title: [Effect of lumbar dorsal muscle injuries on lumbar vertebral bone quality of rat].
abstract: Objective:To explored the effects of lumbar dorsal muscle damage on local lumbar vertebral bone quality.Methods:Thirty SD female rats, at age of 20 weeks, were randomly divided into three groups: control group, or say pseudo surgery group, an incision in the back were performed as CNT; bilateral erector spinal muscle group in which group bilateral lumbar erector spinal muscle were removed as RESM; castration group in which bilateral ovaries were resected as OVX.After three months, bone mineral density, microscopic CT and vertebral compression test were taken in lumbar vertebral (L4-6) in turn.Results:After three months bone mineral density in RESM group was obviously lower than the control group [(0.211±0.028) g/cm2vs(0.253±0.021) g/cm2,P<0.01], however, there was no significant difference between OVX and RESM[(0.197±0.015) g/cm2vs(0.211±0.028) g/cm2,P>0.05]. In microscopic CT three-dimensional reconstruction and bone histomorphometry analysis, compared with control group CNT , in the experimental groups OVX and RESM, bone trabecula of vertebral bodies were more sparse, the overall number and interconnection of trabecula were less.Especially in the OVX, osteoporotic trend of trabecular network trend is more obvious.In vertebral compression test, the maximum load, energy absorption, the maximum stress and elastic modulus in both OVX and RESM were significantly reduced (P<0.01). In the RESM the above four biomechanical parameters were significantly higher than those of OVX (P<0.05).Conclusion:Integrity and vigor of paravertebral muscles would be of great significance to maintain adjacent vertebral bone quality.Resection of lumbar dorsal muscles could lead to a significant decrease of local vertebral bone quality.Damage and atrophy of lumbar dorsal muscle could cause osteoporosis of vertebral bodies.
authors.affiliation: Department of Orthopaedics, Shanghai General Hospital of Nanjing Medical University, Shanghai 201620, China.
authors.forename: X P
authors.initials: XP
authors.lastname: Wang
authors.forename: S J
authors.initials: SJ
authors.lastname: Wang
authors.forename: P
authors.initials: P
authors.lastname: Yan
authors.forename: L L
authors.initials: LL
authors.lastname: Zhu
authors.forename: M Q
authors.initials: MQ
authors.lastname: Li
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Bian
authors.forename: J W
authors.initials: JW
authors.lastname: Tian
mesh_terms: D000818:Animals; D015519:Bone Density; D001851:Bone Diseases, Metabolic; D005260:Female; D008159:Lumbar Vertebrae; D010024:Osteoporosis; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley; D016103:Spinal Fractures; D014057:Tomography, X-Ray Computed