title: Upper extremity strength characteristics in female recreational tennis players with and without lateral epicondylalgia.
abstract: METHODS
  Descriptive, cross-sectional.
  
  
  OBJECTIVE
  To compare static strength characteristics of the upper extremity musculature in female recreational tennis players with lateral epicondylalgia to those of nonsymptomatic tennis players and a control group of women who did not play tennis.
  
  
  BACKGROUND
  There is a paucity of research describing the relationship between lateral epicondylalgia and strength characteristics of the upper extremity musculature, despite the functional relationship between the shoulder, elbow, and wrist.
  
  
  METHODS
  Sixty-three women were recruited into 3 groups (n = 21 per group): symptomatic tennis players (STP) with lateral epicondylalgia, nonsymptomatic tennis players, and controls. Data collection was performed during a single session, during which the strength of selected muscle groups of the dominant upper extremity was measured using a combination of force transducers. Strength ratios of selected muscle groups were then calculated.
  
  
  RESULTS
  The STP group reported median pain level of 3/10 on a numeric pain rating scale and a symptom duration of 16 weeks. The STP group had weaker lower trapezius strength (mean difference, -9.0 N; 95% confidence interval [CI]: -13.5, -4.4) and wrist extensor strength (-12.7 N; 95% CI: -24.4, -1.1), and a higher shoulder internal/external rotation strength ratio (0.19; 95% CI: 0.02, 0.35) and upper/lower trapezius strength ratio (1.32; 95% CI: 0.41, 2.23), compared to those of the nonsymptomatic group. Compared to the control group, the STP group demonstrated a significantly higher shoulder internal/external rotation strength ratio (0.21; 95% CI: 0.04, 0.38) and wrist flexion/extension strength ratio (0.14; 95% CI: 0.01, 0.27).
  
  
  CONCLUSIONS
  In this group of recreational female tennis players, significant differences in strength and strength ratio characteristics were identified. Although the design of the study precludes establishing a cause-and-effect relationship, the results suggest further study and treatment of the muscle groups of interest.
authors.affiliation: Department of Physical Therapy, Mercer University, 3001 Mercer University Drive, Atlanta, GA 30341, USA. lucado_am@mercer.edu
authors.forename: Ann M
authors.initials: AM
authors.lastname: Lucado
authors.forename: Morey J
authors.initials: MJ
authors.lastname: Kolber
authors.forename: M Samuel
authors.initials: MS
authors.lastname: Cheng
authors.forename: John L
authors.initials: JL
authors.lastname: Echternach
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000503:physiopathology; D013715:Tennis / Q000293:injuries* / Q000502:physiology; D013716:Tennis Elbow / Q000209:etiology* / Q000503:physiopathology; D034941:Upper Extremity / Q000503:physiopathology*; D055815:Young Adult