Knee functional outcomes and quadriceps hypotrophy after ACL reconstruction: a prospective observational study

ACL injuries are common among athletes and individuals experiencing trauma, leading to instability and functional impairments. Post-ACL reconstruction, patients often face challenges like pain and reduced knee function, impacting their daily lives and sports participation. The aim of this study was to describe knee functional outcomes of patients with ACL tears over three months through three subsequent visits.

This prospective observational study involved patients with ACL tears who were assessed pre-ACLR and at 1 and 3 months post-ACLR. Measures included Tegner Activity Scale, IKDC Subjective Knee Evaluation, Lysholm Knee Scoring Scale, pain scales, quadriceps thickness via ultrasound, and Rectus femoris and Vastus lateralis muscle activation via surface electromyography.

A total of 98 patients were included in the study. Significant improvements were observed in Tegner Activity Scale scores (p < 0.001), IKDC scores (p < 0.001), Lysholm scores (p < 0.001), and pain scores (p < 0.001) over the study period. Ultrasonography and surface electromyography revealed ongoing quadriceps muscle hypotrophy and reduced neuromuscular function, highlighting the need for targeted rehabilitation.

Structured rehabilitation post-ACL reconstruction significantly improves functional outcomes and reduces pain. Challenges like muscle hypotrophy and decreased activation post-surgery emphasize the need for targeted rehabilitation strategies in the initial stages of recovery. Tailored programs focusing on these early deficits are crucial for optimizing recovery trajectories, enhancing knee stability, and preventing long-term complications. Immediate attention to these issues can help refine rehabilitation protocols, ensuring more effective outcomes as patients progress through their recovery. Further research should also focus on the long-term sustainability of these improvements.