By Associate Professor Mark Arnold for Australian Doctor
8 March 2016
Vicki, 62 years old, has persistent right buttock pain present for six years. It interferes with sleeping on her right side, squatting and standing up from a low chair.
She experiences pain when ascending stairs and limps towards the end of the day. Her daughter mentions she has been lurching when walking for several years.
Her past history includes obesity (BMI 34.6), type 2 diabetes, hypertension and hyperlipidaemia.
Physical examination reveals she walks with a Trendelenburg's gait, has a positive Trendelenburg's sign on right-sided single leg stance, with tenderness over the right, and less on the left, trochanteric bursa, right iliotibial band and posterior iliac crests. Spinal motion is normal for age and painless on positioning. There are no dural tension signs evoked and neurological evaluation is normal. Hip motion is symmetrical and of normal range, but she has weakness and pain with hip abduction and external rotation.
Vicki was prescribed medications that were unhelpful or had side-effects — including paracetamol, amitriptyline, gabapentin and tramadol. She had numerous unsuccessful sessions of passive physical therapy of her back and buttock musculature. Acupuncture and alternative physical approaches were unsuccessful.
Spinal imaging demonstrates osteoarthritis of the L4-L5-S1 facet joints bilaterally. Radiologically guided corticosteroid injections and facet denervation procedures are performed several times without lasting success. An MRI demonstrates marked swelling of the right greater trochanteric bursa, with gluteus medius tendinosis and a tear of the gluteus medius and minimus.
Further radiological and non-radiological-guided corticosteroid injections in the region of the trochanteric bursa provide transient benefits.
Vicki's pattern of pain and limp has been evident over many years. Her symptoms and signs typify greater trochanteric pain syndrome, likely due to a hip rotator cuff tear. Her lower back pain may be aggravated by altered spinal mechanics. This situation is common, as there are multiple potential contributors to this pain, some of which are more likely to be causal than others.
There are a number of important differential diagnoses to be considered in persons with greater trochanteric pain: trochanteric bursitis is rarely an isolated entity and often coexists with hip rotator cuff degenerative changes, and it frequently presents in older females.
Hip osteoarthritis usually causes groin more than buttock pain — and rarely isolated trochanteric pain. Likewise, isolated trochanteric pain is unusual in somatic-referred spinal pain from lumbar spondylosis, which is frequently found on imaging, even in the asymptomatic adult. The character and distribution of lumbosacral radicular pain are respectively neuropathic and dermatomal. Herpes zoster presents with buttock pain prior to the development of vesicles. Other causes of trochanteric pain are uncommon. Rarely, superior gluteal nerve injury can produce this pattern of weakness.
Vicki has been repeatedly investigated with imaging and treated with interventions based on findings interpreted to be causal but frequently seen in older patients. These interventions were ineffective.
Imaging of the thigh, buttock and hip is frequently performed. For example, MBS item numbers for ultrasound of the hip in 2014/15 were processed in 262,003 instances (at a cost of $26.4 million), whereas in 2004/05, ‘only' $6 million was spent. Costs of MRIs are uncertain, but likely comparable, and do not take into account the significant patient costs when non-rebatable.
The literature reveals that trochanteric bursitis rarely exists in isolation and is typically associated with gluteal tendonopathy and/or muscle tears.
The pre-test probability of hip rotator cuff pathology is at least moderate in adult women, which could suggest that imaging findings may be false positives and that therapy based on these findings may neither be indicated nor successful.
Moreover, the literature indicates there is no established treatment pathway for the management of lateral hip pain, and one systematic review of this used clinical diagnosis rather than any form of imaging as entry criteria.
Thus, relying heavily on imaging to diagnose lateral hip pain is fallacious, particularly since there is a paucity of evidence that treatment decisions based on imaging improve outcomes. There is no clear, high-quality evidence indicating that radiological-guided injections are superior to blind injections. Surgical management of upper lateral thigh pain is occasionally undertaken, but the result of tendon repairs and bursectomies for persons with protracted pain is often disappointing.
Vicki is best treated with physical therapy to improve hip rotator cuff strength and core stabilisation, and she is encouraged to undertake weight-bearing exercise on level, not sloping, ground to achieve a caloric deficit. Repeated corticosteroid injections should be discouraged.
Associate Professor Mark Arnold is the associate dean of the University of Sydney’s School of Rural Health.
References on request.
This article was originally published in Australian Doctor on 8 March 2016. It was independently written, produced, edited and fact-checked by the Australian Doctor editorial team for our print and digital products.