Treatment of Delbet II/III Pediatric Femoral Neck Fractures With Proximal Femoral Locking Plate Versus Cannulated Screws

Introduction: Complications following operative treatment of pediatric femoral neck fractures include nonunion, coxa vara, and avascular necrosis (AVN). Proximal femoral locking plates (PFLPs) provide a fixed-angle construct that may reduce the rates of coxa vara, but their use in pediatric femoral neck fractures has not been studied. The purpose of this study was to evaluate rates of union, coxa vara, and AVN in traumatic pediatric femoral neck fractures treated with PFLP or cannulated screws (CS). Methods: We retrospectively reviewed all traumatic, non-pathologic Delbet II/III femoral neck fractures in patients below 18 years of age treated with PFLP or CS. All cases had ≥ 6 months of radiographic follow-up to evaluate for osseous union and AVN. Changes in proximal femoral alignment were determined by measuring injured and contralateral femoral neck-shaft angle and articulotrochanteric distance (ATD) between 6 and 12 months postoperatively. Results: Forty-two patients were identified with mean age at surgery of 10.7 ± 2.9 years (range 3.3 to 16.3 years) and mean follow-up of 36 ± 27 months. Sixteen patients (38%) underwent PFLP fixation, whereas 26 patients (62%) underwent CS fixation. When compared with the CS cohort, the PFLP cohort had a greater proportion of males (87.5% vs. 50%, P = 0.02) and Delbet III fractures (68.8% vs. 15.4%, P < 0.001). There was no difference between PFLP and CS cohorts with respect to rates of union (81% vs. 88%, respectively, P = 0.66), AVN (25% vs. 35%, respectively, P = 0.73), or secondary surgery (62% vs 62%, P = 0.95). There was no significant difference in neck-shaft angle between injured and contralateral hips in those patients treated with PFLP (P = 0.93) or CS (P = 0.16). However, the ATD was significantly decreased in hips treated with CS compared with the contralateral hip (18.4 ± 4.6 vs. 23.3 ± 4.2 mm, P = 0.001), with no significant difference in the PFLP group (P = 0.57). Conclusions: This study suggests that the use of a PFLP in Delbet II/III femoral neck fractures does not appear to significantly increase nonunion rates or AVN and maintains anatomic ATD when compared with screw fixation.