title: Effect of lateral epicondylosis on grip force development.
abstract: METHODS
  Case-Control.
  
  
  BACKGROUND
  Although it is well known that grip strength is adversely affected by lateral epicondylosis (LE), the effect of LE on rapid grip force generation is unclear.
  
  
  OBJECTIVE
  To evaluate the effect of LE on the ability to rapidly generate grip force.
  
  
  METHODS
  Twenty-eight participants with LE (13 unilateral and 15 bilateral LE) and 13 healthy controls participated in this study. A multiaxis profile dynamometer was used to evaluate grip strength and rapid grip force generation. The ability to rapidly produce force is composed of the electromechanical delay and rate of force development. Electromechanical delay is defined as the time between the onset of electrical activity and the onset of muscle force production. The Patient-rated Tennis Elbow Evaluation (PRTEE) questionnaire was used to assess pain and functional disability. Magnetic resonance imaging was used to evaluate tendon degeneration.
  
  
  RESULTS
  LE-injured upper extremities had lower rate of force development (50 lb/sec, confidence interval [CI]: 17, 84) and less grip strength (7.8 lb, CI: 3.3, 12.4) than nonnjured extremities. Participants in the LE group had a longer electromechanical delay (- 59% , CI: 29, 97) than controls. Peak rate of force development had a higher correlation (r = 0.56; p<0.05) with PRTEE function than grip strength (r = 0.47; p<0.05) and electromechanical delay (r = 0.30; p>0.05) for participants with LE. In addition to a reduction in grip strength, those with LE had a reduction in rate of force development and an increase in electromechanical delay.
  
  
  CONCLUSIONS
  Collectively, these changes may contribute to an increase in reaction time, which may affect risk for recurrent symptoms. These findings suggest that therapists may need to address both strength and rapid force development deficits in patients with LE.
  
  
  METHODS
  3B.
authors.affiliation: Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, USA.
authors.forename: Amrish O
authors.initials: AO
authors.lastname: Chourasia
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Buhr
authors.forename: David P
authors.initials: DP
authors.lastname: Rabago
authors.forename: Richard
authors.initials: R
authors.lastname: Kijowski
authors.forename: Curtis B
authors.initials: CB
authors.lastname: Irwin
authors.forename: Mary E
authors.initials: ME
authors.lastname: Sesto
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004550:Elbow / Q000473:pathology / Q000503:physiopathology; D004576:Electromyography; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D053581:Muscle Strength Dynamometer; D010147:Pain Measurement; D013716:Tennis Elbow / Q000503:physiopathology*