To Do Or Not To Do (OKC exercises)?

Here is the next follow up posting for our current trends in anterior cruciate ligament (ACL) reconstruction management which first started on Mar 19 this year

Now that you have done your ACL reconstruction and in the middle of your rehab program and yet continue to experience muscle weakness, especially in your quadriceps. Sounds familiar, fret not as this is a fairly common scenario among most if not all ACL reconstruction patients.

Most if not all physiotherapists will be quite hesitant to introduce open kinetic chain (OKC) exercises as compared to closed kinetic chain (CKC) exercises for fear of putting strain on the ACL.

Open Kinetic Chain (OKC) exercises are performed typically where the foot is free to move. These exercises are sometimes non-weight bearing, with the movement occurring at the knee joint (like the leg extension exercise in the photo). The opposite are closed kinetic chain (CKC) exercises. An example would be doing a leg press when the feet are in contact with the foot plate or a simple squat.

However, for optimal results OKC exercises are essential when used as part of a comprehensive rehab program. Consider this, you would be required to perform an maximal isokinetic knee flexion/ extension (bending/ straightening) test at designated timelines while undergoing your rehab. Most patients are allowed to run after regaining 70% strength in their quads while some studies indicate that you will need at least 90% strength before you can return to your sport. In order for you to get the desired strength, you will need to do specific training and that will have to include OKC exercises.

Published evidence supports the use of OKC exercises as part of a comprehensive rehab program especially when undergoing an isokinetic test. The researchers had 2 randomized groups of ACL reconstruction patients, one group with CKC quads strengthening while the other group did OKC strengthening. Aside from these quadriceps exercises, the 2 rehab programs were identical.

Patients were assessed after 4 months of rehabilitation. Muscle strength, jump performance, and muscle activation were also assessed. The OKC group had significantly greater isokinetic quadriceps strength after rehab. There was no difference in hamstring strength, 1-repetition-maximum squat test, muscle activation, jump performance, and functional outcome. The researchers concluded that rehab with OKC quadriceps exercise led to significantly greater quadriceps strength compared with rehabilitation with CKC quadriceps exercise.

Come see us after your ACL reconstrction, we'll definitely help you return to sports.

Reference

Tagesson, S et al (2008). A Comprehensive Rehabilitation Program with Quadriceps Strengthening in Closed versus Open Kinetic Chain Exercises in Patients with Anterior Cruciate Deficiency. Am J Sp Med. 36: 298-307