| Purpose To approach the content and distribution change of collagen types I and III in anterior cruciate ligament(ACL) and it's histological features with knee osteoarthritis(OA). Methods 29 ACLs harvested from 27 cases of knee OA who were undertaken total knee arthroplasty(TKA) were selected as OA group, 5 normal ACLs harvested from traumatic amputation were selected as control group. All specimens were stained by 1% Sirius Red F3B in Saturated Carbazotic Acid to observe the distribution feature and analyze the content of collagen types I and III in ACL. Meanwhile, use HE stain to observe histological changes. Results By Sirius Red F3B in Saturated Carbazotic Acid stain, we observed that, under polarized light, slices of normal ACLs were mainly constructed by collagen types I and III, the collagen fibers were lined up in order just like striped muscle. Among them, collagen types I was thicker and distributed at most part of ACLs; collagen types III was less and only distributed inner of bundles of the ligaments. In the slices of OA group, the alignment of collagen fibers is disordered and the content of collagen types III increased obviously. Under HE stain, OA slices become loose, and had different types of fibrous connective tissue degeneration, such as inhomogeneous fibrocyte increase or decrease; mucinous degeneration; Chondroid metaplasia; cystis degeneration or glassy degeneration. Conclusion Sirius Red F3B in Saturated Carbazotic Acid stain is a proper stain method for observation the distribution feature and calculating the content of collagen types I/III in ACLs. The content and distribution of collagen types I/III changed when Knee OAcombined with ACL degeneration. The degeneration of ACL has association with OA severity. |
