Cervical Multifidus Morphology and Quality Are Not Associated with Clinical Variables in Women with Fibromyalgia: An Observational Study.

OBJECTIVE: Some studies have reported the presence of histological alterations, such as myofiber disorganization and abnormalities in the number and shape of mitochondria, in patients with fibromyalgia syndrome (FMS). Although Ultrasound imaging (US) is used to quantitatively characterize muscle tissues, US studies in patients with FMS are lacking. Therefore, we aimed to describe morphological and qualitative cervical multifidus (CM) muscle US features in women with FMS and to assess their correlation with clinical indicators. DESIGN: Observational study. SETTING: AFINSYFACRO Fibromyalgia Association (Madrid, Spain). SUBJECTS: Forty-five women with FMS participated. METHODS: Sociodemographic variables (e.g., age, height, weight, body mass index) and clinical outcomes (e.g., pain as assessed on a numerical pain rating scale, evolution time, pain-related disability as assessed by the Fibromyalgia Impact Questionnaire) were collected. Images were acquired bilaterally at the cervical spine (C4-C5 level) and measured by an experienced examiner for assessment of muscle morphology (e.g., cross-sectional area, perimeter, and shape) and quality (mean echo intensity and intramuscular fatty infiltration). Side-to-side comparisons and a correlational analysis were conducted. RESULTS: No significant side-to-side differences were found for morphology or quality features (P > 0.05). None of the clinical indicators were associated with US characteristics (all, P > 0.05). CONCLUSION: Our results showed no side-to-side differences for CM morphology and quality as assessed with US. No associations between CM muscle morphology or quality and Fibromyalgia Impact Questionnaire, pressure pain threshold, numerical pain rating scale score, or evolution time were observed. Our preliminary data suggest that muscle morphology is not directly related to pain and pain-related disability in women with FMS.

Pain Intensity and Sensory Perception of Tender Points in Female Patients with Fibromyalgia: A Pilot Study.

Fibromyalgia syndrome (FMS) is a condition that courses with chronic pain, fatigue, sleep disturbance, impaired quality of life and daily function. Due to the lack of blood, imaging or histological confirmatory tests, the diagnosis of FMS is based on the presence of widespread pain and presence of tender points (TPs). Our aim was to assess the pain pressure thresholds (PPTs) and subjective pain perception (SPP) of all 18 TPs while applying a normalized pressure in female patients with fibromyalgia. An exploratory descriptive pilot study was conducted in 30 female patients with FMS. Sociodemographic data (e.g., age, height, weight, and body mass index), clinical characteristics (e.g., years with diagnosis and severity of FMS), PPTs (assessed with an algometer), and SPP (assessed with a visual analogue scale) of all 18 TPs were collected. A comparative analysis side-to-side (same TP, left and right sides) and between TPs was conducted. No side-to-side differences were found (p < 0.05). Significant differences between all 18 TPs were found for PPTs (p < 0.0001), and SPP (p < 0.005) scores were found. The most mechanosensitive points were located in the second costochondral junction, the occiput, the trochanteric prominence; the most painful while applying a normalized pressure considering the TP and side were those located in the gluteus, trochanteric prominence, and supraspinatus. The current study describes PPTs and SPP, as assessed with algometry and visual analogue scale, respectively, of all 18 TPs in female patients with FMS. TPs exhibited significant PPTs and SPP differences between TP locations with no side-to-side differences.