This study aims to investigate the improvement effect of visual-guided balance training on the knee joint function and gait performance of patients after ACLR, and to clarify the advantages of this training program compared to conventional rehabilitation training; at the same time, by including healthy individuals as the control group, it quantifies the differences in knee joint function and gait performance between patients after ACLR and healthy individuals, to verify whether visual-guided balance training can more effectively narrow the functional gap between patients after ACLR and healthy individuals, and promote the recovery of patients' knee joint function and gait closer to the healthy level. Ultimately, it provides scientific theoretical basis and practical guidance for the optimization of the rehabilitation plan after ACLR, and helps patients achieve comprehensive and high-quality recovery.

In this randomized controlled clinical study, patients with primary unilateral anterior cruciate ligament rupture were included. Starting from the 5th week after surgery, in addition to the standardized rehabilitation training content, the traditional group added general balance training, and the intervention group added visual guidance balance training. The analysis was conducted through movement function tests and evaluations, with the healthy group included as the control. The impact of visual guidance balance training on the movement function and biomechanical characteristics after ACLR was explored.

Inclusion criteria for patients:

1. Age between 18 and 45 years old;
2. Body Mass Index (BMI) ranging from 18.5 kg/m² to less than 35 kg/m²;
3. First unilateral ACL rupture and reconstruction surgery performed at this hospital;
4. Autologous hamstring tendon transplantation;
5. No or only minor injury to the meniscus, posterior cruciate ligament, medial collateral ligament or lateral collateral ligament;
6. Voluntary participation in this study and signing of informed consent form.

Exclusion criteria for patients:

1. Patients who underwent ACL reconstruction more than one year after the injury;
2. Patients with severe injuries to the posterior cruciate ligament, medial collateral ligament or lateral collateral ligament (more than grade I; grade II is partial tear, thickening and tortuosity of the ligament, partial fiber interruption, and swelling of the surrounding soft tissues; grade III is complete rupture). ； Combined with severe meniscus tear;
3. Has a history of previous knee surgery, such as meniscus repair, ligament reconstruction, joint replacement, joint cleaning, etc.;
4. Has other knee joint diseases, such as: knee osteoarthritis, knee joint tumor, rheumatoid arthritis, tuberculosis, knee joint infection or inflammatory diseases, fracture, dislocation or other bone injuries, etc.;
5. Severe heart, lung, brain diseases or liver and kidney dysfunction, and visual and cognitive impairments.

Inclusion criteria for the healthy control group

1. Age 18-45 years old;
2. Body Mass Index (BMI) ≥ 18.5 kg/m2 and < 35 kg/m2;
3. No surgical history, injury history, or chronic joint diseases of the lower extremities;
4. No visual, cognitive impairments or neurological diseases;
5. No trauma or diseases that cause abnormal gait. Exclusion criteria

1. Poor compliance of the subject; 2. The subject withdraws the informed consent form; 3.The subject requests to terminate the study or is unable to complete all the trials for some reason; 4. The investigator believes that the subject's continued participation in the trial may cause significant adverse effects on their physical condition; 5. The ethics review committee decides to terminate the trial.