High Dose Gamma Irradiated Tibialis Anterior Allograft in Anterior Cruciate Ligament Reconstruction (SS-48)

Abstract

IntroductionAnterior cruciate ligament (ACL) reconstruction with irradiated allografts remains controversial. We prospectively evaluated allograft ACL reconstructions sterilized with high dose gamma radiation.MethodsTwenty-nine (29) consecutive patients underwent arthroscopic ACL reconstruction using highly irradiated tibialis anterior allografts fixated with bioabsorbable interference screws between June 2004 and March 2005. All allografts were obtained from a single tissue bank and sterilized with 5.0 Mrad of irradiation. Follow up exams consisted of International Knee Documentation Committee (IKDC) examination, Tegner scoring and SF-12 survey. Failure was defined as need for revision ACL reconstruction or severely abnormal rating on IKDC. One failure was identified early in the study. Two patients that did not meet inclusion criteria were excluded from analysis.ResultsTwenty-seven (27) patients met inclusion criteria and 22 patients were available for follow up at an average of 36 months (31-48 months), 3 patients were available only for interview. IKDC scoring revealed 15/19 (82%) normal or near normal knees, 3/19 (16%) abnormal knees and 0/19 (0%) severely abnormal knees. Tegner scores dropped from 7.7 preoperatively to 5.7 on follow up,(p<.001). However, there was no statistically significant difference on hop test between the operative and non-operative leg. The average postoperative SF-12 physical composite score of 51.0 and average mental composite score of 51.7 placed patients within mean range for US population.ConclusionA failure rate of 2/22 (9%) observed in this study for allografts sterilized with high dose (5.0 Mrad) irradiation is in contrast to reports of 23% and 33% failure rates recently published. This data suggests that concerns regarding the integrity of grafts sterilized with high dose radiation may be overstated. IntroductionAnterior cruciate ligament (ACL) reconstruction with irradiated allografts remains controversial. We prospectively evaluated allograft ACL reconstructions sterilized with high dose gamma radiation. Anterior cruciate ligament (ACL) reconstruction with irradiated allografts remains controversial. We prospectively evaluated allograft ACL reconstructions sterilized with high dose gamma radiation. MethodsTwenty-nine (29) consecutive patients underwent arthroscopic ACL reconstruction using highly irradiated tibialis anterior allografts fixated with bioabsorbable interference screws between June 2004 and March 2005. All allografts were obtained from a single tissue bank and sterilized with 5.0 Mrad of irradiation. Follow up exams consisted of International Knee Documentation Committee (IKDC) examination, Tegner scoring and SF-12 survey. Failure was defined as need for revision ACL reconstruction or severely abnormal rating on IKDC. One failure was identified early in the study. Two patients that did not meet inclusion criteria were excluded from analysis. Twenty-nine (29) consecutive patients underwent arthroscopic ACL reconstruction using highly irradiated tibialis anterior allografts fixated with bioabsorbable interference screws between June 2004 and March 2005. All allografts were obtained from a single tissue bank and sterilized with 5.0 Mrad of irradiation. Follow up exams consisted of International Knee Documentation Committee (IKDC) examination, Tegner scoring and SF-12 survey. Failure was defined as need for revision ACL reconstruction or severely abnormal rating on IKDC. One failure was identified early in the study. Two patients that did not meet inclusion criteria were excluded from analysis. ResultsTwenty-seven (27) patients met inclusion criteria and 22 patients were available for follow up at an average of 36 months (31-48 months), 3 patients were available only for interview. IKDC scoring revealed 15/19 (82%) normal or near normal knees, 3/19 (16%) abnormal knees and 0/19 (0%) severely abnormal knees. Tegner scores dropped from 7.7 preoperatively to 5.7 on follow up,(p<.001). However, there was no statistically significant difference on hop test between the operative and non-operative leg. The average postoperative SF-12 physical composite score of 51.0 and average mental composite score of 51.7 placed patients within mean range for US population. Twenty-seven (27) patients met inclusion criteria and 22 patients were available for follow up at an average of 36 months (31-48 months), 3 patients were available only for interview. IKDC scoring revealed 15/19 (82%) normal or near normal knees, 3/19 (16%) abnormal knees and 0/19 (0%) severely abnormal knees. Tegner scores dropped from 7.7 preoperatively to 5.7 on follow up,(p<.001). However, there was no statistically significant difference on hop test between the operative and non-operative leg. The average postoperative SF-12 physical composite score of 51.0 and average mental composite score of 51.7 placed patients within mean range for US population. ConclusionA failure rate of 2/22 (9%) observed in this study for allografts sterilized with high dose (5.0 Mrad) irradiation is in contrast to reports of 23% and 33% failure rates recently published. This data suggests that concerns regarding the integrity of grafts sterilized with high dose radiation may be overstated. A failure rate of 2/22 (9%) observed in this study for allografts sterilized with high dose (5.0 Mrad) irradiation is in contrast to reports of 23% and 33% failure rates recently published. This data suggests that concerns regarding the integrity of grafts sterilized with high dose radiation may be overstated.