Mobility of the upper cervical spine and muscle performance of the deep flexors in women with temporomandibular disorders

Background Cervical spine disorders are frequently associated with temporomandibular disorders (TMDs). Although headache is common in TMD, few studies have considered headache regarding the functional performance of the cervical spine in TMD. Objectives To evaluate TMD subjects with and without self-reported headache, assess the active and passive range of motion (ROM) of the upper cervical spine (C1-C2) and performance of the deep cervical flexors, and evaluate the correlation of these outcomes with neck disability and temporomandibular pain. Methods In this cross-sectional study, we assessed 57 women (40 with TMDs and 17 without TMDs [controls]). The TMD group was divided into 25 and 15 patients with and without self-reported headache, respectively. We assessed the active and passive upper cervical ROMs using the flexion-rotation test (FRT) and muscle performance using the craniocervical flexion test (CCFT). The neck disability index questionnaire and visual analog scale were used to assess self-reported neck disability and temporomandibular pain, respectively. Results Compared to controls, all TMD subjects showed reduced cervical mobility on flexion/extension movements, reduced FRT findings and worse performance in CCFT (P < .05 all). Additionally, the CCFT and FRT findings were correlated with temporomandibular pain (r = .4 and .5, respectively) and neck disability (r = .3 and .4, respectively). Conclusion Women with TMDs, regardless of self-reported headaches, showed limited flexion/extension ROM, limited upper cervical spine (C1-C2) mobility and poor deep cervical flexor performance. Neck disability and temporomandibular pain showed a moderate correlation with the functional test findings, that is FRT and CCFT, in subjects with TMDs.