Background: Extracorporeal shock-wave therapy is recommended for calcifying tendinitis, and navigated low-energy therapy has given better results than biofeedback localization. This investigation was planned to analyze whether the outcome of navigated low-energy shock-wave therapy can be improved by raising energy flux density to middle-energy levels. The clinical and radiological differences in outcome between three sessions of low-energy navigated shock-wave therapy and two sessions of middle-energy therapy were therefore compared.
Patients, materials and methods: A prospective, randomized, observer-blind study was carried out in 50 patients whose mean age was 51 years. The population was randomized into two groups. Pain refractory to therapy was evident for more than six months in all patients. Radiographs and clinical examinations, including the Constant and Murley score, and the visual analog scale for pain assessment were performed before therapy and then after 12 weeks. Both groups of patients received navigated and X-ray-assisted, focused shock-wave treatment at weekly intervals. Group I underwent three sessions of constant low-energy treatment (0.08 mJ/mm(2); 1000 impulses) without local anesthesia; Group II received two middle-energy treatments (0.2 mJ/mm(2); 2000 impulses) with subacromial anesthesia.
Results: Forty-four patients (21 in Group I, 23 in Group II) completed the study protocol. Clinically, both groups improved significantly (P<0.0001) in the Constant and Murley score and the visual analog scale. The statistics within the groups were not significantly different. Overall, nine calcium deposits disappeared and 12 changed massively in shape and radiological density.
Conclusions: Navigated shock-wave therapy significantly improves pain and shoulder function. Patients obtained nearly equal results after three low-energy or two middle-energy sessions of shock-wave treatment. We therefore recommend two sessions of middle-energy shock-wave therapy, as performed in Group II, because of the time-saving factor.