Veterinary and Comparative Orthopaedics and Traumatology (VCOT) Veterinary and Comparative Orthopaedics and Traumatology (VCOT) vcot de-de Tue, 24 Oct 17 02:26:47 +0200 Laura Lenz, Managing Editor of VCOT Fond farewell and the best wishes for the future Laura Lenz, Managing Editor of VCOT Fond farewell and the best wishes for the future. K. Johnson 27926 2017-09-13 11:10:25 Efficacy of an oral nutraceutical for the treatment of canine osteoarthritis Objectives: To assess the safety and efficacy of an orally administered nutraceutical (Glu/CS+; + for additional ingredient) for the treatment of clinical osteoarthritis (OA) in dogs. Methods: In this double-blind, randomized, placebo-controlled clinical trial, client-owned dogs with clinical signs of OA in one or more joints were assigned to a Glu/CS+ (n = 30) or placebo (n = 30) group. Dogs were administered Glu/CS+ or placebo orally and wore an activity monitor (AM) continuously throughout a 97 day study period. Prior to the initiation of the treatment, seven days of baseline activity was collected. On days –7, 30, 60 and 90 of the study, owners completed a patient assessment form (Canine Brief Pain Inventory). Data between groups were compared. Results: No serious adverse events were reported. No difference was found between groups when evaluating daily activity counts during the seven-day pre-treatment period and the 90-day treatment period. Owner assessment (pain interference and pain severity scores) improved over the 90-day treatment period for both groups, however no difference was found between treatment groups. Conclusions: Treatment with oral Glu/CS+ for a 90 day treatment period when compared to placebo treatment did not result in a significant increase in activity counts in dogs with clinical OA. However, owner assessment scores similarly improved throughout the study period for dogs in both groups, suggesting a caregiver placebo effect in this outcome measure.... R. M. Scott (1), R. Evans (2), M. G. Conzemius (1) 27780 2017-08-01 17:40:46 The influence of aluminium, steel and polyurethane shoeing systems and of the unshod hoof on the... Objectives: To evaluate the damage inflicted by an unshod hoof and by the various horseshoe materials (steel, aluminium and polyurethane) on the long bones of horses after a simulated kick. Methods: Sixty-four equine radii and tibiae were evaluated using a drop impact test setup. An impactor with a steel, aluminium, polyurethane, or hoof horn head was dropped onto prepared bones. An impactor velocity of 8 m/s was initially used with all four materials and then testing was repeated with a velocity of 12 m/s with the polyurethane and hoof horn heads. The impact process was analysed using a high-speed camera, and physical parameters, including peak contact force and impact duration, were calculated. Results: At 8 m/s, the probability of a fracture was 75% for steel and 81% for aluminium, whereas polyurethane and hoof horn did not damage the bones. At 12 m/s, the probability of a fracture was 25% for polyurethane and 12.5% for hoof horn. The peak contact force and impact duration differed significantly between ‘hard materials’ (aluminium and steel) and ‘soft materials’ (polyurethane and hoof horn). Clinical significance: The observed bone injuries were similar to those seen in analogous experimental studies carried out previously and comparable to clinical fracture cases suggesting that the simulated kick was realistic. The probability of fracture was significantly higher for steel and aluminium than for polyurethane and hoof horn, which suggests that the horseshoe material has a significant influence on the risk of injury for humans or horses kicked by a horse.... M. Sprick (1), A. Fürst (1), F. Baschnagel (2), S. Michel (2), G. Piskoty (2), S. Hartnack (3), M. A. Jackson (1) 27779 2017-08-01 17:26:25 Prevalence, treatment and outcome of patellar luxation in dogs in Italy Objective: To determine the prevalence of patellar luxation in dogs in Italy and its relation to signalment, the frequency and the type of postoperative complications and the outcome of treatment, and to compare the findings with those of other studies. Materials and methods: The medical records from four referral clinics were searched for dogs with orthopaedic disorders referred from 2009 to 2014. From these data, the records of dogs with patellar luxation were identified, and the signalment, age and body weight, grade, side and direction of patellar luxation, treatment, postoperative complications, and outcome were retrieved. Univariate and multivariate statistical analyses were used to evaluate the data. Results: Of 8,694 canine orthopaedic cases, fractures not included, patellar luxation was diagnosed in 559 dogs (801 stifles). Mixed breed dogs were most commonly affected (18%), 85% of the luxations were medial, and 52% of the dogs were female. Of the 559 dogs examined, 400 (574 stifles) met the inclusion criteria for treatment evaluation. Minor complications occurred in five percent of the dogs, and major complications in 16%, including recurrence of patellar luxation in seven percent of the dogs. The outcome was good in 88% of stifles, fair in two percent, and poor in 10%. Clinical significance: Although patellar luxation was more common in small breed dogs, it also was diagnosed in a significant number of large breed dogs, which included medial patellar luxation in 73% and lateral patellar luxation in 27% of stifles. Body weight and grade of luxation were the only variables statistically correlated with surgical complications.... F. Bosio (1), A. Bufalari (2), B. Peirone (3), M. Petazzoni (4), A. Vezzoni (5) 27778 2017-08-01 17:21:19 2017 VOS Abstracts 27744 2017-07-24 13:56:38 Ahead of print: Erratum to: Computed tomographic evaluation of femoral and tibial conformation in... 27717 2017-07-10 17:19:26 Percutaneous tibial physeal fracture repair in small animals: technique and 17 cases Objectives: To retrospectively describe cases treated via percutaneous tibial physeal fracture repair (PTPFR), using intra-operative fluoroscopy (IFL) or digital radiography (DR). To describe a technique (“spiking”), used to treat tibial tuberosity avulsion fractures. Methods: Clinical data of 14 dogs and three cats were included. The “spiking” technique was described. Results: Intra-operative fluoroscopy (n = 11) and DR (n = 6) were successfully used in 11 tibial tuberosity avulsion fractures, one combined proximal physeal and tibial tuberosity avulsion fracture, and five distal tibial/fibular physeal fractures. Surgery times ranged from eight to 54 minutes. The “spiking” technique was successfully applied in six tibial tuberosity avulsion fracture cases. Return to function was at a mean (± standard deviation) of 1.9 (± 1.6) weeks. Long-term (>12 months; n = 17) follow-up was available at a mean of 40.6 (± 13.4) months. Major complications consisted of skin irritation from a pin (distal tibia / fibula physeal fracture case; 8 weeks post-PTPFR), and a bilateral grade II medial patella luxation (tibial tuberosity avulsion fracture case; 1.5 years post-PTPFR). One case developed a mild tibial tuberosity avulsion fracture re-avulsion. All conditions in these three cases were not of clinical concern at follow-up and final outcome was graded as good in these and excellent in the other 14 cases. Clinical significance: Percutaneous tibial physeal fracture repair can be considered as a technique to treat tibial physeal fractures. The “spiking” technique was successfully applied in six dogs. A larger, prospective case series is indicated to provide additional clinical information.... D. J. F. von Pfeil (1, 2), M. Glassman (1), M. Ropski (1) 27682 2017-06-21 11:52:07 A structural numerical model for the optimization of double pelvic osteotomy in the early treatment... Background: Double pelvic osteotomy (DPO) planning is usually performed by hip palpation, and on radiographic images which give a poor representation of the complex three-dimensional manoeuvre required during surgery. Furthermore, bone strains which play a crucial role cannot be foreseen. Objective: To support surgeons and designers with biomechanical guidelines through a virtual model that would provide bone stress and strain, required moments, and three-dimensional measurements. Methods: A multibody numerical model for kinematic analyses has been coupled to a finite element model for stress/strain analysis on deformable bodies. The model was parametrized by the fixation plate angle, the iliac osteotomy angle, and the plate offset in ventro-dorsal direction. Model outputs were: acetabular ventro-version (VV) and lateralization (L), Norberg (NA) and dorsal acetabular rim (DAR) angles, the percentage of acetabular coverage (PC), the peak bone stress, and moments required to deform the pelvis. Results: Over 150 combinations of cited parameters and their respective outcome were analysed. Curves reporting NA and PC versus VV were traced for the given patient. The optimal VV range in relation to NA and PC limits was established. The 25° DPO plate results were the most similar to 20° TPO. The output L grew for positive iliac osteotomy inclinations. The 15° DPO plate was critical in relation to DAR, while very large VV could lead to bone failure. Clinical significance: Structural models can be a support to the study and optimization of DPO as they allow for foreseeing geometrical and structural outcomes of surgical choices.... E. Zanetti (1), M. Terzini (2), L. Mossa (2), C. Bignardi (2), P. Costa (3), A. L. Audenino (2), A. Vezzoni (4) 27673 2017-06-20 16:42:27 Symmetrical brachydactyly in a dog Congenital malformations of the canine manus and pes are infrequently reported in the veterinary literature. This includes brachydactyly which is a general term used to indicate the shortening of digits due to abnormal development of the phalanges, metacarpals, or metatarsals. This case report describes isolated brachydactyly in a one-year-old male Maremma Sheepdog affecting all of the phalanges, metacarpals, and metatarsals of digits two through five. This condition was confirmed by determining the length of each phalanx, metacarpal, and metatarsal of the affected dog as well as an unaffected littermate. The affected dog’s metacarpal, metatarsal, and phalanx lengths ranged from 50% to 77% of that of the unaffected sibling. Other abnormalities found on physical examination as well as on radiographic imaging are discussed. M. T. Cray (1), U. Krotscheck (2), A. J. Fischetti (1), K. Tong (1) 27672 2017-06-20 16:41:46 Comparison of complications following tibial tuberosity advancement and tibial plateau levelling... Objectives: To analyse and compare major complications in dogs ≥50 kg undergoing tibial tuberosity advancement (TTA) or tibial plateau levelling osteotomy (TPLO) for treatment of cranial cruciate ligament disease. Methods: Medical records and radiographs of client-owned dogs (≥50 kg) treated for cranial cruciate ligament disease with either TTA or TPLO between January 2011 and November 2015 were reviewed. Ninety-one TTA cases and 54 TPLO cases met the study inclusion criteria. All complications within one year of surgery were recorded. Major complications were those requiring surgical revision or intervening medical therapy to resolve. Logistic regression analysis evaluated for associations with major complication occurrence. Major complications were statistically compared between TTA and TPLO treatment groups. Results: Incidence of major complications following TTA and TPLO surgery were 19.8% and 27.8%, respectively. Surgical site infection (SSI) was the single most common major complication following both TTA (15.4%) and TPLO (25.9%) surgery. There were no significant differences between TTA and TPLO treatment regarding the rate of SSI, surgical revision, or overall occurrence of major complications. Postoperative antibiotic therapy significantly reduced the risk of a major complication in all dogs ≥50 kg (p = 0.015; OR: 0.201: 95%CI: 0.055–0.737). Clinical significance: Major complications occurred frequently following TTA and TPLO treatment of cranial cruciate ligament disease in dogs ≥50 kg. The increased chance for SSI should be considered and postoperative antibiotic therapy is recommended.... E. C. Hans (1), M. D. Barnhart (1), S. C. Kennedy (1), S. J. Naber (2) 27671 2017-06-20 16:38:07 Guidelines for surgical approaches for minimally invasive plate osteosynthesis in cats Objectives: Minimally invasive plate osteosynthesis (MIPO) is one of the most recent fixation techniques that embody the concept of biological osteosynthesis. Several studies evaluating MIPO in dogs have been published in the recent years. However, there are few clinical reports of MIPO in cats and no description of the surgical approaches. The purpose of our study was to describe the safe corridors for plate insertion in cats using the MIPO technique. Methods: The surgical approaches for the humerus, radius-ulna, femur and tibia were developed after reviewing the described techniques and surgical approaches for MIPO in dogs, while considering any relevant anatomical difference between dogs and cats. Following the MIPO approaches, the limbs were anatomically dissected and the relationship between proximal and distal positions of the implants and neurovascular structures was noted. Results: The surgical approaches developed for the humerus and radius-ulna differed from what had been reported previously, because relevant anatomical differences were found between dogs and cats. Anatomical landmarks for safe plate application were described for all the major long bones in cats. No damage to vital structures following plate insertion was detected in the dissection. Clinical significance: In this cadaveric study, we evaluated the safety of the surgical approaches for MIPO in cats. By respecting the anatomical landmarks described in this report, damage to the neurovascular structures can be avoided performing the MIPO technique in cats.... P. A. Schmierer (1), A. Pozzi (1) 27670 2017-06-20 16:35:27 Impact of femoral varus on complications and outcome associated with corrective surgery for medial... Objectives: To evaluate the association of femoral varus with postoperative complications and outcome following standard corrective surgery for medial patellar luxation (MPL) without distal femoral osteotomy (DFO) in dogs. Methods: In a retrospective study spanning a 12 year period, 87 stifles with MPL that were treated by standard surgical techniques were included. Inclination angle (ICA), femoral varus angle (FVA), anatomical lateral distal femoral angle (aLDFA), and mechanical lateral distal femoral angle (mLDFA) were measured. Postoperative complications were noted and outcome evaluated. Associations between potential risk factors and both complication rate and outcome were assessed. Results: Postoperative complications occurred in 19 stifles, five of which were major. There was no evidence of an association between FVA (p = 0.41) or aLDFA (p = 0.38) and any complication. There was also no evidence of an association between FVA (p = 0.31) or aLDFA (p = 0.38) and any major complication. Dogs with a larger aLDFA had increased odds of a poorer outcome (p = 0.01) as did dogs that suffered a major complication (p = 0.0001). Clinical significance: Based on radiographic measurements, there is no evidence of an association between FVA and the incidence of postoperative complications following standard MPL correction. Traditional surgical techniques appear to be appropriate for most cases of MPL and further work is required to better define selection criteria for including DFO in the treatment of these cases.... K. L. Perry (1), R. J. Adams (2), S. J. Andrews (1), C. Tewson (3), M. Bruce (4) 27669 2017-06-20 16:33:08 Effect of headless compression screw on construct stability for centre of rotation and... Objective: To compare the biomechanical properties of bone and implant constructs when used for the centre of rotation and angulation (CORA) based levelling osteotomy, with and without implantation of a trans-osteotomy headless compression screw tested under three-point flexural and torsional forces; thereby determining the contribution of a trans-osteotomy headless compression screw with regards to stability of the construct. Methods: Experimental biomechanical study utilizing 12 pairs of cadaveric canine tibias. Using the CORA based levelling osteotomy (CBLO) procedure, the osteotomy was stabilized with either a standard non-locking CBLO bone plate augmented with a headless compression screw (HCS) or a CBLO bone plate alone. Tibial constructs were mechanically tested in three-point craniocaudal flexural testing or in torsion. Results: In three-point flexural testing, the difference between the two constructs was not significant. In torsion, the difference in the angle of failure between constructs with a HCS (48.46°) and constructs without a HCS (81.65°) was significant (p = 0.036). Maximum torque achieved by constructs with a HCS (21.7 Nm) was greater than those without (18.7 Nm) (p = 0.056). Stiffness differences between both groups in torsion and bending were not significant. Use of a HCS did increase the stability of the CBLO construct in torsional testing, but not in flexural testing.... M. Meyer (1), M. A. Perez (2), M. S. Hossain (2, 3), E. B. Silverman (1), R. B. Fitch (4), R. B. Wicker (2, 3) 27668 2017-06-20 16:30:16 Clinical outcome and complications of thoracic and pelvic limb stump and socket prostheses Objectives: To describe the use, quality of life, compliance, complications, and outcome of animals fitted with stump socket prostheses. Methods: Medical records of dogs fitted with a stump socket prosthesis were reviewed. Functional outcome, quality of life and complications were retrospectively assessed from an owner questionnaire. Results: Thirteen stump socket prostheses (12 dogs) were fitted for a variety of reasons including trauma, congenital abnormalities, and neoplasia. Eight dogs had a good outcome overall and four a poor outcome. Quality of life (QOL) remained good or excellent in 10/12 dogs. Nine complications were seen in 7/12 dogs, most were manageable; surgical wound complications (n = 2) and pressures sores (n = 4) were the most frequently encountered. One dog suffered multiple complications. Thoracic and pelvic limb stump socket prostheses had a similar complication rate, however all animals with a poor outcome had a thoracic limb stump socket prosthesis; two were small breed dogs (under 10 kg) and two had bilateral thoracic limb abnormalities. Clinical significance: Stump socket prostheses are feasible and versatile in animals. In correctly selected cases, good to excellent outcomes are possible. However, complications are frequent but often manageable. Further investigations are required into the risk factors for poor outcomes and prospective studies are required to assess changes in biomechanics, function, and QOL before and after fitting of a stump socket prosthesis. Until further evidence is available, careful consideration should be given before fitting bilateral thoracic limb stump socket prostheses or thoracic limb stump socket prostheses to small breed dogs.... A. Phillips (1), E. Kulendra (1), E. Bishop (2), M. Monk (3), K. Parsons (4), A. House (2) 27667 2017-06-20 16:29:31 2017 VOS Abstracts 27559 2017-05-22 13:38:33 Three-dimensional kinematics of the equine metacarpophalangeal joint using x-ray reconstruction of... X-ray reconstruction of moving morphology (XROMM) uses biplanar videoradiography and computed tomography (CT) scanning to capture three-dimensional (3D) bone motion. In XROMM, morphologically accurate 3D bone models derived from CT are animated with motion from videoradiography, yielding a highly accurate and precise reconstruction of skeletal kinematics. We employ this motion analysis technique to characterize metacarpophalangeal joint (MCPJ) motion in the absence and presence of protective legwear in a healthy pony. Our in vivo marker tracking precision was 0.09 mm for walk and trot, and 0.10 mm during jump down exercises. We report MCPJ maximum extension (walk: –27.70 ± 2.78° [standard deviation]; trot: –33.84 ± 4.94°), abduction/adduction (walk: 0.04 ± 0.24°; trot: –0.23 ± 0.35°) and external/internal rotations (walk: 0.30 ± 0.32°; trot: –0.49 ± 1.05°) indicating that the MCPJ in this pony is a stable hinge joint with negligible extra-sagittal rotations. No substantial change in MCPJ maximum extension angles or vertical ground reaction forces (GRFv) were observed upon application of legwear during jump down exercise. Neoprene boot application yielded –65.20 ± 2.06° extension (GRFv = 11.97 ± 0.67 N/kg) and fleece polo wrap application yielded –64.23 ± 1.68° extension (GRFv = 11.36 ± 1.66 N/kg), when compared to naked control (-66.11 ± 0.96°; GRFv = 12.02 ± 0.53 N/kg). Collectively, this proof of concept study illustrates the benefits and practical limitations of using XROMM to document equine MCPJ kinematics in the presence and absence of legwear.... B. A. Childs (1), B. R. Pugliese (1), C. T. Carballo (1), D. L. Miranda (2), E. L. Brainerd (3), C. A. Kirker-Head (1) 27495 2017-05-05 13:02:03 Pelvic limb alignment measured by computed tomography in purebred English Bulldogs with medial... Objectives: The aim of the study was to describe the differences in pelvic limb alignment between healthy purebred English Bulldogs and those with medial patellar luxation through the measurement of femoral and tibial angles on computed tomography images in multiplanar reconstruction modality (MPR-CT). Methods: Twenty-one purebred English Bulldogs were included and divided into two groups: one including healthy dogs (15 limbs) and the other including those with medial patellar luxation (24 limbs). Three different observers used MPR-CT to measure the following angles: anatomical lateral proximal femoral angle (aLPFA), anatomical lateral distal femoral angle (aLDFA), mechanical lateral proximal femoral angle (mLPFA), mechanical lateral distal femoral angle (mLDFA), angle of inclination of the femoral neck (AI), angle of anteversion (AA), mechanical medial proximal tibial angle (mMPTA), mechanical medial distal tibial angle (mMDTA), mechanical caudal distal tibial angle (mCdDTA), mechanical caudal proximal tibial angle (mCdPTA), and the tibial torsion angle (TTA). A Mann-Whitney U test was used to compare each variable in both groups. Results: The values for aLDFA and mLDFA in the medial patellar luxation population were significantly increased compared to healthy subjects (p <0.05). No significant differences were observed for the other variables. Clinical significance: In our population, an increased distal femoral varus was associated with medial patellar luxation. Our results could be useful to determine whether or not angular deformity of the femur is present and help determine the degree of correction necessary to restore alignment.... F. Lusetti (1), A. Bonardi (1), C. Eid (1), A. Brandstetter de Belesini (1), F. M. Martini (1, 2) 27494 2017-05-05 13:00:15 Proximal tibial metaphyseal fractures in immature dogs Objective: To describe proximal tibial metaphyseal fractures in immature dogs. Materials and methods: Medical records of immature dogs with metaphyseal fractures of the proximal tibia were reviewed and data were collected on signalment and history of trauma. Craniocaudal and mediolateral radiographs were evaluated for the determination of the bones fractured, location of the fracture within the bone, fracture configuration, and the presence of fracture segment displacement and angulation. Results: Eighteen dogs with 22 proximal tibial metaphyseal fractures fulfilled the inclusion criteria. All fractures had a curvilinear, complete fracture of the proximal tibial metaphysis. Displacement was identified in 16 fractures and angulation in 15 fractures. All affected breeds were terrier or small breed dogs less than six months of age. The majority of dogs weighed 5 kg or less at the time of injury. The most common type of trauma that occurred was a jump or fall from a short distance. Clinical significance: Proximal tibial metaphyseal fractures are an uncommon injury that occur in skeletally immature dogs from minimal trauma. Proximal tibial metaphyseal fractures have a characteristic curvilinear fracture configuration that affects mainly small breed dogs with a predominance for terrier breeds.... L. Deahl (1), R. Ben-Amotz (1), A. V. Caceres (2), K. A. Agnello (2) 27409 2017-04-10 13:06:06 Surgical stabilization of concomitant canine medial patellar luxation and cranial cruciate ligament... Objectives: To compare complication rates and outcomes between cases of concomitant cranial cruciate ligament (CrCL) disease and medial patellar luxation (MPL) treated using extracapsular stabilization and tibial tuberosity transposition (ECS+TTT) and tibial tuberosity transposition and advancement (TTTA). Methods: In a multicentre retrospective study, records from four referral hospitals were reviewed for dogs with concomitant CrCL pathology and MPL treated using ECS+TTT or TTTA. Data retrieved included signalment, partial/complete CrCL tear, MPL grade, treatment performed, occurrence of postoperative complications, and postoperative outcome grade. Associations between surgical procedure and risk of complication and surgical procedure and outcome were investigated using univariable logistic regression and proportional odds logistic regression respectively. Multiple logistic regression was used to explore confounding factors. Results: A total of 72 stifles were evaluated in 66 dogs; 32 stifles were stabilized using ECS+TTT and 40 using TTTA. Overall complications were 2.7 times more frequent in the ECS+TTT group and major complications occurred only in this group. The TTTA group was less likely to suffer complications (17.5%) compared to the ECS+TTT group (46.9%) (p = 0.009) and TTTA cases had lower odds of a poorer clinical outcome (p = 0.047). Clinical significance: Stifles stabilized using ECS+TTT are more likely to suffer from postoperative complications and a poorer clinical outcome when compared to TTTA.... A. H. Fauron (1), M. Bruce (2), D. R. James (3), M. A. Owen (4), K. L. Perry (1) 27408 2017-04-10 13:05:13 Computed tomographic evaluation of femoral and tibial conformation in English Staffordshire Bull... Objective: To compare hindlimb conformation of English Staffordshire Bull Terriers with and without medial patellar luxation using computed tomography. Methods: Hindlimb computed tomography (CT) was performed on six English Staffordshire Bull Terriers with grade II or III medial patellar luxation, and six without medial patellar luxation. Inclination angle, femoral condyle trochanteric angle, anteversion angle (AA), distal anteversion angle (DAA), proximal anteversion angle (PAA), femoral varus angle (FVA), tibial valgus angle (TVA), and tibial torsion angle (TTA) were measured. Student’s T-test was conducted to compare normal limbs to limbs with medial patellar luxation, all limbs of dogs with medial patellar luxation to limbs of the control group, and medial patellar luxation affected limbs (normal limbs of unilaterally affected dogs excluded) to the control group. P-values less than 0.05 were considered significant. Results: Two dogs with medial patellar luxation were only affected unilaterally. Limbs of English Staffordshire Bull Terriers with medial patellar luxation had significantly diminished AA and DAA, in addition to decreased TVA. These differences were similar regardless of how the unaffected limbs from affected dogs were treated in our analysis. Discussion and conclusion: Medial patellar luxation in this population of English Staffordshire Bull Terriers was characterized by a decrease in femoral anteversion, external rotation of the femoral diaphysis, and decreased tibial valgus. These findings may help inform clinical decision making when performing osteotomy for treatment of medial patellar luxation in this breed.... M. Newman (1, 2), K. Voss (1, 3) 27351 2017-03-23 09:15:31 Single cycle to failure in bending of three titanium polyaxial locking plates Objective: Evaluation of the bending properties in one direction of three titanium polyaxial locking plate systems. Materials and methods: The Polyaxial Advanced Locking System (PAX®) straight plate (PAX SP), the PAX® reconstruction plate (PAX RP), and the VetLOX reconstruction plates (VetLOX) were evaluated individually and as constructs applied to a bone model simulating a fracture gap and compared using a two-way analysis of variance and Tukey post-hoc analysis. Results: The PAX SP had the highest values of bending stiffness, bending structural stiffness and bending strength. When tested as plates alone, the PAX RP and VetLOX showed no differences with regard to bending stiffness and bending structural stiffness, whilst the PAX RP had significantly higher strength. The PAX RP construct had significantly higher bending stiffness, bending structural stiffness and bending strength than the VetLOX construct. Clinical relevance: The PAX RP and VetLOX reconstruction plates are much more likely to fail when used as bridging implants, thus adjunct support is needed. The lower bending strength of the VetLOX reconstruction plates suggests it should not be used in fractures under high loads.... C. Eid (1), F. M. Martini (1, 2), A. Bonardi (1), F. Lusetti (1), A. Brandstetter de Belesini (1), G. Nicoletto (3) 27350 2017-03-23 09:14:33 Bilateral shoulder arthrodesis in a Pekinese using three-dimensional printed patient-specific... Objective: To report the use of computer-aided design software for virtual surgical planning and design of three-dimensional printed patient-specific osteotomy and reduction guides for facilitation of bilateral shoulder arthrodesis in a dog. Methods: A three-year-old male entire Pekinese was presented unable to walk due to bilateral severe medial shoulder instability. Computed tomographic data was processed to yield three-dimensional mesh representations of the humeri and scapulae which could be manipulated in computer-aided design software. Key virtual surgical planning steps included joint realignment, osteotomies of the glenoid and humeral head, and reduction. Virtual osteotomy and reduction guides were designed, three-dimensionally printed, and used intra-operatively. Results: Appropriate alignment, reduction and fixation of the humeri and scapulae were achieved bilaterally. The patient regained the ability to walk unassisted after two weeks and was subsequently able to exercise normally without lameness. Clinical significance: Patient-specific, three-dimensional printed osteotomy and reduction guides facilitated accurate bilateral shoulder arthrodeses.... B. Oxley (1) 27349 2017-03-23 09:13:49 Conformation of the proximal tibia and cranial cruciate ligament disease in small breed dogs Objectives: To investigate the conformation of the proximal tibia in small breed dogs with and without cranial cruciate ligament disease (CCLD) and to identify morphologic abnormalities that may predispose to development of CCLD. Methods: Mediolateral radiographs of the entire tibia of dogs J. Janovec (1), M. Kyllar (2), D. Midgley (1), M. Owen (3) 27348 2017-03-23 09:13:02 Cranial thoracic vertebral canal stenosis in three juvenile large-breed brachycephalic dogs treated... Objective: To describe the surgical treatment and outcome for juvenile dogs with cranial thoracic vertebral canal stenosis treated by unilateral hemilaminectomy. Study design: Case series. Animals: Three large-breed brachycephalic dogs of various breeds (Dogue de Bordeaux, Australian Bulldog, Boerboel) with neurological signs consistent with a myelopathy of the third thoracic (T) to third lumbar (L) spinal cord segment. Methods: Information on clinical presentation, diagnostic imaging, surgical procedures, postoperative complications, recovery and outcome is described. Results: Neurological signs were present and progressive for two to four weeks prior to surgery and ranged from mild ataxia to paralysis. Cranial thoracic vertebral canal stenosis was diagnosed with computed tomography imaging. Lateral and dorsolateral spinal cord compression was present at multiple sites between T2 and T6. Alternating left and right-sided compressions were common. Surgical treatment was by unilateral, continuous hemilaminectomy over three to six vertebral spaces. Postoperative morbidity was minimal and return of independent ambulation was rapid (median: 13.5 days, range: 2–29 days). Neurological status in one dog worsened four months after surgery due to reoccurrence of osseous compression; unilateral hemilaminectomy was repeated in this dog. Long-term follow-up ranged from six to 10 months; neurological signs had completely resolved in one dog and substantially improved in the other two dogs. Clinical significance: Unilateral hemilaminectomy was associated with rapid return of independent ambulation and substantial improvement in neurological scores.... A. Miller (1), A. Marchevsky (1) 27347 2017-03-23 09:12:22 Donald L. Piermattei 27335 2017-03-20 09:13:10