[Use of continuous passive motion in inpatient rehabilitation after shoulder replacement-a retrospective study]

Continuous passive motion (CPM) devices are widely used in the therapy of joint diseases. While the use of CPM after arthroplasty of the knee is already well evaluated, this study focuses on the use of CPM-devices after shoulder arthroplasty.

In this retrospective analysis, 110 patients were examined for changes in pain perception and use of pain medication. For 45 of them, the development of the active range of motion and the ability to perform the superior and inferior Apley scratch test were investigated after regular CPM treatment as part of a multimodal rehabilitation program following shoulder arthroplasty. Additionally, the potential influence of the initiation time of CPM treatment was statistically analyzed using the Wilcoxon signed-rank test for paired samples and Pearson's rank correlation analysis.

Using CPM as a component in a rehabilitation treatment concept led to a reduction in pain perception and the need for pain medication. Furthermore, an improvement in the range of motion, was observed. A significant correlation between the timing of the therapy's initiation and the outcome at the end of rehabilitation could not be demonstrated, but the frequency of application correlated positively with changes in the range of motion.

The results of this study imply potential for benefits from the use of CPM devices after shoulder replacement surgery as part of rehabilitation. Due to the study design without any control group, a clear distinction between the rehabilitation without intervention, the effect of a multimodal therapy, and the specific effect of CPM therapy is not possible. Furthermore, it is not possible to determine what effect is attributable to CPM therapy and what potential advantages may exist, compared to manual mobilization or purely functional exercises. These questions, as well as aspects of cost-effectiveness, should be investigated in further studies.