Pain in the lateral part of the hip is a common symptom of consultation. The differential diagnosis must be made by the specialist in traumatology between intrarticular pain, extrarticular pain and referred pain of the lumbar spine. Lateral hip pain has been classically called trochanteritis. Currently, thanks to a better anatomical knowledge and tests such as magnetic resonance imaging (MRI), we speak of peritrochanteric pain or Greater Trochanteric Pain Syndrome (GTPS). This pathology includes different alterations in the lateral region of the hip, around the greater trochanter, including trochanteric bursitis, tendon lesions of the gluteus medius and gluteus minimus, and spring hip.
Location of the greater trochanter and lateral hip pain
The greater trochanter is the part of the femoral bone at the junction between the neck and the diaphysis. The gluteus medius inserts into it laterally and posteriorly and the gluteus minimus anteriorly. These are covered by the gluteus maximus, the tensor fascia lata and the ileotibial band, which extends along the lateral aspect of the thigh to below the knee.
Between these muscle groups are located the bursae (most frequently 3 but can be 4). The largest is located between the gluteus maximus and the gluteus medius tendon (trochanteric bursa), the other two below the gluteus medius and below the gluteus minimus.
- Trochanteric bursitis is the inflammatory condition around the greater trochanter, usually radiating to the lateral thigh or buttock. It usually originates as a consequence of repetitive hip flexion and extension movements, due to friction between the ileotibial band and the greater trochanter. It is more frequent in women than in middle-aged men. It presents as pain in the lateral aspect of the hip, with pain in the greater trochanter and increases with abduction against resistance. Plain radiography is usually normal but intrarticular pathology should be ruled out. Calcifications around the trochanter may be detected, but are nonspecific.
Magnetic resonance imaging (MRI) can demonstrate inflammation of the bursae and rule out tendon pathology of the gluteal musculature. Generally, trochanteric bursitis is self-limiting and usually responds to rest, anti-inflammatory treatment, local ice and physiotherapy. If this is not sufficient, infiltration with corticosteroids and local anesthetic is usually effective in most patients. Infiltration is more effective in the short term, while physiotherapy with stretching seems to be more effective in the long term. In exceptional cases surgery, open or endoscopic, may be indicated. - Tendinopathy of the gluteus medius and gluteus minimus are lesions of the tendons of the hip abductor musculature that have been equated with the rotator cuff of the shoulder. In cases of peritrochanteric pain, thanks to MRI, lesions of the tendons of the gluteus medius and gluteus minimus are diagnosed, ranging from tendinitis (inflammation) and tendinosis (degeneration) to partial ruptures or complete ruptures. Such injuries are more frequent in the gluteus medius than in the gluteus minimus.
Although the debut of the symptoms may be of traumatic origin, in most cases it presents in an insidious and non-traumatic manner. In addition to pain in the lateral aspect of the hip and trochanter, the patient presents weakness to abduction in extension and external rotation with 90º hip flexion. Pain may also be reproduced when maintaining monopodal loading on the affected side for 30 seconds or more. The best performing diagnostic test is MRI, which can distinguish between partial and total ruptures, and allows assessment of possible fatty degeneration of the musculature.
Patients with gluteus medius tendon injuries may show a thickening of the tensor fascia latae on MRI, compared to the contralateral one. The initial treatment of this pathology is conservative, with rest, anti-inflammatory drugs and physiotherapy to strengthen the musculature. Surgical treatment is exceptional, in very limited cases. The repair can be done by open approach or endoscopy. - Spring hip or coxa saltans is described as the audible and potentially painful protrusion of the hip in activities that require flexion, extension and abduction. With the hip in extension, the ileotibial band is located posteriorly on the greater trochanter, when flexing the hip the ileotibial band slips over the trochanter. Occasionally this protrusion can cause inflammation and pain. It usually occurs between late adolescence and the second decade of life. X-ray is usually normal, ultrasound, being a dynamic test, can visualize the protrusion and whether there is associated bursitis. Treatment is usually conservative, with stretching and muscle strengthening. Rarely the treatment is surgical, with multiple techniques described, both for open surgery and endoscopic technique.