Development and assessment of biologically compatible anterior cruciate ligament using braided ultra-high molecular weight polyethylene.

In this study, a ultra-high molecular weight polyethylene (UHMWPE) braided structure was surface modified with low temperature plasma and was coated with cationized gelatin and hyaluronic acid to improve its biocompatibility for the reconstruction of an anterior cruciate ligament (ACL). The ligament was studied for its various mechanical properties. Surface modifications were studied through FESEM. Biological compatibility of the ligament was assessed in accordance to ISO 10993 standard. Tensile strength of the UHMWPE reconstructed ligament ranges between 2628 and 5937 N; maximum tensile strength was attained in 1600 denier 2/2 pattern of triple braided structure along with higher strain at failure of 36.1%. In 1600 denier 2/2 pattern of triple braid structure, the linear stiffness was found to be high at 375 N/mm. Among the developed materials, four braided structures namely as 800 denier 2/2 pattern of double braids and triple braids, 1600 denier 1/1 pattern of double braid and 2/2 pattern of triple braid were found to be mechanically suitable. Specifically, the 1600 denier 2/2 pattern of triple braid having higher mechanical properties was selected for coating. The results of in-vitro cytotoxicity and genotoxicity confirmed the extract of ACL to non-toxic and non-mutant. Furthermore, in-vivo analysis of the extract and the coated ACL graft proved the ligament to be non-irritant, non-sensitizer and also found to promote new tissue formation around the graft. Based on the results, the CG and HA coated ACL graft were concluded to be biocompatible and having considerable potential as an alternate for autograft/allograft.