Open Kinetic Chain (OKC) exercises such as knee extensions are often demonised because of the potential to stress the surgical graft following an ACL reconstruction.
The benefits of knee extensions in post ACL reconstruction.
Knee extensions are an amazing exercise for isolating and building quadriceps strength, and there is plenty of research that backs their use of them in rehab. Knee extensions are in fact probably one of the most important exercises to progress throughout your rehab. The exercise can help build isolated quadricep strength and bulk, and it is quite easy to set up and monitor progression. To put it short, when it comes to strengthening the knee, the quads are definitely a huge priority!
The Clinical Practice Guideline published by Van Melick et al., 2016 is a great summary of the available literature on this topic. It provides great recommendations on the timing, and range of motions necessary to reduce risk of re rupture. The recommendations are as follows:
- For ACL reconstructions with a bone-patellar tendon-bone (BPTB) autograft, knee extensions can be started from 4 weeks post op with a restricted range of motion (ROM) of 90–45°, and extra resistance is allowed to be added.
- For ACL reconstruction with a Hamstring graft, OKC exercises like knee extensions can also be started from 4 weeks post op with a restricted range of motion (ROM) of 90–45°. However, no extra weight should be added in the first 12 weeks to minimise risk of graft elongation.
- For both grafts, ROM can increase to 90–30° in week 5
- In week 6, ROM can increase to 90-20° for both grafts
- In week 7, ROM can increase to 90-10° in for both grafts
- Full ROM is allowed from week 8 onwards
When it comes to loading for this exercise, it is important to progress gradually week by week and listen to your body! If your knee is sore or swollen after a workout, this is an indicator that it isn’t tolerating the volume or load you are doing!
If you are looking for a guided rehabilitation approach for whatever knee injury you are carrying, contact our sports physios for an evidence-based assessment and treatment plan.Speak to a Physio