Improved Gait and Patient-Reported Outcomes Following Hip Preservation Procedures Via Surgical Hip Dislocation Approach in Adolescents With Residual Legg-Calvé-Perthes Disease

BACKGROUND: Adolescent patients with hip dysfunction due to residual deformity in the healed stage of Legg-Calvé-Perthes disease (LCPD) remain a treatment decision-making challenge. Some advocate hip preservation via the surgical hip dislocation (SHD) approach, with concomitant procedures to address various hip pathologies. Currently, hip movement and gait analysis data before and after the SHD approach are lacking. This study aimed to determine the gait parameters, patient-reported outcomes, and radiographic outcomes of adolescent patients with LCPD who had hip preservation procedures via SHD. METHODS: A retrospective review of a prospectively collected database at a single tertiary referral center was conducted for patients in the healed stage who had hip preservation procedures via SHD. We included patients who had preoperative and a minimum of 1-year postoperative gait analysis. Patient-reported outcomes included the UCLA Activity Score and modified Harris Hip Score (mHHS). Radiographic assessment included Stulberg classification and Sphericity Deviation Score (SDS). Similarly aged healthy controls were used for comparison of gait parameters. RESULTS: Thirty-nine patients met the inclusion criteria, with a mean age at surgery of 16.55±2.56 years and a mean time point for post-SHD gait analysis of 2.02±0.64 years. There was improvement in the mHHS (preop: 58.59±12.98, postop: 72.12±11.36, P=0.0001) and UCLA Activity Score (preop: 6.41±2.55, postop: 8.28±2.11, P<0.001). Gait analysis revealed improved walking speed (P=0.02), stride length (P<0.001), Gait Deviation Index (P=0.03), maximum degree of hip extension (P<0.01), and power generated during hip flexion (P=0.01). Hip abduction function showed no change (P=0.15). Five hips improved from Stulberg IV to III (P=0.10). There was no difference in SDS (P=0.95). CONCLUSION: Hip-preservation procedures via SHD produced significant improvements in gait parameters and patient-reported outcomes without loss of hip abduction function, but no improvement in SDS. This study provides new insights into how hip-preservation procedures via SHD improve gait and function in adolescent patients with LCPD and residual hip deformity. LEVEL OF EVIDENCE: Level III retrospective cohort study.