CT angiography-based analysis of femoral artery anatomy for medial distal femoral approaches in children.

Abstract

Medial distal femoral approaches are rarely required in children but may be necessary in selected tumour, deformity, or trauma cases. In such instances, understanding the spatial relationship between the femoral artery and medial bony landmarks is essential to avoid vascular injury. This study aimed to define the vascular-safe zone for medial distal femoral exposure in skeletally immature patients using CT angiography. This retrospective study analysed 49 paediatric lower extremity CTA scans to evaluate the course of the femoral artery in relation to key medial bony landmarks: the femoral adductor tubercle and medial knee joint line. Measurements were performed at three femoral sagittal levels (anterior cortex, midsagittal plane, posterior cortex) and adjusted to femur length. Additional measurements included the artery's proximity to the medial femoral cortex and the location of the descending genicular artery (DGA). The femoral artery followed an oblique course in the thigh, crossing from anterior-superior to posterior-inferior. When the femoral adductor tubercle used as the reference point, the artery crossed the anterior, midsagittal, and posterior cortices at approximately 60 %, 49 %, and 39 % of the femoral length, respectively. At the posterior level, the artery was significantly closer to the bone (18.17 ± 8.48 mm, p = 0.0105). The DGA originated at 19.5 % of femur length proximal to the adductor tubercle, and the femoral artery crossed behind the posterior intermuscular septum at 16.8 %. While absolute distances increased with age, femur-length-adjusted values remained consistent across age groups. Medial distal femoral approach may be necessary in selected paediatric tumour, deformity, or trauma cases. This study defines the vascular-safe zone in relation to femur length, providing clinically relevant guidance for safe surgical exposure. III, diagnostic.