Anterior cruciate ligament injuries in the skeletally immature patient.

Lo IK, Bell DM, Fowler PJ. Instr Course Lect 1998;47:351-9

Anterior cruciate ligament injury in the skeletally immature is becoming increasingly recognized and reported. History taking and physical examination based on the principles of ACL injuries in adults, with adjuncts such as arthroscopy and MRI, are effective in diagnosing ACL injury in the young patient. Evaluation of the young patient’s true level of skeletal immaturity by comparison with family growth history, examination for signs of sexual maturity, and radiographic evaluation is critical. The risk of physeal damage with surgical treatment is related to the immaturity of the distal femoral and proximal tibial physes. The functional results of nonsurgical treatment of ACL injury, either as an attempt at definitive treatment or as a temporizing plan until skeletal maturity occurs, are poor and the risks of reinjury and further meniscal and cartilage damage are significant. Surgical treatment for primary repair or extra-articular reconstruction alone has not proven to be efficacious. In the adolescent patient who is approaching skeletal maturity, risk of physeal injury is low and intra-articular reconstruction can be performed as in the adult patient. Results with respect to decreased laxity and return to athletic activities mirror those described in adults. In patients with significant growth remaining, however, surgical treatment carries much higher risks of physeal damage and subsequent deformity. Yet, as noted above, intra-articular reconstruction in truly skeletally immature patients using a soft-tissue graft through a transphyseal tibial tunnel of moderate or small diameter and the over-the-top position on the femur has not been shown to cause early physeal closure, limb-length discrepancy, or angular deformity. In humans, the maximum diameter of graft tunnel that will not cause physeal closure has not been determined Animal studies have shown that the tibial physis can be very sensitive to drilling. Therefore it is wise to use moderate tunnel diameters. Bone-patellar tendon-bone grafts have been used with success in patients closer to skeletal maturity. Their use has not been reported in the very skeletally immature knee and cannot be recommended because of the presumed high risk of physeal closure with a bone plug traversing the physis. It is hoped that improved understanding of the ACL injury in the skeletally immature patient will provide treatment options that will restore enduring knee function and prevent early arthrosis.

Anterior cruciate injuries in the skeletally immature athlete: a review of treatment outcomes.

Fehnel DJ, Johnson R. Sports Med 2000 Jan;29(1):51-63

The documentation of anterior cruciate ligament (ACL) injuries in the skeletally immature athlete has significantly increased over the past decade, primarily due to increased awareness of these injuries within this younger athletic population. The evaluation of these injuries are similar to that in the adult population. Diagnostic studies such as plain radiographs, as well as magnetic resonance imaging, can delineate the location of the ACL failure. Physical presentation most commonly includes an acute haemarthrosis and ligamentous insufficiency. Several studies have demonstrated that the diagnostic reliability of the physical examination is poor in children, especially in patients less than 12 years old. The site of ACL failure in this adolescent population is most commonly at the tibial insertion. We recommend arthroscopic or arthroscopically assisted open reduction and internal fixation with nonabsorbable sutures for all displaced tibial eminence fractures. Mid-substance ACL failures also occur in this athletic age group. The association of meniscal injuries with these ACL failures appears to be greater than 50%. Historically, poor subjective and objective outcomes have been associated with primary and extra-articular repairs. Intra-articular reconstruction is the gold standard. The issue of placing the graft across open physeal plates is under investigation. Recent animal studies as well as human clinical series have demonstrated safety in placing soft tissue, i.e. hamstring grafts, across open growth plates without subsequent angular or leg length discrepancy. Historically, non-operatively treated ACL failures are associated with poor functional outcomes as well as a high incidence of meniscal re-injury. If the treatment of an adolescent athlete with an ACL failure is to be rehabilitation until skeletal maturity, close follow-up is essential to detect functional instability, which may prompt earlier surgical reconstruction.

ACL injuries in the skeletally immature patient.

Hawkins CA, Rosen JE. Bull Hosp Jt Dis 2000;59(4):227-31

Anterior cruciate ligament injuries are becoming increasingly prevalent in a younger, more athletic population. These injuries require aggressive management given the poor natural history with regard to progressive meniscal damage and advanced degenerative changes. In general, strict nonoperative management has been associated with failure in the individual committed to return to an active lifestyle. As a result a general algorithm can be expressed as follows: 1. Activity limitations and bracing are initially used for the asymptomatic skeletally immature patient with a complete ACL tear. 2. If the patient remains asymptomatic, formal reconstruction can be delayed until skeletal maturity. 3. For the symptomatic patient a precise delineation of their physical development or skeletal age is important. 4. In patients who have reached Tanner IV secondary sexual development or a skeletal age of 13-14 (F/M), a traditional transphyseal reconstruction with hamstring autografts is appropriate. 5. In the skeletally immature patient who has significant skeletal development ahead of them, the judicious use of physeal sparing procedures is an option for the surgeon comfortable with these techniques. In this case the goal is temporization until formal transphyseal reconstruction can be performed after the peak of skeletal growth.

Diagnosis of acute rupture of the anterior cruciate ligament of the knee by sonography.

Skovgaard Larsen LP, Rasmussen OS. Eur J Ultrasound 2000 Dec 1;12(2):163-167.

The accuracy of sonography in the diagnosis of acute rupture of the anterior cruciate ligament (ACL) was tested. Sixty-two patients with a recent traumatic haemarthrosis were examinated. A haematoma at the origin of the ACL in the femoral intercondylar notch was interpreted as evidence of ligament injury. The standard of reference was arthroscopy or clinical follow-up. The sonographic findings were confirmed in 59 of 62 cases. The sensitivity was 88%, the specificity 98%, and the positive and negative predictive values 93 and 96%.