Normalized forces and active range of motion in unilateral radial epicondylalgia (tennis elbow)

Study Design: Single group pretest-posttest. Background: There is a lack of consensus concerning the preferred assessment and treatment for radial epicondylalgia. Objectives: Determine whether deficiencies in muscle force, joint range of motion, or painful force threshold are detected when measurements from the involved upper extremity are normalized to values from the uninvolved extremity. Methods and Measures: Ten patients (70% men) 42 +/- 7 years in age with unilateral radial epicondylalgia participated. The visual analog pain scale and 6 measurements involving either muscle force, joint range of motion, or painful force threshold were examined. Results: When comparing the initial assessments to final assessments, a significant improvement was found for the visual analog pain scale (5 +/- 3 vs 1 +/- 3) and for the following normalized scores: grip (78 +/- 26% vs 101 +/- 20%) and isometric wrist extension forces (68 +/- 24% vs 95 +/- 35%), painful force threshold over the lateral epicondyle (49 +/- 22% vs 94 +/- 14%), and active wrist extension range of motion (83 +/- 13% vs 96 +/- 10%). Conclusions: Normalized force and range of motion measurements following treatment for unilateral radial epicondylalgia are sensitive assessments of patient progress. In comparison with measurements of force and range of motion that are not adjusted to a baseline score, normalized measurements detect changes in patient responses when baseline scores vary.