Cold is applied in arthritic joints to reduce the inflammatory activity of matrix-degrading enzymes and to ameliorate pain. The effect is based on vasoconstriction, leading to a downregulation of metabolic pathways. An analgesic component can be achieved after short-term cryotherapy by destimulating pain receptors in the cutis. Antiphlogistic effects are achieved after long-term cold treatment by inhibiting the metabolism in the inflammatory cells and repressing the release of lysosomal enzymes.1

Evaluation of the effect inside the joint is impossible without objective measurements. However, published reports are limited to clinical assessment, such as pain and disease activity scores.2 3 A reduction of blood flow has been reported in Achilles …