Complications in Pediatric Anterior Cruciate Ligament Surgery: All-Epiphyseal Technique

Growth Arrest

In a series of 12 patients (mean age 13.3 years) who underwent transepiphyseal ACLR using hamstring autograft, Anderson et al. reported no significant growth disturbances. More recently, Nawabi et al. performed a physeal-specific magnetic resonance imaging (MRI) technique to quantify the zone of physeal injury following all-epiphyseal reconstruction techniques. It was concluded that all-epiphyseal reconstruction results in minimal growth plate compromise does did not supersede the published thresholds for growth arrest.

Although the all-epiphyseal techniques were developed to provide femoral and tibial reconstruction tunnels or sockets that avoid crossing the physes, the risk of iatrogenic physeal injuries still exists. Measures to decrease this likelihood of growth disturbance include the use of soft tissue grafts in place of bone tendon grafts. Numerous authors have described success of the all-epiphyseal reconstruction with soft tissues grafts. ^{, ,} Cordasco, Mayer, and Green described a case series of 23 patients treated with the all-inside all-epiphyseal reconstruction, in which a small physeal violation (<5% surface area of the physis) by either the femoral or tibial tunnel was seen in 12 patients. Although no clinically significant growth disturbances were noted, six patients had a limb-length discrepancy of more than 5 mm that did not require treatment. The largest retrospective series to date of all-epiphyseal ACLR outcomes by Cruz et al. noted growth arrest in a single patient out of the 103 that were followed for an average of 21 months postoperatively. As with many complications associated with all-epiphyseal ACLR, larger studies with long-term follow-up are necessary to establish the true incidence of growth disturbances.

Angular Deformity

Angular deformity is a rare complication of all-inside all-epiphyseal reconstruction relative to transphyseal reconstruction techniques. Koch et al. described a case series of 12 patients who underwent all-epiphyseal reconstruction in which one patient developed a significant limb-length discrepancy with 20 mm of overgrowth and varus malalignment after a second reconstruction. Although angular deformity could be the result of all-epiphyseal reconstruction, mechanical axes data was only available postoperatively, and physiological limb axes differences could not be excluded in this patient. We discuss a rare case of angular deformity secondary to all epiphyseal ACLR in the case presentation later.

Limb-Length Discrepancy

Limb overgrowth after all-epiphyseal ACLR has been observed in numerous independent case series of all-epiphyseal reconstruction. ^{, ,} Theoretical explanations of this phenomena include a possible mechanical stimulation of the physeal growth plate zone via adjacent surgery in addition to an increase in epiphyseal blood flow. Out of 23 cases of all-inside all-epiphyseal ACLR, Cordasco, Mayer, and Green found overgrowth of more than 5 mm and less than 20 mm in six patients (26%). Similarly, Koch et al. described a series of 12 patients where six (50%) patients demonstrated overgrowth, two of which presented with a limb-length discrepancy greater than 20 mm. Preoperative and frequent postoperative radiographs are thus recommended to monitor growth disturbance to initiate timely clinical management or surgical management if necessary.