Even today the aetiology of the frozen shoulder is still under discussion. At the Orthopaedic Department of the Medizinische Hochschule Hannover, 118 persons with a frozen shoulder were treated as in- or outpatients between 1980 and 1988. We investigated the results of two different specific therapy concepts. Most of the patients received a mixture of drug therapy and physical rehabilitation under the guidance of a physiotherapist. In a smaller group of patients, the frozen shoulder was mobilized under anaesthesia (mobilisation force). After an average follow-up time of 3.8 years from the start of treatment, 93% of the patients was examined by means of an individual subjective rating (score). In addition, a clinical examination was performed in 69% of the cases. According to the subjective personal rating (score) as well as the improvement in range of motion, moderate mobilisation led to better results than the mobilisation under anaesthesia.