The increased motion of lumbar induces ligamentum flavum hypertrophy in a rat model

• Published in: BMC musculoskeletal disorders Vol. 22; no. 1; p. 334
• Main Authors: Wang, Baojian, Gao, Chunyu, Zhang, Ping, Sun, Wu, Zhang, Jingru, Gao, Jinghua
• Format: Journal Article
• Language: English
• Published: England BioMed Central 06.04.2021; BMC
• Subjects: Animals; Collagen; Etiology; Experimental study; Fibers; Fibrotic factor; Gene expression; Hypertrophy; IL-1β; Increased motion; Inflammation; Inflammatory factor; Intervertebral discs; Laboratory animals; Ligamentum flavum; Ligamentum Flavum - diagnostic imaging; Lumbar Vertebrae - diagnostic imaging; Lumbosacral Region; Male; Medical research; Monoclonal antibodies; Musculoskeletal diseases; Rats; Rodents; Spinal Stenosis; Surgery; Transforming growth factor-b1; Tumor necrosis factor-TNF; Tumor necrosis factor-α; Beijing China; United States > US; China; Immunohistochemistry; Real‐time PCR; Fibrotic factor; Rat model; Inflammatory factor; Lumbar degenerative disease; Experimental study; Increased motion; Ligamentum flavum; Masson trichrome staining; Hypertrophy
• ISSN: 1471-2474; 1471-2474
• DOI: 10.1186/s12891-021-04203-x

The purpose of this study was to establish a novel rat model for ligamentum flavum (LF) hypertrophy using increased motion of lumbar and to elucidate the etiology of (LFH). A total number of 30 male rats were used. The increased motion of lumbar was induced by surgical resection of L5/6 posterior elements (n = 15). The other rats underwent a sham operation (n = 15). After 8 weeks, all rats were taken lateral plain X-rays. The LF from L5/6 in both groups were harvested to investigate histological, immunohistological, and real-time PCR analysis. According to radiological results, the disc height ratio, flexion ratio, and extension ratio were larger in the rats in the experimental group than that of in the sham group. The HE staining showed that the LF thickness in the experimental group significantly increased in comparison to the sham group. The Masson trichrome staining showed that the ratio of elastic fibers to collagen fibers in experimental group was lower than that in the sham group. The protein and gene expression of TGF-β1, TNF-α, IL-1β, and Col 1 were significantly higher in the experimental group than that in the sham group. A relatively safe, simple, and rapid rat model of LFH using increased motion of lumbar was established. The increased motion of lumbar could lead to high expression of inflammatory and fibrotic factors in LF, causing the accumulation of collagen fibers and decreasing of elastic fibers.