In my ankle blog, I wrote about injuries that will impact ankle mobility if not correctly rehabilitated. As with all mobile joints, if the joint becomes immobile, stiff or restricted, the body will adapt and begin to access the mobility it needs from elsewhere. In the ankle’s case, the knee will start to help.
The help is ok in the short term; the knee can take a little rotation, but its primary design is to hinge and provide stability. Over more extended periods, however, ankle or hip, restrictions could play havoc with the knee and lead to chronic knee pain.
Strength and stability
The knee is a strong joint, and it is one of the body’s shock absorbers. It is stabilised by strong ligaments that maintain its alignment. The meniscus, a spongier type of cartilage, provides a lot of shock absorption. Cartilage is sandwiched between the upper and lower leg bones, ensuring smooth gliding surfaces to protect the bone. Filling the gaps is synovial fluid, one of the body's essential lubricants, which reduces our joints wear and tear.
I shall distinguish here between pain and injury.
Knee injuries typically include tears to the ligaments or cartilage, the most common of which is an anterior cruciate ligament, or ACL, tear or rupture usually caused by extreme twisting or the knee bending the wrong way. Meniscus cartilage tears are common and generally caused by sudden force or twisting or just old age through wear and tear.
Knee pain, as suggested earlier, could be related to other joints, namely the ankle or hip. If the knee is only meant to hinge but asked to do more because the ankle or hip is dysfunctional, it will start to complain. It is easy to blame the knee because you may not have any discomfort in your hip or ankle or may not be aware that movement is restricted. The hip and ankle are such mobile joints. Even a small restriction could be the real root cause of your knee pain; it is the symptom that something is not well in the movement system.
I say system here as it is not uncommon for upper back stiffness to cause downstream problems. Similarly, if you have tight leg muscles (hamstrings, quads, calves, tibialis and soleus) or even weakness, these can contribute to knee pain, as most of these cross over the knee to assist with its natural hinging movement pattern. Tight quads, specifically, can cause the kneecap to pull up or to the side, as the muscle tendon attaches directly to the patella.
Assessment and maintenance
In my humble opinion, knee pain can only be adequately diagnosed by assessing movement patterns and identifying areas of dysfunction. After all, if you have a problem with upper back, hip or ankle mobility, merely looking at the knee and prescribing exercises for the knee will have little long term benefit.
If you are recovering from a knee injury, it is also likely that physical adaptations have occurred, resulting in imbalances and, therefore, a need to remap movement patterns and rehabilitate to account for those adaptations to ensure complete recovery and reduce future occurrences. Because without that approach, they inevitably will.