A great deal of research has focused upon the increasing incidence of and risk factors for injury in youth baseball players. However, little evidence exists to guide injury prevention strategies. Sakata and colleagues performed a prospective comparative study. There were 275 baseball players age 8 to 11 [years who] were divided into a control group and a group that was instructed in a combination of nine stretching and nine strengthening exercises that included the wrist, elbow, shoulder, core and hips. An a priori power analysis suggested 304 subjects would be necessary. Players were asked to complete the program at least once a week and compliance was 57.4% via self-report.
At 1-year, the exercise group had significantly lower rates of medial elbow injury and significantly better total range of shoulder rotation. In a multivariate analysis, increased shoulder total rotation, increased nondominant hip internal rotation and decreased thoracic kyphosis predicted lower rates of medial elbow injury.
The study is weakened by selection bias — 28% of the original group was excluded due to prior shoulder or elbow pain and an additional 15% were excluded due to loss to follow-up. The study is not blinded or randomized. Given cultural differences between Japan and the United States, it remains unclear whether these findings will be generalizable and thus the findings will need to be confirmed before this program can be recommended. Overall, the study is innovative and provides an exciting new potential avenue for injury prevention.
Ahmad CS, et al. Am J Sports Med. 2017;doi:10.1177/0363546516667503.
Chalmers PN, et al. Arthroscopy. 2015;doi:10.1016/j.arthro.2015.03.017.
Ciccotti MG, et al. Am J Sports Med. 2017;doi:10.1177/0363546517706964.
Erickson BJ, et al. Am J Sports Med. 2015;doi:10.1177/0363546515580304.
Erickson BJ, et al. Arthroscopy. 2016;doi:10.1016/j.arthro.2015.11.051.
Hodgins JL, et al. Am J Sports Med. 2016;doi:10.1177/0363546515622407.
Saper MG, et al. Am J Sports Med. 2017;doi:10.1177/0363546517734172.
Sakata J, et al. Am J Sports Med. 2017;doi:10.1177/0363546517738003.
Skillington SA, et al. Am J Sports Med. 2017;doi:10.1177/0363546516688657.
Peter N. Chalmers, MD
Shoulder and Elbow Surgery
University of Utah Health
Salt Lake City
Disclosures: Chalmers reports no relevant financial disclosures.