The myriad etiologies that can result in posterolateral hip pain and the inherent difficulties involved in diagnosing the pain generator have led to the term greater trochanteric pain syndrome (GTPS) supplanting trocahteric bursitis. Between 10% and 20% of adults report persistent hip pain, with the prevalence of GTPS increasing to between 20% and 35% in people with LBP. Inflammation of the bursal structures at the lateral hip was once proposed to be the sole etiology in the condition, but imaging and histological evaluations have demonstrated that this accounts for only a minority of cases. It is now recognized that other conditions, such as gluteal tendinopathy and small muscle tears, account for a large percentage of greater trochanteric pain syndrome.
The term ‘greater trochanteric pain syndrome’ (GPTS) may better characterize the condition because pain and reproducible tenderness in the region of the greater trochanter, buttock or lateral thigh, may be associated with myriad other causes such as tendinitis, muscle tears, trigger points, iliotibial band disorders (ITB), and general or localized pathology in surrounding tissues. GTPS, which to some extent has already replaced trochanteric bursitis as the most frequent designator for chronic lateral hip pain in light of the inherent difficulties in elucidating the true etiology of symptoms, can most accurately be described as a regional pain syndrome that often mimics pain generated from other sources, including, but not limited to, myofascial pain, degenerative joint disease, and spinal pathology.
Bursae are fluid-filled sacs that provide cushioning between bony prominences and the surrounding soft tissues. Overlying the lateral aspect of the greater femoral trochanter, the trochanteric bursae are commonly implicated as a cause of lateral hip pain. Four bursae have been consistently described outside the greater trochanter, with three being present in most individuals. These bursae serve to provide cushioning for the gluteus tendons, ITB and tensor fascia latae.
The gluteus minimus bursa is a minor bursa located cephalad and ventral to the greater trochanter. The two major bursae are the subgluteus maximus and subgluteus medius bursae. The subgluteus maximus bursa is located lateral to the greater trochanter, juxtaposed between the gluteus medius tendon and the gluteus maximus muscle. This largest of the greater trochanteric bursae is most frequently incriminated in GTPS.
Many risk factors have been associated with GTPS, including age, female gender, ipsilateral ITB pain, knee OA, obesity, and LBP. Because trochanteric bursitis can result from friction between the bursae and greater trochanter, it frequently occurs with overuse or trauma, especially falls. However, misdiagnosis is
Conditions other than actual bursal inflammation and gluteal tendinopathy that may result in lateral hip pain include gluteus medius muscle dysfunction, ITB syndrome, meralgia paresthetica, OA, and lumbar spine disorders.
Specific etiologies of GTPS include repetitive activity, acute trauma, crystal deposition and infection, especially tuberculosis. When an inciting event can be identified, the initial pathology usually occurs at tendinous attachments to the greater trochanter, with secondary involvement of adjacent bursae. In cases of acute trauma or the presence of other risk factors, extra caution should be exercised so that a more serious condition, such as femoral neck stress fracture or avascular necrosis.
Greater trochanteric pain syndrome typically presents as chronic, persistent pain in the lateral hip and/or buttock that is exacerbated by lying on the affected side, with prolonged standing or transitioning to a standing position, sitting with the affected leg crossed and with climbing stairs, running or other high impact activities. Approximately, 50% of patients experience pain radiating along the lateral aspect of the thigh to the knee, and occasionally below the knee. Invariably, there is tenderness along the lateral or posterior aspect of the greater trochanter. Pain extending to the groin or down the lateral thigh that mimics lumbar disc herniation (i.e pseudoradiculopathy) may be reported by some individuals. Pain radiation patterns may complicate the diagnosis of GTPS because of anatomical overlap with the iliotibial tract and mid-lumbar dermatomes (L2–4). Not only nerve roots, but radiation patterns from other structures in the lumbar spine, including the facet joints, sacroiliac joint, and intervertebral discs and ligaments, can replicate trochanteric bursitis/ GTPS.
In addition, damage to the nerve supply of surrounding structures may elicit neuropathic symptoms that can simulate GTPS. These nerve structures include the inferior gluteal nerve, which innervates the gluteus maximus muscles and is formed from the ventral rami of spinal nerves L5–S2, and the superior glutealnerve, which derives from the L4–S1 nerve roots and innervates the superior aspect of the femoral neck, tensor fascia lata, and the gluteus medius and minimus muscles. Regional pain syndromes, such as tendinosis and tears of the gluteus medius or minimus muscles, must also be considered in the differential diagnosis.
The physical examination in trochanteric bursitis/ GTPS characteristically reveals point tenderness (“jump sign”) in the posterolateral area of the greater trochanter. Typically, this will be at either the site of the gluteus medius tendon insertion or in a more cephalad position overlying the insertion of the gluteus minimus tendon on a ridge lateral to the anterior triangular area of the greater trochanter.
Pain reproduction can be accomplished by active resistance to abduction and external rotation, and sometimes by internal rotation. Rarely is pain reproduced by hip extension. In contrast, intraarticular hip disease is frequently characterized by pain elicited with flexion and extension of the hip.
Causes of lateral hip pain, such as ITB syndrome and meralgia paresthetica can be differentiated from trochanteric bursitis by physical examination signs, such as a positive Ober’s test and sensory deficits, respectively. Apart from point tenderness at the lateral hip, there are a paucity of signs with high specificity for GTPS.
Most cases of GTPS are self-limiting and tend to resolve with conservative measures, such as nonsteroidal antiinflammatory drugs, ice, weight loss, physical therapy, and behavior modification that aim to improve flexibility, muscle strengthening and joint mechanics while decreasing pain. These modifications and alternative activities that decrease precipitating motions but allow patients to remain active may speed recovery.
When conservative treatments fail, bursa or lateral hip injections performed with corticosteroid and local anesthetics have been shown to provide pain relief, with response rates ranging from 60% to 100%. Although there are no placebo-controlled trials evaluating the efficacy of corticosteroid injection therapy, several prospective studies have been published.
Symptom persistence after corticosteroid and local anesthetic injection may indicate other etiologies, including other bursae involvement, tendonitis, misdiagnosis, inaccurate needle placement, or recurrence of symptoms. In patients who obtain short term relief from local anesthetic infiltration, but fail to experience long-term benefit from the corticosteroid, the possibility of a noninflammatory contributor, such as peripheral or central sensitization, should be entertained.
When recurrence of lateral hip pain develops after a previous strong response, injections may be repeated with similar effect. In patients who fail conservative treatment, surgical intervention has been advocated. This recalcitrant trochanteric bursitis can sometimes be addressed with arthroscopic bursectomy and/or ITB release.