Implant survival and risk factors for failure after proximal femoral megaprosthetic reconstruction.

BACKGROUND

Proximal femoral megaprosthetic reconstruction is a well-established solution for extensive bone loss in the hip region. Despite its utility in limb salvage, it carries notable complication rates, reported between 30% and 40%, along with increased morbidity and mortality. This study evaluated implant and patient survival, failure modes, and associated risk factors.

METHODS

We retrospectively reviewed 165 patients who underwent proximal femoral megaprosthetic reconstruction between 2003 and 2023. Indications included primary bone tumors (n = 67), metastatic bone disease (n = 60), and non-oncologic conditions (n = 38). A total of 57 METS (Stanmore) and 108 MUTARS (Implantcast) implants were used. Median follow-up was 5 years (range: 0.25-17 years).

RESULTS

Mean implant survival was 5.13 years (range: 0.2-17 years), with an overall complication rate of 30.9%. The most common failure modes were type 1 (11.5%) and type 4 (13.3%) per Henderson classification. Five-year implant survival ranged from 60% to 70% across indications. Independent risk factors for type 4 failure included prolonged hospitalization (OR = 1.07, p = 0.020) and longer operative time (OR = 1.01, p = 0.023). Silver-coated implants showed a trend toward reduced infection (OR = 0.18, p = 0.29), though not statistically significant. METS implants were associated with lower type 1 failure risk (OR = 0.09, p = 0.020), with a soft-tissue failure rate of 3.5% versus 15.7% for MUTARS.

CONCLUSION

Proximal femoral megaprostheses remain effective for limb salvage but are linked to a substantial complication burden. Recognition of modifiable and patient-specific risk factors may improve surgical outcomes and reduce failure rates.