International Consensus on Diagnostic Criteria and Clinical Considerations of Myofascial Trigger Points: A Delphi Study

The use of the term 'expert' occurs widely in healthcare research, in the context of national guidelines and consensus methods for the development of clinical protocols. Within consensus methods of research, especially Delphi panel techniques, the use of 'experts' is fundamental to reliability. Yet literature fails to debate the practicalities of defining 'experts' for use within Delphi panel research. This paper, by John Baker and colleagues, draws on methodological literature and discusses the concepts and elements of 'experts'. It concludes with recommendations for researchers to ensure experts for future Delphi research.

This paper describes the differences in the presence of myofascial trigger points (TrPs) in the upper trapezius, sternocleidomastoid, temporalis and suboccipital muscles between unilateral migraine subjects and healthy controls, and the differences in the presence of TrPs between the symptomatic side and the non-symptomatic side in migraine subjects. In addition, we assess the differences in the presence of both forward head posture (FHP) and active neck mobility between migraine subjects and healthy controls and the relationship between FHP and neck mobility. Twenty subjects with unilateral migraine without side-shift and 20 matched controls participated. TrPs were identified when there was a hypersensible tender spot in a palpable taut band, local twitch response elicited by the snapping palpation of the taut band and reproduction of the referred pain typical of each TrP. Side-view pictures were taken in both sitting and standing positions to measure the cranio-vertebral angle. A cervical goniometer was employed to measure neck mobility. Migraine subjects showed a significantly greater number of active TrPs (P<0.001), but not latent TrPs, than healthy controls. Active TrPs were mostly located ipsilateral to migraine headaches (P<0.01). Migraine subjects showed a smaller cranio-vertebral angle than controls (P<0.001), thus presenting a greater FHP. Neck mobility in migraine subjects was less than in controls only for extension (P=0.02) and the total range of motion in flexion/extension (P=0.01). However, there was a positive correlation between the cranio-vertebral angle and neck mobility. Nociceptive inputs from TrPs in head and neck muscles may produce continuous afferent bombardment of the trigeminal nerve nucleus caudalis and, thence, activation of the trigeminovascular system. Active TrPs located ipsilateral to migraine headaches might be a contributing factor in the initiation or perpetuation of migraine.