Corticosteroid Injections for Greater Trochanteric Pain Syndrome: A Randomized Controlled Trial in Primary Care

Brinks et al. conducted an RCT comparing a steroid injection to usual care for “Greater Trochanteric Pain Syndrome,” or GTPS, and found that pain was significantly improved at 3 months for patients randomized to the steroid injection protocol. We felt that the authors might have provided a bit more information about the epidemiology and diagnosis of GTPS, and about current treatment approaches. We have one or two suggestions to potentially improve the design of a follow-up RCT to this excellent study.

While the incidence of GTPS is about 1.8 per 1000 primary care patients per year, the prevalence may be as high as 17.6% of middle-aged to elderly adults, with increased risk among women, the obese and among persons with lower back pain, knee osteoarthritis, flat feet, leg length discrepancy or abnormal gaits. Primary care clinicians would benefit from knowing more about GTPS, yet we are not convinced that a steroid injection should be the first-line treatment approach.

Diagnosing GTPS is not always straightforward: 62.7% of patients with GTPS in one study had previously been evaluated in a spine clinic for radicular symptoms (Tortolani 2002, Lievense 2005). Specifically, GTPS needs to be differentiated from other sources of hip pain such osteoarthritis, low back pain, gluteal medius tendon strain, and piriformis syndrome. For GTPS, the patient locates the pain laterally over the greater trochanter, buttock or lateral thigh. Typically, there is no groin pain (consistent with hip osteoarthritis), no reproducible pain with internal rotation of hip (again indicative of osteoarthritis), and there are no physical signs of piriformis syndrome.

Although one review article describes the condition as typically self -limiting with analgesic treatment, physical therapy, and stretching exercises (Williams et al. 2008), there is limited research supporting a conservative treatment approach. Yet trochanteric bursitis is now referred to as a syndrome (GTPS) (Alvarez 2004, Woodley 2008) in part because it can arise from a variety of inflamed bursae and tendons in the trochanter/ buttock area. All these pain sources potentially benefit from the conservative approach described above.

While the intervention outperformed usual care at 3 months, usual care appeared to focus on analgesic treatment, with only 14 and 6 patients in usual care and the intervention, respectively, receiving physical therapy over the first 3 months of the trial. Arguably, it would be important to know whether the steroid injection intervention outperformed an optimal control or 'best standard of care in the community,' including referral to physical therapy, to inform the evidence base for how to manage GTPS.

The authors concluded that “….we found a significant and clinically relevant effect of injection with corticosteroids at 3 months in all primary outcome measurements.” First, by defining 3 outcomes measured at 2 time-points as primary (6 measurements), the authors increase the probability that at least one will be significant at the P<0.05 level by chance alone. Second, it is important to note that none of the outcomes were significantly different at 1 year. As recommended in the CONSORT statement, “Having several primary outcomes...incurs the problems of interpretation associated with multiplicity of analyses and is not recommended”. We acknowledge that no gold standard measurement for pain exists, yet the 3 pain measurements are in all likelihood highly correlated. One primary outcome measure with the best performance characteristics (reliability, validity, sensitivity to change etc.) would be preferred in any follow-up RCT.

The authors report that 5 patients randomized to injection did not receive it due to complete resolution of the GTPS symptoms prior to scheduled injection. While we do not know how many randomized to control may have experienced similar rapid pain resolution, one might assume that the 5 not receiving the treatment on the intervention side are likely to have been counted as recovered at 3 months. Thus, the effectiveness of the steroid may be over-estimated in the ITT analysis.

Certainly, further study of a steroid injection for GTPS compared to a more enhanced usual care comparator is warranted.

1. Tortolani PJ, Carbone JJ, Quartararo LG. Greater trochanteric pain syndrome in patients referred to orthopedic spine specialists. The Spine Journal 2002:4(2):251-254.

2. Lievense A, Bierma-Zeinstra S. Prognosis of trochanteric pain in primary care. Br J Gen Pract 2005;55:199–204.

3. Williams BS, Cohen SP. Greater trochanteric pain syndrome: A review of anatomy, diagnosis and treatment. Anesthesia and Analgesia 2009:108(5):1662-1670.

4. Alvarez-Nemegyei J. Evidence-based soft tissue rheumatology III: Trochanteric bursitis. J Clin Rheumatol 2004;10: 123–124)

5. Woodley S. Morphology of the bursae associated with the greater trochanter of the femur. J Bone Joint Surg Am 2008;90:284-294.

Competing interests:   None declared

In the first study of its kind, Brinks et al show the short-term benefit of a single corticosteroid injection for greater trochanteric pain syndrome (GTPS) in a primary care setting. To their credit, they observed for injection side effects as well as followed the patients for 12 months. They did not find symptomatic side effects of the steroid nor significant problems with the injection itself but the benefits did not persist at 12 months. Similar short-term, but not long-term, benefit has been seen with shoulder and elbow steroid injections.1,2

This study shows these injections appear to be safe and should be thought of as short-term relief. However, we should still have some caution. It has been observed for many years that epidural and intra- artcular steroid injections can suppress the hypothalamic-pituitary- adrenal (HPA) axis, although usually for only a few weeks. 3-5 The authors of this current study cite literature that put the inflammatory rationale for using steroids in doubt. Even though this study showed no symptomatic side effects, the biological side effects of steroid injections is still an issue. Therefore, clinicians need to weigh the suppression of the HPA axis to the benefits of short-term pain relief. Duclos et al give alert to this effect of steroids, specifically potential adrenal suppression, in athletic traumatic injuries.5

However, Brinks et al do acknowledge that the lidocaine, the needle, or placebo, could also be the reason for benefit. Simon and Travell refer to the trigger point of the tensor fascia latae as “pseudotrochanteric bursitis” and these patients can be misdiagnosed with trochanteric bursitis.6 They recommend a lidocaine injection, done in a similar manner as described in this current study, to treat this condition. The purpose is to treat the myofascial dysfunction, not inflammation, with decrease pain due to improved muscular function. So, if a clinician is concerned about the HPA axis suppression but wants short-term relief, a trial of lidocaine appears to be safe. If this does not help, this study by Brinks et al also suggests that adding steroids can be helpful. Nonetheless, long-term success needs also be our goal. Determining the role of injection with physical therapy for GTPS would be a good follow-up study.

1. Bisset L, Beller E, Jull G, Brooks P, Darnell R, Vicenzino B. Mobilisation with movement and exercise, corticosteroid injection, or wait and see for tennis elbow: randomised trial. BMJ 2006;333:939.

2. Buchbinder R, Green S, Youd JM. Corticosteroid injections for shoulder pain. Cochrane Database of Systematic Reviews 2003, Issue 1, Art NO CD004016. DOI 10.1002/14651858.CD004016

3. Benzon, H Eipdural steroid injections for low back pain and lumbosacral radiculopathy. PAIN 24(3);March 1986: 277-295.

4. Mader, R Lavi I, Luboshitzky. Evaluation of pituitary-adrenal axis function following single intraarticular injection of methylprednisolone. Arthritis and Rheumatism. 52(3); March 2005:924-928.

5. Duclos, M, Guinot M, Colsy, M, Merle, F., Baudot, C. Corcuff, JB, Lebouc, Y. High Risk of Adrenal Insufficiency after a Single Articular Steroid Injections in Athletes. Med. Sci in Sports&Exercise. 39(7). July 2007:1036-1043.

6. Travell J and Simon, D. Myofascial Pain and Dysfunction: The Trigger Point Manual. Vol 2 The Lower Extremity. Lippencot, Williams, and Wilkens. Philedelphia, PA. Pg 218.

Competing interests:   None declared