The Relationship Between Preoperative Quadriceps Muscle Strength and International Knee Documentation Committee (IKDC) Scores at Six Months Post-Anterior Cruciate Ligament (ACL) Reconstruction

Introduction: Anterior cruciate ligament (ACL) injury is a common knee injury among athletes and active individuals, often requiring ACL reconstruction to restore knee stability and function. Postoperative rehabilitation plays a crucial role in recovery, with quadriceps strength being a key factor influencing functional outcomes. However, the extent to which preoperative quadriceps strength affects postoperative functional outcomes remains a subject of interest. This study aims to evaluate the relationship between preoperative quadriceps strength and functional outcomes, as measured by the International Knee Documentation Committee (IKDC) score, at six months post-ACL reconstruction. Material & methods: This cohort study was conducted at RSUP Prof. Dr. I.G.N.G. Ngoerah Denpasar, involving patients undergoing ACL reconstruction between February and December 2024. Preoperative quadriceps strength was assessed using a handheld dynamometer, and postoperative functional outcomes were evaluated using the IKDC questionnaire at six months postoperatively. Correlation and comparative analyses were performed to determine the relationship between preoperative quadriceps strength and postoperative IKDC scores. Results: The study included 22 patients with an average age of 31.77 ± 11.92 years. Pearson correlation analysis showed a significant positive correlation between preoperative quadriceps strength and IKDC scores at six months postoperatively (r = 0.426, p = 0.048). Furthermore, patients with a quadriceps strength deficit of more than 20% preoperatively had significantly lower IKDC scores postoperatively compared to those with a deficit of 20% or less (p = 0.042). Conclusions: Preoperative quadriceps strength is a significant predictor of functional outcomes following ACL reconstruction. Patients with greater preoperative quadriceps strength tend to achieve better functional recovery. These findings highlight the importance of preoperative rehabilitation focusing on quadriceps strengthening to optimize postoperative outcomes. Keywords: ACL reconstruction, quadriceps strength, IKDC score, functional outcomes, knee rehabilitation