Longitudinal Changes in Kinesiophobia, Psychological Readiness, and Knee Function Across Anterior Cruciate Ligament Reconstruction Rehabilitation Phases

Background/Objectives: Anterior cruciate ligament reconstruction (ACLR) is a common orthopedic procedure; however, successful return to sport (RTS) remains a major challenge influenced by both physical and psychological factors. Kinesiophobia and psychological readiness are crucial yet inadequately studied components of rehabilitation that may change across distinct phases. This study aimed to examine longitudinal, phase-specific changes in kinesiophobia, psychological readiness, and patient-reported knee function across standardized ACLR rehabilitation phases. Methods: A retrospective longitudinal cohort design was employed. Data were extracted from 45 patients who completed ACLR rehabilitation at a specialized musculoskeletal center in Riyadh, Saudi Arabia. Participants were assessed across four rehabilitation phases: Phase One (0–1 month), Phase Two (>1–3 months), Phase Three (>3–6 months), and Phase Four (>6 months post-ACLR). Outcomes included the Tampa Scale of Kinesiophobia (TSK-17), the ACL–Return to Sport after Injury scale (ACL-RSI), and the International Knee Documentation Committee subjective knee form (IKDC), administered using validated Arabic versions. Linear mixed-effects models with Bonferroni-adjusted pairwise comparisons were used to evaluate phase-related changes. Results: Significant fixed effects of rehabilitation phase were observed for all outcomes (p < 0.001). Kinesiophobia declined substantially from Phase One (mean 51.5) to Phase Three (34.7), with the greatest reduction between Phases Two and Three, followed by stabilization in Phase Four. Psychological readiness increased progressively across all phases (ACL-RSI: 37.1 to 61.8). Knee function demonstrated the greatest improvement during late rehabilitation (IKDC: 37.6 to 75.8). Conclusions: Psychological and functional recovery following ACLR follow distinct temporal trajectories rather than improving synchronously. Kinesiophobia declines most markedly during mid-rehabilitation, while functional gains peak in late rehabilitation. These findings support integrating structured psychological screening into phase-specific ACLR rehabilitation protocols.