Lisa Adele Piras

Treatment of fractures of the distal radius and ulna in toy breed dogs with circular external skeletal fixation: a retrospective study.

OBJECTIVE To evaluate the effectiveness of circular external skeletal fixation (CESF) in treating fractures of the distal radius and ulna in toy breed dogs, and to document the type and frequency of complications associated with this technique. METHODS The medical records of small breed dogs with fractures of the distal radius and ulna admitted to the University of Turin and to the Clinica Ferretti between 2002 and 2009 were retrospectively reviewed. The criteria for inclusion of cases in the study were: body weight of 5 kg or less, transverse or short oblique fracture of the distal third of the radius and ulna, no previous repair attempts, and treatment with CESF as the sole method of fixation. RESULTS Twenty fractures in 16 dogs satisfied the criteria for inclusion into this study. No signs of infection or failure of fixation were detected in any case. Mean frontal plane alignment was 4.7° ± 2.7° and mean sagittal plane alignment was 12.7° ± 7.2°. Postoperative complications occurred in one patient. All fractures achieved union. Mean time until radiographic evidence of a bridging callus and subsequent implant removal was 71 days (range: 30-120). CONCLUSIONS The results of this study support the use of CESF for treatment of fractures of the distal radius and ulna in toy breed dogs as an alternative to other methods of fracture fixation. However, this technique requires a series of follow-up examinations to evaluate the stability of the apparatus, the soundness of the wires and to determine the appropriate time for implant removal.

Effects of antebrachial torsion on the measurement of angulation in the frontal plane: A cadaveric radiographic analysis

OBJECTIVES To quantify the effect of ante- brachial torsion on the miscalculation of radial valgus measured radiographically and to assess a radiographic positioning method used to mitigate torsion-associated artifactual miscalculation of concurrent frontal plane angulation. METHODS A canine cadaveric forelimb was used to model different combinations of valgus and external torsion. Valgus was induced in the limb in increments of five degrees, radiographic images were taken at each increment, and the observed radiographic valgus was measured. Various angles of torsion were then induced and the process was repeated for a range of torsional angles at 15° increments. For the second objective, the study was repeated with the forelimb rotationally re-positioned to mirror the degree of the induced torsion of the deformity at each valgus and torsion iteration. RESULTS Both zero degrees and 15° torsional iterations possessed mean artifactual valgus (AV) values between zero and five degrees for every valgus increment. With torsion of 30° and higher, mean AV values varied widely and did not fall within the zero to five degree accepted range. Rotationally re-positioning the limb in an attempt to alleviate the AV discrepancies resulted in the 30° torsional group having acceptable AV values for valgus values between zero and 20°. CLINICAL SIGNIFICANCE Increasing ante- brachial torsion interferes with accurate radiographic measurement of frontal plane deformities. Radiographically repositioning the limb allows the accurate calculation of more valgus and torsion combinations, but still results in miscalculations of more complex deformities.

Minimally Invasive Plate Osteosynthesis Fracture Reduction Techniques in Small Animals

Indirect fracture reduction is used to align diaphyseal fractures in small animals when using minimally-invasive fracture repair. Indirect reduction achieves functional fracture reduction without opening the fracture site. The limb is restored to length and spatial alignment is achieved to ensure proper angular and rotational alignment. Fracture reduction can be accomplished using a variety of techniques and devices, including hanging the limb, manual traction, distraction table, external fixators, and a fracture distractor.

Pelvic limb alignment in small breed dogs:a comparison between affected and free subjectsfrom medial patellar luxation

Small breed dogs are 12 times more likely to develop medial patellar luxation (MPL) than large breed dogs and breed predisposition has been reported. Many surgical techniques are available for correction of patellar luxation in dogs. However, recent studies reported an 8% incidence of reluxation when traditional techniques are used. The relatively high frequency of major complications and patellar reluxation may be partially caused by inadequate appreciation of the underlying skeletal deformity and subsequent incorrect selection and application of traditional techniques. The aims of this study were to report the normal values of the anatomic and mechanical joint angles of the femur and tibia in small breed dogs and to compare these data to a population of small breed dogs affected by different degrees of MPL. Normal values of the anatomic and mechanical angles of the femur are similar to the ones reported in literature in Pomeranian dogs. Normal values of the anatomic and mechanical angles of the tibia have been described for the first time. Significant differences were found between normal population and dogs affected by grade 4 MPL in relation to anatomical Lateral Distal Femoral Angle (aLDFA), mechanical Medial Proximal Tibial Angle (mMPTA), and mechanical Caudal Proximal Tibial Angle (mCaPTA).

Distal femoral osteotomy using a novel deformity reduction device

Distal femoral osteotomy is a surgical procedure used to correct patellar luxation, secondary to a femoral deformity. A distal femoral osteotomy using the tibial plateau levelling osteotomy-jig to temporarily provide stability of the distal femoral osteotomy, maintaining limb alignment in the frontal and axial planes prior to internal plate fixation of the osteotomy, has been described. This report describes a novel jig named Deformity Reduction Device (DRD). This device was developed with the specific aim of increasing precision and predictability during corrective osteotomy execution in order to be consistent with the preoperative planning. The distal femoral osteotomy DRD-assisted procedure is described in detail, discussing the theoretical and practical principles of the application.

Comparison of osteotomy technique and jig type in completion of distal femoral osteotomies for correction of medial patellar luxation. An in vitro study.

OBJECTIVES Femoral osteotomies are frequently completed to correct malalignment associated with patellar luxation. The objectives of this study were to compare the use of: 1) two different types of jig; and 2) different types of osteotomy in the realignment of canine femoral bone models which possessed various iterations of angular deformity. METHODS Models of canine femora possessing distal varus, external torsion and a combination of varus and torsion underwent correction utilizing two alignment jigs (Slocum jig and Deformity Reduction Device) and either a closing wedge ostectomy (CWO) or an opening wedge osteotomy (OWO). Post-correctional alignment was evaluated by radiographic assessment and compared between groups. RESULTS The use of the Slocum jig resulted in frontal plane overcorrection when used with CWO in models of femoral varus, and when used with OWO in models of femoral varus and external torsion when compared to other techniques. The Deformity Reduction Device tended to realign the frontal plane closer to the post-correction target value in all angulation types. The use of both jigs resulted in undercorrection in the transverse plane in models with varus and torsion. CLINICAL SIGNIFICANCE Jig selection and osteotomy type may lead to different post-correctional alignment results when performing distal femoral osteotomies. Whereas OWO allows accurate correction when used with either jig to address frontal plane deformities, the Deformity Reduction Device can be utilized with both CWO and OWO to correct torsion-angulation femoral deformities to optimize frontal plane alignment.

Treatment of antebrachial and crural septic nonunion fractures in dogs using circular external skeletal fixation: a retrospective study

OBJECTIVE To evaluate the outcome of treatment of antebrachial and crural septic non-union fractures in dogs using circular external skeletal fixation (CESF), and to document the type and frequency of complications associated with this technique. METHODS The medical records of all dogs with infected antebrachial and crural non-union fractures treated using the methods of Ilizarov at the Department of Animal Pathology of the University of Turin between 2006 and 2011 were retrospectively reviewed. Only dogs in which radiographic and clinical assessment were available at the time of CESF removal were included in the study. RESULTS Twenty-three dogs met the inclusion criteria. Twenty nonunion fractures treated with CESF healed and three did not. The latter three cases underwent amputation of the affected limb. In the 20 dogs that achieved bone union, six had minor complications and five had major complications. The mid-term outcome was judged to be excellent (n = 11), good (n = 6), fair (n = 2), or poor (n = 4). CONCLUSIONS The results of this study support the use of CESF for the management of antebrachial and crural septic nonunion fractures in dogs. Union was achieved in the majority of dogs and the complication rate was acceptable, considering the severity of the nonunion fractures that were managed in this fashion.

MINIMALLY INVASIVE METATARSAL FRACTURE REPAIR WITH LOCKING PLATES IN A GUANACO (LAMA GUANICOE)

Abstract:  An open grade I transverse diaphyseal fracture of the metatarsal bone in a 5-yr-old female guanaco (Lama guanicoe) was successfully stabilized with a locking plate system, which is a minimally invasive approach. A conical coupling screw-plate locking system with 3.0-mm-thick plates and 3.5-mm locking head screws was applied, after closed and indirect reduction of the bone segments, with an orthogonal configuration of the plates. The implants were protected postoperatively with a splinted bandage. The fracture healed without complications, the limb function was successfully recovered, and no major complications were observed at the 2-yr follow-up. The surgical procedure was carried out with biologic internal fixation supports and an adequate functional union within a time period similar to that reported for this species following other fracture fixation methods. This case highlights the potential benefit of combining minimally invasive plate osteosynthesis and plate-locking systems for fracture repair in camelids.