Study: Allograft Fails More Readily in Young Athletes

In young athletic patients, anterior cruciate ligament (ACL) reconstruction performed with allograft has a higher failure rate than reconstruction with autograft, according to long-term study results.

“ACL reconstruction at our institution using posterior tibialis allograft had a significantly higher failure rate than an autologous hamstring in exactly similar fixation and rehab protocol ─ three times higher as shown here. However, all [patients] with intact grafts had good clinical outcomes,” said Craig R. Bottoni, M.D.

In the prospective study, Bottoni and colleagues randomized 99 patients, for a total of 100 symptomatic ACL deficient knees, to receive either hamstring autograft or tibialis posterior tendon allograft. The cohort included 87 men, and 95 patients were active duty military. Both groups had a mean age of 29 years and there was no difference in their concomitant pathology or demographics.

The researchers used fresh-frozen aseptically harvested, non-terminally irradiated allografts obtained from a single tissue bank. Graft fixation was identical for all knees and both groups followed the identical blinded postoperative rehabilitation protocol. The researchers performed preoperative and postoperative assessments of the patient’s knees by exam, telephone and Internet-based questionnaires. The primary outcome measures used were graft integrity, subjective knee stability and functional status. Minimum follow-up was 10 years.

For the 96 patients who were able to be contacted at follow-up, Bottoni and colleagues found failure rates of 26.5 percent for allograft and 8.5 percent for autograft. All other patients had intact grafts and there was no difference in clinical outcomes.