Computer-Assisted Surgery Using 3D Printed Saw Guides for Acute Correction of Antebrachial Angular Limb Deformities in Dogs

Authors: 
Worth AJ, Crosse KR, Kersley A.
Vet Comp Orthop Traumatol. 2019 May;32(3):241-249. doi: 10.1055/s-0039-1678701.

OBJECTIVE: The aim of this study was to report the use of custom saw guides produced using computed tomographic imaging (CT), computer simulation and three-dimensional (3D) printing to aid surgical correction of antebrachial deformities in six dogs.

MATERIALS AND METHODS:  Antebrachial limb deformities in four small, and two large, breed dogs (seven limbs) were surgically corrected by a radial closing wedge ostectomy and ulnar osteotomy. The location and orientation of the wedge ostectomy were determined using CT data, computer-assisted planning and production of a saw guide in plastic using a 3D printer. At surgery, the guide was clamped to the surface of the radius and used to direct the oscillating saw blade. The resultant ostectomy was closed and stabilized with a bone plate.

RESULTS: Five limbs healed without complications. One limb was re-operated due to a poorly resolved rotational component of the deformity. One limb required additional stabilisation with external fixation due to screw loosening. The owners of five dogs completed a Canine Orthopedic Index survey at a follow-up period of 37 to 81 months. The median preoperative score was 3.5 and the median postoperative score was 1, representing an overall positive effect of surgery. Radiographically, 5/7 limbs were corrected in the frontal plane (2/7 were under-corrected). Similarly, 5/7 limbs were corrected in the sagittal plane, and 2/7 were over-corrected in the sagittal place.

CONCLUSIONS: Computer-aided design and rapid prototyping technologies can be used to create saw guides to simplify one-stage corrective osteotomies of the antebrachium using internal fixation in dogs. Despite the encouraging results, accurate correction of rotational deformity was problematic and this aspect requires further development.