Chronic tension type headache: what is new?
From: Curr Opin Neurol. 2009 Mar 18. [Epub ahead of print]
This review discusses current data on nosological boundaries related to diagnosis, pathophysiology and therapeutic strategies in chronic tension type headache. Diagnostic criteria of chronic tension type headache should be adapted to improve its sensitivity against migraine. It seems that mechanical pain sensitivity is a consequence and not a causative factor of chronic tension type headache. Recent evidence is modifying previous knowledge about relationships between muscle tissues and chronic tension type headache, suggesting a potential role of muscle trigger points in the genesis of pain. An updated pain model suggests that headache perception can be explained by referred pain from trigger points in the craniocervical neck muscles, mediated through the spinal cord and the trigeminal nucleus caudalis rather than only tenderness of the neck muscles themselves.
Different therapeutic strategies for chronic tension type headache; pharmacological, physical therapy, psychological and acupuncture, are generally used. The therapeutic efficacy of nonsteroidal anti-inflammatory drugs remains incomplete. The tricyclic antidepressants are the most used first-line therapeutic agents for chronic tension type headache. Surprisingly, few controlled studies have been performed and not all of them have found an efficacy superior to placebo. Further, there is insufficient evidence to support or refute the efficacy of physical therapy in chronic tension type headache. Although there is an increasing scientific interest in chronic tension type headache, future studies incorporating subgroups of patients who will likely to benefit from a specific treatment (clinical prediction rules) should be conducted.
In Eur J Pain. 2007 May;11(4):475-82, it was noted that referred pain from trapezius muscle trigger points shares similar characteristics with chronic tension type headache. The results showed that manual exploration of trigger points in the upper trapezius muscle elicited referred pain patterns in both chronic tension type headache patients and healthy subjects. In chronic tension type headache patients, the evoked referred pain and its sensory characteristics shared similar patterns as their habitual headache pain, consistent with active trigger points.
In Pain Med. 2009 Jan;10(1):43-8, referred pain elicited by manual exploration of the lateral rectus muscle in chronic tension type headache. In some patients with chronic tension type headache, the manual examination of lateral rectus muscle trigger points elicits a referred pain that extends to the supraorbital region or the homolateral forehead. Nociceptive inputs from the extraocular muscles may sustain the activation of trigeminal neuron, thus sensitizing central pain pathways and exacerbating headache.
According to Headache. 2007 May;47(5):662-72, Active trigger points in the upper trapezius, sternocleidomastoid, and temporalis muscles were more common in tension headache subjects than in healthy controls, although trigger point activity was not related to any clinical variable concerning the intensity and the temporal profile of headache, tension headache patients showed greater forward head posture and lesser neck mobility than healthy controls, although both disorders were not correlated with headache parameters.
