Fixation of Vancouver B fractures around Taper slip femoral stems: Picking winners

Authors:
Ali Assaf, Khaled Al-Kharouf, Mohammed Amer, Douglas Dunlop

Hospital:
University Hospital Southampton

Introduction:
Fixation of Vancouver B Proximal Femoral Fractures (VBPFFs) around Cemented Taper Slip stems (CTSS) where the bone cement interface is intact, has shown reduced blood transfusions and reoperations, compared to revision arthroplasty. Whether fixation is appropriate for all VBPFFs or a more selective approach would help reduce risks of subsidence and loosening is still unknown.

Methods:
All VBPFFs in primary THR around CTSS at SGH were reviewed. Primary outcome was revision rate. There was a variety of secondary outcomes.

Results:
50 VBPFFs were included. Average follow-up time was 13months. Mean age at fracture was 79years, mean ASA 2.8, average LOS 24days, with 33% mortality at 5years.
Revision rate was 10%(5/50). Two revised for loosening and 3 for non-union and failure of metalwork. Subsidence rate was 48%. Subsidence was associated with negative symptoms (P<0.0001). Major subsidence, observed in 8 patients, equated to significant mobility reduction. No dislocations were observed. There was 1 chronic infection treated with suppressive antibiotics.
High spiral and metaphyseal split fractures had higher subsidence rate (100% and 68%respectively) compared to low spirals and short oblique (11% and 0%respectively). The average EBL was 414ml, with 5 patients requiring transfusions.

Conclusions:
Our revision rate and EBL Results are consistent with the available literature. The high rate of subsidence is alarming and might be more reflective of functional outcomes than revision rates. A more selective approach utilizing a morphology based classification can help reduce the incidence of subsidence and maintain the benefits of osteosynthesis only.