Chondrocyte viability in press-fit cryopreserved osteochondral allografts.
The viability of chondrocytes in press-fit glycerol-preserved osteochondral allografts was compared to that in fresh autografts, after transplantation into load-bearing and non-load-bearing sites in mature sheep stifle joints. We used macroscopic grading, tonometer pen indentation testing, histology, sulfate uptake and viability as determined by confocal-microscopy to assess cartilage condition. Despite there being no statistical differences between macroscopic appearance and tonometer testing of all grafts, confocal microscopy and histology demonstrated a positive effect of load-bearing placement on cryopreserved osteochondral allografts. Allografts transplanted into load-bearing sites demonstrated superior confocal microscopy-measured chondrocyte viability (77%+/-17%SD) than those transplanted into non-load-bearing sites (25%+/-2%). Load-bearing effect was not seen in autografts (78%+/-15%), and was comparable in adjacent cartilage (83%+/-9%). Similarly, load-bearing allografts demonstrated histological scoring closer to that of autografts and adjacent cartilage, all of which fared significantly better than non-load-bearing allografts. Load-bearing allografts had a greater amount of fibrocartilage than autografts or adjacent cartilage but less fibrocartilage than non-load-bearing allografts. Both autografts and allografts had non-significant increases in metabolism compared to adjacent cartilage as measured by sulfate-uptake. Load-bearing placement improved chondrocyte viability of glycerol cryopreserved osteochondral allograft following a press-fit implantation.
Gole
Madhura D
MD
Orthopaedics Section, Veterans Administration--Western New York Health Care System, 124 Sherman Hall, Buffalo, NY 14215, USA.
Poulsen
Dan
D
Marzo
John M
JM
Ko
Seung-Hee
SH
Ziv
Israel
I
D000818:Animals; D016025:Bone Transplantation / Q000379:methods*; D002358:Cartilage, Articular / Q000293:injuries / Q000473:pathology / Q000637:transplantation*; D002470:Cell Survival; D019902:Chondrocytes / Q000473:pathology / Q000502:physiology / Q000637:transplantation*; D015925:Cryopreservation; D004195:Disease Models, Animal; D018613:Microscopy, Confocal; D012756:Sheep; D013264:Stifle / Q000503:physiopathology / Q000601:surgery*; D014184:Transplantation, Homologous; D016474:Weight-Bearing