The incidence of anterior cruciate ligament (ACL) injuries in skeletally immature patients increases continuously. This increase is partially because of the developed awareness of the condition and seeking of medical treatment, but also owing to an actual increase of ACL injuries in children, because of greater year-round participation in organized sports at a younger age and early sports specialization. ,
As a consequence, the number of ACL tears in children that require surgical management has increased rapidly, with an average of 58 per 100,000 skeletally immature patients per year being treated for an ACL injury. ,
Despite this increase, controversy still surrounds important aspects of the management of pediatric ACL injuries, such as nonoperative versus operative treatment, the surgical techniques, and the complications after ACL reconstruction (ACLR). Regarding conservative management, recent research offers a significant amount of evidence suggesting a limited role because of the high risk of subsequent cartilage and meniscus injury. , The outcomes of surgical management appear to be promising, especially in a population with high activity levels that corresponds to increased risk of ACL graft tear. Furthermore, the question of potential growth disturbance after ACLR in a patient with open growth plates is critical, but the answer has to be associated with the surgical technique involved.
This chapter will discuss physeal-sparing ACLR with the use of iliotibial (IT) band autograft in skeletally immature patients, focusing on the preoperative, intraoperative, and postoperative complications associated with this technique.
Preoperative Planning and Associated Complications
The goal of this section is to recognize potential challenges in preoperative planning and surgical indications for ACLR with IT band autograft.
In the preoperative planning, it is important to ensure that there are no anatomic variations of the IT band that would preclude its use as a graft. However, the anatomy and the structural properties of the IT band are relatively consistent among different anatomic studies, and only very rare anatomic variations have been described in the literature . Furthermore, the thickness, length, and width of the IT band have also minimal variation, and therefore, harvesting of a graft of adequate length and thickness does not represent a challenge for the average orthopedic surgeon. , ,
In addition, preoperative imaging is important. A hand and wrist x-ray to evaluate skeletal age, as well as Tanner stage evaluation, provides useful information for accurate operative planning. Finally, full-length lower extremity radiographs are critical to evaluate for preexisting leg length discrepancy or angular deformity, and offers a baseline examination for comparison for the postoperative imaging
Surgical Technique and Intraoperative Complications
The patient is positioned supine on the operating table, and general anesthesia and adductor canal regional block are performed. The adductor canal block has been proven equally effective to femoral block in terms of pain control, with a much less risk for quadriceps weakness that can ensure earlier functional recovery postoperatively. A pneumatic tourniquet is applied at the proximal aspect of the thigh. The patient is then examined under anesthesia to confirm ACL deficiency with positive Lachman and pivot shift tests.
The harvesting of the IT band is performed first with a lateral incision of approximately 5 cm made obliquely starting distally at the level of the joint line to the superior border of the IT band proximally and carried down to the subcutaneous tissue until visualization of the IT band. The IT band is prepared for harvesting with subcutaneous tissue elevation along the lateral thigh and in adequate length for graft harvest. The anterior and posterior borders of the IT band are recognized, and two longitudinal incisions are made to the IT band with care so as to maintain some IT band intact, especially at the posterior border, so as to avoid the potential lateral thigh asymmetry at the harvest site as discussed later. A curved meniscotome is then used to continue the incision at the IT band under the skin, and a tendon stripper is used to harvest approximately 15 cm of IT band graft. The distal portion of the IT band is left attached at Gerdy’s tubercle, and dissection is performed distally with extreme care not to violate the joint capsule. If this is violated, fluid can escape from the site, making the later arthroscopic steps challenging. In these cases, capsule repair may be indicated before arthroscopy. The free proximal end of the IT band is whip-stitched to allow graft passage and to ensure the cylindrical shape of the IT band graft.
One of the potential intraoperative complications is associated with the graft harvesting. The surgeon should confirm that there are no adhesions between the IT band and the vastus lateralis muscle. The importance of the clearance of any adhesions ensures harvesting a graft of adequate length (ideally at least 13 cm to safely secure the graft distally). Owing to the superficial nature of the IT band and the familiarity of surgeons with the anatomic structures of the lateral aspect of the knee, this is an extremely rare scenario, but the surgeon should be careful when harvesting the graft. The authors are not aware of any cases in the literature where the graft was too short, but in this unlikely scenario graft suturing at the proximal tibia or allograft augmentation may represent reasonable alternatives.
Subsequently, standard knee arthroscopy is performed through anterolateral and anteromedial portals, with treatment of potential meniscal or chondral injuries at this stage. The torn ACL is debrided, with care to maintain intact or remnant fibers. A full-length clamp is placed into the over-the-top position above a periosteal hinge and under the intermeniscal ligament. The clamp is pushed out around the posterior edge of the lateral femoral condyle and into the incision for the IT band graft harvest. This is then used to retrieve the sutures at the free end of the graft, pulling the IT graft into the joint.
Another potential intraoperative complication of the technique is placement of the graft in a nonanatomic position. There are two important steps to ensure proper graft positioning and thus proper healing of the graft. First, the clamp should be placed under the intermeniscal ligament. Placement of the graft on top of the ligament may prevent healing of the IT band graft at the tibial groove, and this may result in anterior position of the reconstructed ACL and subsequent impingement ( Fig. 13.1A ). Second, the clamp should be placed above the periosteal hinge that is present at the medial edge of the lateral femoral condyle. This periosteal hinge allows the graft to heal at the over-the-top position without risk of graft slippage at a lower nonanatomic position.