Fractured Femoral Stems in Primary and Revision Hip Arthroplasties Revisited: Wrightington Experience.

BACKGROUND

The aim of this study is to present our experience in managing fractured femoral stems over the last 10 years for both primary and revision stems at our tertiary unit focusing on modes of failure and operative techniques.

METHODS

This is a retrospective consecutive study of all patients with fractured femoral stems that were operatively managed in our unit between 2008 and 2018. Detailed radiographic evaluation (Paprosky classification) was undertaken and data collected on operative techniques used to extract distal fractured stem fragments.

RESULTS

Thirty-five patients (35 hips) were included (25 men/10 women) with average age at time of presentation of 68 years (range, 29-93). Average body mass index was 30 (standard deviation, 3.8; range, 22.5-39). There were variety of stems both contemporary and historical, primary and revision cases (15 hips polished tapered cemented stems, 10 hips composite beam and miscellaneous stems, and 10 revision hip stems). The predominant mechanism of failure was fatigue due to cantilever bending in distally fixed stems. Surgical techniques used to extract distal fragment were drilling technique in 2 hips, cortical window in 13 hips, extended trochanteric osteotomy (ETO) in 5 hips, and proximal extraction in 15 hips.

CONCLUSION

When faced with a contemporary fractured stem, drilling techniques into the distal fragment are unlikely to succeed. If a trochanteric osteotomy had been used at time of index surgery, this could be used again to aid proximal extraction with conventional revision instrumentations. The cortical window technique is useful but surgically demanding technique that is most successful in extracting polished tapered fractured stems particularly when an ETO is not planned for femoral reconstruction. Use of trephines can be useful for removal of longer, uncemented stems. Finally, an ETO might be necessary when other techniques have failed.