Long-term Outcome of Total Femur Replacement.

Introduction: Total femur replacement is an option instead of amputation for extensive bone tumour or after revision surgery with a massive bone loss. Over a long period of time the patients may need revision surgery, and this might affect the functional outcome. We reviewed all consecutive total femur replacements done for primary and revision surgery of primary bone tumours in our centre to evaluate the long-term functional outcome and survival.

Materials and methods: All patients who had total femur resection and reconstruction with modular endoprosthesis replacement in our centre from June 1997 to May 2022 were reviewed. The respondents were surveyed through WhatsApp using google form which was translated into Bahasa Malaysia based on the Musculoskeletal Tumour Society Scoring System (MSTS). The data were presented as descriptive data on the final survival of the limb and prosthesis.

Results: Ten patients underwent total femur replacement. There were eight osteosarcoma, one giant cell tumour and one chondromyxoid fibroma. Three patients with osteosarcoma succumbed to pulmonary metastases; all had good early post-operative functional outcomes without local recurrence. Seven patients were available for long term evaluation of function with a mean follow-up of 17.6 years (ranged 10-25 years). Four patients with total femur replacement had good functional outcomes (60-80%) without revision with 10-25 years follow-up. Three patients experienced acetabulum erosion and chronic pain that required early hip replacements. Two of them were complicated with superior erosions and bone loss and subsequently were managed with massive reconstruction using cemented acetabulum cage reconstruction. The other has diabetes mellitus with chronic infection following revision of distal femur endoprosthesis to total femur replacement and subsequently underwent limited hemipelvectomy after 14 years.

Conclusion: Total femur replacement offers a good long term functional outcome and prosthesis survival and is a favourable option for limb salvage surgery.