Pain sensitization and atrophy of deep cervical muscles in patients with chronic tension-type headache.

The aim of this study was to compare the pressure pain threshold and the thickness of the cervical muscles in patients with tension-type headache versus healthy participants. An observational, retrospective, cross-sectional study was conducted at the Universidad Europea de Madrid between May and June 2022. Adults aged 18-65 years with tension-type headache diagnosed for more than 6 months were compared to healthy controls. B-mode ultrasound imaging was employed to measure the thickness of the neck stabilizing muscles, longus colli, and multifidus at the C5 and C6 levels, respectively. pressure pain threshold measurements were assessed bilaterally in the following regions: upper trapezius, masseter, temporalis, anterior tibialis, and median nerve. A total of 40 participants (90% females; 36.3±12.9 years, BMI 24.2±3.7 kg/m2) participated in the study. Compared with the control group (n=20), participants in the tension-type headache group (n=20) presented statistically significant lower values in all pressure pain threshold measures. Additionally, the tension-type headache group presented statistically significant lower values in the thickness of the following muscles: right multifidus at rest (1.0±0.2 cm versus 1.3±0.2 cm; p<0.001), left multifidus at rest (1.1±0.1 cm versus 1.3±0.1 cm; p<0.001) and during contraction (1.2±0.1 cm versus 1.5±0.2 cm; p<0.001), left longus colli at rest (1.0±0.2 cm versus 1.2±0.1 cm; p=0.01) and during contraction (1.2±0.2 cm versus 1.4±0.1 cm; p<0.001), and right longus colli during contraction (1.2±0.2 cm versus 1.4±0.2 cm; p=0.02). This study concluded that patients with tension-type headache showed lower thickness and lower pressure pain threshold of cervical muscles compared to healthy controls.