Quantifying the stiffness of lumbar erector spinae during different positions among participants with chronic low back pain

• Published in: PloS one Vol. 17; no. 6; p. e0270286
• Main Authors: Li, Yapeng, Yu, Jiafeng, Zhang, Jun, Zhang, Zhijie, Wang, Xueqiang
• Format: Journal Article
• Language: English
• Published: San Francisco Public Library of Science 24.06.2022; Public Library of Science (PLoS)
• Subjects: Abdomen; Back pain; Backache; Biology and Life Sciences; Biomechanics; Care and treatment; Electromyography; Evaluation; Low back pain; Medicine and Health Sciences; Morphology; Muscles; Operators; Orthopedics; Pain; Physical Sciences; Posture; Prone position; Research and Analysis Methods; Sitting position; Statistical analysis; Stiffness; Ultrasonic imaging; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0270286

The purposes of this study were to (1) detect the intra- and inter-reliabilities of the lumbar erector spinae stiffness by MyotonPRO among participants with chronic lower back pain (CLBP); (2) compare the muscle stiffness between pain and non-pain sides during different positions; (3) explore the correlation between intensity of pain and muscle stiffness. Twenty participants with CLBP were recruited and the stiffness measurements were carried out by two experienced physiotherapists (operators â  and II). Each participant was evaluated by the operatorâ  in different postures (static prone and sitting). After a 5-day interval, the same participant was reassessed by the operatorâ  in the static prone posture. For the inter-rater reliability test, each participant was quantified by both operators once, with 30 minutes between the measurements on the same day. The intensity of pain was evaluated using a 0-10 visual analog scale (VAS). The intra- and inter-rater reliabilities were excellent (ICC = 0.88-0.99). The MDC values ranged from 25.03 to 86.26 N/m. Examples of Bland-Altman plots showed good agreement. The erector spinae stiffness on the painful sides was higher with a marked increase in the sitting position (P .05). The intensity of pain among adults with CLBP was not associated with muscle stiffness of the lumbar erector spinae muscle. Our findings indicated that the MyotonPRO is a feasible device in quantifying the stiffness of the lumbar erector spinae muscle in patients with CLBP. Meanwhile, the erector spinae stiffness on the painful sides was higher in the sitting when compared with the non-painful side.