Veterinary and Comparative Orthopaedics and Traumatology (VCOT) Veterinary and Comparative Orthopaedics and Traumatology (VCOT) vcot de-de Tue, 07 Jul 15 11:13:46 +0200 Ahead of print: Analysis of lactate concentrations in canine synovial fluid Objective: To report synovial fluid lactate concentrations in normal and pathological canine joints. Study design: Controlled, prospective study. Methods: Lactate was measured in synovial fluid using a hand-held meter and the rest of the fluid was sent to a commercial laboratory for analysis. Samples were divided into four groups; group 1: control, group 2: osteoarthritis, group 3: immune-mediated inflammatory arthritis, and group 4: septic arthritis. Statistical analysis was performed to compare lactate concentrations between the four groups and to examine the predictive value of lactate in the diagnosis of septic arthritis. A correlation was sought between synovial fluid lactate and synovial fluid total nucleated cell count and total protein. Results: Seventy-four samples were investigated from 55 dogs. Statistical analysis found that lactate concentrations were significantly higher in the septic arthritis group than in each of the other three groups. No significant correlation could be found between synovial fluid lactate concentrations and synovial fluid total nucleated cell count or synovial fluid total protein. Lactate concentration was found to be a useful predictor of septic arthritis with a low concentration pointing towards exclusion rather than a high concentration to the diagnosis of septic arthritis. Clinical significance: Synovial fluid lactate concentration is not a good marker for osteoarthritis or immune-mediated inflammatory arthritis but it is significantly increased in septic arthritis and could help the clinician in ruling out this condition in a quick and cost-effective way.... J. L. J. Proot (1), F. de Vicente (1), D. E. Sheahan (1) 24472 2015-06-10 11:44:13 Ahead of print: Influence of two types of self-retaining retractors on multifidus muscle blood flow... Objectives: To assess the influence of the use of Gelpi and Grevel retractors on multifidus muscle blood flow during hemilaminectomy, using a dorsolateral approach, for acute disc extrusion in dogs as measured by laser speckle contrast imaging (LSCI). Methods: Blood flow in the multifidus muscles was measured intra-operatively using LSCI prior to insertion of the retractors, immediately after hemilaminectomy and removal of the retractors, and after 10 minutes of lavage of the surgical site. Plasma creatine kinase levels were measured preoperatively and 12–24 hours postoperatively. Results: Muscular blood flow was significantly decreased following retraction and remained lower than initial values 10 minutes after lavage in all dogs. The decrease in blood flow was significantly greater with Gelpi retractors (n = 8) than with Grevel retractors (n = 10). No significant relation was found between the duration of retraction and postoperative changes in creatine kinase levels or blood flow. Clinical significance: Findings in this study demonstrate a drop in blood flow within the multifidus muscles using the dorsolateral approach regardless of retractor type used. Gelpi retractors seem to have greater influence on muscular blood flow than Grevel retractors. Further studies are warranted to confirm this second finding.... D. Rohner (1), S. Forterre (1), H. Rohrbach (2), A. Bürki (3), D. Gorgas (4), J. Howard (5), F. Forterre (1) 24471 2015-06-10 11:43:19 Ahead of print: Stifle arthrodesis using a locking plate system in six dogs Objectives: To describe the use of the Fixin locking plate system for stifle arthrodesis in dogs and to retrospectively report the clinical and radiographic outcomes in six cases. Materials and methods: Medical records of dogs that had arthrodesis with the Fixin locking plate system were reviewed. For each patient, data pertaining to signalment and implant used were recorded. Plate series and thickness, number of screws placed, number of cortices engaged, and screw diameters were also recorded. The outcome was determined from clinical and radiographic follow-ups. Radiographic outcomes assessed included the measurement of the postoperative femoral-tibial angle in the sagittal plane. Results: Six dogs met the inclusion criteria for the study. Mean body weight was 13 kg (range: 3 - 34 kg). Radiographic follow-up (mean: 32 weeks, range: 3 - 52 weeks) was available for all dogs. In one case, an intra-operative complication occurred. In another case, a tibial fracture occurred 20 days after surgery. All arthrodeses healed and no implant complication was detected although all cases had mechanical lameness. Clinical significance: Stifle arthrodesis can be performed successfully using a Fixin locking plate system.... M. Petazzoni (1), T. Nicetto (2) 24470 2015-06-10 11:42:15 Ahead of print: Proximo-distal patellar position in three small dog breeds with medial patellar... Introduction: Medial patellar luxation is thought to be associated with a high proximal position of the patella in the trochlear groove. Objective: To determine whether the ratio of patellar ligament length and patellar length (L:P) is influenced by the stifle angle (75°, 96°, 113°, 130°, and 148°) in small dog breeds and to compare the L:P ratio in dogs of three small dog breeds with and without medial patellar luxation. Methods: A mediolateral radiograph of the stifle joint was used to measure the L:P ratio in the stifle joints of dogs of three small breeds with and without medial patellar luxation. The L:P ratio was evaluated at five stifle angles (75°, 96°, 113°, 130°, and 148°) in 14 cadavers (26 stifle joints) of small dog breeds in order to identify the best stifle angle to measure the L:P ratio. Then the mean ± SD L:P ratio was calculated for normal stifles and stifles with medial patellar luxation grades 1, 2, and 3 in 194 Pomeranians, 74 Chihuahuas, and 41 Toy or Standard Poodles. Results: The L:P ratio was the same for all five stifle angles in the cadavers (p = 0.195). It was also not significantly different in the three breeds (p = 0.135), in normal and medial patellar luxation-affected stifles overall (p = 0.354), and in normal and medial patellar luxation-affected joints within each breed (p = 0.19). Clinical significance: We conclude that a proximo-distal patellar position is not associated with medial patellar luxation in Pomeranians, Chihuahuas, and Toy or Standard Poodles. Thus a longer patellar ligament length does not play a role in the pathophysiology of medial patellar luxation in these small dog breeds.... C. Wangdee (1), L. F. H. Theyse (2), H. A. W. Hazewinkel (3) 24446 2015-06-03 13:15:22 Ahead of print: Ex vivo biomechanical comparison of barbed suture and standard polypropylene suture... Objectives: Evaluate performance and resistance to gap formation of a non-absorbable, barbed, monofilament suture, in comparison with a non-absorbable, smooth, monofilament polypropylene suture, in two different suture patterns: three-loop pulley (3LP) and modified Bunnell-Mayer (BM). Sample size: Seventy-two medium-sized cadaveric superficial digital flexor muscle tendon units. Methods: After manual transection and suture repair, individual specimens were placed in an electromechanical tensile testing machine and tested to monotonic failure using tensile ramp loading. Video data acquisition allowed evaluation of failure mode and quantification of gap formation. Results: Incidence of gap formation between tendon ends was significantly greater in tenorrhaphies repaired with barbed suture compared to those repaired with smooth polypropylene. Use of a 3LP suture pattern caused significantly less gapping between tendon ends when compared to the BM pattern. Conclusion: Smooth polypropylene suture was consistently superior in load performance than a unidirectional barbed suture. The 3LP pattern was more resistant than a BM pattern at preventing gap formation. Clinical significance: Smooth polypropylene should be recommended over barbed unidirectional suture for use in canine tendinous repair to provide increased resistance to gap formation. The 3LP is superior to the BM suture pattern, requiring significantly more force to cause tenorrhaphy gap formation and failure, which may translate to increased accrual of repair site strength and tendinous healing in clinical situations.... D. J. Duffy (1), R. P. Main (2, 3), G. E. Moore (4), G. J. Breur (1), R. P. Millard (1) 24445 2015-06-03 13:14:34 Ahead of print: Comparison of double locking plate constructs with single non-locking plate... Objective: To evaluate the biomechanical properties of single 3.5 mm broad dynamic compression plate (DCP) and double 3.5 mm String-of-Pearls (SOP) plate constructs in single-cycle bending and torsion. We hypothesized that the double SOP construct would outperform the broad DCP in both bending and torsional testing. Methods: Broad DCP plates and double 3.5 mm SOP plates were secured to a previously validated bone model in an effort to simulate bridging osteosynthesis. Constructs were tested in both four-point bending and torsional testing. Results: The double SOP constructs had significantly greater bending stiffness, bending strength, bending structural stiffness, and torsional stiffness when compared to the broad DCP constructs. The single broad DCP constructs had significantly higher yield torque and yield angles during torsional testing. Clinical relevance: Although the in vitro mechanical performance of the double SOP construct was significantly greater than the single broad DCP constructs under bending loads, the actual differences were small. Various patient, fracture, and implant factors must be considered when choosing an appropriate implant for fracture fixation.... K. D. Hutcheson (1), J. R. Butler (1), S. E. Elder (2) 24444 2015-06-03 13:13:45 Ahead of print: Tibial plateau levelling osteotomy in 69 small breed dogs using conically coupled... Objective: To report clinical experiences with the tibial plateau levelling osteotomy (TPLO) procedure in small breed dogs with cranial cruciate ligament (CCL) disease using specific, conically coupled, 1.9/2.5 mm locking plates and evaluating short-term complications and outcome. Methods: Medical records of small breed dogs (<15 kg) that underwent TPLO using 1.9/2.5 mm locking plates were reviewed retrospectively. The preoperative, postoperative and six to eight weeks postoperative tibial plateau angle (TPA) measurements were determined from the radiographic images. Lameness evaluation was assessed subjectively preoperatively and six to eight weeks postoperatively. Results: Sixty-nine small breed dogs (n = 79 stifles) were included in the study. Mean (± SD) preoperative TPA was 29.0 ± 3.4°, postoperative TPA was 5.8 ± 2.5°, and six to eight weeks postoperative TPA was 7.3 ± 4.1°. Sixteen complications occurred in 12 out of 79 TPLO procedures: three were intraoperative (intra-articular screw placement) and 13 were postoperative complications, of which nine were identified as minor complications not requiring surgical reintervention, and four as major complications requiring additional surgical intervention, including tibial tuberosity fracture (n = 1), osteomyelitis (n = 1), screw failure (n = 1), and plate breakage (n = 1). Lameness scores by clinical assessment reduced from a median value of 3/4 preoperatively to 1/4 at six to eight weeks postoperatively. Clinical significance: 1.9/2.5 mm locking plates appear to be a valid choice of implant for the stabilization of unilateral TPLO in small breed dogs.... G. Cosenza (1), U. Reif (1), F. M. Martini (2) 24443 2015-06-03 13:12:36 Ahead of print: Histological and immunohistological analysis of degenerative changes in the cranial... Objective: To create a canine model of excessive tibial plateau angle (eTPA) and assess the chondroid metaplasia and extracellular matrix alteration in the cranial cruciate ligament. Methods: Seven mature female Beagles were included. Cylindrical osteotomy was performed bilaterally in the proximal tibia. The TPA was increased to approximately 40° in the left tibia (eTPA stifle) and left unchanged in the right tibia (control stifle). Exercise stress was started at three months postoperatively, and at 12 months postoperatively the dogs were euthanatized and the cranial cruciate ligaments were collected. The specimens were subjected to haematoxylin and eosin staining to assess the ligamentocyte morphology and immunostaining to assess the type I (COLI), type II (COLII), and type III (COLIII) collagen, and the sry-type HMG box 9 (SOX9) staining. Results: Macroscopic cranial cruciate ligament injury was absent in six dogs but present in the eTPA stifle of one dog, which was excluded from the analysis. The ligamentocyte density decreased and the percentage of round ligamentocytes increased in the eTPA stifles. The COLII, COLIII, and SOX9 staining increased significantly and COLI deposition decreased in the eTPA stifles compared to the control stifle. Clinical significance: The extracellular matrix changed, COLI deposition decreased, and COLIII and SOX9 staining increased in the cranial cruciate ligament of the eTPA stifles. SOX9 may contribute to COLII synthesis in the extracellular matrix of the cranial cruciate ligament in eTPA stifles, and eTPA may promote chondroid metaplasia and extracellular matrix alteration.... T. Ichinohe (1), N. Kanno (1), Y. Harada (1), T. Yogo (1), M. Tagawa (1), Y. Hara (1) 24398 2015-05-22 10:42:49 Ahead of print: In vitro biomechanical testing of different configurations of acrylic external... Objective: To evaluate the in vitro biomechanical properties of four different configurations of acrylic external skeletal fixator constructs. Materials and methods: Simulated bone constructs were prepared using 2 segments of 20 mm ultra-high-density polyethylene rods with a gap of 5 mm. The full pins (1.5 mm) were passed through the proximal and distal segments of ultra-high-density polyethylene rods, in the same plane, parallel to each other in configuration U, and were crossed in the M1, M2 and C configurations at a 90° angle to each other. Configuration U was a single bilateral uniplanar construct, M1 was a double orthogonal bilateral construct, M2 was a double orthogonal bilateral construct with proximal and distal connecting articulations, and C was a double orthogonal bilateral construct with proximal and distal circumferential articulations. Temporary scaffolds of different external skeletal fixator configurations were constructed using commercially available polyvinyl chloride pipes (20 mm) connected and secured to the fixation pins at a fixed distance from the rods. Acrylic powder (polymer) mixed with liquid (monomer) was poured into the pipes and allowed to solidify to form the side bars and rings. The external skeletal fixator constructs were then subjected to axial compression, cranio-caudal three-point bending and torsion (n = 4 each) using a universal testing machine. Mechanical parameters, namely stress, strain, modulus of elasticity, stiffness and bending moment of fixator constructs, were determined from load-displacement curves. Results: Configuration U was the weakest and configuration C was the strongest under all the testing modes. Under compression,the M1, M2 and C configurations were similar. Under bending, a significant difference was observed among the uniplanar, multiplanar and circular configurations with no difference between M1 and M2. However, under torsion, all the external skeletal fixator configurations differed significantly. Clinical significance: The freeform external skeletal fixator using acrylic as a replacement for a metallic bar may be useful to treat bone fractures and luxations in small animals, as it is mechanically strong, lightweight, economical, and pins can be passed from any direction depending upon the clinical situation.... S. K. Tyagi (1), H. P. Aithal (1), P. Kinjavdekar (1), Amarpal (1), A. M. Pawde (1), T. Srivastava (1), J. Singh (1), D. N. Madhu (1) 24397 2015-05-22 10:40:48 Veterinary Orthopedic Society - 42nd Annual Conference 24353 2015-05-12 16:28:51 Promotion of Bone Regeneration K. A. Johnson 24352 2015-05-12 14:54:22 Comparison of autogenous cancellous bone grafting and extracorporeal shock wave therapy on osteotomy... Objectives: To compare optical values in the osteotomy gap created after a tibial tuberosity advancement (TTA) treated with autogenous cancellous bone graft, extracorporeal shock wave therapy, a combination of autogenous cancellous bone graft and extracorporeal shock wave therapy, and absence of both autogenous cancellous bone graft and extracorporeal shock wave therapy using densitometry. Methods: Dogs that were presented for surgical repair of a cranial cruciate ligament rupture were randomly assigned to one of four groups: TTA with autogenous cancellous bone graft (TTA-G), TTA with autogenous cancellous bone graft and extracorporeal shock wave therapy (TTA-GS), TTA with extracorporeal shock wave therapy (TTA-S), and TTA with no additional therapy (TTA-O). Mediolateral radiographs at zero, four and eight weeks after surgery were evaluated to compare healing of the osteotomy gap via densitometry. An analysis of variance was used to compare the densitometric values between groups. Results: At four weeks after surgery, a significant difference in osteotomy gap density was noted between TTA-GS (8.4 millimetres of aluminium equivalent [mmAleq]) and TTA-S (6.1 mmAleq), and between TTA-GS (8.4 mmAleq) and TTA-O (6.4 mmAleq). There were no significant differences noted between any groups at the eight week re-evaluation. Clinical significance: There were no significant differences in the osteotomy gap density at eight weeks after surgery regardless of the treatment modality used. The combination of autogenous cancellous bone graft and extracorporeal shock wave therapy may lead to increased radiographic density of the osteotomy gap in the first four weeks after surgery. Densitometry using an aluminium step wedge is a feasible method for comparison of bone density after TTA in dogs.... K. Barnes (1), O. Lanz (1), S. Werre (1), K. Clapp (1), R. Gilley (1) 24274 2015-04-22 13:11:36 Ahead of print: Distal tibial tuberosity translation using TTA implants for the treatment of patella... Introduction: Medial patellar luxation frequently occurs in dogs resulting in lameness with increasing incidence in large breed dogs. Patella alta has been defined as a patellar ligament length to patellar length ratio that is greater than two and may predispose to patellar luxation. Objective: To describe the surgical technique for stabilization of the distal translation of the tibial tuberosity using tibial tuberosity advancement plates and the clinical outcomes with follow-up for clinical cases of dogs. Methods: Dogs that were presented with the complaint of patellar luxation and that were concurrently diagnosed with patella alta and were greater than 20 kg in body weight underwent surgery using a tibial tuberosity advancement plate to stabilize the osteotomy. Radiographic assessment of A:PL (the ratio of the proximal aspect of the patella to the femoral condyle [A] to the patellar length [PL]) distance, L:P ratio (ratio of the length of the patellar ligament to the diagonal length of the patella), and owner assessment were obtained. Results: Eleven stifles in nine dogs underwent surgical correction with a mean preoperative L:P ratio of 2.47. There were no complications and the lameness resolved clinically. The mean A:PL ratios preoperatively (2.6 ± 0.22) and postoperatively (2.1 ± 0.25) were significantly different (p = 0.0003). All owners were satisfied with the outcome and all dogs had a resolution of lameness with no recurrence of patellar luxation. Clinical significance: Stabilization of distal translation of the tibial tuberosity using tibial tuberosity advancement implants to correct patella alta in large breed dogs was feasible and resulted in good clinical outcome.... L. C. Pugliese (1), F. S. Pike (2), S. W. Aiken (2) 24273 2015-04-22 12:58:01 Single-stage bilateral tibial tuberosity advancement for treatment of bilateral canine cranial... Objective: To report complications in dogs with naturally occurring cranial cruciate ligament rupture following single-stage bilateral tibial tuberosity advancement (SS-BTTA) procedures, and to compare these complications to a population of dogs undergoing unilateral tibial tuberosity advancement (UTTA). Methods: Medical records and radiographs of client-owned dogs treated with tibial tuberosity advancement between August 2008 and December 2011 were reviewed. Forty-four client-owned dogs with bilateral cranial cruciate ligament rupture that underwent SS-BTTA procedures and 82 client-owned dogs that underwent UTTA procedures were randomly selected from our hospital population. Complications were recorded and analysed. Major complications were defined as fractures or any complication requiring a second surgery. Minor complications were any problem identified that did not require surgical management. Results: Incidence for major and minor complications in the UTTA group was 2.3% and 24.4%, respectively. Incidence for major and minor complications in the SS-BTTA group was 12.5% and 26.1%, respectively. Single-stage bilateral tibial tuberosity advancement procedures had a four- to five-fold increase in odds of a major complication (p... J. E. Kiefer (1), A. Langenbach (1), J. Boim (2), S. Gordon (1), D. J. Marcellin-Little (3) 24272 2015-04-22 12:57:57 Evaluation of a distractor to increase joint space of the stifle joint in dogs: a cadaveric study Objective: To evaluate the technical feasibility and efficacy of a joint distraction technique to increase the stifle joint space and assess potential soft tissue damage due to the distraction. Methods: Twenty stifle joints of twelve canine cadavers without evidence of disease were radiographically evaluated by medio-lateral, cranio-caudal and varus-valgus stressed projections. Joint distraction was applied with loads from 40 N up to 200 N, and the joint space achieved was measured on radiographic images. Distraction plus distension with saline was subsequently applied and measured. Varus-valgus stressed projections were repeated after distraction to evaluate a potential increase in joint laxity. Results: Distraction produced a significant increase of the joint space for most of the evaluated loads. Distraction plus distension produced a significant increase for most of the loads compared to the distraction alone. No ensuing joint laxity could be inferred from the post-distraction radiographic evaluation. Clinical significance: Stifle distraction produces an increase of the joint space, which is wider when intra-articular saline is injected. This may be potentially useful for improving joint structure visualization and facilitating arthroscopic procedures, thus reducing the potential for iatrogenic damage to intra-articular structures. No soft tissue damage could be inferred by radiographic pre- and post-procedure comparison. Further clinical studies are required to evaluate potential neurovascular complications.... G. L. Rovesti (1), V. Devesa-Garcia (2), P. G. Urrutia (3), F. San Roman (2), J. Rodriguez-Quiros (2) 24271 2015-04-22 12:57:50 Reconstruction of chronic triceps tendon avulsion using synthetic mesh graft in a dog Avulsion of the triceps tendon insertion was diagnosed in a two-year-old Poodle mixed breed dog 10 weeks after traumatic injury. Diagnosis was confirmed with clinical examination and magnetic resonance imaging (MRI). The tendon was reconstructed using tension-relieving sutures augmented with a synthetic degradable porous polyurethane urea onlay mesh graft. The repair was immobilized using a transarticular external skeletal fixator with staged increases in elbow flexion. Treatment was successful, with signs of healing confirmed by MRI and normal clinical function one year after surgery. The successful outcome in this case suggests that surgical repair of a chronic triceps tendon injury using a synthetic mesh augmentation may be successful in similar cases. L. Ambrosius (1), C. Arnoldy (2), K. R. Waller III (2), J. P. Little (3), J. A. Bleedorn (2) 24191 2015-03-25 10:24:30 Radiographic and computed tomographic assessment of the development of the antebrachia and elbow... Objectives: To compare the development, monitored by radiography and computed tomography, of the antebrachia and elbow joints in seven Labrador Retrievers with healthy elbow joints and in seven Labrador Retrievers that developed medial coronoid disease (MCD), in order to determine whether disturbances in the development of the antebrachia and elbow joints, between the age of six and 17 weeks may lead to medial coronoid disease. Methods: A prospective study of 14 Labrador Retrievers in their active growth stage was performed. The development of the antebrachia and elbow joints was assessed between six and 17 weeks of age using radiography and computed tomography determining the development of secondary ossification centres, radioulnar length ratio, radial angulation, and inter-relationship between the humerus, ulna and radius. Results: For the parameters of ossification of secondary ossification centres, radioulnar length ratio, radial angulation, and joint congruence evaluation, there was no significant difference in the development of the antebrachia and elbow joints of seven Labrador Retrievers positive and seven Labrador Retrievers negative for MCD at the age of six to 17 weeks. Clinical significance: These findings demonstrate that the development of MCD in the Labrador Retrievers in our study was not related to any disturbance in the development of the antebrachia and elbow joints during the rapid growth phase.... S. F. Lau (1, 2), H. A. W. Hazewinkel (3), G. Voorhout (1) 24190 2015-03-25 10:23:09 Ahead of print: Repair of chronic rupture of the insertion of the gastrocnemius tendon in the dog... Objectives: Chronic degeneration of the gastrocnemius tendon results in scar tissue formation at the insertion of the tendon, and detachment from the calcaneus. In severe cases, excision of this tissue makes repositioning of the tendon to the calcaneus extremely difficult. A polyethylene terephthalate implant, used to aide repair by bridging gaps and allowing tissue ingrowth, was evaluated. Methods: In this retrospective study, clinical records were evaluated to assess long-term outcomes and complications. The surgical technique is also described. The implant was sutured proximally into the gastrocnemius at the myotendinous junction, and secured into the calcaneus using an interference screw. Results: The implant was used in 10 patients; of which seven returned to full function. Major complications, due to infection, were identified in two of the 10 patients. Minor complications occurred in five of the 10 patients. These were associated with external coaptation in three of the patients in the immediate postoperative period. One minor infection was reported. These all resolved without further complication. Long-term outcome was available in eight patients, with six of these eight dogs returning to normal exercise. Clinical significance: This implant may be suitable for use in canine patients with severe gastrocnemius tendon degeneration. Ongoing evaluation is warranted.... M. A. Morton (1), D. G. Thomson (1), R. M. Rayward (1, 2), M. Jiménez-Peláez (1), R. G. Whitelock (1) 24189 2015-03-25 10:21:45 A comparison of anatomical lateral distal femoral angles obtained with four femoral axis methods in... Objectives: To report the repeatability and reproducibility of four different anatomical proximal femoral axis (a-PFA) methods for measuring anatomical lateral distal femoral angle (a-LDFA), and to compare a-LDFA values produced by each method at three different femoral elevation angles. Methods: Digital radiographs were obtained of seven dry canine femora at 0°, 12.5° and 25° elevations. Using image analysis software, landmarks defining four different a-PFA and the condylar axis were identified by two independent observers on two separate occasions. Corresponding a-LDFA were calculated for each femur, elevation and a-PFA. Repeatability and reproducibility parameters were calculated and compared statistically, along with the effect of technique and elevation on a-LDFA value. Results: Interobserver repeatability coefficients were subjectively better for three of the a-PFA methods at 2° compared to the fourth at 3.1°. Median a-LDFA increased significantly (p ≤0.002) with increasing femoral elevation for all a-PFA methods, with a median increase of 3.3°. The median difference in a-LDFA between a-PFA methods yielding the highest and lowest measurements was 2.6° over all three elevations. Clinical significance: The combined effects of a-PFA choice, femoral elevation and measurement reproducibility may produce typical errors of ± 2.6°, which could have implications for the selection of candidates for corrective osteotomies. Clinicians need to be aware that values obtained with one method and femoral elevation may not be equivalent to values obtained with other methods or elevations.... J. E. Miles (1), M. Mortensen (1), E. L. Svalastoga (1), T. Eriksen (1) 24188 2015-03-25 10:20:44 Treatment of a diaphyseal long-bone defect with autologous bone grafts and platelet-rich plasma in a... Introduction: Large bone defects are a therapeutic challenge to surgeons and are often associated with a high morbidity. The use of autologous cancellous bone graft represents an essential therapeutic option and is considered the gold standard. However, the use of platelet-rich plasma (PRP) for improving bone defect healing has been discussed controversially. The aim of this study was to evaluate the treatment of a diaphyseal long-bone defect in a rabbit model with a combination of PRP and autologous cancellous bone. Material and methods: A monocortical long-bone defect in the radial diaphysis of 24 New Zealand white rabbits was filled either with autologous cancellous graft as a control group or with autologous cancellous graft combined with autologous PRP. Histomorphometrical and radiological analysis as well as quantification of platelets and growth factors were performed. The animals were euthanatized after three and six weeks according to the study arms. Results: A significant improvement in bone healing was observed histomorphometrically in the PRP group in the central area of the defect zone (p <0.01) as well as the cortical defect zone (p <0.01). The radiological findings were in accordance with the histomorphometrical results. Comparing native blood and PRP, an enrichment of growth factors and platelets was detectable in the PRP. Conclusion: Within this animal study, the combination of PRP and autologous cancellous bone grafts improved bone healing significantly compared to the sole application of autologous bone. Therefore, further efforts should be initiated to establish the composite of PRP and autologous bone for bone healing disorders in clinical use.... J. Schneppendahl (1), P. Jungbluth (1), T. T. Lögters (1), M. Sager (2), M. Wild (1), M. Hakimi (1), J. Windolf (1), J. P. Grassmann (1) 24187 2015-03-25 10:19:37 Effect of locally injected autologous platelet-rich plasma on second intention wound healing of... Objectives: Second intention wound healing may be impaired by wound and host factors and thus more advanced therapies are required for a fast and satisfactory outcome. Platelet-rich plasma (PRP), rich in growth factors and cytokines essential for tissue repair, could improve wound healing. The purpose of this experimental study was to evaluate the effect of locally injected autologous PRP on second intention healing of acute full-thickness skin defects in dogs. Methods: Three 2x2 cm full-thickness skin defects were created bilaterally on the dorsolateral area of the trunk of six Beagle dogs. The wounds of one randomly selected side received PRP treatment, whereas the contralateral wounds were left untreated (controls). Wound healing was evaluated by planimetry, laser-Doppler flowmetry measurements of tissue perfusion, and histologically. Results: The rate of wound healing did not differ significantly between the two groups. Tissue perfusion was significantly higher in the PRP-treated group (p = 0.008) compared to controls on day 10. Histological evaluation revealed a trend towards greater collagen production and a significantly better collagen orientation (p = 0.019) in PRP-treated wounds on day 20. Clinical significance: Locally injected autologous PRP does not accelerate the healing process, but increases tissue perfusion and may promote the formation of organized collagen bundles in acute full-thickness skin defects in dogs.... M. Karayannopoulou (1), D. Psalla (2), G. Kazakos (1), P. Loukopoulos (2), N. Giannakas (1), I. Savvas (1), M. Kritsepi-Konstantinou (3), A. Chantes (4), L. G. Papazoglou (1) 24186 2015-03-25 10:17:26 Veterinary Orthopedic Society - 42nd Annual Conference 24151 2015-03-17 10:11:57 Prior Publication of Papers K. A. Johnson 24150 2015-03-17 09:33:09 Perioperative risk factors for surgical site infection in tibial tuberosity advancement: 224 stifles Objective: To examine perioperative factors affecting surgical site infection (SSI) rate following tibial tuberosity advancement (TTA). Study design: Retrospective case series. Sample population: 224 stifles in 186 dogs. Methods: Medical records of dogs that underwent TTA in a single institution were reviewed. Information on signalment, anaesthetic and surgical parameters, as well as occurrence of SSI was recorded. Dogs were followed for a minimum of three months postoperatively. The association between perioperative factors and SSI was assessed using Chi-squared tests and binary logistic regression. Results: The prevalence of SSI was 5.3% (12/224 TTA). Surgical time (p = 0.02) and anaesthesia time (p = 0.03) were significantly associated with SSI. For every minute increase in surgical time and anaesthesia time, the likelihood of developing SSI increased by seven percent and four percent respectively. The use of postoperative antimicrobial therapy was not significantly associated with lower SSI (p = 0.719). Implants were removed in 1.3% of cases (3/224 TTA). Conclusions: The findings of this study suggest that increased surgical and anaesthesia times are significant risk factors for SSI in TTA, and that there is no evidence that postoperative prophylactic antimicrobial therapy is associated with SSI rate.... F. W. Yap (1), I. Calvo (1), K. D. Smith (1), T. Parkin (1) 24115 2015-03-11 08:39:35 Evaluation of the diagnostic accuracy of four-view radiography and conventional computed tomography... Objective: The purpose of our study was (1) to determine whether four-view radiography of the pelvis is as reliable and accurate as computed tomography (CT) in diagnosing sacral and pelvic fractures, in addition to coxofemoral and sacroiliac joint subluxation or luxation, and (2) to evaluate the effect of the amount of training in reading diagnostic imaging studies on the accuracy of diagnosing sacral and pelvic fractures in dogs. Methods: Sacral and pelvic fractures were created in 11 canine cadavers using a lateral impactor. In all cadavers, frog-legged ventro-dorsal, lateral, right and left ventro-45°-medial to dorsolateral oblique frog leg (“rollover 45-degree view”) radiographs and a CT of the pelvis were obtained. Two radiologists, two surgeons and two veterinary students classified fractures using a confidence scale and noted the duration of evaluation for each imaging modality and case. The imaging results were compared to gross dissection. Results: All evaluators required significantly more time to analyse CT images compared to radiographic images. Sacral and pelvic fractures, specifically those of the sacral body, ischiatic table, and the pubic bone, were more accurately diagnosed using CT compared to radiography. Fractures of the acetabulum and iliac body were diagnosed with similar accuracy (at least 86%) using either modality. Clinical significance: Computed tomography is a better method for detecting canine sacral and some pelvic fractures compared to radiography. Computed tomography provided an accuracy of close to 100% in persons trained in evaluating CT images.... S. M. Stieger-Vanegas (1), S. K. J. Senthirajah (1), S. Nemanic (1), W. Baltzer (1), J. Warnock (1), G. Bobe (2, 3) 24114 2015-03-11 08:38:55