Isokinetic intervention in microtraumatic shoulder instability: an update.

Aim: Aim of the present study was to carry out a critical analysis of the use of isokinetic dynamometers for evaluation and rehabilitation in microtraumatic shoulder instability.
Methods: A non-systematic literature review was conducted on Medline using the following key words: "isokinetics", "shoulder instability", "evaluation", "rehabilitation". We also analyzed the related articles, and compiled a database of expert opinion.
Results: Despite a lack of consensus on testing modalities, lateral and medial rotator muscle strength can be safely and reliably assessed on isokinetic devices in subjects presenting with microtraumatic instability of the shoulder, before and after rehabilitation and/or surgery. There is considerable inter-individual variability in the results, leading to consider isokinetic testing as a useful examination before individualized rehabilitation. Its use as a muscle strengthening method in a global rehabilitation program seems interesting in order to correct rotator muscle strength deficiencies and/or asymmetries, which may be infra-clinical, even though strong scientific evidence is still lacking.
Conclusion: Isokinetics is a safe tool for evaluation and seems to be effective in rehabilitation for microtraumatic instability of the shoulder. It would, however, be necessary to standardize practices thanks to rigorous clinical studies, so as to determine precisely the indications of this technique in the comprehensive management of shoulder instability.