Which intervention is inappropriate for a patient 5 weeks s/p ACL reconstruction?

• A. Open chain leg extensions between 60 and 30 degrees
• B. Closed chain exercises
• C. Progressive resistance exercises
• D. Isometric exercises

Answer: (A)

After an ACL reconstruction, the rehabilitation protocol typically prioritizes healing and restoring knee function while minimizing stress on the graft. Open chain leg extensions, particularly between 60 and 30 degrees of flexion, place significant strain on the knee joint, specifically the anterior cruciate ligament during the early healing phase. At 5 weeks post-surgery, the graft is still maturing and vulnerable, and exercises that involve isolated quadriceps contraction in this range can disrupt the healing process and possibly compromise the stability of the new ligament.

In contrast, closed chain exercises, such as squats or leg presses, are generally encouraged during this phase because they promote joint stability and functional movement patterns, engaging multiple muscle groups and allowing for better control of the knee joint. Progressive resistance exercises can be appropriate as long as they are carefully guided and monitored, ensuring they stay within safe ranges of motion and load. Isometric exercises are beneficial for maintaining muscle strength without placing undue stress on the knee joint, making them suitable for this stage of recovery.