Do you suffer from knee pain?
Most people are unaware that the seemingly simple hinge joint of the knee actually comprises of three different joints which all need to move and glide well in order for the knee joint to function optimally as a whole.
The first of these is the patella femoral joint. i.e where the knee cap articulates with the femur. It’s quite amazing to consider that the knee cap needs to be able to glide about 15cm in an up/down direction as the knee bends and straightens! It’s also responsible for being a lever over which the quadriceps muscle works to straighten the knee as well as increasing the surface area over which loads are dispersed over the knee. So it follows that pain and problems arise when the joint is either stiff or simply genetically predisposed to injury by the patella being very small relative to the surrounding structures or situated very high on the femur. This is known as patella alta.
The hinge joint is known as the tibio-femoral joint because of the two bones which comprise it. This is the main weight bearing joint of the knee. There are half moon shaped cartilage called menisci which aid shock absorption in the compartments of the knee. These are prone to wear and may even tear if sufficient load is placed on them. This can be a one off incident (normally a rotational force) or over time e.g repetive rotational strain in a golfer’s knee. Normally the medial (inner side) meniscus is affected.
There are 4 ligaments that are crucial to keeping the knee stable. The anterior and posterior cruciate ligaments (ACL and PCL) and the medial and lateral collateral ligaments (MCL and LCL). These are normally more prone to be injured in a traumatic incident e.g a tackle in rugby. Depending on the severity of the ligament strain (this can be graded from grade 1, no failure of tissue to grade 4, a complete tear of the tissue) the physio along with a medical practitioner usually, will opt either for conservative management in a brace for a period of time or may decide it’s a case for surgery. This is normally done arthroscopically and has a varying rehabilitation protocol depending on what is found in the MRI scan and under examination.
There is also a small articulation between the tibia and the fibula (the two bones of the lower leg). This comprises the third joint of the knee and is vital for stability as it plays a role in the locking and unlocking mechanism during gait.
It must be said that the whole lower limb works in a chain and the successful rehabilitation of the knee depends hugely on the stability of the pelvis and core but also the strength of the glutes (buttock muscles) and quads (thigh muscles). Therefore in conservative management or post-op, glute and core exercise will comprise a major part of the clinic and home program.