The role of myofascial trigger points in musculoskeletal pain syndromes of the head and neck.

Neck and head pain syndromes are common problems seen in clinical practice. Pain features of commonly designated idiopathic neck pain and some primary headaches (ie, tension-type headache or migraine) fit the descriptions of referred pain originating in muscle trigger points (TrPs). This article discusses the scientific evidence supporting the role of muscle TrPs in chronic musculo-skeletal disorders of the neck and head. The relevance of referred pain elicited by muscle TrPs in patients with neck pain has been investigated in few studies. Some authors found that both muscle TrPs in neck-shoulder muscles and cervical joint dysfunctions contribute at the same time to neck pain perception. Furthermore, it seems that referred pain originated in muscle TrPs could also contribute to neck symptoms perceived by subjects after a rear-end crash. In addition, several recent studies reported that both TTH and migraine are associated with referred pain from TrPs in the suboccipital, upper trapezius, sternocleidomastoid, temporalis, or superior oblique muscles. Referred pain elicited by active TrPs mimics the pain areas observed during head pain attacks in these primary headaches. Based on available data, it seems that the pain profile of neck and head syndromes may be provoked referred pain from TrPs in the posterior cervical, head, and shoulder muscles. Additional studies are needed to delineate more information on the relation between muscle TrPs and musculoskeletal pain syndromes of the head and neck.