Correcting angular limb deformities of radius-ulna and tibia in nine dogs using computer-assisted spider frame system

Abstract

In this study, angular deformities in 9 dogs, including 8 antebrachium and 1 tibia, were corrected using hexapod external fixators with the help of the computer-aided Spider Frame system.Preoperative planning included measurement of craniocaudal and mediolateral angular deformities, rotational deformity, length deficit, as well as determination of the source of the deformity and assembly of the frame.Joint lines and osteotomy/ostectomy lines were determined according to CORA points determined during preoperative measurements. Proximal and distal rings were placed. After the installation of the spider, radial/ tibial osteotomy/ostectomy was performed at the CORA point of the radius/tibia. After the operation, craniocaudal and mediolateral radiographs were taken in all cases. Ring dimensions, angular deformity values (including angulation, translation and rotation) and the degree of shortening were evaluated by radiographs. These data were entered into the web-based Spider software to generate correction prescriptions, after which the length and deformity correction process started on postoperative days 3-5. Functional results were excellent in seven cases and good in the other two cases. Long-term cosmesis was good to excellent in all cases.In conclusion, Spider Frame is a new generation external fixator system with many technical advantages and we recommend its use in appropriate cases.

Keywords

• dog
• angular deformity
• corrective osteotomy
• computer-assisted spider frame system