Thermal profiles over the Patella tendon in a cohort of non-injured collegiate athletes over the course of a cross-country season

Abstract

Objectives: To determine normal temperatures over the Patella tendon over eleven weeks.

Design: A prospective cohort study with eleven weeks of observation.

Setting: University's Human Biomechanics and Physiology Laboratory.

Participants: Male or female collegiate runners running at least 25 miles per week who did not report pain in the region of the Patella tendon over 11 weeks of data collection.

Main outcome measures: Thermal images taken at the same time and day of the week, were used to measure the temperature of the skin over the Patella tendon.

Results: Eighteen athletes were eligible for analysis. The mean temperature of the Patella tendon was 30.13 °C (SD = 1.51 °C). Patella tendon temperature changes over time were insignificant (right p = 0.66, left p = 0.90) with ICC right = 0.92, left = 0.94. Mean temperature difference side to side was 0.14 °C (SD = 0.60 °C). Mixed-model Linear regression for mean temperature differences found the effect of (i) time (t = 0.39, p = 0.70, df = 361) and (ii) side (t = -0.89, p = 0.38, df = 361) to be insignificant.

Conclusions: This is the first report of normal thermal profiles of collegiate runners over an extended period. Temperature variation above 1.20 °C may represent an abnormal asymmetry in the running population. Variations in Patella tendon temperatures left to right, and over time were not significant.

Keywords: Medical infrared thermography; Patella tendon; Skin temperature; Tendinopathy.