Proximal femoral deformity correction and total hip arthroplasty in a dog using 3D printed custom guides.

Abstract

To report the successful correction of a proximal femoral deformity (PFD) and total hip arthroplasty (THA) in a dog with the use of three-dimensionally (3D) printed custom surgical guides (CSGs). Case report. One-year-old, male neutered, Goldendoodle. Uniapical proximal varus and recurvatum femoral deformity (PFD) precluded femoral stem placement for THA, which was indicated for severe hip dysplasia. Using CT-derived bone and implant models, custom ostectomy and reduction guides for deformity correction were designed. A 13-hole 3.5 mm locking compression plate was contoured and applied to 3D printed models of the corrected femur and screw trajectory holes were incorporated into the CSGs. A caudolateral closing wedge ostectomy of the proximal femur was achieved with the aid of the CSGs and precontoured plate to within 2° of varus and 1° of recurvatum of the virtual surgical plan. Placement of a press-fit femoral stem was achieved with 7° of varus and 9° of caudal angulation. The plate was secured using six locking screws, two cortical screws, and two 18-gauge double-loop cerclage wires. No lameness and normal range of motion of the hip were observed on clinical examination 3 months after surgery. Radiographs at 3 and 6months revealed static implant positioning, and complete bony union at the ostectomy site. Virtual surgical planning and CSGs led to successful concurrent THA and femoral deformity correction.