Comparison of Extracorporeal Shockwave Therapy and Blind Steroid Injection in Patients With Coccydynia: A Randomized Clinical Trial.

OBJECTIVE

Extracorporeal shockwave therapy (ESWT) emerged recently for the treatment of musculoskeletal conditions owing to its regenerative and anti-inflammatory effects. In this study, the aim was to compare the efficacies of ESWT and steroid injection in patients with coccydynia.

DESIGN

Thirty-four patients with coccydynia were randomized into two groups. In the ESWT group, patients received radial shockwave for three weekly sessions. The second treatment group received an injection of steroid in the tip of the coccyx or sacrococcygeal junction. Outcome measures were visual analog scale, Short-Form Health Survey, and Dallas Pain Questionnaire. Visual analog scale was measured at baseline and 1 wk, 1 mo, 2 mos, and 6 mos after the intervention. Short-Form Health Survey and Dallas Pain Questionnaire were assessed before and 1 mo after treatment.

RESULTS

The visual analog scale score was significantly decreased in all follow-ups in both groups. There was also a significant decrease between 1 wk and three other posttreatment visits in the ESWT treatment group. Time and group interaction effect was significant on the visual analog scale (F2.64, 84.63 = 2.95, P = 0.043), in favor of ESWT. Concerning the Short-Form Health Survey and Dallas Pain Questionnaire, only some dimensions improved.

CONCLUSIONS

ESWT is an effective intervention in patients with coccydynia and had more long-lasting efficacy than steroid in terms of pain relief over 6 mos of observation.