Shoulder biomechanics and the success of translational research.

In 2009, the International Shoulder Group (ISG) had the opportunity to propose to the readers of Medical and Biological Engineering and Computing a Special Issue on shoulder biomechanics. At that time, we pointed out that the field was evolving to include more applied research. After 4 years, we can confirm that impression: 10 out of 12 papers included in this second Special Issue deal with clinical related questions, through theoretical and experimental methodologies. This demonstrates that the translational research at the base of ISG foundation in 1989 is effective. We think that the papers of this issue will have an impact on clinics in general and on the treatment of work-related injuries and diseases in particular. Based on the statistics of the Italian Workers' Compensation Authority (INAIL), injuries at the shoulder are first in terms of average duration of "temporary total disability to work". Moreover, occupational diseases at the shoulder in the industrial and services sector represented 16 % of all occupational diseases in 2012, i.e., 46 % of those related to the upper limb. These data stress the need for specific interventions, with the contribution of both researchers and policy makers. Starting from the papers included here, we would encourage additional efforts on: (1) quantitative analysis of shoulder loading during tasks associated with musculoskeletal injuries, and ways to reduce that loading, (2) simple and effective tools to improve the diagnosis and outcome assessment of motion-related shoulder diseases, and (3) the development of rehabilitation treatments focused on occupational tasks, taking advantage of state-of-the-art biofeedback technologies, and exploiting the power of biomechanical models for muscle force prediction.