Having a stiff knee after surgery is completely normal.
Before working through the stiffness, depending on the stage of your rehab, it is best to see your physio so you can understand what might be causing the stiffness.
Early stage of ACLR rehab
Early on after surgery, contributing factors might include:
- Surgery Trauma: The surgical procedure itself can cause temporary inflammation and swelling in the knee joint
- Immobilization: Post-surgery, the knee is sometimes immobilized or restricted in movement to facilitate healing (for example, with a meniscus repair, the knee is limited in flexion until about 6 weeks post-operatively)
- Scar Tissue Formation: As the knee heals, scar tissue can develop, restricting the normal range of motion and causing stiffness
- Muscle Weakness: Muscles around the knee may weaken due to disuse during the recovery period, regaining strength in these muscles helps move joint through range to reduce the feelings of stiffness
- Pain: Patients may be cautious about moving the knee after surgery, which can lead to psychological apprehension and painful movements
- Lack of regular movement: the joints in the body are self-lubricating bringing fluid and nutrients to the joints when we move. When this motion is limited and we are now sitting more, or having our leg in a single position for longer periods of time, this doesn’t get to happen as naturally
How to treat knee stiffness in the early stage of ACLR rehab
You should always talk to your own physio about what exercises are right for you and your injury. This is general advice and examples from my own ACL experience and is not medical advice.
Tibial rotation – I found this movement to be limited in my early stages of my ACL surgery and is an easy exercise to implement
Knee CARS – this movement is a bit harder than just tibial rotation but can be still be modified to the level of recovery the knee is in
Completing your physio exercises! I found that doing hamstring sliders helped most with the stiffness into flexion, as well as, practicing controlled sitting back on my heels
Late stage ACLR rehab
Later on in the mid to later stages of the rehab process, stiffness can result from:
- Not moving the knee often enough, for example, some sort of exercise each day
- Doing a training session and then having a break before going again – for example, this happened when I would play soccer then take a break at half time and then head back on the field
- From doing too much heavy or fast training
How to treat knee stiffness in the late stage of ACLR rehab
Couch Stretch – this works on hip flexor and quad tightness while putting the knee in a very flexed position, part 2 of the exercise then works on hamstring inner range holds
Adductor stretch – our adductors cross our knee joint and I found that keeping the length in these muscles contributed to my knee feeling less stiff
Reverse nordics – this is actually a very hard exercise and I recommend using a band, but it helped with the quad strength and length to decrease pulling through the front of my quad
If you want more knee stiffness exercises, you can download my app Ripple, that has multiple exercises targeting knee mobility. The program is FREE For Ripple members.
![3 iphone screens showing the ACL injury pages in my app](https://hanphysio.com/website/wp-content/uploads/2024/07/all-things-acl-pages-2-1024x577.png)