Research Review By Dr. Jeff Cubos©

Date Posted:

December 2009

Study Title:

Home Training, Local Corticosteroid Injection, or Radial Shockwave Therapy for Greater Trochanter Pain Syndrome

Authors:

Rompe JD, Segal NA, Cacchio A et al.

Author's Affiliations:

OrthoTrauma Evaluation Center, Mainz, Germany
Department of Orthopaedics & Rehabilitation, University of Iowa, Iowa City, Iowa
Dipartimento di Medicina Fisica e Riabilitazione, Ospedale “San Salvatore” di L’Aquila, L’Aquila, Italy

Publication Information:

American Journal of Sports Medicine 2009; 37(10): 1981-1990.

Background Information:

The use of “Trochanteric Bursitis” as a diagnosis for lateral hip pain is extremely common in orthopaedics and manual therapy. However, given the numerous anatomical structures in the region of the lateral hip, recent literature has moved towards labeling a collection of signs and symptoms in this region as ”Greater Trochanter Pain Syndrome”.

Greater Trochanter Pain Syndrome (GTPS) involves:
  • Chronic continuous or intermittent pain local to the greater trochanter region
  • Potential radiation to the lateral hip or thigh
  • Pain may increase with activity
  • Pain is aggravated by lying on the affected side
  • Pain is reproduced upon local palpation of the greater trochanter
  • Supine resisted hip external rotation and single-legged stance may be positive for tendinous or bursal involvement
  • Higher prevalence in women and those 40-60 years of age
  • Patients may also present with tenderness of the iliotibial band and osteoarthritis of the knee (usually due to altered biomechanics of the lower extremities).
Treatment for GTPS commonly consists of an initial course of non-steroidal anti-inflammatory medication, electrotherapeutic modalities, and rehabilitative therapy. Local injection of corticosteroids has been regarded as the standard of care, however, its beneficial effect has yet to be validated by controlled research methods. Similarly, studies examining the effect of home training and shock wave therapy specific to GTPS have also yet to be performed.

Pertinent Results:

This study set out to compare the individual effectiveness of home training, corticosteroid injection, and radial shock wave therapy on GTPS. Formal randomization of subjects into the three separate groups was not utilized in this study, however, no significant differences between the three groups were revealed. General outcome measures were assessed at baseline, 1 month, 4 months, and 15 months from baseline.

Pertinent Results Include:
  • At 1 month from baseline, significantly more subjects from the corticosteroid group reported improvement in comparison to the home training and shock wave therapy groups.
  • At 4 months from baseline, significantly more subjects from the shock wave therapy group reported improvement in comparison to the corticosteroid and home training groups.
  • Finally, at 15 months from baseline, most improvements were demonstrated in the home training group. However, both the home training and shock wave therapy groups showed significantly more improvement than the corticosteroid group. No significant difference in improvement was found between the home training and shockwave groups.
Return to previous level of sports and/or recreational activity was examined at 4 months from baseline and it was revealed that significantly more subjects in the shock wave therapy group were able to return to activity as compared to both the home training and corticosteroid groups. Return to activity at 15 months from baseline was not reported.

While co-intervention was discouraged, all subjects were permitted to consume 2000-4000 mg/d of paracetamol for pain if requested. Significant differences in consumption between the groups (if any) were not reported. Further, increased pain was the most frequently reported side effect of both home training and corticosteroid injection within the first month of treatment. In contrast, bruising was the most commonly reported side effect by the shock wave therapy group.

Clinical Application & Conclusions:

This study examined the individual effects of a standardized home training program, single corticosteroid injection, and standardized shock wave therapy protocol on greater trochanter pain syndrome in subjects from 2 orthopaedic outpatient clinics. Its results demonstrated that specific modalities provide beneficial therapeutic effects at different time points of recovery for GTPS.

As demonstrated from the findings above, one may deduce that initial symptomatic relief for GTPS may be obtained from local corticosteroid injection, whereas mid- to long-term relief may be obtained from shock wave therapy and home exercise, respectively. Combined therapeutic effect was not included in this study although its use in mainstream practice is certainly widespread.

Perhaps future research examining the combined effect of the above modalities (and perhaps including other manual therapy techniques) may lead to the development of sound protocols for the management of GTPS. Therefore, until such research is performed, evidence simply demonstrates that isolated therapies have differing effects at distinct time periods.

Study Methods:

611 patients suffering from persistent lateral hip pain, obtained from 2 orthopaedic outpatient clinics, were invited to participate in this study. Subjects were sequentially assigned their corresponding treatment groups.

Inclusion criteria:
  • Local tenderness with 1.5 to 3.0 kg of palpation pressure as measured by a Wagner Force Dial dolorimeter.
  • Greater than 6 months of pain anterior, lateral, or posterior to the greater trochanter
  • The presence of pain when lying on the affected side
  • Pain reproduction with resisted hip external rotation in the supine position (hip and knee both flexed to 90 deg.)
  • Absence of hip and knee disease upon radiologic examination.
Exclusion criteria:
  • GTPS resulting from acute trauma
  • Pain resulting from such causes as dysplasia, deformities, and sciatica
  • Less than or equal to 20 degrees of hip internal rotation (with pain)
  • General tenderness of myofascial origin upon palpation
  • Bilateral GTPS signs and symptoms
  • History of local injection within 6 months prior to study
  • History of spinal and/or hip surgery
  • Recent onset of low back pain
  • Infection of the hip or local structures
  • Blood coagulation abnormalities
  • Co-morbidities that are vascular, neurologic, or neoplastic in origin
A total of 229 subjects met all 5 inclusion criteria, although 16 could not be re-examined at the 4 month follow-up. The last observations recorded from these 16 individuals were carried forward to replace the missing responses. No specific group was revealed to significantly differ with respect to missing responses.

Home Training protocol:
  • Piriformis stretch (held for 30-60 seconds, repeated 3 times)
  • Standing Iliotibial band stretch (held for 30 seconds, repeated 3 times)
  • Straight leg raise (10 inches off floor. 3 sets of 10 repetitions)
  • Wall squat with ball or pillow squeezed between the thighs (held for 10 seconds, repeated 20 times)
  • Prone hip extensions for gluteal strengthening (8 inches off floor. Held for 5 seconds. 3 sets of 10 repetitions)
This protocol was to be performed twice daily, 7 days per week, for a period of 12 weeks.

Corticosteroid Injection group:
  • Injections were performed at the point of maximum tenderness and swelling local to the palpated greater trochanter
  • A 22- or 25-gauge needle delivered 5 mL of 0.5% Mepivacain mixed with 1 mL of Prednisolone.
Shock Wave Therapy Group:
  • Patients in this group received 3 weekly sessions of radial shock wave therapy.
  • Each session included 2000 pulses, applied at 3 bar (pressure), at a frequency of 8 pulses per second.
  • The area of maximum tenderness was treated in a circumferential pattern with no local anesthesia administered.
Regardless of treatment group, all participants were instructed to slowly return to their previous levels of sporting or recreational activity.

As mentioned above, general outcome measures were assessed at baseline, 1 month, 4 months, and 15 months. The primary outcome measures examined the degree of recovery at 4 months utilizing a 6-point Likert scale as well as the rating of pain during the past week using a 10-point numeric rating scale.

These were also examined as secondary outcome measures at 1 month and 15 months from baseline, along with medication use, hospital, physician or therapist visits, side effects, and diagnostic tests. Also examined was their ability to return to previous levels of activity.

Aiming for success rates of 40% in the least successful group and 65% in the most successful groups (25% difference between groups), target sample sizes of 75 patients per group were sought. In actuality, 71 patients from the home training group, 69 patients from the corticosteroid group, and 73 patients from the shock wave therapy group were examined.

Differences in improvement between the groups were examined and confidence intervals (CI) revealed. Analyses of variance (ANOVA) were performed and revealed significant effects of treatment and treatment-time interaction (P < 0.01) at the 1, 4, and 15 month follow ups. When significant main effects and interactions were demonstrated, a Tukey post hoc comparison was performed to assess significant differences between mean values. Lastly, differences in baseline characteristics, and success and failures were examined via the Fisher exact test. The significance level for all analyses was set at P < 0.05.

Study Strengths / Weaknesses:

Although no significant differences between the three subject groups were revealed, one major limitation of this study was the lack of formal randomization of subjects into the three separate groups. Further, it is understandable that the objective of this study was to examine the differing effects of the individual treatment protocols, however, true clinical practice often sees the incorporation of a combination of the above and/or additional therapeutic modalities.

Therefore, future studies examining combined effects of 2 or more of the above therapeutic approaches may provide practical guidelines for the management of GTPS.

As an aside, the inclusion of an adduction moment combined with a squat exercise (in the home training protocol) seems trivial given the current state of the literature pertaining to the beneficial effects of adding various abduction exercises for lateral hip related musculoskeletal conditions.