Functional Ultra-High Molecular Weight Polyethylene Composites for Ligament Reconstructions and Their Targeted Applications in the Restoration of the Anterior Cruciate Ligament

Abstract

The selection of biomaterials as biomedical implants is a significant challenge. Ultra-high molecular weight polyethylene (UHMWPE) and composites of such kind have been extensively used in medical implants, notably in the bearings of the hip, knee, and other joint prostheses, owing to its biocompatibility and high wear resistance. For the Anterior Cruciate Ligament (ACL) graft, synthetic UHMWPE is an ideal candidate due to its biocompatibility and extremely high tensile strength. However, significant problems are observed in UHMWPE based implants, such as wear debris and oxidative degradation. To resolve the issue of wear and to enhance the life of UHMWPE as an implant, in recent years, this field has witnessed numerous innovative methodologies such as biofunctionalization or high temperature melting of UHMWPE to enhance its toughness and strength. The surface functionalization/modification/treatment of UHMWPE is very challenging as it requires optimizing many variables, such as surface tension and wettability, active functional groups on the surface, irradiation, and protein immobilization to successfully improve the mechanical properties of UHMWPE and reduce or eliminate the wear or osteolysis of the UHMWPE implant. Despite these difficulties, several surface roughening, functionalization, and irradiation processing technologies have been developed and applied in the recent past. The basic research and direct industrial applications of such material improvement technology are very significant, as evidenced by the significant number of published papers and patents. However, the available literature on research methodology and techniques related to material property enhancement and protection from wear of UHMWPE is disseminated, and there is a lack of a comprehensive source for the research community to access information on the subject matter. Here we provide an overview of recent developments and core challenges in the surface modification/functionalization/irradiation of UHMWPE and apply these findings to the case study of UHMWPE for ACL repair.

Biomaterials in Orthopedic Devices: Current Issues and Future Perspectives

“…Polyethylene is used in total hip and knee arthroplasty, insertion of the tibia, or as a spacer in disc replacement [64,67]. The major benefits of PE use are: low resistance to friction, resistance to abrasion or to impact, and good biocompatibility.…”

A Comprehensive Review of Ultrahigh Molecular Weight Polyethylene Fibers for Applications Based on Their Different Preparation Techniques

“…Many different routes, such as improving cross-linking [6,7], improving crystallinity percentage [8,9], irradiation [10], surface modification through plasma treatment [11,12], the introduction of effective textures [13,14], and reinforcement with different fillers [15][16][17][18], have been used to enhance the properties of bulk UHMWPE. Several review papers have been published, summarizing the recent developments in enhancing the mechanical, tribological, and thermal characteristics of UHMWPE for diverse uses [19][20][21][22]. However, there is still a need to consolidate this progress and provide a comprehensive overview of the research conducted on UHMWPE and its specific uses.…”