Treatment of a Periarticular Tibial Fracture in a Foal with a Hybrid External Fixator ROBERTA FERRO DE GODOY, DScVM, RICHARD R. FILGUEIRAS, MS, LI ´ LIAN A. GONTIJO, DVM, FA ´ BIO HENRIQUE BEZERRA XIMENES, DVM, LIANA VILLELA DE GOUVE ˆ A, DVM, CRISTIANE DA SILVA PEREIRA, DVM, RICARDO M. ALMEIDA, MS, CECI RIBEIRO LEITE, DVM, ANTO ˆ NIO RAPHAEL T. NETO, DScVM, and JOSE ´ RENATO JUNQUEIRA BORGES, DScVM Objective—To report repair of a right proximal tibial Salter-Harris type II fracture in a foal with a hybrid external fixator (HEF). Study Design—Case report. Animals—A 5-month-old male foal. Methods—After open surgical reduction, an HEF built with wires, 2 half-rings, 3 half-threaded connecting rods, and Schanz pins was used to stabilize the fracture. Results—Immediately after surgery, the foal had relatively good weight bearing. The HEF was removed at 60 days after radiographic confirmation of healing. Conclusions—HEF can be used to stabilize a proximal tibial Salter-Harris type II fracture in a 5-month-old foal. Clinical Relevance—HEF should be considered as another option for repair of proximal tibial Salter-Harris type II fractures in foals. r Copyright 2009 by The American College of Veterinary Surgeons INTRODUCTION T HE MOST common fracture involving the proximal tibial physis in young foals is a Salter-Harris type II with a lateral metaphyseal component that typically in- volves up to 1/3 of the physeal surface. 1–3 Foals with minimal fragment displacement can be managed conser- vatively; however, with progressive displacement and val- gus deformity surgical stabilization is recommended. The likelihood of limb length differences after surgery and prognosis for racing remain unknown. 4 Repair methods for long bone physeal fractures in foals include plates 5–7 ; screw fixation in lag fashion 2,8 ; transverse pins (Charnley apparatus) 9 ; and crossed pin fixation. 10 Proximal tibial physeal fractures in foals have been repaired by plates, 7 cancellous bone screws, 2 and Steinman pins combined with a Charnley apparatus. 9 To our knowledge, external skeletal fixation (ESF) devices have not been used to repair this fracture type in foals. Advantages of ESF devices are weight-bearing ability immediately after surgery, normal joint mobility, and an optimal environment for osteosynthesis and wound heal- ing without the need for an implant in the fracture site. 11 For large animal use, ESF devices must be sufficiently rigid, well tolerated, and easily applied. 12 A hybrid external fixator (HEF) combines the circular Ilizarov fixator and the linear ESF 11 types and might be useful for proximal tibial physeal fracture repair in foals. The stability of the Ilizarov fixator, with its rings and crossed wires, depends on bone position within the fix- ator rings and fixation wire tension 13 ; however, a disad- vantage is difficulty in application in some anatomic locations and thus HEF of various configurations are gaining popularity in human surgical applications. 14 HEF is based on Ilizarov external fixator concepts using tensioned wires and is indicated for treatment of tibial Address reprint requests to Dr. Roberta Ferro de Godoy, DScVM, Hospital Escola de Grandes Animais UnB, Galpa˜ o 04, Granja do Torto, CEP 70636-200, Brası´ lia, DF, Brazil. E-mail: robertagodoy@unb.br. Submitted August 2008; Accepted March 2009 From the Large Animal Veterinary Teaching Hospital, University of Brası´lia, Brası´lia, DF, Brazil. r Copyright 2009 by The American College of Veterinary Surgeons 0161-3499/09 doi:10.1111/j.1532-950X.2009.00549.x 650 Veterinary Surgery 38:650–653, 2009