Rotationplasty performed in adults versus minors: a comparative study of long-term quality of life, functional and biomechanical outcomes.

Background: Rotationplasty is a surgical technique primarily used in pediatric patients with malignant bone tumors around the knee. Its application in adults is rare, and outcomes are poorly defined. This study aimed to compare long-term QoL, function, and gait between patients treated with rotationplasty in childhood versus adulthood. Methods: This cross-sectional post-hoc predefined secondary analysis included 33 patients treated between 1980-2002 (9 adults, 24 minors). Assessments included the mental and physical component score of the Short Form-36 (SF-36, MCS/ PCS), overall satisfaction, radiographs (Kellgren-Lawrence) of the pseudo-knee, contralateral ankle, and hips, Toronto Extremity Salvage Score (TESS), Musculoskeletal Tumor Society Score (MSTS), energy cost of comfortable walking during a 6-minute walk test, and 3-Dimenional gait analysis. Group comparisons were performed across all outcomes. Additionally, a systematic literature search identified published adult cases. Results: People who underwent surgery during adulthood reported significantly higher physical QoL compared to those operated in childhood (MD 6.1, 95 % CI 0.0-12.3; p = 0.05). No significant differences were observed for the SF-36 MCS, TESS, MSTS, energy cost, sagittal-plane biomechanics, and radiographic OA prevalence. Adults exhibited a significantly shorter stride length (p < 0.01) and a longer double support phase (p = 0.01) compared to those treated in childhood. The literature review (22 studies, 51 patients) demonstrated overall favorable outcomes, though no objective gait data were reported. Conclusion: Adults who undergo rotationplasty can achieve long-term quality of life, functional, and gait outcomes at least comparable to those operated on in childhood. These findings suggest that rotationplasty may be a viable reconstructive option in adults.