Identifying Risk Zones for Neurovascular Injury in Pediatric All-Inside Arthroscopic Lateral Meniscal Repair.

Background: All-inside techniques for meniscal repairs offer comparable outcomes and healing rates with reduced operative time and fewer incisions; however, iatrogenic neurovascular injuries during arthroscopic meniscal repairs are a significant concern.

Purpose: To identify the zones of risk and incidence of injury concerning the common peroneal nerve (CPN) and popliteal artery in relation to the popliteal tendon (PT) from the anterolateral (AL) and anteromedial (AM) portals during a simulated all-inside technique in the pediatric population.

Study Design: Descriptive laboratory study.

Methods: Using axial knee magnetic resonance imaging scans of 124 patients, the all-inside technique was simulated by drawing direct lines from the AM and AL portals to the medial and lateral borders of the PT. If the line came into contact with the CPN, a risk of projected iatrogenic CPN injury was found. Measurements were then recorded to assess and define "risk zones." A similar simulation was performed in relation to the popliteal artery to assess distance to projected iatrogenic injury.

Results: The risk of CPN injury was significantly higher when using the AL portal (45%) compared with the AM portal (19%) when simulating repair at the lateral edge of the PT ( < .001). Similarly, there was a significantly higher risk of peroneal nerve injury when using the AM portal (29%) compared with the AL portal (8.9%) when simulating repair from the medial edge of the PT ( < .001). The risk of injury when repairing the body of the lateral meniscus through the AM portal extended 2.20 ± 0.98 mm laterally from the lateral edge of the PT and 3.14 ± 1.92 mm medially from the medial edge of the PT. The risk of injury when repairing the body of the lateral meniscus through the AL portal extended 2.58 ± 1.31 mm lateral to the lateral edge of the PT and 2.02 ± 1.61 mm medial to the medial edge of the PT.

Conclusion: The authors found that the AM portal was safer for repairing the body of the lateral meniscus while simulating repair at the lateral edge of the PT, while the AL portal was safer for repairing the lateral meniscus while simulating repair from the medial edge of the PT.

Clinical Relevance: By understanding these risk profiles, surgeons can adopt safer approaches for meniscal repairs in pediatric patients, thereby minimizing the likelihood of injuring sensitive neurovascular structures.