Accuracy of Patient-Specific 3D Printed Drill Guides in the Placement of a Canine Coxofemoral Toggle Pin through a Minimally Invasive Approach.

OBJECTIVE: The aim of this study was to evaluate the accuracy of patient-specific three-dimensional printed drill guides (3D-PDG) for the placement of a coxofemoral toggle via a minimally invasive approach. MATERIALS AND METHODS: Pre-procedure computed tomography (CT) data of 19 canine cadaveric hips were used to design a cadaver-specific 3D-PDG that conformed to the proximal femur. Femoral and acetabular bone tunnels were drilled through the 3D-PDG, and a coxofemoral toggle pin was placed. The accuracy of tunnel placement was evaluated with post-procedure CT and gross dissection. RESULTS: Coxofemoral toggle pins were successfully placed in all dogs. Mean exit point translation at the fovea capitis was 2.5 mm (0.2-7.5) when comparing pre- and post-procedure CT scans. Gross dissection revealed the bone tunnel exited the fovea capitis inside (3/19), partially inside (12/19) and outside of (4/19) the ligament of the head of the femur. Placement of the bone tunnel through the acetabulum was inside (16/19), partially inside (1/19) and outside (2/19) of the acetabular fossa. Small 1 to 2 mm articular cartilage fragments were noted in 10 of 19 specimens. CLINICAL SIGNIFICANCE: Three-dimensional printed drill guide designed for coxofemoral toggle pin application is feasible. Errors are attributed to surgical execution and identification of the borders of the fovea capitis on CT data. Future studies should investigate modifications to 3D-PDG design and methods. Three-dimensional printed drill guide for coxofemoral toggle pin placement warrants consideration for use in select clinical cases of traumatic coxofemoral luxation.

Single oblique osteotomy for correction of antebrachial angular and torsional deformities in a dog.

CASE DESCRIPTION A 9-month-old 4.6-kg (10.1-lb) spayed female Shih Tzu was examined for a 4-week history of left forelimb lameness. CLINICAL FINDINGS Moderate left forelimb lameness was present when weight bearing, accompanied by buckling of the left carpal joint and moderate signs of pain with hyperextension of the elbow joint. A 32° angular deformity of the left radius in a 45° craniomedial oblique plane (equivalent to 23° valgus and 23° procurvatum) and a 55° external torsional deformity were measured on 3-D reconstructed CT images. Humeroulnar incongruity of the left elbow joint was also evident. Single oblique osteotomy (SOO) and dynamic proximal ulnar osteotomy were recommended. TREATMENT AND OUTCOME Creation of a 3-D printed bone model from reconstructed CT images aided surgical planning. The SOO was located 45° medial to the sagittal plane of the left radius at the level of the center of rotation of angulation. The SOO was oriented 32° distolaterally from the transverse plane of the radius and traversed the left ulna. The bones were rotated along the osteotomy into grossly proper alignment and stabilized with a plate and bone screws. Dynamic proximal ulnar osteotomy was then performed. Six months after surgery, radiographs showed remodeling at the SOO site and the lameness had resolved. The owners expressed satisfaction with the outcome. CLINICAL RELEVANCE In dogs with angular and torsional long bone deformities, SOO may be a viable alternative to wedge osteotomies. The SOO simultaneously addressed angular and torsional deformities without bone loss and provided rigid internal fixation.

Risk Factors for Dehiscence of Stapled Functional End-to-End Intestinal Anastomoses in Dogs: 53 Cases (2001-2012).

OBJECTIVE: To identify risk factors for dehiscence in stapled functional end-to-end anastomoses (SFEEA) in dogs. STUDY DESIGN: Retrospective case series. ANIMALS: Dogs (n = 53) requiring an enterectomy. METHODS: Medical records from a single institution for all dogs undergoing an enterectomy (2001-2012) were reviewed. Surgeries were included when gastrointestinal (GIA) and thoracoabdominal (TA) stapling equipment was used to create a functional end-to-end anastomosis between segments of small intestine or small and large intestine in dogs. Information regarding preoperative, surgical, and postoperative factors was recorded. RESULTS: Anastomotic dehiscence was noted in 6 of 53 cases (11%), with a mortality rate of 83%. The only preoperative factor significantly associated with dehiscence was the presence of inflammatory bowel disease (IBD). Surgical factors significantly associated with dehiscence included the presence, duration, and number of intraoperative hypotensive periods, and location of anastomosis, with greater odds of dehiscence in anastomoses involving the large intestine. CONCLUSION: IBD, location of anastomosis, and intraoperative hypotension are risk factors for intestinal anastomotic dehiscence after SFEEA in dogs. Previously suggested risk factors (low serum albumin concentration, preoperative septic peritonitis, and intestinal foreign body) were not confirmed in this study.