Distal femur resection with endoprosthetic reconstruction: a long-term followup study.

The distal femur is a common site for primary and metastatic bone tumors and therefore, it is a frequent site in which limb-sparing surgery is done. Between 1980 and 1998, the authors treated 110 consecutive patients who had distal femur resection and endoprosthetic reconstruction. There were 61 males and 49 females who ranged in age from 10 to 80 years. Diagnoses included 99 malignant tumors of bone, nine benign-aggressive lesions, and two nonneoplastic conditions that had caused massive bone loss and articular surface destruction. Reconstruction was done with 73 modular prostheses, 27 custom-made prostheses, and 10 expandable prostheses. Twenty-six gastrocnemius flaps were used for soft tissue reconstruction. All patients were followed up for a minimum of 2 years. Function was estimated to be good or excellent in 94 patients (85.4%), moderate in nine patients (8.2%), and poor in seven patients (6.4%). Complications included six deep wound infections (5.4%), six aseptic loosenings (5.4%), six prosthetic polyethylene component failures (5.4%), and local recurrence in five of 93 patients (5.4%) who had a primary bone sarcoma. The limb salvage rate was 96%. Distal femur endoprosthetic reconstruction is a safe and reliable technique of functional limb sparing that provides good function and local tumor control in most patients.