Blogs from March, 2023

holding knee

Surgery to repair a torn ACL is very common, with approximately 100,000 performed each year in the United States. With the rate of surgery so high, many people might not realize that there are some people who function very well with a torn ACL that is not repaired. These people are termed “copers”. Copers are defined as patients that can return to their preinjury activities without episodes of giving

way or instability and do not require surgery. Kaplan1 suggested that all patients with torn ACL’s undergo rehabilitation – either as pre-operative rehabilitation or as rehabilitation to dynamically stabilize the knee and potentially avoid surgery. Patients who will eventually have ACL surgery benefit from rehabilitation prior to surgery as they progress more easily through the postoperative rehabilitation and regain their range of motion easier2. Some of the patients that were doing pre-operative rehabilitation ended up being able to regain dynamic stabilization of their knee and decided to not have surgery1. The rehabilitation of these 2 groups is similar.

  • Reduce swelling and inflammation with rest, ice, compression, elevation
  • Protect the knee with a brace, while muscles are inhibited due to recent injury and swelling
  • Restore normal range of motion in the knee
  • Maintain or gain strength in the muscles of the knee, hip and core
  • Perturbation training – a type of balance training where the patient has to react to unpredictable forces. This type of training improves dynamic stability.


  1. Kaplan Y, Identifying individuals with anterior cruciate ligament-deficient knee as copers and noncopers: A narrative literature review. J Orthop Sports Phys Ther 2011; 41(10): 758-766.
  2. Wilk KE, Macrina LC, Cain EL, Dugas JR, Andrews JR. Recent advances in the rehabilitation of anterior cruciate ligament injuries. J Orthop Sports Phys Ther 2012; 42(3): 153-171.