105 87

Cited 139 times in

Hamstring contractures in children with spastic cerebral palsy result from a stiffer extracellular matrix and increased in vivo sarcomere length.

 Lucas R. Smith  ;  Ki S. Lee  ;  Richard L. Lieber  ;  Henry G. Chambers  ;  Samuel R.Ward 
 Journal of Physiology, Vol.589(pt 10) : 2625-2639, 2011 
Journal Title
 Journal of Physiology 
Issue Date
Cerebral palsy (CP) results from an upper motoneuron (UMN)lesion in the developing brain. Secondary to the UMNl esion,which causes spasticity, is a pathological response by muscle - namely, contracture. However, the elements within muscle that increase passive mechanical stiffness, and therefore result in contracture, are unknown. Using hamstring muscle biopsies from pediatric patients with CP (n =33) and control (n =19) patients we investigated passive mechanical properties at the protein, cellular, tissue and architectural levels to identify the elements responsible for contracture. Titin isoform, the major load-bearing protein within muscle cells, was unaltered in CP. Correspondingly, the passive mechanics of individual muscle fibres were not altered. However, CP muscle bundles, which include fibres in their constituent ECM, were stiffer than control bundles. This corresponded to an increase in collagen content of CP muscles measured by hydroxyproline assay and observed using immunohistochemistry. In vivo sarcomere length of CP muscle measured during surgery was significantly longer than that predicted for control muscle. The combination of increased tissue stiffness and increased sarcomere length interact to increase stiffness greatly of the contracture tissue in vivo. These findings provide evidence that contracture formation is not the result of stiffening at the cellular level, but stiffening of the ECM with increased collagen and an increase of in vivo sarcomere length leading to higher passive stresses.
Appears in Collections:
1. Journal Papers (연구논문) > 1. College of Medicine (의과대학) > Dept. of Orthopedic Surgery (정형외과학교실)
Yonsei Authors
이기석(Lee, Ki Seok)
사서에게 알리기
Files in This Item:
T201101391.pdf Download
RIS (EndNote)
XLS (Excel)


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.