title: Bone marrow stimulation of the medial femoral condyle produces inferior cartilage and bone repair compared to the trochlea in a rabbit surgical model.
abstract: The influence of the location of cartilage lesions on cartilage repair outcome is incompletely understood. This study compared cartilage and bone repair in medial femoral condylar (MFC) versus femoral trochlear (TR) defects 3 months after bone marrow stimulation in mature rabbits. Intact femurs from adult rabbits served as controls. Results from quantitative histomorphometry and histological scoring showed that bone marrow stimulation produced inferior soft tissue repair in MFC versus TR defects, as indicated by significantly lower % Fill (p = 0.03), a significant increase in collagen type I immunostaining (p < 0.00001) and lower O'Driscoll scores (p < 0.05). 3D micro-CT analysis showed that repaired TR defects regained normal un-operated values of bone volume fraction, trabecular thickness, and trabecular number, whereas in MFC defects the repaired bone architecture appeared immature and less dense compared to intact un-operated MFC controls (p < 0.0001). Severe medial meniscal damage was found in 28% of operated animals and was strongly correlated with (i) low cartilage defect fill, (ii) incomplete bone repair in MFC, and (iii) with a more posterior defect placement in the weight-bearing region. We conclude that the location of cartilage lesions influences cartilage repair, with better outcome in TR versus MFC defects in rabbits. Meniscal degeneration is associated with cartilage damage.
authors.affiliation: Department of Chemical Engineering and Institute of Biomedical Engineering, École Polytechnique de Montréal, PO Box 6079, Station Centre-ville, Montréal, Quebec, Canada H3C 3A7.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Chen
authors.forename: Anik
authors.initials: A
authors.lastname: Chevrier
authors.forename: Caroline D
authors.initials: CD
authors.lastname: Hoemann
authors.forename: Jun
authors.initials: J
authors.lastname: Sun
authors.forename: Genevieve
authors.initials: G
authors.lastname: Picard
authors.forename: Michael D
authors.initials: MD
authors.lastname: Buschmann
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000502:physiology*; D002358:Cartilage, Articular / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005269:Femur / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D008592:Menisci, Tibial / Q000473:pathology; D008953:Models, Anatomic; D023421:Models, Animal; D011817:Rabbits; D014945:Wound Healing; D055114:X-Ray Microtomography
keywords: bone marrow stimulation; cartilage repair; medial femoral condyle; meniscus degeneration; trochlea