The ACL Repair Blog Firsthand accounts of ACL surgery and recovery

This has come up a lot in this blog in the posts and comments.

What is better autograft (hamstring or patella) or allograft (from a cadaver)?

As a biology graduate student I have access to scientific publications and some experience in assessing the published information. There are no official published guidelines for doctors, just scientific articles. Here is what I have found from articles comparing allograft to autograft:

1. There is a lack of randomized trials to compare auto- vs allograft. Randomized studies are very important in science. Think about your doctor. He or she has an opinion on which is better. So the graft you get may be biased by that opinion or, if you decide opposite that doctor’s preference, the surgery itself may be biased. Randomized trials would be if you went to the doctor and picked a surgery (allo- or auto-) out of a hat. These have been done comparing patella tendon versus hamstring but not allo- versus auto-.

2. Failure rate for allograft is significantly higher (9 of 158) than autograft (2 of 167) in observational studies. The review (first citation) recommends autograft, especially for young athletes.

3. Greater chance of deep infection with autograft (2 out of 170) versus allograft (4 out of 628). Significant difference, but all in all, risk was low, maybe too low in this study to tell if there is really a difference.

4. Allografts take longer to revascularize

Additional interesting information I found:

0. There is really no difference in results from patella or hamstring, but patella causes a little more pain. I know this wasn’t auto- vs allo- but still relevant.

1. ACL reconstruction in patients over 50 can be as successful as in younger patients

2. 175,000 ACL reconstructions were performed in 2000

3. Osteoarthritis occurs in 50 % of patients that tear their ACL 10 to 20 years after injury.

4. 60-70% of ACL tears also damage meniscus cartilage.

5. Non-operated ACL tears are more likely to cause further cartilage damage than ACL reconstruction.

6. 15% of patients need additional cartilage or scar tissue surgery after ACL reconstruction (I did for my first knee).

7. Means of graft fixation (how they attach the graft) does not affect outcome

8. Risk of tearing a graft is about 3% after 2 years, the same as your ACL in your other knee (which is what happened to me after 5 years).

I will post later about differences in rehabilitation.

Citations:

Spindler, KP and Wright, RW. 2008. Anterior Cruciate Ligament Tear. New England J of Medicine Katz LM,

Battaglia TC, Patino P, et al. 2008. A Retrospective Comparison of the Incidence of Bacterial Infection Following Anterior Cruciate Ligament Reconstruction With Autograft Versus Allograft. Arthroscopy.

Dahm DL, Wulf CA, Dajani KA, et al. 2008. Reconstruction of the anterior cruciate ligament in patients over 50 years. JOURNAL OF BONE AND JOINT SURGERY-BRITISH VOLUME