The crossed extensor reflex is an important spinal reflex that assists in withdrawing a limb away from a painful stimulus [1]. When a noxious stimulus is applied to one leg, such as stepping on a tack, it activates nociceptive afferent fibers that synapse on interneurons in the ipsilateral side of the spinal cord [1][3]. These interneurons then inhibit alpha motor neurons innervating the ipsilateral flexor muscles, causing them to relax [1]. Simultaneously, the interneurons excite alpha motor neurons innervating the contralateral extensor muscles, causing them to contract and extend the opposite leg [1][4]. This crossed excitation and inhibition serves to increase the distance between the site of noxious stimulation and the body to promote withdrawal [1][2]. Variations like the double crossed extensor reflex can produce alternating arm movements for additional stabilization [1]. The crossed extensor reflex is suppressed in normal adults but is exaggerated in spinal cord injury patients, resulting in abnormal movements to stimuli [2][5]. Overall, this reflex allows coordinated, bilateral responses to unilateral painful stimuli for protection.