The purpose of this study was to document in detail the severity and extent of articular cartilage lesions and the location and type of meniscus lesions that were associated with anterior cruciate ligament injuries. This documentation was done at the time of anterior cruciate ligament surgery by one reviewer-surgeon with the purpose of determining the association between the patient's sex, age, and length of surgical delay as well as the frequency and location of these meniscus and articular cartilage lesions.
The study group was large, consisting of 1104 patients who had undergone anterior cruciate ligament surgery between 1988 and 2002. The results revealed that patients with a surgical delay of less than three months were less likely to have a medial meniscus injury. Also, patients who were twenty-five years of age or older were more likely to have multiple cartilaginous lesions. Patients with a surgical delay that exceeded one year were more likely to have cartilaginous lesions with a greater proportion of deeper lesions. Patients who were more than thirty-five years of age had more associated meniscal injuries and more severe articular cartilage lesions. The authors concluded that increased age, male sex, and longer surgical delay were associated with a higher frequency and severity of injuries of the meniscus and/or articular cartilage after an anterior cruciate ligament tear.
The new information from this paper is the detailing of the severity and extent of these lesions associated with anterior cruciate ligament rupture. A previous study1 by O'Connor et al. on 1375 consecutive patients with anterior cruciate ligament injuries concluded that men consistently had a higher rate of meniscal injuries and that meniscal injuries increased at a higher rate over time among women. Also, the risk of meniscal injuries increased when anterior cruciate ligament reconstruction was performed more than six months after injury, and articular cartilage lesions increased when anterior cruciate ligament reconstruction was performed one year later or more. O'Connor's study, however, did not detail the depth of lesions of the articular cartilage, the extent of these lesions, or whether they were single or multiple. Keene et al.2 reviewed 176 consecutive patients undergoing anterior cruciate ligament reconstruction and found that there was a higher prevalence of meniscal injury in chronic anterior cruciate ligament repairs after twelve months, with the meniscal tears becoming more complex and less amenable to suture repair. Hart et al.3 studied anterior cruciate ligament reconstructed knees with computed tomography to determine the long-term risk of arthritic changes. Ten years postoperatively, patients with a partial meniscectomy done at the time of the anterior cruciate ligament reconstruction had a significant increase in degenerative changes (p < 0.05).
This current study is very important in that it points out that the longer the delay from anterior cruciate ligament injury to surgical repair, the more damage will occur to the articular and meniscal regions of the knee joint. With this information, the clinician is able to advise his or her patients more accurately, pointing to the evidence from this large and comprehensive study that the knee is at increased risk for future injury. Meniscal and articular lesions may occur more frequently if the initial problem of anterior cruciate ligament laxity is not addressed appropriately.
One weakness of the study is that it does not mention the degree of anterior cruciate ligament laxity, as measured with use of the Lachman test, the anterior drawer test, or the pivot shift test, that was present at the time of the index surgery. Would more lesions have been seen if increased laxity had been present?
Also not mentioned in the study was the amount of activity between the time of injury and the time of the index surgery. Did these patients return to vigorous sporting activities, such as skiing and snowboarding, after they were injured and prior to the anterior cruciate ligament reconstruction? Another study4 evaluated anterior cruciate ligament-deficient individuals as far as their ability to cope or not cope with sporting activities by whether they could hop and do certain other tests efficiently. That study concluded that the amount of laxity was not correlated with functional outcome measurements or episodes of instability. It seems logical that increased activities after an anterior cruciate ligament injury, particularly in those who are coping and not having symptoms, would result in more articular and meniscal injuries on the basis of the abnormal biomechanics of the knee. Therefore, patients should be advised to either markedly decrease certain sporting activities if no anterior cruciate ligament reconstruction surgery is to be done or proceed to stabilization of anterior cruciate ligament function to prevent further injuries, address concomitant injuries, and possibly prevent degenerative changes in the knee.
In summary, in this well-documented study, femoral articular cartilage injuries were identified in 43% of the patients at the time of anterior cruciate ligament surgery. This information will help surgeons in planning preoperatively about whether to treat these lesions with grafting, microfracture, or some other method to prevent further deterioration of the articular surface. This study has shown that increased patient age results in an increased number of lesions, but it does not make reference to the amount of sporting activity that is being done, which, depending on the amount, could be causing more damage.
*The author did not receive any outside funding or grants in support of his research for or preparation of this work. Neither he nor a member of his immediate family received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity.
1. O'Connor DP, Laughlin MS, Woods GW. Factors related to additional knee injuries after anterior cruciate ligament injury. Arthroscopy. 2005;21:431-8.
2. Keene GC, Bickerstaff D, Rae PJ, Paterson RS. The natural history of meniscal tears in anterior cruciate ligament insufficiency. Am J Sports Med. 1993;21:672-9.
3. Hart AJ, Buscombe J, Malone A, Dowd GS. Assessment of osteoarthritis after reconstruction of the anterior cruciate ligament: a study using single-photon emission computed tomography at ten years. J Bone Joint Surg Br. 2005;87:1483-7.
4. Eastlack ME, Axe MJ, Snyder-Mackler L. Laxity, instability, and functional outcome after ACL injury: copers versus noncopers. Med Sci Sports Exerc. 1999;31:210-5.