Elastic Modulus of Suboccipital Muscles, Cervical Range of Motion, and Forward Head Posture in Cervicogenic Headache

Although stiffness of neck muscles, the limitation of cervical range of motion (ROM), and forward head posture (FHP) are proposed as clinical characteristics of cervicogenic headache (CGH), adequate consistent data failed to support these characteristics. This study aims to compare the elastic modulus of suboccipital muscles, cervical ROM, and FHP between individuals suffering from CGH and healthy controls. In this cross-sectional study, 20 individuals with a history of CGH and 20 normal individuals participated. Sonography images and a universal goniometer (UG) were used to assess elastic modulus and cervical ROM, respectively. In addition, FHP was assessed based on measuring craniovertebral angle (CVA) using a digital imaging technique and also the distance of anterior tragus of the ear with the vertical line passed from anterior of lateral malleolus according to the Kendall and McCreary method. Elastic modulus of suboccipital muscles in the CGH group was significantly higher than that of the normal group (P=0.008). The two groups were not significantly different in terms of FHP. Moreover, ROM of cervical extension (P=0.035), right rotation (P=0.046), and left rotation (P=0.018) showed a significant reduction in the CGH group compared to the control group.  Suboccipital muscles are stiffer and ROM of cervical rotation and extension is smaller in CGH patients than the healthy controls, but FHP is not different between the groups, leading to diagnosing CGH and treatment.