Anatomic Anterior Cruciate Ligament Reconstruction in the Skeletally Immature: Is It Possible?

By Daniel Rueff, MD; Robert Royalty, MD; R. Gina Yarnell, CST; Darren L. Johnson, MD

ORTHOPEDICS 2009; 32:839

This article describes a technique that allows for an anatomic anterior cruciate ligament reconstruction that restores normal translational and rotational kinematics to the knee with minimal disruption to the physis.

Reconstruction of the anterior cruciate ligament (ACL) has become one of the most common procedures performed by orthopedic surgeons today with nearly 300,000 performed in the United States each year.1 Intrasubstance ACL ruptures are a common injury in the adult population but traditionally have been thought to be a relatively rare occurrence in skeletally immature patients. However, injuries to the ACL are being increasingly recognized and reported in pediatric and adolescent patients with open growth plates.2-6 This is postulated to be the result of several factors, including the increased participation of young athletes in competitive high level sporting activities and the improved clinical and diagnostic modalities available to evaluate suspected intra-articular injuries in the pediatric and adolescent patient population.7,8

Controversy exists regarding the optimal management of ACL injuries in skeletally immature patients. Nonoperative treatment consisting of physical therapy, bracing, and activity modification has been reported in many studies to lead to an increased incidence of chondral and meniscal injury and continued knee instability.9-13

To allow for a return to sport and prevent further intra-articular damage to the knee, many surgeons advocate early operative treatment of ACL injuries in the skeletally immature.9,11,14-16 However, concern exists regarding physeal injury during surgical reconstruction with complications such as limb-length discrepancy, angular deformities, and premature physeal closure.17-19 Several reports of such growth disturbances following ACL reconstruction have been reported in the literature.20,21

In an effort to prevent injury to the growth plate, extra-articular and modified physeal sparing reconstructions have been developed; however, these are “nonanatomic” techniques and do not replicate the normal ACL anatomy or function.22-25 Long-term follow-up on these nonanatomic techniques is needed to determine how they function over time.

Anatomic ACL reconstruction is thought to decrease anterior tibial translation and increase rotational stability compared to nonanatomic techniques.26-28 Restoration of knee stability and elimination of the pivot shift are essential in young patients due to their increased activity levels and longer postsurgical exposure to sporting activities than their older counterparts. This article presents a surgical technique that provides for anatomical reconstruction of the ACL while minimizing physeal injury via a transepiphyseal femoral tunnel.

Case Report

A 14-year-old female high school/select year-round soccer athlete sustained a noncontact twisting injury to her left knee during practice. Following her injury, she reported continued swelling and instability and was unable to return to competition.

One month post-injury, Lachman’s and pivot shift testing were found to be positive. Knee radiographs revealed open growth plates and magnetic resonance imaging confirmed complete rupture of the ACL. Clinical examination revealed the patient was pre-menarchal, and she desired to return to soccer as soon as possible.

Delaying surgical reconstruction and return to competitive sports was not a viable option for the athlete or her family. As the patient was skeletally immature, she underwent anatomic ACL reconstruction using hamstring autograft with a femoral physeal sparing technique.

Surgical Technique

The patient is placed supine and general anesthesia is administered. The operative leg is placed in an arthroscopic leg holder with the hip flexed to allow for extreme hyperflexion of the knee. After tourniquet insufflation the semitendinosus and gracilis tendons are harvested through a 4-cm longitudinal incision. The tendons are then fashioned into a quadruple bundle graft on the back table and a 15-mm Endobutton CL (Smith & Nephew, Mansfield, Massachusetts) is affixed for femoral sided fixation.

“High and tight” anterolateral and “low and tight” anteromedial portals are created and the knee is surveyed in the usual standard fashion. The ACL tibial remnant is minimally debrided, retaining important tissue for revascularization and reinnervation of the graft. After a limited notchplasty is performed, a far accessory anteromedial portal is created under direct visualization using a spinal needle. This portal allows for anatomic placement and drilling of the femoral tunnel on the lateral femoral wall.

The knee is placed in 90° of flexion and the starting point for the femoral tunnel is marked with an awl through the accessory anteromedial portal. The starting point is positioned directly between the anteromedial and posterolateral bundle attachments on the bifurcate ridge. This mark is placed low on the lateral wall, centered in the area below the lateral intercondylar ridge

A Steinmann pin is placed at the femoral starting point and the knee is then hyperflexed (~140°) to allow for a pin trajectory that remains distal and nearly parallel to the femoral physis A high knee flexion angle is essential to ensure the pin remains below the physis during insertion and eventual tunnel drilling. Proper patient positioning that allows for knee hyperflexion must be confirmed before the start of the surgical procedure. The pin is drilled under fluoroscopic imaging followed by the Endobutton and single fluted femoral tunnel reamers (Figure 3). The tibial footprint is then viewed from the anterolateral portal and the tibial guide placed near the posterior aspect of the footprint. The tibial tunnel is drilled in a more vertical orientation (~65°) than usual, which results in a smaller circular defect in the growth plate compared to the larger elliptical shape produced from drilling the tibial tunnel in a more oblique angle. The graft is then passed and the Endobutton secured against the lateral femoral wall (Figure 4). Fluoroscopic imaging may be used to confirm placement of the Endobutton and femoral tunnel below the physis. The knee is then placed in full extension, and tibial fixation is provided by a screw and washer construct distal to the tibial physis. Alternatively, an anatomic femoral tunnel can be drilled below the femoral physis using an “outside-in” drilling technique with the knee positioned in 90° of knee flexion .

The wounds are closed and a cyrocuff and hinged knee brace are applied. The patient is made weight bearing as tolerated with the brace locked in full extension. The patient is seen within 1 week postoperatively and formal physical therapy including unlimited range of motion, quadriceps strengthening, and patella mobilization are initiated.

Discussion

The participation of children and adolescents with open physis in competitive athletic activity year-round has increased significantly in the past 15 years. Subsequently, so has the incidence of ACL injuries in this patient population. Nonoperative treatment of these injuries leads to further meniscal damage and recurrent instability and hastens early arthrosis of the knee.
Anterior cruciate ligament reconstruction has been shown to reliably restore knee stability while preventing further meniscal and chondral injury in skeletally immature patients in short-term follow-up. However, complications may arise with disruption of the open growth plates during surgical reconstruction.

We have described a surgical technique that allows for an anatomic ACL reconstruction restoring normal translational and rotational kinematics to the knee with minimal disruption to the vulnerable physis.

eferences
Cohen S, Sekiya J. Allograft safety in anterior cruciate ligament reconstruction. Clin Sports Med. 2007; 26(4):597-605.
Bales C, Guettler J, Moorman III C. Anterior cruciate ligament injuries in children with open physes: evolving strategies of treatment. Am J Sports Med. 2004; 32(8):1978-1985.
Kannus P, Järvinen M. Knee ligament injuries in adolescents: eight year follow-up of conservative management. J Bone Joint Surg Br. 1988; 70(5):772-776.
Aichroth P, Patel D, Zorrilla P. The natural history and treatment of rupture of the anterior cruciate ligament in children and adolescents: A prospective review. J Bone Joint Surg Br. 2002; 84(1):38-41.
Johnston DR, Ganley TJ, Flynn JM, Gregg JR. Anterior cruciate ligament injuries in skeletally immature patients. Orthopedics. . 2002; 25(8):864-871.
McCarroll J, Rettig A, Shelbourne K. Anterior cruciate ligament injuries in the young athlete with open physes. Am J Sports Med. 1988; 16(1):44-47.
Shea KG, Pfeiffer R, Wang JH, Curtin M, Apel PJ. Anterior cruciate ligament injury in pediatric and adolescent soccer players: An analysis of insurance data. J Ped Orthop. 2004; 24(6):623-628.
Söderman K, Pietilä T, Alfredson H, Werner S. Anterior cruciate ligament injuries in young females playing soccer at senior levels. Scand J Med Sci Sports. 2002; 12(2):65-68.
Henry J, Chotel F, Chouteau J, Fessy MH, Bérard J, Moyen B. Rupture of the anterior cruciate ligament in children: Early reconstruction with open physes or delayed reconstruction to skeletal maturity? Knee Surg Sports Traumatol Arthrosc. . 2009; 17(7):748-755.
Mizuta H, Kubota K, Shiraishi M, Otsuka Y, Nagamoto N, Takagi K. The conservative treatment of complete tears of the anterior cruciate ligament in skeletally immature patients. J Bone Joint Surg Br. 1995; 77(6):890-894.
Millett P, Willis A, Warren A. Associated injuries in pediatric and adolescent anterior cruciate ligament tears: Does a delay in treatment increase the risk of meniscal tear? Arthroscopy. 2002; 18(9):955-959.
Graf B, Lange R, Fujisaki C, Landry G, Saluja R. Anterior cruciate ligament tears in skeletally immature patients: Meniscal pathology at presentation and after attempted conservative treatment. Arthroscopy. 1992; 8(2):229-233.
McCarroll J, Shelbourne K, Porter D, Rettig A, Murray S. Patellar tendon graft reconstruction for midsubstance anterior cruciate ligament rupture in junior high school athletes: An algorithm for management. Am J Sports Med. 1994; 22(4):478-484.
Mohtadi N, Grant J. Managing anterior cruciate ligament deficiency in the skeletally immature individual: A systematic review of the literature. Clin Sports Med. 2006; 16(6):457-464.
Dorizas J, Stanitski C. Anterior cruciate ligament injury in the skeletally immature. Orthop Clin North Am. 2003; 34(3):355-363.
Janarv PM, Nyström A, Werner S, Hirsch G. Anterior cruciate ligament injuries in skeletally immature patients. J Ped Orthop. 1996; 16(5):673-677.
Koman J, Sanders J. Valgus deformity after reconstruction of the anterior cruciate ligament in a skeletally immature patient. A case report. J Bone Joint Surg Am. 1999; 81(8):711-715.
Ono T, Wada Y, Takahashi K, Minamide M, Moriya H. Tibial deformities and failures of anterior cruciate ligament reconstruction in immature rabbits. J Orthop Sci. 1998; 3(3):150-155.
Higuchi T, Hara K, Tsuji Y, Kubo T. Transepiphyseal reconstruction of the anterior cruciate ligament in skeletally immature athletes: An MRI evaluation for epiphyseal narrowing [published online ahead of print July 18, 2009]. J Pediatr Orthop B.
Kocher M, Saxon H, Hovis W, Hawkins R. Management and complications of anterior cruciate ligament injuries in skeletally immature patients: Survey of the Herodicus Society and The ACL Study Group. J Pediatr Orthop. 2002; 22(4):452-457.
Salzmann G, Spang J, Imhoff A. Double-bundle anterior cruciate ligament reconstruction in a skeletally immature adolescent athlete. Arthroscopy. 2009; 25(3):321-324.
Anderson AF. Transepiphyseal replacement of the anterior cruciate ligament in skeletally immature patients: A preliminary report. J Bone Joint Surg Am. 2003; 85(7):1255-1263.
Odensten M, Gillquist J. Functional anatomy of the anterior cruciate ligament and a rationale for reconstruction. J Bone Joint Surg Am. 1985; 67(2):257-262.
Micheli L, Rask B, Gerberg L. Anterior cruciate ligament reconstruction in patients who are prepubescent. Clin Orthop Relat Res. 1999; (364):40-47.
Parker A, Drez D Jr, Cooper JL. Anterior cruciate ligament injuries in patients with open physes. Am J Sports Med. 1994; 22(1):44-47.
Yagi M, Wong EK, Kanamori A, Debski RE, Fu FH, Woo SL. Biomechanical analysis of an anatomic anterior cruciate ligament reconstruction. Am J Sports Med. 2002; 30(5):660-666.
Gabriel M, Wong E, Woo S, Yagi M, Debski R. Distribution of in situ forces in the anterior cruciate ligament in response to rotatory loads. J Orthop Res. 2004; 22(1):85-89.
Zantop T, Kubo S, Petersen W, Musahl V, Fu F. Current techniques in anatomic anterior cruciate ligament reconstruction. Arthroscopy. 2007; 23(9):938-947.
Authors
Drs Rueff, Royalty, and Johnson and Ms Yarnell are from the Department of Orthopedic Surgery and Sports Medicine, University of Kentucky, Lexington, Kentucky.
Drs Rueff, Royalty, and Johnson and Ms Yarnell have no relevant financial relationships to disclose.
Correspondence should be addressed to: Darren L. Johnson, MD, Department of Sports Medicine, K431 Kentucky Clinic 0284, 740 S Limestone St, Lexington, KY 40536.