The related parameters of cartilage and subchondral bone of femoral condyle in bama minipig

Objective To measure the size and thickness of cartilage in femoral condyle and femoral trochlea of mature bama minipig, thus providing a reference for the doable cartilage defect size and depth. Methods The measuring objects were 10 mature female minipigs, scale was used to measure the size of medial and lateral femoral condyle and femoral trochlea, using needle penetration test method for measuring the thickness of cartilage, microCT scanning was applied to measure the bone mineral density, bone volume fraction and trabecular thickness of subchondral bone. Results The thickness of subchondral bone plate and trabeculae were similar in human and minipig. The width of medial femoral condyle was (16.4±1.2) mm, lateral femoral condyle was (15.11±0.95) mm, the width of trochlear medial facet was (11.1±0.6) mm, the lateral facet was (9.0±0.6) mm, cartilage thickness [medial femoral condyle: (1.5±0.2) mm, lateral femoral condyle: (1.55±0.08) mm, medial trochlear facet: (0.8±0.2) mm, lateral trochlear facet: (0.85±0.03) mm], subchondral bone plate thickness [medial condyle: (207±95) μm, trochlea: (95±36) μm], bone mineral density [medial condyle: (0.72±0.12) g/cm3, trochlea: (0.77±0.15) g/cm3], bone volume fraction [medial condyle: (46±7) %, trochlea: (35±11) %], trabecular thickness [medial condyle: (149±15) μm, trochlea: (141±12) μm]; The arrangement and structure of trabeculae in minipig were consistent with that of human. Conclusion Larger cartilage defect with more than 10 mm in diameter can be made in bama minipig due to its advantage of wider medial femoral condyle. Partial full-thickness cartilage defect can also be made owing to its thicker cartilage. Key words: Femoral condyle size; Trochlear groove size; Thickness of cartilage; MicroCT scanning; Osteochondral injury; Minipig