Mechanical properties of radiation-sterilised human Bone-Tendon-Bone grafts preserved by different methods

Abstract

Patellar tendon auto- and allo-grafts are commonly used in orthopedic surgery for reconstruction of the anterior cruciate ligaments (ACL). Autografts are mainly used for primary reconstruction, while allografts are useful for revision surgery. To avoid the risk of infectious disease transmission allografts should be radiation-sterilised. As radiation-sterilisation supposedly decreases the mechanical strength of tendon it is important to establish methods of allograft preservation and sterilisation assuring the best quality of grafts and their safety at the same time. Therefore, the purpose of this study was to compare the tensile strength of human patellar tendon (cut out as for ACL reconstruction), preserved by various methods (deep fresh freezing, glycerolisation, lyophilisation) and subsequently radiation-sterilised with doses of 0, 25, 50 or 100 kGy. Bone-Tendon-Bone grafts (BTB) were prepared from cadaveric human patella tendons with both patellar and tibial attachments. BTB grafts were preserved by deep freezing, glycerolisation or lyophilisation and were subsequently radiation-sterilised with doses of 0 (control), 25, 50 or 100 kGy. All samples were subjected to mechanical failure tensile tests with the use of Instron system in order to estimate their mechanical properties. All lyophilised grafts were rehydrated before performing of those tests. Obtained mechanical tests results of examined grafts suggest that deep-frozen irradiated grafts retain their initial mechanical properties to an extent which does not exclude their clinical application.

Revision of anterior cruciate ligament reconstruction with patellar tendon allograft and autograft: 2- and 5-year results

“…A possible reason for this Wnding lies in the use of high-dose gamma irradiation for sterilization [41]. Kaminski et al [23] carried out mechanical tests at baseline and concluded that adequate results can be achieved using deep-frozen transplants with additional irradiation. They did not take into account the ligamentization process.…”

A Preliminary Clinical Comparison of the Use of Fascia Lata Allograft and Autogenous Connective Tissue Graft in Multiple Gingival Recession Coverage Based on the Tunnel Technique

“…The local immune response, although visible, has no effect on the incorporation of the allogeneic graft. A commonly applied conservation method is irradiation of the fascia in a physiological salt solution with 33 kGy [21]. Based on nine randomized clinical studies featuring 208 subjects and 858 gingival recessions Graziani et al [22] discussed the effectiveness of periodontal plastic procedures in covering multiple gingival recession defects.…”

Radiation sterilization of tissue allografts: A review

“…Electron beam is a high energy electron treatment which is currently used for sterilization of medical devices and in radiation therapy. A number of tissue banks have used accelerated electron beam for sterilization of human tissues [25,41,42] . As compared to gamma radiation, accelerated electron beam has lower penetration into the material.…”