February 22nd, 2012Problems With The Hip Joint
The hip is regarded as a ball and socket joint. The ball element is named the femoral head, and is at the end of the thigh bone (femur). The socket is termed the acetabulum which is part of the pelvis. The joint surfaces that push towards each other are covered with a structure called cartilage which is lubricated with fluid; this permits the joint to move with no resistance. Encompassing the hip joint are the capsule, ligaments, muscles, fascia, nerves and blood vessels. There exists a structure referred to as labrum which attaches to the boney rim of the acetabulum which serves to deepen the socket and have a operate as a vacuum seal.
Femoral Acetabular Impingement (FAI)
The shape, size and form of the hip joint can differ from individual to individual. This may be from how we are genetically hard-wired, or how the hip joint develops as we go from childhood to maturity, or other reasons such as injury or pathology. Listed below, we have tried to simplify the distinct types of boney differences which could cause impingement, but it is necessary to understand that there can be different degrees of these and variations.
1.PINCER – This is when the boney rim of the socket (acetabulum) is covering more of the ball (femoral head) than in the average hip. A particular area of the socket is affected, and this results in ‘pinching’ of the hip joint structures when the hip joint moves, thus termed impingement. In a number of individuals, there is global overcoverage (involves the entire socket), and this is named Coxa Profunda.
2.CAM – This term refers to a boney lump that is present near the top of the thigh bone (femoral neck). This lump can make the ball of the hip joint less rounded, and and once the hip joint moves, this lump can chafe or catch against the hip joint structures.
3.CAM/PINCER MIXED IMPINGEMENT – Sometimes there may be overcoverage of the socket (pincer/coxa profunda) and in addition to this, the boney bump (CAM) on the femur.
Hip Dysplasia
This is a condition where the socket is not covering the ball (femoral head), sufficiently. There are different levels of this. Measurements called the ‘centre edge angle’ are taken from the xray to determine how much lack of coverage there is. Some sufferers are offered a specific operation by consultant Surgeons referred to as a peri-acetabular osteotomy (PAO) to help fix this.
Hip Labral Tears
The fibrocartilagenous labrum which encompasses the socket can at times be torn or become degenerate. There are different classifications of this and it can be triggered by various reasons including through injury or hip joint abnormalities such as FAI and dysplasia.
If you are affected by any of the injuries described in this article, you should consult your nearest hip arthroscopy physio.
By Louise Grant Physiotherapists Leeds