Short- and Long-Term Outcomes in Patients With Lower Extremity Amputations Undergoing Total Hip and Knee Arthroplasty.

Background: Joint replacement following amputation is scarcely reported. The primary aim of this study was to evaluate patient-reported outcomes (PROMS) and revision rates among lower extremity amputees undergoing total hip (THA) or knee arthroplasty (TKA).

Methods: This was a retrospective cohort analysis of lower extremity amputees undergoing THA/TKA between August 2002 and August 2022 in a single tertiary center. Demographic and clinical data were collected from prospectively populated surgical databases and patient electronic records. PROMS included Oxford Knee Score, Oxford Hip Score, and 5-level EuroQol 5-dimension questionnaires. Twenty-three TKAs and 21 THAs were performed in 38 patients. The mean age at arthroplasty procedures was 59.8 (24-87) years. The mean clinical follow-up duration for THA and TKA was 9.1 and 4.5 years, respectively. Seven TKAs and 6 THAs were ipsilateral to the amputated side.

Results: The 10-year revision rates were 9.5% (2/21) and 5.9% (1/17) in the TKA and THA cohorts, respectively. TKA revisions occurred due to aseptic loosening. Six (26%) TKA cases experienced stump complications. Overall PROMS completion was 61.9% (13/21) and 64.7% (11/17) in TKA and THA patients, respectively. The average Oxford Hip Score/Oxford Knee Score of THA and TKA cohorts were 40.8 and 34.2, respectively. EuroQol 5-dimension questionnaire visual analog scores were higher in the THA cohort than those in the TKA cohort without statistical significance (59.1 vs 50.5,  = .214). The overall survival rate for the study was 94.7% at 5 years (36/38).

Conclusions: TKA/THA in lower extremity amputees can be successful, with low revision rates and good prosthesis function. Potential pitfalls highlighted include prosthesis malalignment, postprocedural rehabilitation, and stump complications.