Biological response of intramedullary bone to poly‐ L ‐lactic acid

作者：J. Suganuma, Harold Alexander · 发表于：Journal of Applied Biomaterials · 年份：1993 · DOI：10.1002/jab.770040103 · 被引用次数：213 · 研究领域：biodegradable polymer synthesis and properties、Bone Tissue Engineering Materials、Orthopaedic implants and arthroplasty

Abstract This study focuses on examining the biological response of intramedullary bone to poly‐L‐lactic acid (PLLA), particularly during the PLLA degradation phase. To study the influence of spherical crystals (spherulites) of PLLA on intramedullary bone response, two different types of PLLA coupon, with and without spherulites but with the same molecular weight, were used. Chambers containing PLLA coupons were implanted into the right femur of eight dogs, four with and four without spherulites; chambers containing stainless steel (SS) coupons (as a control) were implanted in the left femurs of all eight. Two dogs, one with and one without spherulites, were sacrificed at 3, 6, 12, and 24 weeks postoperatively. Histomorphometric evaluation and histophathological assessment were used to compare the response to PLLA and SS. Scanning electron micrographs showed that there were minimal changes in the surface of PLLA coupons at 3 and 6 weeks. But at 12 and 24 weeks, there were many cracks and holes on the surfaces of the coupons, and some parts of the surface were scaling off. The cross‐sectional area of PLLA coupons showed no change at 3 and 6 weeks, but started to decrease by 12 weeks. The amount of ingrown bone between PLLA coupons was significantly greater than that between SS coupons at 3 and 6 weeks, but had decreased dramatically by 12 weeks. Extensive bone resorption around PLLA coupons occurred by 12 weeks accompanied by infiltration of inflammatory cells. An abundance of...