Case Report: Proximal femoral valgus osteotomy and dynamic hip screw fixation for post-traumatic coxa vara secondary to femoral neck or intertrochanteric fracture nonunion or malunion: a retrospective case series.

BACKGROUND: Post-traumatic coxa vara following femoral neck or intertrochanteric fracture nonunion or malunion remains a difficult problem in young and middle-aged patients, in whom salvage total hip arthroplasty carries excess complication risk. Proximal femoral valgus osteotomy is a joint-preserving alternative, but evidence supporting fixation with a dynamic hip screw (DHS) is limited, and is largely confined to younger cohorts. CASE SUMMARY: We report a single-center, retrospective, consecutive case series of twelve patients (seven men, five women; mean age 52.2 ± 20.0 years, range 20-73) treated between January 2020 and December 2024. Etiologies included failed internal fixation of intertrochanteric fracture (n = 6), malunion of intertrochanteric fracture (n = 3), failed internal fixation of femoral neck fracture (n = 2), and malunion of femoral neck fracture (n = 1). All patients underwent proximal femoral valgus osteotomy with DHS-based fixation, supplemented as required by cannulated screws or a reconstruction plate. Outcomes were assessed at a minimum follow-up of 12 months. OUTCOMES: Bony union was achieved in all twelve patients at a mean of 19.1 ± 4.1 weeks. The mean neck-shaft angle improved from 100.3° to 132.2°, the mean Harris Hip Score from 50.4 to 80.2, and the mean limb shortening reduced from 2.4 cm to 0.7 cm (all p < 0.001). No avascular necrosis, implant failure, clinically significant heterotopic ossification, or conversion to arthroplasty occurred. CONCLUSION: Proximal femoral valgus osteotomy with DHS-based fixation reliably restores hip mechanics, achieves union, and produces meaningful functional improvement in post-traumatic coxa vara, including in selected older patients with a viable femoral head.