Approximately 83% of patients with fibromyalgia demonstrate visually straight cervical spines, according to data published in the Journal of Clinical Rheumatology.
The researchers added that the loss of cervical spine curvature is approximately 6.5 times greater in those with fibromyalgia compared with control individuals.
“It caught my eye a long time ago when I visualized radiographs of fibromyalgia patients,” Robert S. Katz MD, of Rush Medical College, in Chicago, told Healio. “The straight neck seemed to be so common that we decided to study it.”
To examine the cervical curvature via radiographs of patients with fibromyalgia, Katz and colleagues conducted a medical records review study. The researchers retrospectively analyzed 270 lateral view cervical spine radiographs of adult female patients with neck pain from 2015 to 2018, using the Cobb angle measurement for cervical lordotic curve.
In total, 155 of the patients, with a mean age of 44.8 years, met the American College of Rheumatology guidelines for fibromyalgia, while 115 patients, with a mean age of 44 years, met the guidelines for another rheumatic disease and were used as a control group. Katz and colleagues performed the statistical analysis using SPSS version 22.0. The researchers defined a visually straight cervical spine as one with a 10-degree Cobb angle measurement.
According to the researchers, patients with fibromyalgia demonstrated a mean curvature of 6.4 ± 5.2 degrees, compared with 13.8 ± 7.4 degrees in the control group (P < .001). Additionally, 83.2% of patients with fibromyalgia had a 10-degree or less cervical Cobb angle, compared with 32.2% in the control group (P < .001). Moreover, the researchers found that 50.3% of patients with fibromyalgia had a Cobb angle measurement of 5 degrees or less, compared to just 7.8% of the control group (P < .001).
In addition, muscle pressure was three times higher in patients with fibromyalgia, compared with the control group, the researchers wrote.
“Very little has been observed about the diagnostic markers in fibromyalgia,” Katz said. “Increased muscle pressure and straight neck are two of them that I believe are important in assisting with the diagnosis and also in suggesting a potential etiology and therefore treatment.”