Tendonitis, tendinopathy, and rupture of the gluteus tendons are causes of hip pain and are often associated with trochanteric bursitis. Three hip muscles are called glutes: maximum, medium and minimum. The following figures show these muscles from a lateral view of the right hip, with skin and subcutaneous fat removed.
The gluteus muscles are the most required during gait (walking) and running, being responsible for maintaining the balance of the pelvis and trunk. The gluteus maximus muscle also plays an important role in hip extension. The gluteus medius and minimalis muscles are known as hip abductors, since they abduct (“open the hip”) when activated without leg support.
Despite the importance of these muscles in walking and physical activity, they are often “forgotten” in muscle strengthening activities. Even professional athletes often have gluteal muscle weakness and do not perform reinforcement exercises. The functional deficiency of these muscles alters the forces on the hip and overloads the hip joint and adjacent joints.
Tendonitis and ruptures usually affect the tendons of the gluteus medius and minimal muscles. As with shoulder rotator cuff tears, injuries vary in extent and may lead to fatty tissue replacement in cases of chronic rupture. Most of the gluteus tendon ruptures are chronic and probably related to tendon degeneration. Some cases have a mechanism of acute trauma, such as abrupt movements and accidents.
Lesions of the gluteus tendons cause lateral hip pain and weakness in abduction force. Direct pressure on the hip tendons usually intensifies the pain. Despite the clinical presentation similar to trochanteric bursitis, symptoms are usually more intense and longer lasting in cases of rupture of the gluteus tendons. However, trochanteric bursitis is often associated with injuries to the abductor tendons.
The size of the tendon rupture is not directly related to the intensity of the symptoms. As with shoulder tendons, small tears are often more painful than extensive tears.
Lateral hip pain is not exclusive to tendon injuries and trochanteric bursitis, and may be a consequence of intra-articular problems, external hip protrusion, tumor metastases and other diseases. Therefore, diagnostic approach should include all hip layers.
Clinical examination is the basis for the diagnosis of abductor tendon tears. Radiographs are required to exclude some diseases. Ultrasonography, computed tomography and magnetic resonance imaging may be indicated to confirm the diagnosis, rule out other diseases and guide treatment. Tests may also show neighboring muscle hypertrophy to compensate for glute function. Anesthetic infiltration of the trochanteric region and tendon insertion is also helpful in some cases.
Non-surgical treatment of abductor tendon injuries is successful in most patients, including the use of medications, physical therapy, and infiltrations. Conservative measures used to treat trochanteric bursitis are also useful for tendon injuries. Surgical treatment is indicated in the minority of patients with symptoms refractory to conservative treatment and reduced function. The surgery involves removal of the trochanteric bursa and repair of the injured tendons with the insertion of anchors. Surgery can be performed in a traditional way, called open or by video arthroscopy (endoscopy). In some cases of extensive ruptures tendon repair may be impracticable and muscle transfer techniques may be required.