Digital Rehabilitation Monitoring Reveals Critical Recovery Patterns After ACL Reconstruction: A Longitudinal...

Background: Despite the high prevalence of anterior cruciate ligament (ACL) surgeries, standardized, evidence-based rehabilitation protocols remain lacking. Digital medical devices (DMDs) like the "Orthelligent" system have gained relevance as adjuncts to traditional physiotherapy, offering continuous, objective monitoring of functional recovery. Methods: A retrospective cohort analysis included 335 patients who underwent ACL reconstruction and used the "Orthelligent home" system between August 2022 and December 2024. In total, 5675 recorded test and exercise events were analyzed. Functional recovery was assessed using the Limb Symmetry Index (LSI) across five defined rehabilitation phases (0-4). All patients followed a structured rehabilitation program aligned with current clinical practice guidelines, supplemented by Orthelligent as a home-based digital tool for daily monitoring. Results: Significant functional improvement was observed during early rehabilitation phases, with the LSI increasing from 0.64 ± 0.02 in phase 0 to 0.81 ± 0.01 in phase 2 (p < 0.001). Time since surgery was a significant positive predictor (p = 0.034), while pain showed a strong negative impact on performance (p < 0.001). Anthropometric factors had no significant effect. Exercises associated with high rates of drop-out, pain, or difficulty were identified and linked to specific rehab phases. Conclusions: This study demonstrates that digital rehabilitation monitoring can reliably reflect patient progress after ACL reconstruction. The early postoperative period (first 3 months) is critical for functional gains, highlighting the need for individualized, pain-sensitive rehabilitation strategies.