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Changes in collagen matrix composition in human posterior tibial tendon dysfunction.

Joaquim Gonçalves-Neto·S S Witzel·W R Teodoro·A E Carvalho-Júnior·T D Fernandes·H H Yoshinari
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Abstract

OBJECTIVE: To investigate whether tendon degeneration in posterior tibial tendon dysfunction syndrome is associated with changes in extracellular matrix collagen composition. METHODS: Specimens from grossly abnormal tendon regions from 9 patients with posterior tibial tendon dysfunction syndrome were prepared for routine histology. Collagens I, III and V were typed by immunoblotting and quantified by densitometry after SDS-PAGE. Proline and hydroxyproline residues were determined by liquid chromatography. Four other samples from grossly normal homologous tendon regions and one surgical specimen from a healthy patient undergoing arthrodesis of the ankle after an accident were included as control. RESULTS: In the grossly abnormal surgical posterior tibial tendon specimens we observed three types of histopathologic conditions present to varying degrees: increased mucin content, fibroblast hypercellularity and neovascularization. Analysis of degenerate tendons demonstrated a 79.3% increase in total proline and a 32.4% increase in 4-hydroxyproline. In addition, damaged tissue contained a higher proportion of collagen type III (mean increase: 53.6%) associated with a concomitant increase in type V collagen (mean increase: 26.4%). These alterations were accompanied by a reduction in type I collagen (mean decrease: 41.4%). CONCLUSIONS: In posterior tibial tendon dysfunction syndrome, the degenerative process results from marked changes in both structural organization and molecular composition of matrix collagens. The higher proportion of type V and type IlI collagens in degenerated tendons is likely to contribute to a decrease in the mechanical resistance of the tissue.

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AgedChromatography, High Pressure LiquidCollagenElectrophoresis, Polyacrylamide GelExtracellular MatrixFemaleHumansHydroxyprolineMiddle AgedPosterior Tibial Tendon DysfunctionProlineTendinopathyTendonsJournal Article

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Joaquim Gonçalves-Neto, S S Witzel, W R Teodoro, A E Carvalho-Júnior, T D Fernandes, H H Yoshinari. 2002. Changes in collagen matrix composition in human posterior tibial tendon dysfunction.. https://doi.org/10.1016/s1297-319x(02)00369-x

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