head fragment to rotate into an extended position at the hip joint. Whereas, in left-sided fractures, the screw insertion causes the head to rotate clockwise leading to head and neck fragment into flexion at the hip and extension of the fracture site leading to potentially unstable construct [8], thereby increasing the soft tissue damage.
Lateral wall plays a key role in stabilisation of unstable pertrochanteric fractures by providing buttress for proximal fragment and its deficiency leads to excessive collapse [6], (table no.2) almost complete resorption of neck causing head to be stabilised against most lateral support which may force femoral head out of acetabulum . Therefore, maintaining the integrity should be important objective in all stabilisation procedures. In patients with four part pertrochanteric fracture femur, if there is gross comminution of posterior & medial cortex , in such patients, femoral head may go into retroversion and varus after fixation due to excessive collapse which may lead to posterior & lateral subluxation of head with progressive weight bearing or stress , finally resulting into dislocation of such hip. Thus lateral wall deficiency, excessive collapse, valgus fixation and postero-medial comminution plays a vital role in determining the instability of the femoral head. All the above mentioned factors are seen in our case series. (table no. 1 and 2).
Patient factors such as mental retardation, poor patient compliance, alcoholic patients, infection and neurogenic causes may lead to dislocation [7]
In our study, 3 cases had infection of which 2 had early and 1 late infection. In early stages of acute infection [4] instability of femoral head may be accounted because of destruction of soft tissue, such as capsule, ligaments and spasm of the adductors. In late stages i.e. chronic infection, the head is damaged asymmetrically in addition to above mentioned factors leading to instability [3] as seen in case 5.
This complication has not been reported with SP nail plate, Jewett nail, TFN, Biaxial plate etc. This may be because rotational torque is not required in fixation of fractures with these implants. However, in case of enders nailing 1 case report has been found leading to dislocation which they claimed was because of perforation of the capsule due to migration of nails in the posterior joint capsule(2). And the other case in which internal fixation of femoral neck fracture was done, concluded that possibly some rotation of the proximal fragment was inadvertently caused, when the fracture was reduced, resulting in twisting of capsule previously torn by trauma [1] suggesting that capsular damage also plays a vital role in instability of hip.
Once dislocation develops; clinical examination of patients, and investigations such as X-rays, CBC, ESR, CRP should be carried out to find out the causes. MRI / CT [10] is not advisable due to implant in situ and may not give the desired result. USG may help to show collection followed by aspiration leading to the diagnosis of infection. Hip arthroplasty would be appropriate option for such complications (Partial, Total, Excisional) depending upon the willingness, associated medical co-morbidities and financial status of the patients.
All the 6 cases who suffered complication were treated with DHS. Mechanical problem during fixation of DHS, loss of lateral femoral wall integrity are definite indicator of DHS implant failure with infection playing a major contributing role. With such fractures, role of DHS must be guarded, augmented with trochanteric stabilisation plate or intra medullary fixation such as TFN or cemented bipolar prosthesis should be considered. While reaming, tapping and screw insertion, additional derotation guide wire must always be used. Greater trochanter should be fixed and head should not rotate intra-operatively after fixation.

 

References

1. Melton JT, Yates P, Middleton RG. Dislocation of hip following valgus fixation of unstable peri-trochanteric fractures : A complication. Injury Extra 2006,
2. Iwegbu CG. Dislocation of the hip following Ender nailing. A case report. J Bone Joint Surg [Am] 1981;63:839-41.
3. Munjal S, Krikler SJ. Dislocation of the hip following intertrochanteric fracture. Injury 1995;26(9):645-6.
4. Infective Failure of Internal Fixation for Intertrochanteric Femoral Neck Fracture Presenting as Hip Joint Subluxation: A Case Report Rohit Rambania, c, Helen Ribeeb, Peter Bobakb; J Med Cases 2010;1(2):51-54.
5. Derek Younge, MD, FRCSC; Patrick A. Loisel, MD, FRCSC. A rare case of hip dislocation after internal fixation of femoral neck fracture without infection; JCC, Vol. 40, No1, février 1997.
6. Gotfried Y. The lateral trochanteric wall: a key element in the reconstruction ofunstable pertrochanteric hip fractures. Clin Orthop Relat Res 2004;425:82–86,
7. Mahoney CR, Pellicci PM. Complications in total hip arthroplasty: avoidance and management of dislocations. Instr Course Lect 2003;52;247-55.
8. Mohan R, Karthikeyan R, Sonanis SV.Dynamic hip screw: does side make a difference? Effects of clockwise torque on right and left DHS. Injury. 2000 Nov;31(9):697-9.
9. Speed JS, Knight RA. Postoperative infections following internal fixation for fractures of the hip. Ann Surg 1956;143(5):651-657; discussion, 657-659.
10. Moorman CT 3rd, Warren RF, Hershman EB, et al. Traumatic posterior hip subluxation in American football. J Bone Joint Surg Am 2003;85A(7):1190-1196.
11. T6-10 APOA 2009 Trauma & Infection,Taipei : The Average Distance of Lag Screw Backout in Unstable Intertrochanteric Fracture After DHS Fixation with Trochanteric Stabilizing.

How to Cite this article: Yashwant J. MahaleYJ, KaduVV, Deshmukh A. Hip Instability  Following Dhs Fixation Surgery for Unstable Four Part Per- Trochanteric Fracture Femur. Trauma International Jan-Apr 2016;2(1):37-41.

Dr Yashwant Mahale

Dr Yashwant Mahale

Dr. Vikram V. Kadu

Dr. Vikram V. Kadu

Dr. Abhijeet deshmukh

Dr. Abhijeet deshmukh

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Frequency of Motor Bike Injuries, Helmet Vs Non Helmet Wearing in Karachi Pakistan

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 Volume 2 | Issue 1 | Jan-Apr 2016 | Page 34-36|Ranjeet Kumar, Muhamad Muzamil,  Kashif Mahmood,  Prof Anisuddin Bhatti, Prof Saeedi Minhas, Vinod Kumar

Author: Ranjeet Kumar[1], Muhamad Muzamil[1],  Kashif Mahmood[1],  Prof Anisuddin Bhatti[1], Prof Saeedi Minhas[1], Vinod Kumar[1]

[1]  Department of Orthopedics, Jinnah Post Graduate Medical center, Karachi, Pakistan.

Address of Correspondence

Dr. Ranjeet Kumar
Jinnah Post Graduate Medical center, Karachi, Pakistan.
Email: ranjeetkumartalib@yahoo.com

 

Abstract

Purpose: To assess the frequency of motor bike injuries in Karachi, Pakistan’s largest city, and frequency of helmet and non helmet wearing among motorcyclist.
Design: cross-sectional study.
Place and duration of study: Accident& emergency department of Jinnah Post Graduate Medical Center, Civil hospital, Abbasi Shaheed Hospital, Aga Khan hospital and Liaqat Hospital Karachi. Pakistan from Jan 2014 to December 2014.
Patients and Methods: A descriptive cross-sectional study was carried out by ROAD TRAFFIC INJURY RESEARCH AND PREVENTION CENTRE “RTIR&PC” in the five tertiary care hospitals (Civil Hospital ,Jinnah Postgraduate Medical Center, Abbasi Shaheed Hospital and Aga Khan Hospital) of Karachi, Pakistan. All male motorbike accident victims presented to the emergency department of the selected hospital, were included in the study. A pretested trauma registry form was completed for all patients.
Results: Total numbers of accidents were 24360 and total number of injured were 30274. Minor injury 23825 approximately 78.6%, around 65 per day, serious were 5382 approximately 17%,around 15 per day and fatal were 1067 approximately 3.5%, 3 per day. Bike rider injuries were 25855 approximately 85% of all injuries and fatal bike rider accident were 506 approximately 47% of all fatalities. Helmet wearing bike riders were 1123 approximately 4.3% and non helmet wearing were 16681 approximately 64.5%. Injuries related to body part were , head and neck 23% ,fatal were 53%, face 17% ,fatal were 16%, chest 1% fatal 1%, abdomen, pelvic contents 1% fatal 1%, extremity, pelvic girdle 29% fatal 17% external injuries 28% fatal 12%.
Conclusion: Injuries in city of Karachi are an important public health problem and contribute to major bulk of Emergency facilities. Motorbike riders are known to be more vulnerable to road accidents and became victims of severe form of injuries even death by road traffic accidents, this unfortunately also becomes a socio economic problem. Non helmet wearing is the major risk factor in fatality for motor bike accidents. By putting into effect laws that enforce road safety measures and helmet usage can prevent these injuries.
Key Words: Motor bike , Helmet and Karachi.

Introduction

The Global status report on road safety 2013 presents information Worldwide, the number of people killed in road traffic crashes each year is estimated at almost 1.24 million, while the number injured could be as high as 50 million – the combined population of five of the world’s large cities. It was the 2nd leading cause of deaths among 15 – 44 years of age and 80%
of these deaths occurred in developing countries[1]. By 2020 road traffic accidents are expected to be the 3rd leading cause of death and disability worldwide[2]. According to the World Health Organization (WHO) 2011 fact sheet, “over 90% of the world’s fatalities on the roads occur in low-income and middle-income countries, even though these countries have less than half of the world’s vehicles.”1 In a 2009 report, WHO estimated that in Pakistan road traffic injuries result in 25.3 deaths per 100,000,2 which is high by the international organization’s standards. Currently it is the 9th leading cause of disability and adjusted life year lost globally, moreover 90% of the disability and adjusted life year lost occurs in developing countries worldwide due to road traffic accidents[3]. Being economical and convenient city traffic the use of motorbikes has increased tremendously during the last few years.
Almost percentage of the inhabitants of Karachi belongs to lower middle class and relies on motor bikes as the main mode of transportation in Karachi. In 2010 the number is estimated to climb to 3.6 million by According to an article published in Dawn, there were about 1 million motorbikes the year 2030. Unfortunately motorcyclists also contribute to a significant number in the mortality and morbidity in road traffic accidents. Even in developed countries, the accident risk of motorcycles is 20 times more per kilometer than drivers of other vehicles[4-6] .non helmet wearing is one of the most important factor in fatality in bike riders.

Methods:
It is cross sectional study conducted by ROAD TRAFFIC INJURY RESEARCH AND PREVENTION CENTRE “RTIR&PC” in emergency department of all five major hospitals in Karachi including Jinnah Postgraduate Medical Center, Civil hospital, Abbasi Shaheed Hospital, Aga Khan Hospital and Liaqat Hospital Karachi. . All male motorbike accident victims presented to the emergency department of the selected hospital, were included in the study. Inclusion criteria were injured patients of any age or sex presenting to the Accident, Emergency . A pretested trauma registry form was completed for all patients. If the patient was brought unconscious, an attempt was made to collect the information from the patient’s attendant. Basic demographic characteristics, time and date, nature and cause of injury, vital signs and outcome data were recorded. Type of vehicle and mode of collision was recorded in cases of road traffic accident.

Chart 1: Distribution of total injuries and sub classifications

Chart 1: Distribution of total injuries and sub classifications

 

Chart 2: Distribution of fatalities and anatomical injuries

Chart 2: Distribution of fatalities and anatomical injuries

 

Results:
Total numbers of accidents were 24360 and total number of injured were 30274. Minor injury 23825 (approximately 78.6%, around 65 per day), serious were 5382 (approximately 17%, around 15 per day) and fatal were 1067 (approximately 3.5%, around 3 per day). Bike rider injuries were most common around 25855 (approximately 85% of all injuries) and fatal bike rider accident were 506 (approximately 47% of all fatalities) (Chart 1). Helmet wearing bike riders were only 1123 (approximately 4.3%) and non helmet wearing were 16681 (approximately 64.5%). Injuries related to body part were , head and neck- 23%, fatal were 53%; face -17% ,fatal were 16%; chest -1% fatal 1%; abdomen, pelvic contents -1% fatal 1%; extremity & pelvic girdle- 29% fatal 17%; external injuries -28% fatal 12%. The most common mortality is due head and neck injuries which are due to not helmet wearing among bike riders (Chart 2).

Discussion:
Trauma is increasingly recognized as a global public health epidemic. WHO has predicted that trauma will rise from 9th leading burden of disease in 1990 to third leading cause in 2020 worldwide 8. In present study we found that annual incidence of trauma in road traffic accidents are commonly affecting bike rider which also have the highest fatality percentage among all road traffic accidents. We also found out that head and neck injuries are the commonest cause of fatality in these incidences and non helmet wearing is the commonest cause.
A study on An autopsy-based study of death due to road traffic accidents in metropolis of Karachi found out that Death were due to injury to the head (66.4%) victims, to the chest (14.5%) cases, multiple traumatic injuries in (8.6%) and pelvis (2.9%) cases.9
It is estimated that 45% of road traffic fatalities in low income countries are among pedestrians, whereas an estimated 29% in middle-income and 18% in high income countries are among pedestrians[24]. In Hong Kong, pedestrians accounted for 70% of RTA fatalities. On the other hand, in China, Malaysia and Thailand, pedestrian deaths are between 10-15% but over 50% of deaths due to RTA involved motorcyclists[10].
Unsurprisingly, the non-compliance of motorcyclists to wear helmets and the vulnerability of pedestrians accounts for head injuries proving fatal in 47% of the cases.: In a study in Nigeria, the most common cause of death was head injury 48.3%11 while in Singapore the second most common cause of death was head injuries 30.9%[12].

Conclusion:
Injuries in city of Karachi are an important public health problem and contribute to major bulk of Emergency facilities. Motorbike riders are known to be more vulnerable to road accidents and became victims of severe form of injuries even death by road traffic accidents, this unfortunately also becomes a socio economic problem. Non helmet wearing is the major risk factor in fatality for motor bike accidents. By putting into effect laws that enforce road safety measures and helmet usage can prevent these injuries.

References

1. World Health Organization. WHO: Road traffic injuries. Fact sheet N°358. (Online). September 2011 (Cited 2012 Feb 28). Available from URL: http://www.who.int/mediacentre/factsheets/ fs358/en/index.html.
2. World Health Organization. Global status report on road safety: Time for action. (Online). 2010 (Cited 2012 Feb 28). Available from URL: http://whqlibdoc.who.int/publications/2009/9789241563840_eng. pdf
3. Nantulya VM, Reich MR. The neglected epidemic: road traffic injuries in developing countries. British Med J 2002;324:1139-41.
4. Dischinger PC, Ryb GE, Ho SM, Braver RE. Injury patterns and severity among hospitalized motorcyclists: a comparison of younger and older riders. Annu Proc Assoc Adv Automot Med 2006;50: 237-49.
5. Solagberu BA, Ofoegbu CK, Nasir AA, Ogundipe O, Adekanye A, Abdur-Rahman A. Motorcycle injuries in a developing country and the vulnerability of riders, passengers, and pedestrians. Inj Prev 2006;12:226-8.
6. Peden MM, Scurfield R, Sleet D ,Mohan D,Hyder AA.World report on road traffic injury prevention. Geneva:
World Health Organization; 2004.11p.
7. Ilyas , F. (2014, July 2). Loose dresses and dupattas major cause of road traffic injuries: study. Daily Dawn. Retrieved from http://www.dawn.com/news/1116432
8 Murray, C.J. and A.D. Lopez, Alternative projections of mortality and disability by cause 1990-2020: Global Burden of Disease Study.Lancet,1997. 349(9064): p.1498-504.
9 An autopsy-based study of death due to road traffic accidents in metropolis of Karachi Farhat Hussain Mirza, Qudsia Hassan, Nadia Jajja
Vol. 63, No.2, February 2013 JPMA page 156-160
10 Jacobs GD, Thomas AA. A review of global road accident fatalities. (Online) 2000 (Cited 2012 March 2). Available from URL: http://www.transport-links.org/transport_links/filearea/ publications/1_771_Pa3568.pdf
11 Osime OC, Elusoji SO, Eboreime O. Pattern and outcome of road traffic accidents in a suburban community in Nigeria. Annals of Biomedical Sci 2009; 8(1)
12. Wong ZH, Chong CK, Tai BC, Lau G. A review of fatal road traffic accidents in Singapore from 2000 to 2004. Ann Acad Med Singapore 2009; 38: 594-9.

How to Cite this article: Kumar R , Muzzamml M, Minhas MS. Frequency of motor bike injuries, helmet vs non helmet wearing in Karachi Pakistan. Trauma International. Jan-Apr 2016;2(1):34-36.

Dr. Ranjeet Kumar

Dr. Ranjeet Kumar

Dr. Muhamad Muzamil

Dr. Muhamad Muzamil

Dr. Kashif Mahmood

Dr. Kashif Mahmood

Prof Anisuddin Bhatti

Prof Anisuddin Bhatti

Prof Saeedi Minhas

Prof Saeedi Minhas

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