Abstract
BACKGROUND: Knee osteoarthritis (OA), a common degenerative joint disease. Anteromedial osteoarthritis (AMOA) specifically targets the knee's medial compartment. We compared total knee arthroplasty (TKA) and mobile-bearing unicompartmental knee arthroplasty (MB-UKA) regarding postoperative functional mobility and quality of life in patients with AMOA. METHODS: A retrospective comparative analysis was conducted on 193 AMOA patients who received TKA (n=101) or MB-UKA (n=92) treatment between January 2020 and December 2024. Patient outcomes were evaluated two years postoperatively using range of motion (ROM), visual analog scale (VAS) for pain, the simplified Chinese version of the Forgotten Joint Score (SC-FJS), Hospital for Special Surgery (HSS) Knee Score, Oxford Knee Score (OKS), Knee Injury and Osteoarthritis Outcome Score (KOOS), and SF-36 quality of life questionnaire. RESULTS: MB-UKA demonstrated superior functional outcomes. MB-UKA showed significantly greater improvement in ROM (124.44° vs 121.94°, P<0.001) and SC-FJS scores (90.52 vs 89.25, P=0.002) at two years. Mechanical axis alignment was also significantly better in the MB-UKA group (178.65° ± 0.35° vs 178.53° ± 0.41°, P=0.025). Functional mobility was enhanced with MB-UKA, as indicated by higher HSS (P=0.003), OKS (P=0.002), and KOOS (P=0.002) scores. MB-UKA patients reported better physical functioning (PF score: 68.98 vs 66.52, P=0.008) and vitality (VT score: 81.14 vs 78.96, P=0.009) on the SF-36. CONCLUSION: MB-UKA offers enhanced functional mobility and quality of life compared to TKA for patients with AMOA, while maintaining a comparable safety profile. MB-UKA should be considered a favorable surgical option for appropriately selected patients seeking optimized functional recovery.