Primary- and revision-reconstruction of the anterior cruciate ligament with allografts: A retrospective study including 325 patients

At our institution we have used fresh-frozen allografts for the reconstruction of the anterior and posterior cruciate ligament since 1993. Method: In this retrospective study we evaluated the clinical outcome of 325 fresh-frozen allografts (bone-patellar-tendon-bone allografts and Achilles-bone-tendon allografts) for primary and revision ACL-reconstruction. Patients (average age 38 years) were operated between 5/1993 and 2/1998 and mean follow-up was 38 (range 24 to 71) months. Clinical evaluation consisted of a case history, an examination, IKDC, Cincinnati knee score (CKS), KT-1000 testing and standardized X-rays. Results: Overall subjective rating according to the CKS was more than 82 points for both groups. Objective results according to the IKDC were normal or nearly normal in 75.6% of primary- and 67.0% of revision-ACL reconstructions. The stability measured with the KT-1000 showed an average maximum side to side difference of 2.1 mm for primary ACL reconstruction and 2.3 mm for revisioners. The total failure-rate (= rerupture-rate + laxity-failures) was 13.7% for primary and 15.0% for revision ACL reconstructions. Conclusion: Given the increased failure-rate, autograft tissue remains our graft of first choice for primary ACL-reconstruction. We advise to reserve allografts for revision procedures where suitable autogenous tissues have been previously compromised, where a contraindication for autogenous tissue harvest exists or for multiple ligament surgery. No specific complications were observed with the use of allograft tissue.