Neck Reflex Points: A New Clinical Test? Prevalence in Two Cohorts and Its Covariates

Background: Neck reflex points (NRPs) are 2 × 6 potentially tender areas of the neck, denominated NRP-C0 to NRP-C7. They are different from muscular trigger points and become tender in response to chronic trigeminal irritation. NRP examination has a high inter-rater reproducibility. We investigated the prevalence of NRPs in two populations to investigate their usefulness as a clinical test for trigeminal irritation. Methods: In total, 165 patients with chronic pain and 431 students were examined for NRP tenderness using a three-level pain scale: absent pain (PI = 0), mild tenderness (PI = 1), or marked tenderness (PI = 2). Results: In patients, we found more tender NRPs than in the student group (p < 0.001), and on the left side, more tender NRPs were found in NRP-C0-C4. Left and right NRPs appeared independently (kappa 0.1-0.4), except for NRP-C7 (kappa 0.55). Females had more tender NRPs (p < 0.001). Tenderness was independent of age, BMI, and pre-existing diseases. Conclusions: NRP tenderness occurs more frequently in patients than in students, independent from potential covariates. Our results, together with previous findings, support the use of NRP examination as a clinical test for chronic silent inflammation of the trigeminal region. These data provide a base for further studies investigating correlations of NRPs with clinical findings.