Table of Contents
- Autograft vs. Allograft
- Study Parameters and Patient Criteria
- Unexpected Findings
- Challenges in Comparing Study Results
- Recommendations for Future Research
Introduction: The Lack of Comparative Studies on ACL Reconstruction
Can you believe it? Out of 5,000 studies published since 1990, only one compared the results of autograft to allograft reconstruction surgery for an anterior cruciate ligament (ACL) tear. That’s what orthopedic surgeons report after conducting an extensive systematic review of studies on ACL reconstruction surgery.
Autograft vs. Allograft: A Crucial Decision in ACL Surgery
When a patient tears or ruptures the ACL ligament inside the knee, surgery is often needed to restore the stability that the anterior cruciate ligament (ACL) provides the knee. The best way to do this is to take tissue (usually a tendon) from some place else around the patient’s own knee (that’s an autograft) or from a donor bank (allograft) and stitch it in place.
Study Parameters and Patient Criteria
The question these surgeons asked was, which one is better: autograft or allograft? They used measures of joint stability (e.g., the Lachman test, pivot-shift test, and KT-1000 arthrometer) as one way to look at results. They also looked at knee function and failure rates as measures of outcome.
Unexpected Findings: Autografts vs. Allografts
Before starting their search, they identified a specific subset of patients to study. Only studies using live humans were included. The patients in these studies had only one knee involved and only the ACL ligament was damaged. Many times, an acute traumatic injury powerful enough to rupture the ACL will also tear other soft tissue structures in the knee. None of the patients had a previous history of other surgeries on the involved knee.
Challenges in Comparing Study Results
With more than a quarter of a million ACL reconstruction surgeries performed in the United States each year, and 80 per cent of those using autografts, you would think the question of allograft versus autograft would be settled. In fact, the authors thought they would find no differences in results or outcomes between the two graft choices.
Recommendations for Future Research
The final conclusion from this meta-analysis was that researchers may need to direct future studies toward comparing autograft to allograft ACL reconstructive surgeries. This is important before continuing to choose autografts over allografts. Autografts have the disadvantage of causing problems at the donor site such as infection, persistent pain, and possible deformity. Allografts eliminate those problems but have their own issues with potential tissue rejection by the patient.
The authors suggest it would be helpful if comparative studies select patients carefully so that other factors don’t cloud the results. Outcome measures using valid tests like the Tegner activity score, Cincinnati knee score, Lysholm score, and International Knee Documentation Committee (IKDC) score should be used in all studies to allow for more accurate comparisons of results.
Lisa M. Tibor, MD, et al. Clinical Outcomes After Anterior Cruciate Ligament Reconstruction: A Meta-Analysis of Autograft Versus Allograft Tissue. In Sports Health. January/February 2010. Vol. 2. No. 1. Pp. 56-72.