Dose-temperature interactions in gamma-irradiated tendon allografts: A multidimensional analysis

This study evaluated the impact of cryoprotection temperature on the structural and biomechanical properties of gamma-irradiated human tendon allografts. Tendons were irradiated at 15 kGy or 25 kGy under three temperature conditions: -70°C, 0°C, or room temperature (RT). Structural integrity was assessed histologically and biochemically, while biomechanical properties were measured via tensile testing. Tendons irradiated at RT exhibited severe collagen disorganization and cellular loss, whereas those cryoprotected at -70°C retained aligned collagen structure with minimal disruption. Biomechanically, the -70°C groups showed significantly higher maximum stress than RT groups at both irradiation doses. Increasing irradiation dose exacerbated structural and mechanical degradation, but these effects were substantially mitigated by cryoprotection at -70°C. Thus, low-temperature protection during gamma irradiation is crucial for preserving the integrity of tendon allografts.