Effects of blood flow restriction training on knee function recovery after knee ligament surgery

INTERVENTION: BFRT + Conventional Training Group:Blood Flow Restriction Training combined with Conventional Training;Conventional Training Group:Conventional Rehabilitation Training; CONDITION: early disuse muscle atrophy and limitation of knee joint motor function. PRIMARY OUTCOME: Quadriceps peak torque to body weight ratio; SECONDARY OUTCOME: Y‐Balance;Quadriceps muscle circumference;Visual Analogue Scale (VAS) for pain;Knee joint range of motion;Lysholm knee scoring scale; INCLUSION CRITERIA: 1. Subjects aged between 18 and 50 years old; 2. 2 to 4 weeks post‐operation, unilateral anterior cruciate ligament (ACL) rupture, treated with arthroscopic‐assisted ACL reconstruction (ACLR); 3. The graft is the gracilis or semitendinosus tendon of the affected knee; patients with concurrent meniscus injury undergoing meniscoplasty or meniscal repair; 4. Knee flexion range of motion is 0°‐90°; 5. Significant reduction in thigh circumference on the affected side post‐operation, accompanied by quadriceps atrophy; 6. Normal mental and cognitive function, able to cooperate with rehabilitation training and follow‐up; 7. No foot and ankle joint symptoms such as flat feet (pes planus) or high arches (pes cavus); 8. Voluntary participation with signed informed consent form.