Greater trochanteric pain syndrome (GTPS) is estimated to affect between 10% and 25% of the population in industrialized societies.1–3 Considering the prevalence, frequent misconceptions that surround the condition and elemental limitations in diagnosis and treatment, the relative paucity of studies and reviews published on this topic is somewhat surprising. To address this knowledge gap, we have undertaken a comprehensive, evidence-based review of the literature with the purpose of critically evaluating the epidemiology, etiology, diagnosis, and treatment of GTPS. Articles reviewed were obtained via MEDLINE and OVID search engines, book chapters, and bibliographic references dating to the early 1900s.
Trochanteric bursitis (TB) is a term used to describe chronic, intermittent pain accompanied by tenderness to palpation overlying the lateral aspect of the hip.4,5 First described by Stegemann in 1923, TB has been referred to as the “Great Mimicker” because it is frequently mistaken for other conditions.6,7 Yet, the term “trochanteric bursitis” may in fact be a misnomer given that three of the cardinal symptoms of inflammation, erythema, edema and rubor, are uncommon.5,8 More than 50 years ago, Leonard9 proposed using the phrase “trochanteric syndrome” to refer to symptoms in the vicinity of the trochanter major. The term “greater trochanteric pain syndrome” may better characterize the condition because pain and reproducible tenderness in the region of the greater trochanter (GT), 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.10 GTPS, which to some extent has already replaced TB 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.11 Four bursae have been consistently described outside the GT, with three being present in most individuals. These bursae serve to provide cushioning for the gluteus tendons, ITB, and tensor fascia latae.5Figure 1 illustrates the relationship of the various bursae to the bony landmarks.
The gluteus minimus bursa is a minor bursa located cephalad and ventral to the GT. The two major bursae are the subgluteus maximus and subgluteus medius bursae. The subgluteus maximus bursa is located lateral to the GT, juxtaposed between the gluteus medius tendon and the gluteus maximus muscle. This largest of the greater trochanteric bursae is most frequently incriminated in GTPS. In an anatomical study by Dunn et al.,12 the authors found at least one subgluteus maximus bursa present in 13 of 16 dissected cadaver hips. In each of the 13 specimens containing a subgluteus maximus bursa, the largest bursa was found to lie just superficial to the common attachment of the gluteus medius, minimus and vastus lateralis muscles onto the lateral surface of the GT. This was referred to as the “deep” subgluteus maximus bursa or “deep dominant” bursa if there were more than two in the same tissue plane. In five specimens, at least one secondary subgluteus maximus bursa was present. This smaller, “superficial” subgluteus maximus bursa tended to be present deep within the surface of the gluteus maximus muscle, near to where the fibers inserted into the fascia lata. In 2 of the 16 hip specimens, deep and 2 superficial subgluteus maximus bursae were identified.
Woodley et al.13 investigated the bursae deep to the tendons of each of the gluteal muscles (gluteus maximus, gluteus medius, and gluteus minimus) in 18 embalmed human hips (Table 1). Four different bursae were located deep to the gluteus maximus (deep, secondary deep, superficial subgluteus maximus, and gluteofemoral bursae). The deep subgluteus maximus bursa, often referred to as the “trochanteric bursa,” was positioned deep to the fascia lata and the gluteus maximus muscle; it was present in 16 of the 18 specimens. The secondary deep subgluteus maximus bursa was present in the same plane as the dominant deep subgluteus maximus bursa, posterior to the dominant deep bursa, in 6 of 18 specimens. In 8 of the 16 specimens the superficial subgluteus maximus bursa was positioned superficial to the deep bursa and was attached to overlying tissues during dissection. The gluteofemoral bursa was present in 17 of 18 hips but was associated with the GT in only 10 of 18 specimens.
In these cases, the gluteofemoral bursa was positioned caudal to the GT and deep and superficial subgluteus bursae, and adhered to the ITB in the area where the tendinous fibers of the gluteus maximus inserted. Deep to the gluteus medius tendon, on the anterior surface of the GT, three bursae were located. The two major bursae were the anterior subgluteus medius bursa, found in 16 of 18 specimens, and the piriformis bursa, identified in 15 of 18 hips. A secondary piriformis bursa was found in 4 of 18 hips. The anterior subgluteus medius bursa was generally located deep to the gluteus medius tendon, and anterior to the piriformis bursa and apex of the GT. The piriformis bursa (a.k.a. posterior subgluteus medius bursa) tended to be found at the insertion of the piriformis muscle at the apex of the GT. Two bursae were identified deep to the gluteus minimus tendon: the primary and secondary subgluteus minimus bursae. The primary subgluteus minimus bursa was present in 15 of 18 hips, located deep to the anterior border of the gluteus minimus tendon as it inserted onto the anterior aspect of the GT, near its apex. The secondary subgluteus minimus bursa, found in 7 of 18 specimens, was usually found deep to the tendinous insertion of the gluteus minimus onto the anterolateral aspect of the GT. In summary, whereas three bursae are consistently described in the region of the GT, many secondary bursae may be present. The large and inconsistent number of bursae, combined with their variable location and unpredictable referral patterns from other potential pain generators in the area, such as the buttock, groin, and low back, may contribute to the frequent misdiagnosis of GTPS and the variable response to injection therapy.
In the United States, 10%–20% of the adults aged 60 yr or older reported hip pain on a majority of days over the previous 6 wk,14 and 2.5% of all sports-related injuries involve the hip.15 In primary care settings, the incidence of greater trochanteric pain is reported to be around 1.8 patients per 1000 per year.2 Hip pain occurs in all age groups, but is more prevalent between the fourth and sixth decades of life.5 Although most studies suggest a female predominance (3–4:1),1,10,16–18 others have not found a gender predilection.19 The presence of low back pain (LBP) seems to predispose patients to hip pain. The prevalence of GTPS in adults with musculoskeletal LBP has been reported to range between 20% and 35%.1,10,20 In a large, multicenter, cross-sectional study involving 3026 middle-age to elderly adults, Segal et al.1 found the prevalence of GTPS to be 17.6%, being higher in women and patients with coexisting LBP, osteoarthritis (OA), ITB tenderness, and obesity. Further confounding prevalence estimates is the observation that many conditions that predispose patients to GTPS can also simulate the condition (Table 2). In a retrospective analysis of 247 patients referred to an orthopedic spine center for LBP, Tortolani et al.10 found that 62.7% of patients with GTPS had previously been evaluated by a spine surgeon for suspected radicular symptoms. In a prospective, observational study involving 100 consecutive patients with rheumatoid arthritis, Raman and Haslock21 found that 15% of patients had concomitant GTPS. The higher reported incidence in women, and patients with leg length discrepancies, LBP and knee pain, suggest that altered lower-limb biomechanics and abnormal force vectors across the hip may predispose patients to GTPS.1
MECHANISM OF INJURY
Many risk factors have been associated with GTPS, including age, female gender, ipsilateral ITB pain, knee OA, obesity, and LBP.1,22 In an observational study, Schapira et al.23 found that 91.6% of patients diagnosed with TB had other associated pathological conditions, such as peripheral OA, rheumatoid arthritis, and lumbosacral OA. The increased prevalence in women may be attributed to altered biomechanics associated with differences in the size, shape, and orientation of the pelvis (gynecoid vs android), and its relationship with the ITB. Obesity may be a contributing risk factor by the combined effect of increased stress on the hip joint, hip and knee OA and LBP.1
Because TB can result from friction between the bursae and GT, it frequently occurs with overuse or trauma, especially falls.5,24 However, misdiagnosis is common. In a retrospective review of magnetic resonance imaging (MRI) obtained in 24 patients with lateral hip pain and tenderness, whereas nearly all patients had gluteus medius abnormalities, radiological evidence of bursitis was relatively uncommon, occurring in only 8% of cases.25 True bursal inflammation (bursitis) may result from either chronic microtrauma, regional muscle dysfunction, overuse or acute injury.5,24,26 The gluteus medius and minimus muscles are the major abductors of the hip and have been implicated in GTPS. The main tendon of the gluteus medius muscle attaches to the postero-superior aspect of the GT, with the lateral tendon inserting into the lateral aspect. The gluteus minimus muscle attaches to the anterior facet of the GT.27 Consequently, inflammation and tears of either the gluteus medius or minimus muscles, or their tendinous insertions, from tension imposed by the ITB and/or frictional trauma from overuse, may result in GTPS. 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.1,22 Specific etiologies of GTPS include repetitive activity, acute trauma, crystal deposition and infection, especially tuberculosis.1,28,29 When an inciting event can be identified, the initial pathology usually occurs at tendinous attachments to the GT, with secondary involvement of adjacent bursae.19 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 is not misdiagnosed as TB.24,30 Whereas bursal inflammation is often considered by lay practitioners to be the sole pathology in cases of GTPS, one small case-control study conducted in five patients who underwent total hip arthroplasty found no pathological differences in bursal specimens between three control patients without clinical TB, and two who met criteria for the disorder.18
GTPS 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.19 Invariably, there is tenderness along the lateral or posterior aspect of the GT.5,18 Pain extending to the groin or down the lateral thigh that mimics lumbar disk herniation (i.e., pseudoradiculopathy) may be reported by some individuals.10,22 Pain radiation patterns may complicate the diagnosis of GTPS because of anatomical overlap with the iliotibial tract and mid-lumbar dermatomes (L2–4)10 (Fig. 2). Not only nerve roots, but radiation patterns from other structures in the lumbar spine, including the zygapophysial joints, sacroiliac joint, and intervertebral discs and ligaments, can replicate TB.31–33 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 gluteal nerve, 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.12 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 of a patient with GTPS characteristically reveals point tenderness (“jump sign”) in the posterolateral area of the GT.10 Typically, this will be at either the site of the gluteus medius tendon insertion5,16,19 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 GT.19,34Table 3 describes the initial criteria established by Ege Rasmussen and Fano35 for a diagnosis of TB. The initial criteria for TB did not account for the many bursae at the GT nor the tendonitis that may represent the pain generator at the lateral hip. 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 disease is frequently characterized by pain elicited with flexion and extension of the hip.36 Causes of lateral hip pain, such as ITB syndrome and meralgia paresthetica, are common regional pain syndromes that can be differentiated from GTPS by physical examination signs, such as a positive Ober’s test and sensory deficits, respectively (Table 4 and Appendix). Aside from point tenderness at the lateral hip, there are a paucity of signs with high specificity for GTPS.25 Bird et al.25 conducted a prospective study in 24 patients with a clinical diagnosis of GTPS assessing the correlation between MRI and physical examination findings. Physical examination signs evaluated for their association with MRI results included Trendelenburg’s sign and pain provoked by resisted hip abduction and internal rotation. Overall, 15 patients were found to have gluteus medius tendonitis, 11 patients had a gluteus medius tear, two patients had trochanteric bursal distension, and one had avascular necrosis of the femoral head. Trendelenburg’s test was noted to be the most accurate test in detecting a tendon tear, with a sensitivity of 73% and a specificity of 77%. It was also found to have the highest reliability of the three physical signs.25 Yet, despite its long-standing history and high prevalence rate, few studies have evaluated the association between physical examination findings and trochanteric bursa pathology (Table 5).
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.29 When these interventions 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%.17,19,35–38 Although there are no placebo-controlled trials evaluating the efficacy of corticosteroid injection therapy, several prospective studies have been published36 (Table 6). In an open observational study, Shbeeb et al.36 found landmark-guided corticosteroid injections to be effective in 77% of patients 1 wk after injection, and 61% of patients 6-mo postprocedure. 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.37,39 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.40 In patients who fail conservative treatment, surgical intervention has been advocated. This recalcitrant TB can sometimes be addressed with arthroscopic bursectomy and/or ITB release.6 In a prospective study, Baker et al.41 investigated the effectiveness of arthroscopic trochanteric bursectomy for recalcitrant TB in 30 patients. The mean pain score improved from a visual analog scale score of 7.2 preoperatively to 3.1 at final follow-up (mean, 26.1 mo). In another prospective study, Craig et al.42 evaluated ITB lengthening for refractory TB in 15 patients (17 hips) with a mean follow-up of 47 mo. Complete resolution of symptoms was reported in 8 of 17 patients, partial relief occurred in 8 patients, and 1 patient experienced no benefit.
Similar to other interventional procedures,43–45 fluoroscopy has been advocated for trochanteric bursa injections to confirm appropriate needle placement.37 Cohen et al.37 sought to determine the accuracy of landmark-guided trochanteric bursa injections by using fluoroscopy to discern injectate spread. Among the 40 patients enrolled in the study, a bursagram was obtained during the initial injection in only 45% of cases. Not surprisingly, a trend was noted whereby accuracy was found to be positively correlated with experience level. In a follow-up multicenter randomized study, Cohen et al. (BMJ, accepted for publication) allocated 65 patients with clinical TB to receive either landmark (i.e., blinded) or fluoroscopically guided corticosteroid and local anesthetic bursa injections. No significant differences were noted in 3-mo outcomes between the blinded and fluoroscopically guided groups, nor were differences appreciated between intra- and extra-bursal injections. Conceivably, targeting the bursa with fluoroscopy may actually be counterproductive in those patients without true bursal inflammation. Extra-bursal injections may be more likely to occur in patients with diffuse tenderness, distorted anatomy, and high Body Mass Indexes.37
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 GTPS supplanting “TB.” 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 GTPS.
GTPS typically presents as chronic pain in the lateral hip pain and/or buttock that is exacerbated by various positions and maneuvers. Many patients experience pain radiating along the lateral aspect of the thigh to the knee, which is often confused with lumbar spinal pathology. The diagnosis of GTPS is based on history and physical examination findings, which include point tenderness at the lateral hip and a positive response to provocative testing.
Examination tools such as Ober’s test, Thomas test, and straight leg raising may assist in determining the etiology of the posterolateral hip pain.
The treatment of GTPS initially involves conservative therapy, such as physical therapy, weight loss, nonsteroidal antiinflammatory drugs, and behavior modification. When pain persists, TB injections done with local anesthetic and corticosteroid can provide intermediate-term relief. Severe cases of refractory GTPS can also be treated with surgical intervention.
1. Segal NA, Felson DT, Torner JC, Zhu Y, Curtis JR, Niu J, Nevitt MC. Greater trochanteric pain syndrome: epidemiology and associated factors. Arch Phys Med Rehabil 2007;88:988–92
2. Lievense A, Bierma-Zeinstra S, Schouten B, Bohnen A, Verhaar J, Koes B. Prognosis of trochanteric pain in primary care. Br J Gen Pract 2005;55:199–204
3. Collee G, Dijkmans BA, Vandenbroucke JP, Cats A. Greater trochanteric pain syndrome (trochanteric bursitis) in low back pain. Scand J Rheumatol 1991;20:262–6
4. Alvarez-Nemegyei J, Canoso JJ. Evidence-based soft tissue rheumatology: III: trochanteric bursitis. J Clin Rheumatol 2004;10:123–4
5. Shbeeb MI, Matteson EL. Trochanteric bursitis (greater trochanter pain syndrome). Mayo Clin Proc 1996;71:565–9
6. Farr D, Selesnick H, Janecki C, Cordas D. Arthroscopic bursectomy with concomitant iliotibial band release for the treatment of recalcitrant trochanteric bursitis. Arthroscopy 2007;23:905 e1–e5
7. Stegemann H. Die chirurgische bedevtung paraartikularer kalkablagerungen. Arch Klin Chir 1923;125:718–38
8. Paluska SA. An overview of hip injuries in running. Sports Med 2005;35:991–1014
9. Leonard MH. Trochanteric syndrome; calcareous and noncalcareous tendonitis and bursitis about the trochanter major. J Am Med Assoc 1958;168:175–7
10. Tortolani PJ, Carbone JJ, Quartararo LG. Greater trochanteric pain syndrome in patients referred to orthopedic spine specialists. Spine J 2002;2:251–4
11. Margo K, Drezner J, Motzkin D. Evaluation and management of hip pain: an algorithmic approach. J Fam Pract 2003;52:607–17
12. Dunn T, Heller CA, McCarthy SW, Dos Remedios C. Anatomical study of the “trochanteric bursa.” Clin Anat 2003;16:233–40
13. Woodley SJ, Mercer SR, Nicholson HD. Morphology of the bursae associated with the greater trochanter of the femur. J Bone Joint Surg Am 2008;90:284–94
14. Christmas C, Crespo CJ, Franckowiak SC, Bathon JM, Bartlett SJ, Andersen RE. How common is hip pain among older adults? Results from the Third National Health and Nutrition Examination Survey. J Fam Pract 2002;51:345–8
15. Anderson K, Strickland SM, Warren R. Hip and groin injuries in athletes. Am J Sports Med 2001;29:521–33
16. Anderson TP. Trochanteric bursitis: diagnostic criteria and clinical significance. Arch Phys Med Rehabil 1958;39:617–22
17. Krout RM, Anderson TP. Trochanteric bursitis: management. Arch Phys Med Rehabil 1959;40:8–14
18. Silva F, Adams T, Feinstein J, Arroyo RA. Trochanteric bursitis: refuting the myth of inflammation. J Clin Rheumatol 2008;14:82–6
19. Gordon EJ. Trochanteric bursitis and tendinitis. Clin Orthop 1961;20:193–202
20. Collee G, Dijkmans BA, Vandenbroucke JP, Rozing PM, Cats A. A clinical epidemiological study in low back pain. Description of two clinical syndromes. Br J Rheumatol 1990;29:354–7
21. Raman D, Haslock I. Trochanteric bursitis–a frequent cause of ‘hip’ pain in rheumatoid arthritis. Ann Rheum Dis 1982;41:602–3
22. Little H. Trochanteric bursitis: a common cause of pelvic girdle pain. Can Med Assoc J 1979;120:456–8
23. Schapira D, Nahir M, Scharf Y. Trochanteric bursitis: a common clinical problem. Arch Phys Med Rehabil 1986;67:815–17
24. Jones DL, Erhard RE. Diagnosis of trochanteric bursitis versus femoral neck stress fracture. Phys Ther 1997;77:58–67
25. Bird PA, Oakley SP, Shnier R, Kirkham BW. Prospective evaluation of magnetic resonance imaging and physical examination findings in patients with greater trochanteric pain syndrome. Arthritis Rheum 2001;44:2138–45
26. Johnston CA, Wiley JP, Lindsay DM, Wiseman DA. Iliopsoas bursitis and tendinitis. A review. Sports Med 1998;25:271–83
27. Pfirrmann CW, Chung CB, Theumann NH, Trudell DJ, Resnick D. Greater trochanter of the hip: attachment of the abductor mechanism and a complex of three bursae–MR imaging and MR bursography in cadavers and MR imaging in asymptomatic volunteers. Radiology 2001;221:469–77
28. Abdelwahab IF, Bianchi S, Martinoli C, Klein M, Hermann G. Atypical extraspinal musculoskeletal tuberculosis in immunocompetent patients: part II, tuberculous myositis, tuberculous bursitis, and tuberculous tenosynovites. Can Assoc Radiol J 2006;57:278–86
29. Butcher JD, Salzman KL, Lillegard WA. Lower extremity bursitis. Am Fam Physician 1996;53:2317–24
30. Mandell BF. Avascular necrosis of the femoral head presenting as trochanteric bursitis. Ann Rheum Dis 1990;49:730–2
31. Cohen SP, Raja SN. Pathogenesis, diagnosis, and treatment of lumbar zygapophysial (facet) joint pain. Anesthesiology 2007;106:591–614
32. Cohen SP. Sacroiliac joint pain: a comprehensive review of anatomy, diagnosis, and treatment. Anesth Analg 2005;101:1440–53
33. Ohnmeiss DD, Vanharanta H, Ekholm J. Relation between pain location and disc pathology: a study of pain drawings and CT/discography. Clin J Pain 1999;15:210–17
34. Beck M, Sledge JB, Gautier E, Dora CF, Ganz R. The anatomy and function of the gluteus minimus muscle. J Bone Joint Surg Br 2000;82:358–63
35. Ege Rasmussen KJ, Fano N. Trochanteric bursitis. Treatment by corticosteroid injection. Scand J Rheumatol 1985;14:417–20
36. Shbeeb MI, O’Duffy JD, Michet CJ Jr, O’Fallon WM, Matteson EL. Evaluation of glucocorticosteroid injection for the treatment of trochanteric bursitis. J Rheumatol 1996;23:2104–6
37. Cohen SP, Narvaez JC, Lebovits AH, Stojanovic MP. Corticosteroid injections for trochanteric bursitis: is fluoroscopy necessary? A pilot study. Br J Anaesth 2005;94:100–6
38. Swezey RL. Pseudo-radiculopathy in subacute trochanteric bursitis of the subgluteus maximus bursa. Arch Phys Med Rehabil 1976;57:387–90
39. Walker P, Kannangara S, Bruce WJ, Michael D, Van der Wall H. Lateral hip pain: does imaging predict response to localized injection? Clin Orthop Relat Res 2007;457:144–9
40. Sayegh F, Potoupnis M, Kapetanos G. Greater trochanter bursitis pain syndrome in females with chronic low back pain and sciatica. Acta Orthop Belg 2004;70:423–8
41. Baker CL Jr, Massie RV, Hurt WG, Savory CG. Arthroscopic bursectomy for recalcitrant trochanteric bursitis. Arthroscopy 2007;23:827–32
42. Craig RA, Jones DP, Oakley AP, Dunbar JD. Iliotibial band Z-lengthening for refractory trochanteric bursitis (greater trochanteric pain syndrome). ANZ J Surg 2007;77:996–8
43. Fishman SM, Caneris OA, Bandman TB, Audette JF, Borsook D. Injection of the piriformis muscle by fluoroscopic and electromyographic guidance. Reg Anesth Pain Med 1998;23:554–9
44. Fredman B, Nun MB, Zohar E, Iraqi G, Shapiro M, Gepstein R, Jedeikin R. Epidural steroids for treating “failed back surgery syndrome”: is fluoroscopy really necessary? Anesth Analg 1999;88:367–72
45. Stojanovic MP, Vu TN, Caneris O, Slezak J, Cohen SP, Sang CN. The role of fluoroscopy in cervical epidural steroid injections: an analysis of contrast dispersal patterns. Spine 2002;27:509–14
46. Frontera WR, Silver JK. Essentials of Physical Medicine and Rehabilitation. St. Louis, MO: Mosby, 2002
47. DeLee J, Drez D, Miller MD. DeLee and Drez’s Orthopaedic Sports Medicine Principles and Practice. Philadelphia, PA: Saunders, 2003:2 v. (xxviii, 2623, lx p.)
48. Benzon H, Srinivasa R, Molloy R, Liu S, Fishman S. Essentials of Pain Med and Regional Anesthesia. 2nd ed. Philadelphia, PA: Elsevier Churchill-Livingstone, 2005:358–9
49. Lequesne M, Mathieu P, Vuillemin-Bodaghi V, Bard H, Djian P. Gluteal tendinopathy in refractory greater trochanter pain syndrome: diagnostic value of two clinical tests. Arthritis Rheum 2008;59:241–6
50. Karpinski MR, Piggott H. Greater trochanteric pain syndrome. A report of 15 cases. J Bone Joint Surg Br 1985;67:762–3