Effects of kinesiophobia and pain on performance and willingness to perform jumping tests in Achilles tendinopathy: A cross-sectional study.

ABSTRACT

OBJECTIVES: Fear of movement may be a source of systemic bias in studies reporting functional deficits in patients with Achilles tendinopathy. The purpose of this study was to assess the effects of kinesiophobia on completion rate and performance on tests evaluating lower extremity function, while controlling for self-reported pain. DESIGN: Cross-sectional study; SETTING: Tendon research laboratory. PARTICIPANTS: Ninety-four participants with Achilles tendinopathy. MAIN OUTCOME MEASURES: Completion (yes/no) and performance (cm) on the counter-movement jump, hopping, and drop counter-movement jump. RESULTS: The models fit the data (R^2 = 0.81, both models). TSK score did not predict completion (beta = -0.01, 95% CI = -0.13 - 0.09, P = 0.74) but pain did (beta = -0.36, 95% CI = -0.53 to -0.19, P < 0.0001). TSK score did not predict performance (beta = -0.06, 95% CI = -0.14 - 0.003, P = 0.07), but pain did (beta = -0.15, 95% CI = -0.22 to -0.07, P < 0.0001). CONCLUSIONS: Kinesiophobia did not affect the physical performance tests in patients with Achilles tendinopathy. Measures of physical performance should be interpreted alongside self-reported pain.