Functional results after through-knee and above-knee amputations: does more length mean better outcome?

The objective was to evaluate our results on functional outcome for both through-knee amputations and above-knee amputations. Functional outcome was measured using the Special Interest Group in Amputee Medicine score, which focuses on walking distance and use of prosthesis. From 1997 to 2006, 39 through-knee amputations (53%) and 34 above-knee amputations (47%) were performed. Eight (21%) of 39 through-knee amputations needed to be converted to above-knee amputations. Fifty patients (24 above-knee amputations, 26 through-knee amputations) were eligible for follow-up. During follow-up, 71% (of above-knee amputations) and 69% (of through-knee amputations) did not walk with a prosthesis, and 29% of above-knee amputations and 27% of through-knee amputations walked more or less than 50 m. In conclusion, only a minority of patients is able to walk with a prosthesis, and a lot of the through-knee amputations need conversion to a higher level. On the basis of this results, it would be preferable to perform a straight above-knee amputation instead of a through-knee amputation if the correct amputation level is in doubt in high-risk patients.