Context: Some patients seeking transcutaneous osseointegration for amputees (TOFA) have residual bones so short there is concern whether they provide sufficient surface to support full weight. Our strategy was to lengthen these patients' femurs with a motorized intramedullary lengthening nail (MILN) before TOFA. Aims: The aim of this study is to describe 10 transfemoral amputees' experience with MILN before TOFA, focusing on the complications of MILN and TOFA, and also the patients' preoperative and postoperative quality of life (QOL). Settings and Design: A retrospective registry review of all MILN before TOFA surgeries was performed. Subjects and Methods: The patients' operative complications during/following MILN and TOFA were investigated. Furthermore, the patients' mobility (daily prosthesis wear hours, K-level, Timed Up and Go (TUG), and 6 min Walk Test [6MWT]) and QOL survey data (Questionnaire for Persons with a Transfemoral Amputation [QTFA]) were compared at the initial consultation and at the latest follow-up using Fisher's exact test for frequencies, and Student's t-test for means (significance, P < 0.05). Statistical Analysis Used: Fisher's exact test for frequencies, and Student's t-test for means (significance, P < 0.05). Results: Seven patients had one operative complication each: Three regenerate (autograft and plating), two nail malfunctions (nail replacement), one broken linkage cable (acute length correction with autografting and fixation), and one early consolidation (re-osteotomy). All ten patients had TOFA, an average of 12.0 ± 3.9 months after MILN surgery. One patient had debridement for infection (implant retained) and one patient had the implant removed due to infection. Significant mobility improvements were K-level >2 (2/9 = 22% vs. 9/10 = 90%, P =0.006) and TUG <15 s (1/8 = 13% vs. 6/8 = 75% P = 0.041). Wear hours and 6MWT improved but not significantly. All three aspects of QTFA significantly improved: Global (44.8 ± 29.9 vs. 75.9 ± 26.8, P =0.050), mobility (50.3 ± 30.8 vs. 74.8 ± 18.2, P =.033), and problem (38.8 ± 18.6 vs. 15.6 ± 18.3, P = 0.017). Conclusions: MILN before TOFA reliably achieves stable osseointegration for amputees with short residual femurs. Amputee lengthening remains demanding, but patients report significantly improved QOL and demonstrate improved mobility following TOFA. The minimum length of bone necessary to support a full weight-bearing osseointegrated prosthesis remains unknown.
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