Castor oil decreases pain during extracorporeal shock wave application

In a prospective single-blind study the contact media ultrasound gel, vasel ine and castor oil were examined for their effect on surface pain caused by extracorporeal shock waves used for tendinosis calcarea (n = 25), radiohum eral epicondylitis (n = 23) and plantar heel spur (n = 12). A total of 60 p atients was divided into six groups. Using a Compact S shockwave source (Do rnier MedTech), an energy flux density up to 0.12 mJ/mm(2) was applied thre e times within 3 weeks. Independent of the diagnosis, there was a statistic ally significant influence of the contact medium on the intensity of applic ation pain. In this comparison castor oil was best. For the diagnosis of te ndinosis calcarea and plantar heel spur, castor oil was significantly bette r than the other two contact media, while for epicondylitis there was no si gnificant difference. Castor oil was found to have an advantage over ultras ound jelly and vaseline in all indications used with regard to application pain. The positive effect of castor oil can be explained by its cavitation- free quality.