Return to full duty after anterior cruciate ligament reconstruction: is the second time more difficult?

Anterior cruciate ligament (ACL) injuries occur repeatedly in Special Operations Forces (SOF). In this study, we sought to determine whether military patients requiring a second (i.e., revision) ACL reconstruction in the same knee had a lower rate of return to full duty and greater chance of medical discharge versus those undergoing first-time (i.e., primary) ACL knee surgery. A single- institution, retrospective analysis of surgical records and medical board data of active duty members during a 4-year period identified 19 revision and 169 primary ACL cases, respectively. Measured end points were rate of return to full duty in each group and odds ratio (with 95% confidence interval) for medical discharge. Our results showed that 17 (90%) of 19 revision ACL patients returned to full duty at a mean of 7.5 ? 2.3 months. Two patients did not return to full duty and were medically discharged at 12 and 13 months, respectively. Meanwhile, 155 (92%) of 169 primary ACL patients returned to full duty (mean 7.3 ? 2.3 months), and 14 patients were medically discharged (mean 8.5 ? 2.8 months). Patients in the revision group were only 1.30 times (odds ratio) (95% confidence interval, 0.2726?6.2229) more likely to be medically discharged than patients in the primary group. Overall, the majority of revision ACL surgeries were successful. The period of limited duty was slightly longer after revision ACL surgery. Return to full duty was seen at a similar rate as primary ACL surgery, and the odds of medical discharge were statistically similar. The results are useful in counseling SOF members who might need to undergo revision ACL surgery.