Evaluation of a Noninvasive Expandable Prosthesis in Musculoskeletal Oncology Patients for the Upper and Lower Limb

Abstract

The noninvasive expandable prosthesis is used for limb-salvage surgery following tumor resection in skeletally immature patients. The purpose of this retrospective study is to report our experience with the Repiphysis (Wright Medical Technology, Inc; Arlington, Tennessee) noninvasive expandable prosthesis for both the lower extremity and compassionate use in the upper extremity in 12 patients between 2003 and 2008. Twelve prostheses were implanted in 12 patients with an average follow-up of 38 months (range, 12-78 months). Nine patients underwent a total of 38 expansion procedures. Mean total expansion was 4.5 cm (range, 0.8-9.9 cm). No complications of lengthening occurred. Seven nononcologic complications were noted. One infection was reported in 12 patients. The mean MSTS score after rehabilitation was 24.5 (range, 13-30). The Repiphysis noninvasive prosthesis provides acceptable functional outcomes for both upper and lower extremity implantation and appears to have an advantage as compared to conventional expandable prosthetics, which require open procedures that can potentially increase the risk of infection from repeated hardware exposure.

Are Complications Associated With the Repiphysis® Expandable Distal Femoral Prosthesis Acceptable for Its Continued Use?

“…However, the most frequent reason for revision was prosthetic failure attributable to spring breakage (eight cases). Younger patient age and longer followup in our current series compared with previous studies [2,11,17,22] might have influenced the results. Longer followup obviously exposes the implant to more risks of failure.…”

“…Patient age could partially explain the difficulties in pain management with our patients. Our patients were younger, with a mean age of 8 years at index surgery, whereas in other series the patients were older than 10 years [2,4,11,18,22]. Furthermore, the amount of lengthening was unpredictable and difficult to control.…”

“…Early reports showed promising preliminary results [11,17,26], with good-to-excellent function and a relatively low complication rate. MSTS scores in the early series with relatively short followup varied from 81.7% to 90% [2,11,17,18,22], but in the only previous series with an average followup of more than 6 years, the final MSTS score was on average 67% [4] ( Table 3).…”

“…We asked (1) what are the clinical outcomes using the Musculoskeletal Tumor Society (MSTS) scoring system after 5-year minimum followup in patients treated with this expandable prosthesis; (2) what are the problems and complications associated with the lengthening procedures of the implant; and (3) what are the specific concerns associated with revision of the implant?…”

“…Early reports on the device were positive but more recently, a high complication rate and associated bone loss have been reported. Questions/purposes We asked: (1) what are the clinical outcomes using the Musculoskeletal Tumor Society (MSTS) scoring system after 5-year minimum followup in patients treated with this prosthesis at one center; (2) what are the problems and complications associated with the lengthening procedures of this implant; and (3) what are the specific concerns associated with revision of this implant? Methods At our institute, between 2002 and 2007, the Repiphysis 1 expandable prosthesis was implanted in 15 children (mean age, 8 years; range, 6-11 years) after distal femoral resection for malignant bone tumors.…”