Initial Clinical Experience with the IMEX™ Circular External Skeletal Fixation System

Summary

The IMEX™ Circular External Skeletal Fixation (CESF) System was used to stabilize fractures (12 radius and ulna and five tibia and fibula) in 15 dogs and two cats and arthrodeses (two pancarpal, one talocrural and one pantarsal) in four dogs. The ages of the animals with fractures ranged from six months to nine years (mean ± SD: 2.7 ± 2.5 years; median: 2.0 years) and the body weights of dogs with fractures ranged from 5.4 kg to 48.6 kg (mean ± SD: 21.3 ± 12.6 kg; median: 22.7 kg). The ages of the dogs having arthrodeses ranged from eight months to two years (mean ± SD: 18±10 months; median: 18 months) and body weights of dogs with arthrodeses ranged from 19.0 kg to 29.1 kg (mean ± SD: 22.7 ± 4.7 kg; median: 21.4 kg). Ten fractures were open and four had been previously managed with another form of stabilization. Ten fractures were comminuted and all of the fractures involved the diaphysis; two extended to the distal metaphysis. An extensive open reduction was used on three, a limited open reduction on seven and a closed reduction on seven fractures. Arthrodeses were performed via a limited open approach, for debridement of the articular cartilage and implantation of a cancellous bone graft. Most animals placed substantial weight on the affected limb within a few days following the operations. Wire and pin track inflammation was the most common complication during the convalescent period and was often associated with a decrease in weight-bearing. Sixteen fractures achieved radiographic union (mean ± SD: 46 ± 13 days; median: 43 days) long-term function (direct examination: mean ± SD: 76 ± 38 days; median: 43 days; telephone communication: mean ± SD: 366 ± 247 days; median: 381 days) was assessed as excellent in 10 animals and good in seven. All of the arthrodeses achieved radiographic union (mean ± SD: 74 ± 31 days; median: 71 days). Longterm function (direct examination: mean ± SD: 185 ± 182 days; median: 102 days; telephone communication: mean ± SD: 485 ± 22 days; median: 590 days) was assessed as good in two dogs and fair in two dogs. Our results establish the utility of the IMEX™ CESF System for stabilizing fractures and performing arthrodeses in dogs and cats.

The IMEX™ Circular External Fixator System was used to stabilize radius and ulna or tibia and fibula-fractures in 15 dogs and two cats and perform arthrodeses ir four dogs. Sixteen fractures and all four arthrodeses achieved radiographic union. Limb function was assessed as excellent in ten animals, good in nine animals and fair in two dogs.

Presented at the 23rd Annual Conference of the Veterinary Orthopaedics Society, Telluride, CO, USA March 5, 1996 University of Florida Journal Series #547.

Keywords

Fracture - arthrodesis - circular external fixation

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