Is Adding Extracorporeal Shock Wave Therapy to Physiotherapy and Corticosteroid Injection Beneficial for Frozen Shoulder

ESWT group. Patients in the ESWT group will receive ESWT, physical therapy, and both shoulder joint (glenohumeral joint, GHJ) and SASD bursa injection for 2 times in a 2-week interval. 3ml triamcinolone (1ml triamcinolone= 10mg) will be added to 3ml 1% xylocaine to make 6ml injectate. Among them, 4ml injectate will be injected into the posterior GHJ with a 7 cm 23-gauge needle under ultrasound (US) guidance. After withdrawing the needle to subcutaneous layer, another 2ml injectate will be injected into the SASD bursa of the affected shoulder under US guidance.

SHAM group. The participants will receive the same dosage and technique of corticosteroid posterior GHJ and SASD bursa injection for 2 times at 2 weekly interval as participants do in the ESWT group. For creating a single-blinded condition, they will also receive 4 ESWT treatments at weekly interval except that the energy flux density is set at 0.04 mJ/mm2. For sham ESWT, the machine still makes a noise with every shock wave delivered in order to enhance the sham design.