Is it my knee cartilage?
This is a fairly general definition. Really, we should include the many components involved in dysfunction between patella and femur. Any of these can contribute to generating trouble and there are only a few cases where the problem cannot be corrected without surgery.Presenting symptoms may involve pain going down stairs or slopes (rather than going up), on holding positions in flexion, squatting, and walking on uneven ground. It is generally recommended to avoid such activities when someone suffers from this type of problem.
In many cases the onset of symptoms is related to a change in activity level, especially when taking up a sport again or increasing its intensity after a relatively long period of inactivity. Sometimes it can also occur when a new activity is begun.
All this can be explained: the muscles involved in the movement of knee extension (leg stretch) tell the patella (that little bone floating in front of the joint) to keep to the track which follows the shape of the femur.
These muscles are co-ordinated, with each pulling the right amount for the movement to occur with proper alignment. We’re talking about all the muscles of the quadriceps (everyone knows where they are, don’t they?), and particularly the vastus medialis (aka vastus internus) and the vastus lateralis (aka vastus externus).
We could alsomention othercontracting muscles which pullin one directionor anotherto producea vectorthat, under normalconditions, ensures thatthe movementis correct.
These pairs of muscles pull in one direction or the other, as a perfectly coordinated team. This smooth co-ordination may be affected in the circumstances outlined above (increased activity, taking up a new sport, etc). This is when discomfort may occur. One of the muscles with a tendency to become lazy is the vastus medialis of the quadriceps. It is very small and its main function is involvement in the final 15 degrees of knee extension. It has longitudinal and oblique fibres, the latter of which may fail more often, resulting in poor inward re-centring of the patella.
Well, let’s not generalise, every knee has its history,its past, its nature, but the key to successful recovery from problems with thisjoint complexis to reactivate the lazy muscle fibres… sometimeseven just reminding them oftheir functionis sufficient.
For this there are specific exercises that isolate the contraction of these muscle fibres. Your physiotherapist can teach you a full exercise regime for your knee problem.