RESUMO
The convergence of cervical and trigeminal afferents on second-order neurons in the trigeminocervical nucleus may refer pain from the upper cervical spine into the head and face. Furthermore, "bi-directional interactions" between trigeminal and upper cervical afferents may also explain neck symptoms of trigeminal origin (e.g., migraine). It is known that cervicogenic headache sufferers present with several musculoskeletal changes including poor endurance of the deep cervical flexor muscles. These intrinsic muscles of the neck contribute to stabilization and protection of the cervical spine and are critical for the control of both intervertebral motion and the cervical lordosis. The purpose of this study was to determine whether the use of the PostureJac (SomatoCentric Systems, Inc., Toronto, Ontario, Canada), a posture support and exercise jacket, was effective in enhancing deep cervical muscle endurance. Forty-five (45) female subjects, between the ages of 18 and 40 years, were randomly assigned to three groups consisting of the no-treatment control, the treatment-control (table stabilization), and the experimental (PostureJac) group. The outcome measure of deep cervical flexor muscle endurance was based on the Flexor Endurance Test and was recorded in seconds. The results indicated that the PostureJac group was superior to the no-treatment control (p=.001) and the treatment-control (p=.004) groups in terms of increasing endurance of the deep cervical flexors. Consequently, the PostureJac may be a useful therapeutic tool in the management of cervicogenic headache and mechanical neck pain.