Histologic and immunostaining analyses were performed on articular cartilage/subchondral bone biopsy specimens overlying MRI-detected bone bruises in 12 patients with anterior cruciate ligament (ACL) tears. Staining with toluidine blue for proteoglycan revealed loss of staining from the superficial portion of the articular cartilage. Immunostaining for cartilage oligomeric matrix protein (COMP) showed an increased staining in the superficial matrix of the articular cartilage. Using polyclonal antisera against COMP, the authors performed a competitive enzyme-linked immunosorbent assay (ELISA) on the synovial fluid from the injured and uninjured knees. There was an approximately 10-fold higher synovial fluid COMP levels in injured knees. The COMP levels were greater in those patients who had synovial fluid samples harvested closer to the date of initial injury. Western blot analysis of the synovial fluid showed an increased presence of COMP degradation fragments from injured knees. These results are indicative of a significant injury to the articular cartilage, and may represent preclinical posttraumatic osteoarthritic lesions.
|Number of pages||8|
|Journal||Journal of Orthopaedic Research|
|State||Published - 2001|
Bibliographical noteFunding Information:
This study was supported by a research grant from the Orthopaedic Research and Education Foundation (PED), a generous grant from the Anne & Harry J. Reicher Foundation, and grant # RR14099 (CSC) from the National Center for Research Resources of the National Institutes of Health. The authors thank Hermina Borgerink–Tulli for technical assistance.
ASJC Scopus subject areas
- Orthopedics and Sports Medicine