The CPM paradigm has shown good intrasession reliability (ICC>0.75). 37 Nociceptive flexor withdrawal reflex (NFR): NFR is a measure of central sensitisation and descending pain control systems, and was used in previous studies investigating central sensitisation in knee OA. 38 Surface stimulating electrodes will be positioned at a retromalleolar location along the sural nerve on the side of the painful knee.
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