Modified Macintosh Extra-Articular Anterior Cruciate Ligament Reconstruction in a 6-Year-Old Patient

Abstract

Background:

Anterior cruciate ligament (ACL) injury in children is an increasingly common occurrence. Historically, nonsurgical treatment has been the main treatment option; however, the indication for surgical reconstruction is increasing, as the histological characteristics of the immature skeleton are better known.

Indications:

The extra-articular surgical technique for ACL reconstruction is a good option for Tanner I patients, aged up to 8 years, with knee instability and recurrent pain. Its advantage in skeletally immature patients is due to the fact that it avoids the bone growth plates.

Technique Description:

After skin incision and subcutaneous dissection, we isolated the iliotibial band and released the proximal portion of the band. We proceeded with the tubularization of the graft, suturing its edges, and with the aid of radioscopy we marked the top of the lateral femoral condyle. Thus, we transported the graft, in an over-the-top position, to the intercondylar portion of the femur. Femoral fixation is performed by placing the graft close to the lateral femoral condyle. For fixation on the tibia, a second incision is made, preserving the physis, and the graft is fixed to the tibia using an absorbable Swivelock anchor.

Results:

Six months after the surgery, when his physical rehabilitation was completed, the patient was asymptomatic and able to perform his daily activities, and also returned to sports. Clinical evaluation showed a knee with almost the same functional parameters as the uninjured one. Furthermore, radiographic studies showed no bone abnormalities and magnetic resonance image showed a newly reconstructed ligament with good positioning.

Discussion/Conclusion:

According to the literature, surgical treatment seems to be better than conservative treatment in skeletally immature patients. However, there is a continuous discussion about the most appropriate surgical technique. The decision is relative to many specific characteristics for these patients: age, bone age, graft choice, sports modality, and surgeon expertise. In this case, we decide to do an ACL extra-articular reconstruction technique with the iliotibial band over the top in the femoral condyle and fixed in the anterior cortical bone of the tibia.

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

My name is Diego Astur and I will talk about a modified MacIntosh extra-articular anterior cruciate ligament (ACL) in a 6-year-old patient.

This is the case of a 6-year-old boy who suffered a torsional trauma to the left knee after jumping and presented with instability and lateral pain of the same knee.^1,2

During physical examination, the patient presented positive maneuvers for ACL injury (Lachman test, anterior drawer test, and pivot-shift +), normal range of motion and gait, and good alignment.

The patient had open physes on radiographics, with no other abnormalities and good alignment on the lower limb panoramic view. He was classified as a Tanner I. The sagittal and coronal view from the magnetic resonance imaging (MRI) scan confirmed the ACL injury and no other injuries were seen.

The younger the patient is, the better the chance to treat them with no surgery, but according to the most recent studies, we know that those patients respond better with surgical treatment than with conservative treatment.^3-6 However, we don't exactly know the best technique to use in these patients. That is the reason why we always say we have to know everything about the patient. Tanner stage is one of the characteristics we can use to better understand and decide what kind of treatment we will do.^7-10

A few years ago, we published a case report about a 4-year-old patient with an ACL injury that we decided to treat surgically. After almost 10 years, he seems very good. In those Tanner I stage patients, the physes are not completely developed, making the transepiphyseal technique not always possible. Most of the time, we don't have enough bone to make the tunnels. Even though the extra-articular technique does not provide an anatomic ACL reconstruction, in this type of case patients tend to present excellent results.

Usually we have 3 types of surgical techniques to treat these pediatric patients: Extra-articular surgeries for the younger patients who do not present enough epiphyses for bone tunnels, epiphyseal reconstruction for patients with enough epiphysis to do a safe bone tunnel, and transphyseal done in the same manner as for an adult patient.

Surgery begins with the arthroscopy of the knee. We initiate with the patient in supine position on the operating table. After making the anterolateral and anteromedial video arthroscopic portals, we begin with the visualization of all the knee compartments to see all of the most important structures of the knee and to confirm that the ACL is totally torn.

A lateral skin approach is done from the Gerdy tubercle to the lateral femoral cortical. With this 10 to 12 cm exposure, we intend to see the iliotibial tract. With the iliotibial band completely exposed, we mark the central bundle with 1 cm of width and 12 cm of length. We cut along the marks, preserving the distal insertion of the iliotibial band.

Then, we begin with the tubularization of the iliotibial tract. We suture the edges together with Monocryl wire. With the help of scopes or radiographs, we can locate the top of the lateral femoral condyle. With a small dissection and arthrotomy from outside to inside with a shaver device, we can define the way to pass the graft.

A needle can help to find the best position in the tibia below the intermeniscal ligament. Then, using guide wires, we can pass a wire from the lateral side to the intercondylar space.

A second approach is done 3 to 4 cm distal to the physis in the anteromedial side of the knee. Then we can pass the wire, which is under the intermeniscal ligament, through this incision. Using the guidewire, we can pass the graft over the top on the femorolateral side to the intraarticular knee. Finally, we can confirm the position of the graft from the arthroscopic view.

After tensioning, we suture the graft on the lateral femoral condyle first. And then we fix the graft to the tibia using an absorbable Swivelock anchor. The last step is to test the stability of the graft after the surgery.

Six months after surgery, when his physical rehabilitation was completed, the patient was asymptomatic and able to perform his daily activities, and he was also back to sports. Eighteen months after surgery, the MRI scan shows a healthy and well-positioned graft.