title: Chronic medial and lateral epicondylitis: a comparison of pain, disability, and function.
abstract: OBJECTIVE
  To investigate pain, disability, and muscle function of the arm in medial epicondylitis and to compare the results with those in chronic lateral epicondylitis.
  
  
  METHODS
  Cross-sectional, case-control study.
  
  
  METHODS
  University hospital clinic admitting chronic hand patients.
  
  
  METHODS
  Twenty-five patients with chronic unilateral medial epicondylitis and 25 age- and gender-matched patients with chronic unilateral lateral epicondylitis.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Pain drawing (PD) and a pain questionnaire with 7 items of pain and disability on visual analog scale (VAS). Dolorimeter measurements of pressure pain thresholds (PPT) on 3 defined cubital points. The isometric grip strength and isokinetic performance of wrist and forearm at a radial velocity of 90 degrees/s.
  
  
  RESULTS
  Patients with medial epicondylitis had significantly less pain under strain (6.7 vs 7.9cm on VAS, P =.03) and a smaller PD (1.9 vs 2.5, P =.02) than patients with lateral epicondylitis. The PPTs of medial epicondyles were 54% (P =.0000) lower in medial epicondylitis. In lateral epicondylitis, all 3 cubital points showed significant decreases in PPTs. The isometric grip strength (mean and maximal) decreased by 6.2% and 3.6%, compared with the patients' healthy arms (P =.03,.16) and by 11.4% and 8.9% (P =.008,.02), respectively, compared with the expected value; in lateral epicondylitis, the grip strength decreased by 11.8% and 10.6% (P =.005,.01) and by 15% and 14% (P =.003,.007), respectively, when compared with the expected grip strength. Peak torque and produced work in wrist flexion were significantly reduced by 13% and 17% (P =.005,.0001), respectively, in both diseases. In lateral epicondylitis, supination and pronation were also reduced by 10% and 15% (P =.03).
  
  
  CONCLUSIONS
  In chronic medial epicondylitis, muscle function and pain measures showed a lesser impaired function of the arm than in chronic lateral epicondylitis. The results may be useful in rehabilitation and treatment of epicondylitis.
authors.affiliation: Oulu Regional Institute of Occupational Health, Oulu University Hospital, Aapistie 1, FIN-90220 Oulu, Finland. tuomo.pienimaki@occuphealth.fi
authors.forename: Tuomo T
authors.initials: TT
authors.lastname: Pienimäki
authors.forename: Pertti T
authors.initials: PT
authors.lastname: Siira
authors.forename: Heikki
authors.initials: H
authors.lastname: Vanharanta
mesh_terms: D000328:Adult; D001132:Arm; D016022:Case-Control Studies; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005260:Female; D018737:Hand Strength; D006801:Humans; D008297:Male; D010147:Pain Measurement; D011795:Surveys and Questionnaires; D013716:Tennis Elbow / Q000503:physiopathology* / Q000534:rehabilitation; D014953:Wrist