Overview

 

Hip osteonecrosis, also called avascular necrosis, impairs the blood supply to bone. Hip osteonecrosis occurs when there is an interruption of the blood supply to the head of the femur (the ball, of the ball-and-socket hip joint). The lack of normal blood supply causes a decrease in delivery of oxygen and nutrients to the bone, and the bone subsequently dies. When the bone dies, the strength of the bone is greatly diminished, and the bone is susceptible to collapse.

Osteonecrosis of the femoral head involves the hip joint, with osteocytes of the femoral head dying along with the bone marrow; resorption of the dead tissue by new but weaker osseous tissue can then lead to subchondral fracture and collapse. There are 2 forms of osteonecrosis: traumatic (the most common form) and atraumatic. Other terms to describe this disorder are avascular necrosis and ischemic necrosis to denote vascular etiology. The term aseptic necrosis also has been used to indicate that infection does not play a causative role.

Causes of Osteonecrosis

Osteonecrosis or death of bone may occur after an injury or fracture blocks the blood supply to an area of a bone. Studies have suggested that this type of osteonecrosis may develop in about 20 percent of all people who dislocate their hip joint. Minor injuries will not result in osteonecrosis.

The term osteonecrosis is the term used to describe bone dying ("osteo" meaning bone and "necrosis" meaning dying). In osteonecrosis of the hip there is an interruption of the blood supply to the head of the femur. Without blood, the bone that forms the head of the femur and the articular cartilage that covers it can not get the nutrients that they need. The bone eventually dies. The head of the femur can lose its strength and collapse. The articular cartilage also breaks down.

What causes the blood supply to the head of the femur to be interrupted is not clear. It seems to occur more often in people aged 20 to 50 and in people with certain chronic (long term) medical conditions.

Other risk factors for osteonecrosis of the hip include:



Long-term corticosteriod use may also cause osteonecrosis to form. Corticosteriods are used to treat inflammation in diseases, such as rheumatoid arthritis. Doctors are not sure why long-term use of corticosteriod puts people at a higher risk. If you are concerned, talk to your doctor about your particular situation.

Excessive alcohol use is also a common cause of osteonecrosis. Other diseases, such as kidney disease, lupus and blood disorders, are also risk factors for developing osteonecrosis. However, in approximately 30 percent of osteonecrosis cases, the cause is unknown.



What are the symptoms of hip osteonecrosis?

Hip osteonecrosis usually has few warning signs. Patients often complain of new onset hip pain and difficulty walking.

Common symptoms of hip osteonecrosis include:




There are several surgical treatment options for osteonecrosis, including:

Core decompression -This simple procedure works best in cases that are mild and before the collapse of a joint. A hole is created and a thin layer of bone is removed. This reduces pressure within the bone while increasing blood flow to the bone.

Bone grafting – After a core decompression, a bone graft may be used to support a joint. In this complex procedure, healthy bone is transplanted from one part of the body to the diseased area. The dead bone is removed and a bone graft is put in its place. Crutches and/or walkers will need to be used for up to a year to help the healing process.

Osteotomy – This uncommon procedure has a lengthy recovery period and is used in advanced cases and for those patients with a large area of affected bone. The bone is cut below the infected area and turned so that another portion of the bone that is not affected by osteonecrosis is the new weight-bearing area.

Total hip replacement/Arthroplasty – If the hip joint is destroyed or the hip socket is affected, a total hip replacement may be necessary. In this procedure, the diseased hip joint will be completely replaced with an artificial hip. Once the disease has progressed to the point the hip socket is affected, a total hip replacement may be necessary. Different types of hip replacements are available. You should talk to your doctor about your specific needs.



What are the treatments of hip osteonecrosis?

Treatment of hip osteonecrosis is difficult because the problem tends to progress quickly despite intervention. In the early stages of hip osteonecrosis, crutches and anti-inflammatory medications can be helpful.

Surgical options in the early stages of hip osteonecrosis include hip decompression and vascularized bone grafting. Hip decompression is done to relieve increased pressure within the femoral head. This pressure build up may contribute to the problems with blood supply. A hip decompression is done with the patient asleep in the operating room. Small holes are drilled into the area of hip osteonecrosis to relieve the pressure within the femoral head. The vascularized bone graft moves healthy bone from the lower leg (along with the blood vessels attached to the bone), and places this into the area of hip osteonecrosis. The goal of this surgery is to deliver normal blood flow to the affected hip. Both of these procedures are done only in the early stages of hip osteonecrosis.

The most common surgical treatment of hip osteonecrosis is total hip replacement. If there is damage to the cartilage of the joint, then hip replacement is probably the best option. While hip replacement works well, the replacements will wear out over time. This presents a problem in young patients diagnosed with hip osteonecrosis. Another option for younger patients is called hip resurfacing surgery. This procedure is similar to a standard hip replacement, but removes less normal bone.

For more information, medical assessment and medical quote

as email attachment to

Email : - info@wecareindia.com

Contact Center Tel. (+91) 9029304141 (10 am. To 8 pm. IST)

(Only for international patients seeking treatment in India)