The aim of this study is to compare the knee function between patients with and without preoperative exercise habits at 1, 2 and 5 years after ACL surgery, and further analyze the effect of maintaining exercise habits on knee function and recurrence rate

Objective:

1. To compare the knee function between active and inactive patients at 1, 2, and 5 years after ACL surgery.
2. To investigate the difference of knee function and recurrence rate between patients with and without postoperative exercise habit.

Methods: This is a single-center, controlled follow-up cohort study. Inclusion criteria included patients aged 18-45 years with confirmed ACL injury who were scheduled to undergo ACL reconstruction surgery. Exercise habits were recorded before operation, and knee joint function and exercise level were evaluated by questionnaires. All patients received standardized ACL reconstruction surgery and rehabilitation program after surgery. In prospective cohort study, 121 patients were divided into running group and non-running group according to their preoperative exercise habits. At 3 months after surgery, running was included in the rehabilitation program, and the patients were further divided into postoperative running and non-running groups and followed up for one year.In Postoperative cohort study， follow-up was collected and evaluated at 1 year, 2 years and 5 years, including knee function, exercise level and recurrence. The study was divided into four groups: preoperative running group , preoperative non-running group , preoperative and postoperative running group and preoperative non-running and postoperative running group to analyze the effects of preoperative and postoperative exercise habits on knee joint function and recurrence rate. The results of this study will help to deepen the understanding of the impact of preoperative exercise habits and postoperative exercise maintenance on knee function and recurrence rate after ACL reconstruction, and then provide guidance for clinical practice, optimize postoperative rehabilitation programs, and ultimately improve the quality of life of patients.

Subjects: Patients with anterior cruciate ligament rupture in Department of Sports Medicine, Peking University Third Hospital 1.1.1 Inclusion criteria

1. Age of 18-45 years old, male or female.

2. Patients were diagnosed with anterior cruciate ligament injury and planned to undergo anterior cruciate ligament reconstruction surgery 1.1.2 Exclusion criteria Presence of other severe knee disorders (e.g., arthritis).

   • Prior history of other knee surgeries
   • Inability to complete a postoperative rehabilitation program or long-term follow-up.

Inclusion Criteria:

• Patients with anterior cruciate ligament rupture in Department of Sports Medicine, Peking University Third Hospital

Exclusion Criteria:

• Severe other knee disorders (e.g., arthritis) are present.
• Prior history of other knee surgeries
• Inability to complete a postoperative rehabilitation program or long-term follow-up

An ACL injury was diagnosed and an ACL reconstruction surgery was planned