An article published in the American Journal of Sports Medicine examines the incidence of anterior cruciate ligament injury in the United States.
The study uses ICD-9 codes in the National Hospital Discharge Survey and the National Survey of Ambulatory Surgery to gather data on ACL tear diagnoses and procedures. The data was gathered from 1994 to 2006. The researchers found:
1. ACL reconstruction grew from 86,687 cases in 1994 to 129,836 cases in 2006. "Research efforts as well as cost-savings measures may be best served by targeting prevention and outcomes measures in these groups," concluded the study authors.
2. For younger patients — younger than 20 years old — and patients who were at least 40 years old, the number of ACL reconstructions increased.
3. Females experienced a significant increased in ACL reconstruction. Among women, ACL reconstruction was up from 10.36 per 100,000 person-years to 18.06 per 100,000 person-years in the 12-year period.
4. Men experienced a slower ACL reconstruction growth rate, although they had more ACL reconstructions overall. Among men, the number of ACL reconstructions grew from 22.58 per 100,000 person-years in 1994 to 25.42 per 100,000 person-years in 2006.
5. In 1994, only 43 percent of ACL reconstructions were performed in an outpatient setting. By 2006, surgeons performed 95 percent of ACL reconstructions in the outpatient setting.
6. Partial meniscectomy and chondroplasty were the most common concomitant procedures. "Surgeons should be aware that concomitant injury is common," concluded the study authors.
Another study published in the American Journal of Sports Medicine examines meniscal repair performed concurrently with anterior cruciate ligament reconstruction for acutely injured knees. The multicenter study examined cases from 2002 to 2004 where patients underwent the procedure and were followed for six months. There were 235 patients included in the study with a six year follow-up.
The researchers found:
7. Repaired menisci involved the peripheral one-third of the meniscus most commonly. The patterns were longitudinal in 84 percent of the cases and displaced bucket-handle in 10 percent of the cases. The average length was 16.5±5.8 mm.
8. There was a 14 percent meniscal repair failure rate. Of the 154 medial meniscal repairs, there were 21 failures; of the 72 lateral meniscal repairs, there were 21 failures; of the nine patients who underwent both repairs, there were two failures.
9. In most cases, medial repairs failed earlier than lateral repairs — failing after 2.1 years while lateral repairs typically failed after around 3.7 years.
10. There were significant outcome score improvements after the six-year follow up for the patients. Additionally, there weren't any differences in the suture number or type between repair failures and successes.
Meniscal reoperation rate was higher in patients who underwent repair as compared with those who did not have identified meniscal injury. "Surgeons may expect good clinical outcomes six years after surgery," concluded the study authors.