Provision of Rotational Stability: Prevention of Collapse: Closed Fracture Reduction: Minimally Invasive Surgery with no Exposure of the Fracture:

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3 INTRODUCTION Percutaneous Compression Plating was developed by considering each of the stages in the surgical procedure for pertrochanteric fractures and the ways in which these might be improved. Primary objectives were that there should be minimal operative trauma and blood loss in patients whose general condition is frequently compromised by severe concomitant medical or surgical conditions, and that walking ability should be maintained. Its use in both stable and unstable pertrochanteric hip fractures has resulted in improved outcomes 1,2,3. This new system represents a minimally invasive method of fracture stabilization and fixation, providing enhanced rotational stability 4 and bone sparing 6. The technique reduces both operative and post-operative complications including cut outs and fracture collapse 1,2. A statistically significant reduction in post-operative pain has been recorded 3. Weightbearing may be permitted immediately post-operatively. The PC.C.P technique is designed around four fundamental principles: 1. Closed Fracture Reduction to a 135 shaft/neck angle 2. Minimally Invasive Surgery with no Exposure of the Fracture 3. The Provision of Rotational Stability 4. Prevention of lateral wall fracture and hence of fracture Collapse Closed Fracture Reduction: Posterior fracture sagging must be reduced and reduction maintained until fixation is complete. Use of the posterior reduction device (PORD device) facilitates this procedure and is therefore an integral feature of the Percutaneous Compression Plating technique1. In the past, the plate-screw or nail-screw angle of a fixation device has been chosen according to the shaft / neck angle achieved during fracture reduction. Plates have classically been produced with a range of different angles. Since, however, a shaft / neck angle of 135 has been shown to be superior, biomechanically, for both fracture impaction and fixation device sliding 7,8, it follows that this is the angle to which the fracture should be reduced, thereby optimizing impaction, and hence, fracture healing. The PC.C.P technique ensures that this angle is achieved. Minimally Invasive Surgery with no Exposure of the Fracture: Minimally invasive surgical techniques have proven successful in reducing operative complications and post-operative morbidity 9. This is particularly relevant in relation to pertrochanteric hip fractures. The present technique was specifically designed with this requirement in mind. Provision of Rotational Stability: Single-axis fixation provides poor control of rotational stability 10. The PC.C.P provides double-axis telescoping fixation, which also increases the projection area within the femoral head. Biomechanical studies with the PC.C.P have revealed a significant increase in rotational stability which is critical for providing controlled fracture impaction 4. This is the post-surgical compression, passively exerted by the patient, and is provided by a fixation device which has a sliding capability, as well as rotational stability. Rotational instability has been reported to cause irreversible caudal shift and varus tilt of the femoral head 11, which may result in femoral head cut out, a frequently reported complication of intertrochanteric fracture fixation 12,13,14. That this complication is not associated with PC.C.P fixation has been attributed to the improved rotational stability provided by the double axis telescoping mechanism. Prevention of Collapse: Traditionally, the medial and postero-medial fracture fragments have been considered to be the most important elements in determining the severity of the pertrochanteric hip fracture. This is certainly true, but only in assessing the extent of the bony damage. The trochanteric portion which is not broken, and which remains for fracture reconstruction, namely the lateral wall is, however, no less important. This portion provides the best opportunity for osteosynthesis with the proximal part of the fracture complex, since it is the proximal extension of the femoral shaft. In an unstable three or four part pertrochanteric fracture, the lateral wall is very fragile and fracture of this delicate structure will convert an pertrochanteric fracture into what is effectively a subtrochanteric fracture, which is a more severe problem and should be avoided at all costs 5. An intact lateral wall, therefore, plays a key role in the stabilization and fixation of unstable pertrochanteric fractures. By providing a lateral buttress for the proximal fragment, fracture impaction is facilitated, and followed by rotational and varus stability once fracture spike impaction occurs. If the lateral wall is broken, there is no lateral buttress for the proximal neck fragment and collapse will follow 5,6. This has been reported to be a major contributor to post-operative morbidity 15,16 as it is followed by a long period of disability. No lateral wall damage and no fracture collapse have been reported with use of the PC.C.P 1,2. This is attributed to the small diameter of the holes at the drilling site with PC.C.P following incremental drilling from 7 to 9.3 mm, compared with the mm drilling required for the screw barrel of the dynamic/compression hip screw. 1

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7 EQUIPMENT REQUIRED Gotfried PC.C.P Instrument Case Upper Tray Q Q Lower Tray Q Q Q Q Q Q

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23 OPERATIVE TECHNIQUE The shaft sleeve (203000) and shaft trocar (204000Q) are now inserted through either the proximal or distal vertical hole of the introducer using the small skin retractor to assist entry into the incision. The shaft sleeve is locked into position with a bolt (194000) inserted through the introducer, and the shaft trocar withdrawn. 3 Note that the shaft trocar has three additional functions: 1. A triangular hole for attachment to the shaft Screwdriver if manual application of the shaft screws is desired. 2. A cylindrical protrusion to assist in turning the grips of the neck Screwdriver. 3. A short Screwdriver for the neck screw barrel. 1 2 The 3.2 mm step drill bit is now used to predrill the bone. 21

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25 OPERATIVE TECHNIQUE The bone hook is now removed by simply reversing the steps used for its insertion. The butterfly pin must now be removed. The remaining two shaft screws are now inserted as described above, followed by the second (proximal) neck screw. This neck screw is also inserted using the main guide in order to measure the length of screw required. Following screw introduction, the barrel is impacted to minimally deform the thread in the plate as before. The introducer is now unlocked (butterfly screw) and removed. The wound is now irrigated, and a suction drain left in situ for twenty four hours. The subcutaneous tissues and skin are closed in the normal manner and a full length elastic bandage or stocking applied to the lower extremity. 23

26 POST-OPERATIVE MANAGEMENT Post-operatively, full weightbearing may be allowed immediately, initially with a walking frame and subsequently with crutches. 24

27 Orthofix wishes to thank Dr. Y. Gotfried, MD, MS for his invaluable help in the preparation of this manual

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