Biomechanics of OsteoArthritic Knees and How an OA Knee Brace corrects it
The most common form Knee Osteoarthritis or OA knee is the pain on the inner side of the knee (or the medial side). This has to do with the fact that most of us are slightly bow-legged, not enough to be said bow-legged, but a slight bias toward it. The video below is quite lengthly but you can see this knee inward bend from the video starting from the position 1m:40s.
On why your knee bend inwards can be caused by a range of factor from poor foot bio-mechanics to tight buttock muscles (glutes) that rotate your hip outwards. As you can see from the video at 1m:55s onwards. the inner knee compartment (medial knee) has a lot less space between the thigh bone (femur) and the shin bone (tibia). From a process of wear-and-time over time, eventually inner side of the knee joint’s cartilage or meniscus gets worn away resulting in pain.
How an OA knee brace work to relieve OA Knee pains is to shift the knee such that the parts of the thigh bone and shin bone that touching and scraping against each other is pried apart. (see the video at 4m:00). When ‘pried apart’, the two bones stop scraping against each other, taking away the source of the pain.
In others, the knees lean inwards for what is known as ‘knocked knee’ (from the knee knocking against each other) the pain is felt on the outer side of the knee (the lateral side). In such cases, the OA knee brace works in the other direction along the same principle of separating the two bones that are scraping against each other.