Many people with knee injuries want to wait before having surgery to repair a torn anterior cruciate ligament (ACL). And there is evidence to support this decision for some patients. But in many cases, the ACL isn't the only injury present. Often, the meniscus and joint cartilage are torn, too. How does delaying surgery affect the repair rate for these associated injuries?
In this study, a large amount of data from the Kaiser Permanente Anterior Cruciate Ligament Reconstruction Registry was used to answer three questions:
- What's the relationship between time-to-surgery, age, and sex (male versus female) on the injury pattern (e.g., just meniscus, just cartilage, both meniscus and cartilage).
- What is the effect of time-to-surgery, age, and sex on repair rates for ACL plus a torn meniscus?
- How do the results of this study compare with other (previously reported) studies?
Kaiser Permanente is a large health care facility located across the United States in 35 medical centers and 431 medical offices. They serve more than 8.8 million members. The special registry for ACL patients used for this study included patients from three different locations under the care of 20 surgeons.
The information for each patient treated surgically to reconstruct a ruptured ACL was placed into the computer database. Information included patient demographics (age, occupation, sex, date-of-injury, date-of-surgery). The record for each patient also included type of soft tissue injury and results of surgical repair (repair rates).
By running various computer statistical programs, the authors were able to analyze and evaluate a total of 1252 patients. They found that delaying surgery (12 months or more) was linked to a greater risk of medial meniscus and joint cartilage injury. The delay was also likely to result in a reduced repair rate.
That answers the first question (relationship between time-to-surgery and the effect of patient variables on injury pattern). And it also answers the third question (how do these results compare with what other studies have reported). The results of this Kaiser study are very similar to other smaller studies that showed a delay in time-to-surgery was linked with poorer outcomes.
This Kaiser study took a look at more than just time-to-surgery by comparing age and sex as additional possible risk factors for greater injury and decreased repair rates. What else did they find here? Younger patients were more likely to just suffer an ACL tear without other soft tissue injuries. Females made up more of the younger age group than males. Men tend to participate in active sports longer so injure themselves across a broader range of ages.
Being male and older age were also risk factors for meniscal and cartilage injuries. Men were at greater risk of lateral meniscus injury and combined injuries (e.g., ACL tear plus meniscus AND cartilage damage). Time-to-surgery and age didn't seem to be linked with lateral meniscal injuries.
What are the implications of these findings? Surgeons may want to advise patients to consider surgery sooner than later. A simple ACL tear can become a full rupture and lead to additional soft tissue injuries of meniscus and cartilage. Chronic knee instability may be avoided with early repair and restoration of the anterior cruciate ligament.
For those individuals who wish to wait (delay surgery), activity modification is important. They should be advised to avoid pivoting or twisting type actions of the knee (especially with the foot planted on the ground). Ligament repair should be done before returning to these kinds of activities, which increase the risk of further damaging the meniscus and cartilage.
Reference: Ankur M. Chhadia, MD, et al. Are Meniscus and Cartilage Injuries Related to Time to Anterior Cruciate Ligament Reconstruction? In The American Journal of Sports Medicine. September 2011. Vol. 39. No. 9. Pp. 1894-1899.