Open reduction, internal fixation of Vancouver B1, C & D type periprosthetic femoral fractures with use of an antiglide plate at fracture apex - The “Apex Plate”

Abstract

Background

Periprosthetic femoral fractures are associated with significant morbidity, mortality, social and economic cost. The incidence of these fractures is expected to increase with an ever-growing elderly world-population. The complex nature and varied pattern of these injuries requires a range of specialized surgical techniques and tools. Fixation alone is being increasingly regarded as the preferred method of addressing these fractures, even in cases where the femoral stem is unstable, showing favourable outcomes overall when compared to a fix-and-replace approach. Lateral plate fixation is the primary surgical method for either case, and while there is a growing offer of implants specifically for this subset of orthopaedic injuries, the problem of non-union appears to be the most common of complications encountered postoperatively. We prefer fixation alone, including for Unified Classification System (UCS) B2 and B3 type fractures. A small-fragment plate fixed at the fracture apex acts as both a reduction device, thereby simplifying the operation itself, and as a buttressing device. The lateral tension-banding plate method can exploit the latter function of this smaller plate to improve the stability of the fixed construct, and thereby encourage more reliable bone healing.

Cases

We have treated 6 patients between the ages of 59 and 93 with UCS B1, B2, C and D fractures in this fashion. Fragments around an unstable stem (as with a UCS B2 or B3 fracture) were first reduced anatomically and fixed using cerclages, effectively creating a UCS B1, C or D type fracture, which can then be addressed using this two-plating system. All patients were discharged from hospital, returning home to activities of daily living. All radiographic follow-up demonstrated maintenance of reduction and implant position. For patients with radiographic follow-up beyond two months, fracture consolidation or partial consolidation was noted. No surgical infections were recorded.

Conclusions

We present this method of fixation for these types of fractures as a “mixed principles” approach to osteosynthesis. Here, the buttressing nature of the medial femoral cortex is at least in part reconstituted so that compressive forces are generated across cortices where an oblique or spiral fracture pattern would otherwise generate shear forces. Re-establishing these biomechanics with a lateral tension band plate, we assume, generates a more stable construct that favours bone healing and reduces the chances of non- or mal- union.