TITLE

Shoulder Strength in Asymptomatic Individuals with Intact Compared with Torn Rotator Cuffs

AUTHOR(S)
Kim, H. Mike; Teefey, Sharlene A.; Ari Zelig; Galatz, Leesa M.; Keener, Jay D.; Yamaguchi, Ken
PUB. DATE
February 2009
SOURCE
Journal of Bone & Joint Surgery, American Volume;Feb2009, Vol. 91-A Issue 2, p289
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Background: Normative data are essential to the evaluation of shoulder function. The purposes of this study were to establish a normative database of isometric shoulder strength measured in asymptomatic individuals verified to have intact rotator cuffs and to determine the effect of asymptomatic rotator cuff tears on shoulder strength. Methods: Two hundred and thirty-seven volunteers with no shoulder pain or history of shoulder injury were screened with ultrasonography bilaterally for rotator cuff tears and then underwent isometric strength measurements for abduction in the scapular plane and external rotation. Statistical analysis was performed to evaluate the effect of age, body habitus, hand dominance, and the presence of a rotator cuff tear on shoulder strength. Results: Of the 237 volunteers, forty-one were found to have a torn rotator cuff in at least one shoulder. The prevalence of rotator cuff tears was 0% for the subjects between forty and forty-nine years old; 10%, between fifty and fifty-nine years old; 20%, between sixty and sixty-nine years old; and 40.7% for those seventy years old or older. Both abduction strength and external rotation strength in the male subjects showed an age-dependent decrease, whereas only abduction strength showed an age-dependent decrease in the female subjects. In multiple regression analysis, age and weight were the most important predictors of abduction strength and external rotation strength, respectively. In the shoulders with a large-to-massive full-thickness rotator cuff tear, abduction strength was significantly decreased (p= 0.007). Additionally, the ratio of abduction strength to external rotation strength was significantly decreased in the shoulders with a large-to-massive full- thickness tear compared with the shoulders with an intact rotator cuff (p < 0.001). Conclusions: There is a high prevalence of rotator cuff tears in elderly asymptomatic individuals. Asymptomatic shoulders with a large-to-massive full-thickness rotator cuff tear have significantly decreased abduction strength. When there is a substantial decrease in abduction strength in relation to external rotation strength, the presence of an asymptomatic full-thickness tear should be suspected in that shoulder. Previous studies establishing normative values for isometric shoulder strength may have been skewed by the presence of asymptomatic rotator cuff tears in elderly subgroups.
ACCESSION #
36627708

 

Related Articles

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics