A review of materials for managing bone loss in revision total knee arthroplasty

In 2014-2015, 61,421 total knee arthroplasties (TKAs) were performed in Canada; an increase of about 20% over 2000-2001. Revision total knee arthroplasties (rTKAs) accounted for 6.8% of TKAs performed between 2014 and 2015, and this is estimated to grow another 12% by 2025. rTKAs are typically more complicated than primary TKAs due to the significant loss of femoral and tibial bone stock. The escalating demand and limitations associated with total knee arthroplasty and their revision drives the development of novel treatments. A variety of materials have been utilized to facilitate regeneration of healthy bone around the site of a knee arthroplasty. The selection of these materials is based on the bone defect size and includes bone grafts, graft substitutes and cements. However, all these materials have certain disadvantages such as blood loss, disease transmission (bone grafts), inflammatory response, insufficient mechanical properties (bone graft substitutes) thermal necrosis and stress shielding (bone cement). Recently, the use of metal augments for large bone defects has attracted attention, however they can undergo fretting, corrosion, and stress shielding. All things considered, this review indicates the necessity of developing augments that have structural integrities and biodegradation rates similar to that of human bone. Therefore, the future of bone loss management may lie in fabricating novel bioactive glass augments as they can promote bone healing and implant stability and can degrade with time.