Time Heals Everything--Except, Apparently, the ACL

Time heals everything. Or does it? A group of orthopedists in Australia set out to discover the relationship between the passage of time after a knee injury and the extent of knee damage. The researchers looked specifically at meniscus and cartilage damage in patients after an anterior cruciate ligament (ACL) injury.

The ACL connects the thigh bone with the tibia in the lower leg. The ACL plays a key role in stabilizing the knee. Injury to the ACL has been tied to damage of the cartilage surfaces and menisci of the knee. When the ACL is injured, the knee may become unstable, putting more strain and wear on these other knee structures.

Using an arthroscope, researchers looked inside the knees of 130 patients with known ACL damage. (All subjects were scheduled for surgery to repair their damaged knee ligament.) The subjects ranged from one month to a couple of years past the initial knee injury.
Researchers found that the more time that passed since the initial injury, the greater the damage to the cartilage and meniscus. Most patients (72%) showed meniscal damage or loss, with an average of three inches of cartilage damage.

To keep these other knee structures from being damaged, the authors conclude that ACL injuries should be surgically repaired sooner rather than later. The researchers caution that these findings may not apply to all ACL injuries, since many don't require surgery.

Damage to the cartilage and meniscus may also have something to do with how badly the knee was initially injured. And it is possible some of the subjects already had damage to these other knee structures before they injured their ACL. Still, this study shows that the passage of time can do more harm than good.



References: George A.C. Murrell, MBBS, DPhil, et al. The Effects of Time Course After Anterior Cruciate Ligament Injury in Correlation With Meniscal and Cartilage Loss. In The American Journal of Sports Medicine. January/February 2001. Vol. 29. No.1. Pp. 9-14.