Hip Arthritis

Hip arthritis is a generalized term to describe degeneration of the hip joint, most often the result of osteoarthritis. The hip is a ball-and-socket joint and, in degenerative conditions, either the ball (femoral head) and or the socket (acetabulum) may be involved. The most common symptom experienced by patients is that of pain in the hip. Specifically the pain may be located in the groin, along the front of the thigh, buttock, or even the knee. The discomfort is usually related to activity and more often feels like a dull ache. Patients my also experience pain at night. In addition to pain, symptoms such as stiffness and catching or locking may occur. As degenerative arthritis in the hip progresses, patients will experience more difficulty with daily activities such as walking, driving, standing from a seated position, golfing, gardening and even sleeping.

Avascular Necrosis

Avascular Necrosis (AVN) occurs because of temporary or permanent loss of blood supply to the ball of the hip joint (femoral head). This entity is known by various names (osteonecrosis, aseptic necrosis, and ischemic bone necrosis). Often the overlying joint surface collapses secondary to the loss of blood supply which can be a precursor to developing degenerative changes in the hip joint. Avascular Necrosis can occur after traumatic (hip dislocation) and non-traumatic episodes. Non-traumatic entities associated with AVN include alcoholism, chronic use of steroid medications (ie cortisone), radiation exposure, sickle cell disease, Gaucher disease, and systemic lupus erythematosus.

The symptoms usually begin as a painless bone abnormality which, with time, develops into pain with weight bearing activities. As the disease process progresses, the femoral head may collapse from degeneration of the underlying bone. At this point the patient can experiences symptoms such as pain with passive hip rotation as well as pain in the groin at rest. In cases where bone degeneration is present, the diagnosis can often be made with plain x-rays. In early stages, bone changes are not evident and an MRI or bone scan may be necessary to make the diagnosis.

Rheumatoid Arthritis

As opposed to osteoarthritis (wear and tear process), rheumatoid arthritis (RA) is caused by chronic inflammation in the hip joint and is therefore known as an "inflammatory arthritis". The cause of RA is not know although there seems to be an auto-immune component to this entity. Because of this inciting event, the synovial lining of the hip joint becomes inflamed which leads to the breakdown of articular cartilage lining the ball and socket. RA can effect multiple joints simultaneously (including the knees) and can also effect other internal organs. Patients experience symptoms such as pain and stiffness as well as swelling secondary to the inflamed synovial lining.

Diagnosis can be made by careful physical exam as well as the presence of a marker in the blood. There are features on x-ray specific to inflammatory arthritis conditions which are useful in distinguishing this process from osteoarthritis.