Disappointing results seen in randomized study of ESWT therapy for jumper’s knee

Issue: Issue 5 2010

OSLO — Dutch investigators who conducted a multicenter randomized trial of shock wave therapy found it ineffective for treating jumper’s knee vs. placebo shock wave therapy in athletes who continued to play sports or train during their treatment.

“There was no effect of this shock wave treatment protocol on pain, function and sport participation in athletes with patellar tendinopathy with mild symptoms for less than 12 months who kept playing sports,” Johannes Zwerver, MD, of the University Medical Center Groningen Sports Medicine Department, in Groningen, The Netherlands, said at the 2010 ESSKA Congress.

Sixty-two jumping athletes who had patellar tendinopathy symptoms for less than 12 months were randomized in-season to the ESWT or sham ESWT groups. The ESWT group underwent one ESWT treatment without anesthesia per week for 3 weeks. The sham group followed the same protocol; however, the ESWT device was disabled during their treatments.

Patients and assessors were blinded to who received the active or placebo treatments. Both groups were demographically similar, Zwerver noted.

At 1, 12 and 22 weeks following final treatment, patients were assessed using the Dutch version of the Victorian Institute of Sport Assessment-Patella (VISA-P) score, an index of the severity of jumper’s knee symptoms, function and ability to perform physical activity; 100 points represents the ability to perform activities without symptoms.

At baseline, both groups’ mean VISA-P scores were 60 points, indicating that they had mild symptoms. After 1 week, both groups’ mean scores reached approximately 66.5 points. By 12 weeks the scores were about 70 points in the placebo group and 67 points in the ESWT group; at 22 weeks they were 74 points in the placebo group and 71 points in the ESWT group.

“There was a significant effect over time, but no significant difference found between the shock wave and placebo group,” Zwerver said. “Statistically, more athletes from the shock wave group reported a subjective improvement 1 week after treatment,” he said.

“There is an urgent need for more basic and clinical research into this topic,” Zwerver noted. – by Susan M. Rapp

References:

Zwerver J, van den Akker-Scheek I, Hartgens F, et al. The TOPGAME-study: effectiveness of extracorporeal shockwave therapy in jumping athletes with patellar tendinopathy; a randomized controlled trial. Paper FP20-652. Presented at the 2010 ESSKA Congress. June 9-12, 2010. Oslo.

Zwerver J. BMC Musculoskelet Disord. 2010;11:28.

Johannes Zwerver, MD, can be reached at Hanzeplein 1, 9700 RB Groningen, The Netherlands; +31-50-3616161; e-mail: j.zwerver@sport.umcg.nl. The study was funded by the Dutch Ministry of Health and the Dutch Basketball, Handball and Volleyball Association.

The results of this study are not surprising. The well codified indications for ESWT are failure of conservative management and chronic tendinopathy. Also, it has been shown that other forms of physical therapy do not work in athletes who continue to play sport during the treatment period. In the present study, instead, the authors tested the effectiveness of ESWT as primary therapy in athletes who keep playing sports despite having patellar tendon pain.

The study, therefore, shows that appropriate enrollment criteria should be used, and that athletes, coaches, agents, trainers and other professionals involved in their care should swallow the pill that the athletes need to modify their activity profile.

– Nicola Maffulli, MD, MS, PhD, FRCS(Orth)
Centre Lead and Professor of Sports and Exercise Medicine, Consultant Trauma and Orthopaedic Surgeon
Queen Mary University of London Barts and
The London School of Medicine and Dentistry Institute of Health Sciences Education

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