There is also clinical evidence supporting the utility of low-dose irradiated tendons, which also have the advantage of minimizing any risk of disease transmission. Fanelli et al. (1996) compared irradiated BPTB and Achilles tendon allografts versus BPTB autografts for ACL reconstruction in patients who had combined ACL/PCL instability. No irradiation levels were given, so the presumption is of at least a 15-25 kGy dose. Although the sample size was low (20 patients), the prospective study was the largest study to date (1996) that evaluated ACL/PCL instability. This clinical study found equivalent results between irradiated allografts and autograft tendons. In a technique article, Harner and Elkousy, along with lead author Sekiya et al. (2002) , noted they only use patellar tendon allografts that have been irradiated for ACL reconstruction. In further support, Rihn et al. (2006) investigated the irradiation variable for ACL reconstruction in a clinical study involving 102 patients with an average follow-up of 4.2 years. The study found that 2.5 Mrad of gamma irradiation on BPTB allografts, which is effective in eliminating bacteria, does not compromise the clinical effectiveness of the grafts ( Table 2 ). The authors concluded ''[t]hese data suggest that irradiation can be used to sterilize BPTB allograft without adversely affecting clinical outcome.'' Taken together, the above articles suggest that a sterilizing dose of irradiation may not be of clinically significant concern when using allografts for ACL replacement. While three reports in particular have presented higher failure rates for irradiated allografts in ACL reconstructions (Rappe et al. 2007; Sun et al. 2009; Prodromos et al. 2007) , there are significant questions regarding these studies or data analysis.