RESUMO
OBJECTIVES: To investigate pain, disability, and muscle function of the arm in medial epicondylitis and to compare the results with those in chronic lateral epicondylitis. DESIGN: Cross-sectional, case-control study. SETTING: University hospital clinic admitting chronic hand patients. PARTICIPANTS: Twenty-five patients with chronic unilateral medial epicondylitis and 25 age- and gender-matched patients with chronic unilateral lateral epicondylitis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: 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.