title: The Elbow-EpiTrainer: a method of delivering graded resistance to the extensor carpi radialis brevis. Effectiveness of a prototype device in a healthy population.
abstract: BACKGROUND
  Tennis elbow or lateral epicondylopathy (LE) is experienced as the lateral elbow has a reported prevalence of 1.3%, with symptoms lasting up to 18 months. LE is most commonly attributed to tendinopathy involving the extensor carpi radialis brevis (ECRB) tendon. The aim of tendinopathy management is to alleviate symptoms and restore function that initially involves relative rest followed by progressive therapeutic exercise.
  
  
  OBJECTIVE
  To assess the effectiveness of two prototype exercises using commonly available clinical equipment to progressively increase resistance and activity of the ECRB.
  
  
  METHODS
  Eighteen healthy participants undertook two exercise progressions. Surface electromyography was used to record ECRB activity during the two progressions, involving eccentric exercises of the wrist extensors and elbow pronation exercises using a prototype device. The two progressions were assessed for their linearity of progression using repeated ANOVA and linear regression analysis. Five participants repeated the study to assess reliability.
  
  
  RESULTS
  The exercise progressions led to an increase in ECRB electromyographic (EMG) activity (p<0.001). A select progression of exercises combining the two protocols increased EMG activity in a linear fashion (p<0.001). The ICC values indicated good reliability (ICC>0.7) between the first and second tests for five participants.
  
  
  CONCLUSIONS
  Manipulation of resistance and leverage with the prototype exercises was effective in creating significant increases of ECRB normalised EMG activity in a linear manner that may, with future research, become useful to clinicians treating LE. In addition, between trial reliability for the device to generate a consistent load was acceptable.
authors.affiliation: Department of Physiotherapy, Imperial College Healthcare NHS Trust, London, UK.
authors.forename: Rishi
authors.initials: R
authors.lastname: Navsaria
authors.affiliation: Department of Allied Health Professions and Midwifery, University of Hertfordshire, Hertfordshire, UK.
authors.forename: Dionne M
authors.initials: DM
authors.lastname: Ryder
authors.affiliation: Department of Allied Health Professions and Midwifery, University of Hertfordshire, Hertfordshire, UK.
authors.forename: Jeremy S
authors.initials: JS
authors.lastname: Lewis
authors.affiliation: Department of Physiotherapy, Imperial College Healthcare NHS Trust, London, UK.
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Alexander
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D004551:Elbow Joint / Q000502:physiology; D004576:Electromyography; D004867:Equipment Design; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D011403:Pronation / Q000502:physiology; D055070:Resistance Training / Q000295:instrumentation / Q000379:methods*; D013484:Supination / Q000502:physiology; D013716:Tennis Elbow / Q000534:rehabilitation*; D014955:Wrist Joint / Q000502:physiology; D055815:Young Adult
keywords: Eccentric exercise; Elbow injuries; Exercise; Tendons