Article

Cytokines in rotator cuff degeneration and repair.

MedSport, Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, MI 48106, USA.
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.] (impact factor: 1.93). 02/2012; 21(2):218-27. DOI:10.1016/j.jse.2011.09.020
Source: PubMed

ABSTRACT The pathogenesis of rotator cuff degeneration remains poorly defined, and the incidence of degenerative tears is increasing in the aging population. Rates of recurrent tear and incomplete tendon-to-bone healing after repair remain significant for large and massive tears. Previous studies have documented a disorganized, fibrous junction at the tendon-to-bone interface after rotator cuff healing that does not recapitulate the organization of the native enthesis. Many biologic factors have been implicated in coordinating tendon-to-bone healing and maintenance of the enthesis after rotator cuff repair, including the expression and activation of transforming growth factor-β, basic fibroblast growth factor, platelet-derived growth factor-β, matrix metalloproteinases, and tissue inhibitors of metalloproteinases. Future techniques to treat tendinopathy and enhance tendon-to-bone healing will be driven by our understanding of the biology of this healing process after rotator cuff repair surgery. The use of cytokines to provide important signals for tissue formation and differentiation, the use of gene therapy techniques to provide sustained cytokine delivery, the use of stem cells, and the use of transcription factors to modulate endogenous gene expression represent some of these possibilities.

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Keywords

basic fibroblast growth factor
 
biologic factors
 
cytokine delivery
 
cytokines
 
degenerative tears
 
Future techniques
 
gene therapy techniques
 
growth factor-β
 
incomplete tendon-to-bone healing
 
massive tears
 
matrix metalloproteinases
 
modulate endogenous gene expression
 
platelet-derived growth factor-β
 
rotator cuff
 
rotator cuff degeneration
 
rotator cuff healing
 
tendon-to-bone healing
 
tendon-to-bone interface
 
tissue formation
 
transcription factors