Clinical Question: Is extracorporeal shock wave therapy effective in treating lateral epicondylitis?

Setting: Outpatient (any)

Study Design: Randomized controlled trial (double-blinded)

Allocation: Concealed

Synopsis: The authors randomly assigned 60 patients with previously untreated lateral epicondylitis to receive extracorporeal shock wave therapy or sham therapy. The patients also were instructed in forearm extensor stretching exercises. The primary outcome of this eight-week study was “treatment success,” as defined by at least a 50 percent reduction in elbow pain, a pain score no higher than 4 on a scale of 10, and no analgesic use in the past two weeks of the study. The person evaluating these outcomes was not told which treatment the patients received and the outcome was assessed via intention to treat.

Treatment was successful in 12 of the 31 patients (39 percent) who received extracorporeal shock wave therapy, compared with nine of the 29 patients (23 percent) who received sham therapy. The difference in success was not significant. The study was powerful enough to detect a modest difference in effect if one were present.

Bottom Line: Extracorporeal shock wave therapy is no more effective than sham therapy in patients with lateral epicondylitis. Other studies also have found this therapy to be ineffective for lateral epicondylitis. The few studies that show a difference usually are small and are funded by the companies that make the machines. (Level of Evidence: 1b)