Meniscal ossification in spontaneous osteoarthritis in the guinea-pig

Objective: The purpose of this study was to evaluate the ossification state of the meniscus in the guinea-pig stifle joint using micro-computerized to mography. Design: Hind limbs from six (N=12) and 24 (N=11) month-old male Hartley gui nea-pigs were removed and the joints were imaged using high resolution micr o-computerized tomography. The ossified volume of the medial and lateral me nisci from both groups of animals was quantified. Results: Ossification of both the medial and lateral menisci of the both th e 6- and 24-month-old animals was observed. In both age goups, the ossified region of the medial meniscus was significantly larger than the lateral me niscus. In addition, there is a significant increase in ossified volume of the medial meniscus between 6 and 24 months of age. Conclusions: There is a significant amount of ossification of the menisci i n the male Hartley guinea-pig, with the medial compartment showing more bon e than the lateral. In addition, as the animals age, there is an increase i n ossification within the medial compartment. Bone remodeling and cartilage degeneration is evident in the medial compartment within these animals as they age. It is possible that the increased ossification of the medial meni scus could alter the joint biomechanics and, in part, stimulate this medial compartment joint destruction. (C) 2000 OsteoArthritis Research Society In ternational.