Mariam A Ibrahim, Bassant Abdelhameed, Amir Beltagi, Mohammad Masoud, Sara Abdel-Aal Mohamed, Ahmed A Khalifa
In the cadaveric porcine knee model, the convection-based system achieved better early cooling than the circulating-pad systems, especially at the subdermal and intra-articular levels. These preliminary preclinical findings support the hypothesis that cooling modality might affect the depth and magnitude of thermal transfer under controlled laboratory conditions and require in vivo confirmation before clinical translation.
BACKGROUND: Postoperative inflammation after joint injury or surgery contributes to pain, edema, and delayed functional recovery. Cryotherapy is commonly used to alleviate pain and modulate inflammatory responses; however, the effectiveness of various cooling modalities in reducing temperatures in deeper periarticular and intra-articular tissues remains uncertain.
AIM: To compare the cooling performance of a convection-based cryotherapy system with two circulating-pad cooling systems in reducing temperature at various tissue depths.
METHODS: A cadaveric porcine knee model was used to assess comparative thermal transfer in periarticular tissues and the joint space. Thermocouples were placed at three sites: Subdermal, intramuscular, and intra-articular. Four experimental cooling conditions were evaluated by using: SootheAway 1 (SA1), SootheAway 2 (SA2), ThermoCuff (convection-based), and ambient control. Each cooling session lasted 60 minutes using a target coolant/air temperature of 35 °F (1.6 °C). The prespecified primary endpoint was the change in temperature at 20 minutes (ΔT20 = T20 - T0).
RESULTS: ThermoCuff produced a larger observed early temperature reduction through the tested compartments. At the subdermal level, ΔT20 was -14.8 °C with ThermoCuff compared with -8.4 °C for SA2, -3.9 °C for SA1, and -1.8 °C for ambient exposure. Intramuscular cooling was modest with ThermoCuff (-1.8 °C) and SA2 (-1.3 °C), whereas SA1 showed warming (+6.5 °C). At the intra-articular level, ThermoCuff achieved the highest temperature reduction (-10.0 °C), compared with -3.9 °C for SA2 and -3.3 °C for ambient exposure; SA1 showed warming (+4.8 °C).
CONCLUSION: In the cadaveric porcine knee model, the convection-based system achieved better early cooling than the circulating-pad systems, especially at the subdermal and intra-articular levels. These preliminary preclinical findings support the hypothesis that cooling modality might affect the depth and magnitude of thermal transfer under controlled laboratory conditions and require in vivo confirmation before clinical translation.