Myofascial trigger points in subjects presenting with mechanical neck pain: A blinded, controlled study

The aim of this study was to describe the differences in the presence of myofascial trigger points (TrPs) in the upper trapezius, sternocleidomastoid, levator scapulae and suboccipital muscles between patients presenting with mechanical neck pain and control healthy subjects. Twenty subjects with mechanical neck pain and 20 matched healthy controls participated in this study. TrPs were identified, by an assessor blinded to the subjects' condition, 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. The mean number of TrPs present on each neck pain patient was 4.3 (SD: 0.9), of which 2.5 (SD: 1.3) were latent and 1.8 (SD: 0.8) were active TrPs. Control subjects also exhibited TrPs (mean: 2; SD: 0.8). All were latent TrPs. Differences in the number of TrPs between both study groups were significant for active TrPs (P<0.001), but not for latent TrPs (P>0.5). Moreover, differences in the distribution of TrPs within the analysed cervical muscles were also significant (P<0.01) for all muscles except for both levator scapulae. All the examined muscles evoked referred pain patterns contributing to patients' symptoms. Active TrPs were more frequent in patients presenting with mechanical neck pain than in healthy subjects.