rESWT in Shoulder Periarthritis: Does the Protocol Intensity Matter?—A Quasi-Experimental Non-Randomized Comparative Study

Radial extracorporeal shockwave therapy (rESWT) is used in the rehabilitation of patients with shoulder periarthritis (SP) to promote tendon regeneration. This quasi-experimental non-randomized comparative study included 36 cases of SP, divided into two groups, and aimed to comparatively investigate the analgesic and functional effects of two different rESWT protocols. In Group One, the protocol involved an energy level of 210 J/session, a frequency of 10 Hz, and 2500 impulses per session. In Group Two, the protocol used an energy level of 190 J/session, a frequency of 10-15 Hz, and 2000 impulses per session. Treatments were administered over three sessions in Group One and five sessions in Group Two, with one-week intervals between sessions. Both rESWT protocols were combined with a physical therapy program consisting of ten daily sessions of analgesic physiotherapy and kinesiotherapy. Before and after the rehabilitation program, patients were assessed for pain intensity using the visual analog scale (VAS) and shoulder function using range of motion (ROM) measurements (via goniometry) and the Shoulder Pain and Disability Index (SPADI). Significantly better outcomes were observed in Group One (<i>p</i> < 0.001), particularly in terms of pain reduction and improvements in shoulder functionality, especially external rotation. These results support the effectiveness of the rESWT protocol used in Group One, which combined lower energy and frequency levels with a higher number of impulses over fewer sessions.