Use of hinged circular fixator constructs for the correction of crural deformities in three dogs.

BACKGROUND: Hinged circular external skeletal fixator constructs are used to perform sequential correction of angular limb deformities, often with resultant limb segment lengthening, via distraction osteogenesis. Although there are several reports describing the use of these constructs for correction of antebrachial deformities in dogs, there is little information regarding their use on other limb segments. This report describes the use of hinged circular fixator constructs for the correction of acquired crural deformities in three skeletally immature dogs. CASE REPORTS: Two dogs had purely frontal plane deformities (one valgus, one varus) and the third dog had frontal (valgus) and sagittal (recurvatum) components to its deformity. At the time of long-term evaluation, frontal plane angulation relative to the contralateral limb improved from 40° to 22° of valgus, 30° to 5° of valgus, and 20° to 1° of varus in the three individual dogs. Tibial length discrepancies of 12% and 22% that were initially present in two dogs were improved to 6% and 10%, respectively, of the contralateral tibial length at the time of final evaluation; both dogs had compensatory growth of the ipsilateral femur and all dogs had an excellent functional outcome. CONCLUSION: These cases illustrate the value of using hinged circular fixator constructs for correction of crural angular deformities, particularly when length discrepancies of the tibia are present.

Elbow arthrodesis following a pathological fracture in a dog with bilateral humeral bone cysts.

A 10-month-old Yorkshire Terrier was referred for evaluation of an intermittent right thoracic limb lameness that acutely progressed to non-weight-bearing. A diagnosis of bilateral bone cysts of the humeral condyles with a pathologic fracture of the lateral aspect of the right humeral condyle was given following radiographic and histopathologic examination. Bilateral pathology necessitated consideration of treatment modalities other than amputation of the limb, as previously reported. Arthrodesis of the right elbow using a 2.0 mm locking bone plate was performed. The dog did not experience any complications associated with the procedure or the contralateral bone cyst.