Characterizing The Gait Profiles Of Sexually-Immature Pediatric Patients Following Anterior Cruciate Ligament Reconstruction

Rates of pediatric anterior cruciate ligament (ACL) injuries are increasing faster than in adults. Despite the known link between aberrant walking biomechanics and knee osteoarthritis development in adult patients post-ACL reconstruction (ACLR), limited research has characterized the walking biomechanical profiles of pediatric patients post-ACLR. PURPOSE: To compare the biomechanical profiles of pediatric ACLR patients (Tanner Stage I-IV) to uninjured, matched pediatrics (Tanner Stage category; sex) and adult-matched ACLR patients (months post-ACLR ±2; sex). METHODS: Gait biomechanics were measured overground in pediatric ACLR participants (n=15, 15±1 yrs.; 10±5 months), pediatric controls (n=15; 15± 1 yrs.), and adult ACLR patients (n=15; 23±3 yrs; 10±5 months). Tanner stage category was defined as early (I-II) and mid/late puberty (III-IV). A functional mixed-effects model compared biomechanical variables between groups. RESULTS: The pediatric ACLR group demonstrated lesser vertical ground reaction force (vGRF) (significant stance phase region: 7-14;16-26%) and knee flexion angle (KFA) in early stance (12-31%), and lesser KFA in mid to late stance (50-87; 97-101%) compared to uninjured pediatrics. Pediatric ACLR patients walked with lesser vGRF in midstance (54-62%) but greater vGRF in late stance (90-93%) compared to the adult ACLR group. Pediatric ACLR patients demonstrated lesser KEM in early and late stance (13-33; 67-84%) compared to the uninjured pediatrics. No differences in knee extension moment (KEM) were observed between ACLR groups. The pediatric ACLR group exhibited lesser knee abduction moment (KAM) compared to pediatric controls (11-35; 85-91%) and adult ACLR patients (14-92%). CONCLUSION: Pediatric ACLR patients demonstrated minor differences in vGRF and sagittal plane profiles but substantially lesser KAM loading than adult ACLR patients and may require developmentally-appropriate gait interventions post-ACLR.Research reported in this abstract was supported by the American College of Sports Medicine (22-01803), the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institute of Health (1R21AR067560-01) and the Arthritis Foundation.