Anterior Cruciate Ligament Reconstruction With Iliotibial Band Autograft in Skeletally Immature Prepubescent Children: A Physeal-Sparing Technique

Abstract

Background:

As there has been an increasing incidence of anterior cruciate ligament (ACL) tears in children and adolescents in the past few decades, nonoperative management is seen to result in less favorable clinical outcomes, resulting in meniscal and cartilage damage, and arthritic changes. Despite the risk of iatrogenic physeal injuries with operative approach, several reconstruction options, such as physeal-sparing techniques for skeletally immature patients, are described to restore joint stability.

Indications:

We bring a combined extra-articular and intra-articular ACL reconstruction technique using autogenous iliotibial band (ITB), which is indicated for prepubescent patients (Tanner stages 1 or 2) with open physes, significant growth potential (≤11 years for girls and ≤12 years for boys) and smaller knees, where an all-epiphyseal ACL reconstruction would lack epiphyseal space

Technique Description:

The technique consists of a modified MacIntosh intra-articular and extra-articular ITB reconstruction, described by Micheli and further characterized by Kocher. The central portion of the ITB is harvested proximally (at least 15 cm) and left attached to Gerdy's tubercle distally. The harvested graft is brought from over-the-top posteriorly and passed under the intermeniscal ligament anteriorly through an epiphyseal groove on the tibia.

Results:

The outcomes shown for the Kocher ITB ACL reconstruction technique are favorable at a mean follow-up of 5.3 years: from 44 patients, 41 returned to sports involving cutting or pivoting, and the revision rate was low at 4.5%.

Discussion/Conclusion:

The awareness of physeal injury related to the operative treatment of ACL tears in the pediatric population has resulted in several physeal-sparing and physeal-respecting techniques of reconstruction. Some of these have shown to reduce the risk of physeal damage, maintaining stability and providing excellent functional outcomes, with low revision rates in long-term follow-up and minimal risk of growth disturbance.

Patient Consent Disclosure Statement:

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

There has been an increasing incidence of anterior cruciate ligament (ACL) tears in children and adolescents in the past few decades.^8,2 Greater awareness, associated with more accurate diagnosis and higher participation of children in competitive sports, contributes to a trend toward higher number of ACL tears in pediatric and adolescent patients, ² with databases showing rates of ACL reconstructions on this population rise from nearly threefold to 5.7-fold. ¹³

Nonoperative management is seen to result in less favorable clinical outcomes regarding participation on sports at the preinjury level of activity, ⁹ with knee instability contributing to further meniscal and cartilage damage, and arthritic changes. ⁴

The risk of iatrogenic physeal injuries with operative approach ² must be considered, since the growth plates around the knee are responsible for 65% to 70% of the longitudinal growth of the lower extremity. ¹⁰ Several reconstruction options can be considered depending on the skeletal and physiological age ¹ —which is based on Tanner staging system—such as physeal-sparing techniques for skeletally immature patients—and are described to restore joint stability. ⁵

These ACL reconstruction options can be divided as physeal-sparing (extra-physeal and all-epiphyseal reconstructions)—techniques that are typically used for skeletally immature prepubescent children ³ —partial transphyseal, and also transphyseal. None of these techniques shows universal superiority.

The case that follows shows an 8-year-old male patient who suffered a knee sprain during a judo practice, followed by knee instability and persistent pain. The clinical examination showed a neutral knee alignment, limping gait, and Tanner 1 stage. Knee examination revealed Anterior Drawer, Lachman, and pivot-shift tests 3/3+, without peripheral ligament injuries on varus or valgus stress. Knee radiography shows open physis and no signs of fractures. Magnetic resonance imaging (MRI) depicts an ACL complete tear.

We present a physeal-sparing technique, for prepubescent children (Tanner stages 1 or 2) with open physes, significant growth potential (≤11 years for girls and ≤12 years for boys), and smaller knees. This technique is a modified MacIntosh intra-articular and extra-articular iliotibial band (ITB) reconstruction, described by Micheli and further characterized by Kocher. On this technique, the central portion of the ITB is harvested proximally using a stripper (at least 15 cm length, as shown) and is left attached to Gerdy's tubercle distally.

During the arthroscopic procedure, a longitudinal lateral meniscal tear was diagnosed and treated accordingly with 3 all-inside stitches. Carefully, the position of the distal femur and proximal tibial physis is checked with fluoroscopy. After a minimal notchplasty, with the help of a passing suture and a grasper inserted through the anteromedial knee portal, the loose end of the harvested graft is brought out from over-the-top posteriorly into the joint. Using the same grasper, the harvested graft is passed under the intermeniscal ligament to exit the joint anteriorly through an epiphyseal groove on the tibia. Both steps can be quite challenging and require a skilled surgeon to perform the graft passage and avoid iatrogenic physeal injuries.

The free end of the ITB graft is brought out to a tibial incision made over the medial aspect of the proximal tibia, of about 3 to 4 cm, medial to the tibial tubercle and distal to the tibial physis, at the pes anserinus bursa level. Dissection is carried down to the tibial periosteum, which will aid fixation afterward.

Maintaining the knee on 90° of flexion, and tibia on neutral rotation, the graft is fixed proximally with mattress sutures to the lateral intermuscular septum, securing the over-the-top position. After bringing the knee into full extension, periosteum flaps are developed distally to the proximal tibial physis in a longitudinal fashion. The graft is sutured to these periosteal flaps under tension. Knee range of motion and Lachman test are performed to assess stability. This is followed by skin incisions closure, sterile draping, and the use of a hinged knee brace, restricting flexion from 0° to 90° initially.

Postoperative rehabilitation is initiated with 6 weeks of touch-down weightbearing and range of motion limited to 90° of flexion for the first 2 weeks in a hinged knee brace, followed by progression to full range of motion. During the first 12 weeks, rehabilitation includes progression to full weightbearing, complete range of motion, proprioception, patellar mobilization, and closed-chain strengthening exercises. After this initial phase, the patient starts straight-line jogging, plyometric, and sport-specific exercises. Return to sports begins at 6 months for nonpivoting and 9 to 12 months for pivoting sports. Maintaining hinged knee brace should be considered for 1 to 2 years postoperatively for high-risk activities.

Technical pearls to ACL reconstruction in prepubescent children include preoperatively assessing emotional maturity to the postoperative activity limitations and intense rehabilitation regimen; transepicondylar distance can help the surgeon calculate the ITB length required; during surgery, the free end of the graft should be folded, wrapped in a moist sponge, and tucked under the skin to prevent desiccation during the rest of the arthroscopic procedure; an inferolateral sling of ACL stump should be left to decrease the likelihood of graft subluxating into the lateral tibiofemoral compartment; tibial fixation should be performed medial to the tibial tubercle apophysis, avoiding iatrogenic physeal injury; postoperatively, a slower return to sports is protective against subsequent ACL injury.

Technical pitfalls regarding ITB fascia harvesting suggest that insufficient length can result in a graft too short to effectively secure to the tibia. It is recommended to attempt to harvest a 15-cm-long graft. Also, care should be taken while dissecting around the posterolateral aspect of the femoral condyle or overly vigorous posterior notchplasty, which could cause injury to the perichondral ring and possible deformity associated.

The awareness of physeal injury related to the operative treatment of ACL tears in the pediatric population has resulted in several physeal-sparing and physeal-respecting techniques of reconstruction.^6,11 Although some authors criticize these techniques because of its usual “nonanatomic” configuration, biomechanical studies have shown otherwise, with a good restoration of kinematic constraint.^7,12

This ITB physeal-sparing technique described by Micheli and Kocher can reduce the risk of physeal damage, maintaining stability and providing excellent functional outcomes, with low revision rates: at a mean follow-up of 5.3 years, from 44 patients, 41 returned to sports involving cutting or pivoting, and the revision rate was at 4.5%. The mean functional scores at the final follow-up were 96.7 ± 6.0 points on the International Knee Documentation Committee (IKDC) subjective knee assessment and Lysholm Knee Scoring Scale (LKSS) of 95.7 ± 6.7 points out of 100. No clinical or radiographic growth disturbances or angular deformities occurred during this series follow-up.

To summarize, physeal-sparing and physeal-respecting ACL reconstruction techniques reduce the risk of physeal damage, with ITB autograft ACL reconstruction maintaining stability and providing excellent functional outcomes, with low revision rates in long-term follow-up and minimal risk of growth disturbance.