Transient Osteoporosis of the Hip Overview

Transient osteoporosis of the hip is a condition that occurs for unknown reasons. The condition is characterized by a spontaneous onset of hip pain associated with X-ray signs of osteoporosis and MRI evidence of bone inflammation. The head of the thigh bone, the femur, loses bone density and strength. Transient osteoporosis of the hip usually resolves on its own within six months to a year. It is a very different condition from age-related osteoporosis.

Who Gets Transient Osteoporosis of the Hip?

Transient osteoporosis of the hip is usually found in middle-aged men and in women in their third trimester of pregnancy. It is not understood why these groups of patients are affected by transient osteoporosis of the hip. The cause of the condition is unknown, but theories include that the blood vessels in the area have been obstructed, there may be abnormal mechanical stress on the bone, or it relates to hormone changes.

Symptoms

The primary symptom of transient osteoporosis of the hip is the spontaneous onset of hip pain. You haven't had any injury that would explain why your hip is hurting. Pain may be experienced in the groin, buttock, or thigh. Usually, the symptoms are worse with weight-bearing activities. You may develop a noticeable limp. You may have limited motion as more extreme hip motions are more painful. The pain can get so intense that it is disabling. Pain tends to increase for a period of several months, and then gradually lessen with time.

Diagnosis

When the clinical symptoms raise suspicion of transient osteoporosis of the hip, an X-ray will be obtained. The X-ray will show osteoporosis of the femoral head (the ball of the ball-and-socket hip joint), which means the bone is less dense than normal. If this is seen, an MRI may also be obtained to look for the characteristic evidence of transient osteoporosis within this region. The MRI and X-ray can also be helpful to distinguish between other conditions which may have similar symptoms such as arthritis of the hip, avascular necrosis of the hip, or a femoral neck stress fracture.

Treatment

Because transient osteoporosis of the hip resolves within about 6 to 12 months on its own, treatment is aimed to decrease pain and discomfort. Because the bone is unusually weak in the affected area, there is a risk of hip fracture, which is the most feared complication of this condition. Your healthcare provider may recommend limiting weight-bearing activities and using crutches or a walker to decrease the stress on the bone.

Pain medications can be helpful to reduce the discomfort associated with this condition. Recent studies have also shown some benefit of bisphosphonate medications used to treat osteoporosis.

Physical therapy may be recommended to maintain your strength and flexibility. Water exercises can be good as they are non-weight bearing. It's good to get Vitamin D and calcium to support bone healing.

How It Differs From Age-Related Osteoporosis

Age-related osteoporosis is a progressive and usually painless condition that affects bones throughout the body. Age-related osteoporosis has long-term consequences and risks for fractures.