Injection in the cervical facet joint for shoulder pain with myofascial trigger points in the upper trapezius muscle.

摘要

The goal of this double-blinded, randomized, controlled study was to confirm the effectiveness of the cervical facet joint injection in treating shoulder pain with the myofascial trigger point in the upper trapezius muscle secondary to cervical facet lesion. Eighty-nine patients with chronic unilateral shoulder pain due to myofascial trigger points in the upper trapezius muscle received an injection to the C4-5 facet joint in the experimental group and to the corresponding unilateral multifidi muscle in the control group. Subjective pain intensity and pressure pain threshold of the myofascial trigger point were assessed, and the prevalence of endplate noise in the myofascial trigger point region was measured in 28 patients before, immediately after, and 1 month after the injection. Half of the patients in the experimental group, but none of the control patients, reported being completely pain free 1 month after the injection. Both the decrease in the pain intensity and the increase in pressure pain threshold were significantly more in the experimental group than in the control group either immediately or 1 month after the injection. There was no significant difference in the change of endplate noise prevalence between the 2 groups. This study demonstrates that intra-articular or peri-articular injection into the cervical facet joint region can effectively inactivate the upper trapezius myofascial trigger point secondary to the facet lesion.