title: Pulsed carbon dioxide laser for cartilage vaporization and subchondral bone perforation in horses. Part II: Morphologic and histochemical reactions.
abstract: A pulsed carbon dioxide laser was used to vaporize articular cartilage in four horses, and perforate the cartilage and subchondral bone in four horses. Both intercarpal joints were examined arthroscopically and either a 1 cm cartilage crater or a series of holes was created in the third carpal bone of one joint. The contralateral carpus served as a control. After euthanasia at week 8, the treated and control joints were examined for gross changes, and samples of cartilage and subchondral bone, synovial membrane, and peripheral lymph nodes were examined histologically. Depletion of cartilage matrix glycosaminoglycan was assessed by safranin-O histochemical staining of the laser site and adjacent cartilage. Cartilage removal by laser vaporization resulted in rapid regrowth, with fibrous and fibrovascular tissue and occasional regions of fibrocartilage at week 8. The subchondral bone, synovial membrane, and draining lymph nodes appeared essentially unaffected by the laser cartilage vaporization procedure. Conversely, carbon dioxide laser drilling of subchondral bone resulted in poor penetration, extensive areas of thermal necrosis of bone, and significant secondary damage to the apposing articular surface of the radial carpal bone.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853.
authors.forename: A J
authors.initials: AJ
authors.lastname: Nixon
authors.forename: L P
authors.initials: LP
authors.lastname: Krook
authors.forename: J E
authors.initials: JE
authors.lastname: Roth
authors.forename: J M
authors.initials: JM
authors.lastname: King
mesh_terms: D000818:Animals; D001182:Arthroscopy / Q000662:veterinary; D001842:Bone and Bones / Q000737:chemistry / Q000473:pathology / Q000601:surgery*; D002350:Carpus, Animal / Q000737:chemistry / Q000473:pathology / Q000601:surgery*; D002358:Cartilage, Articular / Q000737:chemistry / Q000473:pathology / Q000601:surgery*; D006025:Glycosaminoglycans / Q000032:analysis; D006651:Histocytochemistry; D006736:Horses / Q000601:surgery*; D053685:Laser Therapy / Q000662:veterinary*; D008198:Lymph Nodes / Q000737:chemistry / Q000473:pathology; D010619:Phenazines; D013194:Staining and Labeling; D013582:Synovial Fluid / Q000737:chemistry; D013583:Synovial Membrane / Q000737:chemistry / Q000473:pathology
chemical_list: D006025:Glycosaminoglycans; D010619:Phenazines; C009195:safranine T