title: Morphologic and histologic comparison between the patella and hamstring tendons grafts: a descriptive and anatomic study.
abstract: OBJECTIVE
  Morphologic and histologic comparison of patella and hamstring tendon grafts.
  
  
  METHODS
  Hamstring tendons (semitendinosus and gracilis) and patellar tendons were taken from 20 cadaveric knees and were investigated by using light and electron microscopy, immunohistochemistry, and morphometry. The thickness of collagen fibrils, fibril/interstitum ratio, density of blood vessels, density of fibroblasts, and distribution of the collagen fibrils were analyzed.
  
  
  RESULTS
  The semitendinosus and gracilis tendons provide 20% and 30% more fibril/interstitum ratio compared with the patella tendon (P = .0056 and .0028). Also, the density of fibroblasts was 50% and 35% more (P = .0061 and .0050). No differences regarding the thickness of the collagen fibrils, density of blood vessels, and distribution of the fibrils were found.
  
  
  CONCLUSIONS
  Both semitendinous and gracilis tendons provide significantly more density of collagen fibrils as well as density of fibroblasts in comparison with patellar tendons. These findings provide a potential advantage of the hamstrings group on better remodelling and regeneration of the tissue.
  
  
  CONCLUSIONS
  These grafts have been used as autografts for anterior cruciate ligament reconstruction. Despite the interest on these tendons, their microscopic structure has not been sufficiently investigated yet.
authors.affiliation: ATOS Clinic, Centre for Knee and Foot Surgery, Heidelberg, Germany. phadjicostas@yahoo.com
authors.forename: Panayiotis T
authors.initials: PT
authors.lastname: Hadjicostas
authors.forename: Panayotis N
authors.initials: PN
authors.lastname: Soucacos
authors.forename: Hans H
authors.initials: HH
authors.lastname: Paessler
authors.forename: Nadezda
authors.initials: N
authors.lastname: Koleganova
authors.forename: Irina
authors.initials: I
authors.lastname: Berger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; 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 / Q000637:transplantation; D013710:Tendons / Q000033:anatomy & histology* / Q000637:transplantation*; D019737:Transplants
chemical_list: D003094:Collagen