Immunohistochemical studies on tenascin in human yellow ligament.

The expression of tenascin in yellow ligaments of 67 males and 26 females was investigated by immunohistochemistry. Positive tenascin staining was observed in matrices around fibroblasts of entheses, particularly in transitional regions between the cartilage and ligament in yellow ligaments, in 38 (57%) of 67 males and in 13 (50%) of 26 females examined. The incidence of positive tenascin staining was 62.5, 60.0 and 50.0% of yellow ligaments obtained from cervical, thoracic and lumbar spines, respectively. There were no significant differences in sex or regions examined. The incidence of positive tenascin staining in yellow ligaments of patients between the ages of 10-29 years, 30-49 years, 50-69 years, 70-80 years was 29, 55, 69 and 40%, respectively. The incidence of positive tenascin staining in yellow ligaments obtained from patients with ossification in posterior longitudinal ligaments and yellow ligaments and from patients with other diseases such as lumbar disc hernition, cervical spondylosis or spinal tumors was 80.0 and 47.9%, respectively. These results show that the appearance of tenascin in ligaments varies with aging and is frequent in spinal diseases with ossification.