Effects of thermal therapy in improving the passive range of knee motion: Comparison of cold and superficial heat applications

Objective: To assess the effect of applying a hot pack followed by a cold pack (COLD) on the passive range of knee flexion in subjects with restricted knee motion, specifically comparing this treatment to the application of a hot pack (HEAT) alone. Design: Seventy-one subjects were randomized into two groups to conduct a clinical randomized before-after trial. Interventions: Each subject received either (1) cold pack or (2) hot pack during passive knee joint stretching. Main outcome measure: Goniometry was used to measure the passive knee flexion at the baseline (KROM₁), before (KROM₂) and after (KROM₃) applications of a hot pack with/without a cold pack. Results: Repeated ANOVA measurements revealed a marked increase in the passive range of knee flexion in the two study groups (p < 0.001). Moreover, the paired t-test displayed statistical increments of knee flexion across the different measurement phases, except for the treatment phase without the cold pack. The range of knee flexion following the treatment with the application of a cold pack significantly exceeded that after treatment without a cold pack. Conclusion: Cold pack application had a limited but significant effect during mechanical stretching for restricted knee motion.