Comparative analysis of the morphologic structure of quadriceps and patellar tendon: a descriptive laboratory study.
OBJECTIVE
The difference in ultimate strength between the quadriceps and patellar tendon could be reflected by different morphologic features.


METHODS
Standardized samples of quadriceps and patellar tendons were harvested from 20 cadavers and were investigated via light and electron microscopy, immunohistochemistry, and morphometry. The thickness of collagen fibrils, fibril-interstitium ratio, density of blood vessels, density of fibroblasts, and distribution of collagen fibrils were analyzed.


RESULTS
In comparison with the patellar tendon, the quadriceps tendon showed a significantly higher fibril-interstitium ratio (P = .0004) and a higher fibroblast density (P = .0011). No differences regarding the thickness of collagen fibrils, density of blood vessels, and distribution of fibrils were found.


CONCLUSIONS
The quadriceps tendon graft can provide approximately 20% more collagen than the patellar tendon graft with the same thickness. This fact can play an important role in the better ultimate strength of the quadriceps tendon.


CONCLUSIONS
The detailed anatomic description of the quadriceps tendon and patellar tendon explains the difference in their ultimate strength.
Hadjicostas
Panayiotis T
PT
Department of Pathology, University of Heidelberg, Germany. phadjicostas@yahoo.com
Soucacos
Panayotis N
PN
Berger
Irina
I
Koleganova
Nadezda
N
Paessler
Hans H
HH
D000328:Adult; D000368:Aged; D002102:Cadaver; D003094:Collagen / Q000648:ultrastructure; D005260:Female; D005347:Fibroblasts / Q000648:ultrastructure; D006801:Humans; D007717:Knee / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D017847:Patellar Ligament / Q000033:anatomy & histology; D052097:Quadriceps Muscle; D013710:Tendons / Q000033:anatomy & histology*
D003094:Collagen