From: Man Ther. 2009 Dec;14(6):696-701. Epub 2009 Jul 25
Deep cervical flexor muscle activation is impaired with neck pain. This study investigated the effects of low load cranio-cervical flexion and neck flexor strengthening exercises on spatial and temporal characteristics of deep cervical flexor muscle activation during a neck movement task and a task challenging the neck’s postural stability.
Forty-six chronic neck pain subjects were randomly assigned to an exercise group and undertook a 6-week training program. Electromyographic activity was recorded from the deep cervical flexor muscle, sternocleidomastoid and anterior scalene muscles pre and post intervention during the cranio-cervical flexion test and during perturbations induced by rapid, unilateral shoulder flexion and extension. Cranio-cervical flexion neck exercises for training increased deep cervical flexor muscle electromyographic amplitude and decreased sternocleidomastoid and anterior scalene electromyographic amplitude across all stages of the cranio-cervical flexion test.
No change occurred in deep cervical flexor muscle electromyographic amplitude following strength training. There was no significant between group difference in pre-post intervention change in relative latency of deep cervical flexor muscle but a greater proportion of the cranio-cervical flexion group shortened the relative latency between the activation of the deltoid and the deep cervical flexor muscle during rapid arm movement compared to the strength group. Specific low load cranio-cervical flexion exercise changes spatial and temporal characteristics of deep cervical flexor muscle activation which may partially explain its efficacy in rehabilitation.
