Development of a Rehabilitation Apparatus for Frozen Shoulder Enabling Total Motion of Shoulder Complex

This article describes an apparatus developed by the authors as a substitution for physical therapists regarding mechanical movements in the rehabilitation of frozen shoulder. In particular, the performance of this apparatus is improved in comparison with existing methods in terms of the following two major points: (1) realization of individual rehabilitation for the patient’s scapula by an innovative parallel–serial hybrid linkage design and supporting parts that can fix and move the patient’s scapula; and (2) the addition of a “teaching” and “playback” mode to enable the apparatus to record the motion of rehabilitation, allowing it to be customized for each patient by physical therapists and reproduce the recorded motion accurately, thus freeing physical therapists from repetitive rehabilitation routines. With the introduction of the whole system, experimental results are shown and discussed to verify and evaluate the performance of the developed apparatus.