The influence of donor and recipient characteristics on allograft tendons: a systematic review

Tendon allograft has been an important alternative graft option aside from autograft. The outcome of reconstruction surgery is determined by donor and recipient related factors. The purpose of this article was to identified all studies reporting donor and recipient characteristics, including the age and gender of donors, along with the age, gender, activity level and smoking status of recipients, that affect the biomechanical properties and post-transplantation outcomes of allograft tendons. The systematic study search was based on MEDLINE via PubMed, Embase and the Cochrane Library databases. The reference lists of the included studies were used for hand searching (snowballing). The searching process was performed by two independent investigators, using search MESH term: "tendon", "allograft", and "person". Studies evaluating the influence of donor and recipient biological characteristics on the mechanical property and transplantation outcome of allograft were included. A total of 12 studies were selected for qualitative synthesis, including 6 studies evaluated the influence of donor characteristics, including age and gender, on the mechanical strength of tendon allograft. 6 studies assessed the influence of recipient characteristics, including age, gender, smoking status, and activity level, on the clinical outcome. As a conclusion, tendon allografts from donor younger than 40 years old were expected to have a higher mechanical property. Young patients or patients with a high level of activity were not recommended to receive allograft tendon when autograft is optional. There is no strong evidence supporting that neither donor or recipient gender affects the tendon allograft transplantation outcomes. Smoking history could increase the risk of complications.