Background Although small observational studies have suggested that local corticosteroid (CS) injection may be effective in the management of the greater trochanteric pain syndrome (GTPS), no prospective placebo controlled study has been carried out to establish the efficacy of this common intervention.
Objectives To perform a randomized double-blind placebo controlled trial to investigate the efficacy of local CS injection in the management of GTPS.
Methods The trial was conducted in the Rheumatology unit of a University teaching hospital in Geneva, Switzerland. Inclusion criteria were lateral hip pain (LHP) for greater than 1 month, a LHP score of ≥4 in the preceding week, failure of another standard treatment (physiotherapy, analgesics, etc.) and typical LHP reproduced by palpation of the greater trochanter (GT). Participants were randomised in a 1:1 ratio to: 1) injection with a combination of local anaesthetic and CS (Treatment group), or 2) injection with normal saline solution (Placebo group). The Treatment group received 4ml of 1% Lidocaine (Rapidocain®) and 1ml of Bethametasone (Diprophos®). The Placebo group received 5ml of sterile saline solution. Injections were performed under ultrasound guidance. The study's predefined primary outcome of interest was the difference in pain intensity at 4 weeks post-injection between the 2 groups. Secondary outcomes included the number of “responders” (pain score improvement of ≥1.5) and the number of patients with low disease activity (LDA) (pain score ≤2.0). Patients were followed up for 6 months.
Results A total of 46 patients were included and there were no significant differences between the 2 groups at baseline (Table 1). There were no significant differences between the 2 groups in terms of the reduction in pain at one month post-injection, with scores of -1.5 and -2.5 (p=0.23) in the Treatment and Placebo groups respectively. When including all measures in the first 3 weeks and using multilevel regression, there was a marginally significant improvement in pain scores in favour of the Treatment group (p=0.08) (Figure 1). There were no significant differences in terms of the percentage of responders (p=0.32), or patients with LDA (p=0.50) between the 2 groups at follow up. There were no significant differences in pain scores between groups at 3 and 6 months post-injection.
Conclusions Local corticosteroid injection in the management of GTPS is only marginally effective for a few weeks. Given the lack of long-term improvement and the potential for cortisone-related side-effects, this intervention is of limited benefit.
Disclosure of Interest None declared