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Objective: To biomechanically evaluate the stability of internal fixation methods for femoral neck fractures in small-breed dogs. Furthermore, the possibility of replacing the headed screw with fully threaded headless cannulated screws in the fixation method was assessed., Methods: The study was conducted from December 12, 2023, to February 7, 2024. A total of 18 femurs from 9 canine cadavers were used in this study. After a simple neck fracture was created, in group A (n = 6), the fracture was stabilized with three 1.1-mm parallel Kirschner wires (K-wires). In group B (n = 6), a 3.0-mm partially threaded cannulated screw and an antirotation pin were used. In group C (n = 6), a 2.5-mm fully threaded headless cannulated screw and an antirotation pin were used. A mechanical test was conducted to apply a single axial compressive load to the femoral head., Results: 9 adult small-breed dogs weighing 3.6 to 8.3 kg (mean ± SD; 5.9 ± 1.6). The mean maximum failure load was highest in group C (495 ± 81 N), followed by group B (454 ± 50.4 N), and then group A (222 ± 21.6 N). Significant differences in maximum failure load were observed between groups A and B as well as groups A and C but not between groups B and C., Conclusion: The use of fully threaded headless cannulated screws presents a promising method for internal fixation of canine femoral neck fractures., Clinical Relevance: To demonstrate the potential stability and reliability of fully threaded headless cannulated screws.

Objective: To report the surgical approaches and stabilization of lateral and medial tibial plateau fractures (TPF), as well as the long-term outcome following repair., Study Design: Prospective series of three client-owned dogs., Animals: Three dogs., Methods: For the two lateral TPF cases (Unger type 41-B1), the surgical approach included separation of the lateral collateral ligament and long digital extensor tendon. The lateral meniscus was elevated to allow visualization of the tibial surface and assess fracture reduction. The first case was repaired using two 2.0 mm lag screws (with washers). The second case sustained a lateral TPF, fibular fracture and concurrent tubercle of Gerdy fracture. Both tibial fractures were stabilized using two 2.0 mm lag screws with washers and two 0.9 mm Kirschner wires (K-wires). A third case, diagnosed with an Unger type 41-B2 medial TPF, was treated using 0.9 mm K-wires and 22-gauge tension band., Results: There were no major complications noted. One minor complication occurred (screw yield two weeks postoperatively). By 8 weeks, all patients reached clinical union with good limb function. Owners were contacted 9-36 months postoperatively. LOAD scores and examinations were performed for two of three patients; the third patient was not contactable after relocating out of state. Both cases with completed questionnaires had a LOAD score of 5/52., Conclusion: Tibial plateau fractures are rare in canine patients. While challenging, they can be successfully managed using a combination of lag screws, K-wires, and tension band., Clinical Significance: Surgical stabilization of TPF is feasible and may reduce the risk of meniscal injury., (© 2024 The Authors. Veterinary Surgery published by Wiley Periodicals LLC on behalf of American College of Veterinary Surgeons.)

Objective: To describe the successful surgical management of a previously unreported Salter-Harris type I fracture of the accessory carpal bone in a dog., Animal: An 11-week-old intact female Golden Retriever-Poodle cross presented with a history of a marked left forelimb lameness following a suspected fall from a height., Clinical Presentation, Progression, and Procedures: On physical examination, the patient demonstrated a severe left forelimb lameness and pain on palpation and range of motion of the left carpus. Orthogonal radiographs of the distal left forelimb demonstrated a type I Salter-Harris fracture of the accessory carpal bone with proximal displacement of the palmar fragment., Treatment and Outcome: The patient underwent open reduction and internal fixation wherein the fracture was reduced and stabilized with two 1.1-mm Kirschner wires. Postoperatively, the patient was initially managed with a carpal flexion bandage for 2 weeks and then a soft padded bandage was maintained until 4 weeks postoperatively. The patient recovered well and was walking and weight-bearing comfortably following removal of the carpal flexion bandage. Repeat radiographs performed 4 and 8 weeks postoperatively demonstrated adequate fracture healing but showed mild proximocaudal implant displacement. Implant removal was not performed, as the patient was doing well at home and the implant migration appeared static and was not causing clinical morbidity., Clinical Relevance: To the authors' knowledge, this was the only reported case of a Salter-Harris fracture of the accessory carpal bone in a dog and the only described case of successful surgical stabilization.

Objective: The objective of this study is to compare drilling variables and torsional mechanical properties of rabbit femora after bicortical drilling with a 1.5-mm standard surgical drill bit, acrylic drill bit, and K-wire., Samples: 24 pairs of rabbit femora., Methods: After drilling under controlled axial displacement rate, each bone was biaxially loaded in compression followed by rapid external torsion to failure. Maximum axial thrust force, maximum drill torque, integral of force and displacement, change in temperature, maximum power spectral density of the torque signal, torque vibration, and torque and angle at the yield and failure points were collected. Pre- and postyield stiffness, yield and failure energies, and postyield energy were calculated., Results: The work required to drill through the cis- and transcortices (integral of force and displacement) was greater for the K-wire, followed by the acrylic and then standard drill bits, respectively. The K-wire demonstrated higher maximum torque than the drill bits at the ciscortex, and the force of drilling was significantly greater. The vibration data was greater with the acrylic and standard drill bits than the K-wire. There was no difference in torsional strength between drilling types., Clinical Relevance: Mechanical differences exist between different drill bits and K-wire and demonstrate that the K-wire is overall more damaging than the surgical drill bit.

Objective: To compare the mechanical properties of suture tape and orthopedic wire cerclage in an ex vivo canine median sternotomy model., Study Design: Ex vivo., Animals: Twelve large-breed canine cadaveric sternums., Methods: Median sternotomies were performed, leaving the manubrium intact. The specimens were randomly assigned to group W (20-gauge stainless steel orthopedic wire cerclage in a figure-of-eight pattern) or group ST (suture tape in a figure-of-eight pattern). Each specimen was laterally distracted until failure using an electrodynamic materials-testing system., Results: No differences were observed for displacement, yield load, maximum load, implant failure between the groups. The orthopedic wire construct was stiffer than the suture tape construct., Conclusion: Suture tape was biomechanically similar to orthopedic wire cerclage for sternotomy closure in dogs, although wire constructs were stiffer., Clinical Significance: Suture tape may represent an alternative to cerclage wire for sternotomy closure in dogs. Additional studies evaluating its clinical use are needed., (© 2023 American College of Veterinary Surgeons.)

Objective: To evaluate the ease and accuracy of using a 3-D printed (3-DP) drill guide to insert Kirschner wires through the ilium and into the sacral body in preparation for minimally invasive iliosacral screw placement in dog cadavers., Animals: 10 dog cadavers weighing 20 to 30 kg (mean ± SD, 24.5 ± 5 kg)., Methods: Kirschner wires were placed using a limited approach to the lateral ilium. Fluoroscopy was used in freehand and 3-DP drill guide application groups to facilitate the placement of a 1.0-mm Kirschner wire that was over-drilled using a 2.5-mm cannulated drill bit. Kirschner wires were placed using a 3-DP drill guide on 1 hemipelvis and freehand wire placement was done on the contralateral hemipelvis. Postprocedural CTs were obtained, and 2-D and 3-D analyses were performed. The Student t-test and Wilcoxon rank sum test were used to compare groups. A Pearson correlation coefficient was performed to evaluate the in-group correlation., Results: Likert scores that assessed the ease of the procedure were significantly greater (P = .04) and the incision length was significantly shorter (P = .016) in the 3-DP drill guide group compared with the freehand group. The time of the procedure, the number of attempts to obtain accurate Kirschner wire placement, and fluoroscopy images did not differ (P > .05) between application groups. Drill tracks were primarily confined to the sacral body, with minor projected screw thread cortical breeches occurred in 1 cadaver in the freehand group and 2 cadavers in the 3-DP drill guide group., Clinical Relevance: The 3-DP drill guide simplified appropriate iliosacral Kirschner wire placement through a smaller incision compared with freehand drilling and would appear to be an efficient, practical instrument to facilitate accurate fluoroscopic-assisted screw placement when stabilizing sacroiliac luxations in dogs.

Objectives: This study aimed to compare the biomechanical properties of three stabilisation techniques in feline patella transverse fractures and select the strongest method with potentially minimal complications., Methods: Patella fracture was simulated in 27 feline cadaveric pelvic limbs (mean weight of the cadavers 3.78 kg), and the limbs were randomly grouped to be stabilised with one of the three stabilisation methods. The modified tension band wiring technique with a single Kirschner wire (0.9 mm) and figure-of-eight wiring (20 G) was applied to group 1 (n = 9). Group 2 (n = 9) was stabilised with a combination of circumferential and figure-of-eight wiring techniques with orthopaedic wire (20 G). Group 3 (n = 9) was stabilised with the same technique as group 2, but with #2 FiberWire. The knee joints were positioned and fixed in the neutral standing angle (135°) and tested by applying tensile force. The loads at gap formations of 1, 2 and 3 mm were recorded, and the maximum failure load was measured in each group., Results: In all the loads at displacement (1, 2 and 3 mm), group 3 was significantly stronger than groups 1 and 2, respectively ( P <0.017). Group 3 (261.0 ± 52.8 N) showed significantly stronger fixation in the maximum load compared with group 1 (172.9 ± 45.6 N) ( P <0.017). No significant difference was observed between groups 1 and 2 (204.9 ± 68.4 N) or between groups 2 and 3., Conclusions and Relevance: This study shows that the combination of circumferential and figure-of-eight techniques with FiberWire is more resistant to displacement than metal wire in this ex vivo feline patella fracture model.

This report describes the combination of two surgical fracture repair techniques and the postoperative management of a mandibular diastemal fracture in a two-year-old mare. The mare was referred to a veterinary hospital with a laceration over the body of the right mandible. Radiographic assessment revealed two mesial fracture lines involving the second premolar tooth and a ventrally displaced bone fragment. The mare was treated under general anesthesia and the fracture was corrected using open reduction and plate fixation. A 3.5 mm narrow 15-hole locking compression plate with seven locking screws were used in a bridge form. Cerclage wire was also used to anchor the incisor teeth to the second and third premolar teeth. The cerclage wire and incisor teeth were covered with polymethylmethacrylate to prevent implant failure and avoid injury to the oral mucosa. Implants were removed 55 days after surgery and the mare was discharged from hospital five days later. The mare returned for cerclage wire removal after 90 days and was allowed to resume exercise thereafter. The combination of two surgical techniques, proper implant choice and appropriate postoperative management, including use of pelleted feed, contributed to successful bone healing and return to function.

Objective: To determine the effect of Kirschner wire (K-wire) grip location on bend angle, bend radius, and torque when performing a Z-bend technique., Study Design: Experimental study., Sample Population: Ten samples at each of five grip locations for each of three K-wire diameters., Methods: K-wires of three diameters (0.9, 1.1, 1.6 mm) were drilled into PVC pipe, and a Jacob's chuck was used to bend the wires at five periodic grip locations (distance from the bone model). Torque, bend angle, and bend radius were determined for each sample. Outcome variables were statistically analyzed by grip location to determine significant relationships., Results: A grip location of 2.0 cm in the 0.9 mm K-wire group minimized bend angle (mean ± SD: 75.92° ± 0.81) and bend radius (2.89 mm ± 0.08). A grip location of 3.0 cm in the 1.1 mm K-wire group minimized bend angle (72.88° ± 0.98) and bend radius (2.47 mm ± 0.20). A grip location of 3.0 cm minimized bend angle (74.38° ± 1.93) and bend radius (2.71 mm ± 0.27) in the 1.6 mm K-wire group. Torque at these grip locations for the 0.9, 1.1, and 1.6 mm K-wires was 6.50 N-m ± 0.0, 11.00 N-m ± 0.0, and 19.05 N-m ± 0.16, respectively., Conclusion: Bend angle and bend radius can be minimized by bending K-wires at specific grip locations, though torque is not minimized at these locations. Clinical significance These findings provide an evidence-based recommendation of where surgeons should grip K-wires when bending them., (© 2022 American College of Veterinary Surgeons.)

Background: To investigate the incidence of implant-related complications when humeral unicondylar fractures in immature dogs are stabilised with a transcondylar bone screw and epicondylar Kirschner wire (K-wire)/pin., Methods: Records of cases treated by the author in this clinic over a 10-year period were screened for those involving humeral condylar fractures. These were then reduced to include those patients who were less than 7 months of age with unicondylar fractures and follow-up radiographs., Results: Thirty fractures in 29 dogs met the inclusion criteria. All of these had been stabilised with a transcondylar bone screw and epicondylar K-wire. Fracture healing was documented in all dogs. Surgical site infection was not recorded. Implant-related major complications were reported in four (13%) dogs and successfully treated by either implant removal or replacement. Short-term outcome was judged as excellent in 23 out of 30 and good in seven out of 30 of these fractures., Conclusion: The use of a transcondylar bone screw in combination with an epicondylar K-wire is an appropriate fixation method for humeral unicondylar fractures seen in puppies less than 7 months of age., (© 2022 British Veterinary Association.)

Objective: To determine and compare median sternotomy (MS) closure-related complication rates using orthopedic wire or suture in dogs., Study Design: Multi-institutional, retrospective observational study with treatment effect analysis., Animals: 331 client-owned dogs, of which 68 were excluded., Methods: Medical records of dogs with MS were examined across nine referral centers (2004-2020). Signalment, weight, clinical presentation, surgical details, complications, and outcomes were recorded. Follow-up was performed using patient records and email/telephone contact. Descriptive statistics, treatment effect analysis and logistic regression were performed., Results: Median sternotomy closure was performed with wire in 115 dogs and suture in 148. Thirty-seven dogs experienced closure-related complications (14.1%), 20 in the wire group and 17 in the suture group. Twenty-three were listed as mild, four as moderate and 10 as severe. Treatment effect analysis showed a mean of 2.3% reduction in closure-related complications associated with using suture versus wire (95% CI: -9.1% to +4.5%). In multivariable logistic regression, the only factor associated with increased risk of closure-related complications was dog size (p = .01). This effect was not modified by the type of closure used (interaction term: OR = 0.99 [95% CI: 0.96/1.01])., Conclusion: The incidence of closure-related complication after MS was low compared to previous reports. The likelihood of developing a closure-related complication was equivalent between sutures and wires, independent of dog size, despite a higher proportion of complications seen in larger dogs (≥20 kg)., Clinical Significance: Use of either orthopedic wire or suture appear to be an appropriate closure method for sternotomy in dogs of any size., (© 2022 The Authors. Veterinary Surgery published by Wiley Periodicals LLC on behalf of American College of Veterinary Surgeons.)

Objectives: The aim of this study was to describe the demography, aetiology, location and classification of physeal fractures in cats, and to describe their management and outcomes., Methods: Clinical records and radiographs of cats referred for management of physeal fractures were retrospectively reviewed. Fractures of the proximal femoral physis were excluded. Descriptive statistics were used to describe signalment, cause of injury, presence of concurrent injuries, fracture description, treatment modality, complications, follow-up, physeal closure, implant removal and outcome., Results: Thirty-four cats with 36 fractures were included, of which 17 affected the distal femur, 11 the distal tibia and fibula, five the distal radius and ulna, two the proximal tibia and one the distal humerus. Salter-Harris classification was type I in 14, type II in 16, type III in two and type IV in four fractures. Thirty-four fractures were treated with primary fixation, and the most common method was crossed Kirschner wires (24/34 fractures). Complications were observed in 14 fractures, of which 12 were minor. At radiographic follow-up, physeal closure was reported in 23 fractures, of which 15 were considered premature. Implant removal was performed in three fractures. Outcome was good in 28, fair in four and poor in two fractures., Conclusions and Relevance: Fracture of the distal femoral physis was the most common physeal fracture seen. Cats presenting with physeal fractures may be skeletally immature or mature with delayed physeal closure. The rate of physeal closure after fracture repair was relatively high but without apparent impact. The frequency of implant removal was very low, indicating that despite having a physeal fracture repair, most cats did not require a second procedure to remove implants. Overall, internal fixation provided a good outcome in most fractures.

Objective: To compare the mechanical performance of cerclage secured with twist, single-loop, and double-loop knots subjected to cyclic loading., Study Design: In vitro biomechanical study., Sample Population: Twist, single-loop and double-loop cerclage configurations of 1.0 mm wire., Methods: The peak load resisted by each cerclage type was determined (n = 6). Cerclage were loaded cyclically to 80%, 60%, 40%, or 20% of its peak load (n = 8 per load level). The number of cycles until each cerclage loosened (residual tension <10 N) was recorded., Results: All wires that failed did so by loosening. Twist cerclage cycled to 390 N and 290 N loosened within the first 10 cycles, and, when cycled to 100 N, they loosened by 250 cycles. All twist knots loosened by untwisting. Single-loop cerclage cycled to 320 N loosened within 10 cycles. At 240 N, 5 single-loop cerclage resisted 250 cycles before loosening. At 160 N, 2 of the 8 single-loop cerclage did not loosen by 100 000 cycles. When cycled to 640 N, one of the double-loop cerclage did not loosen following 500 000 cycles. When cycled to 480 N, 3 of the 8 wires did not loosen., Conclusion: Double-loop cerclage will be tighter and are better able to resist cycling than twist or single-loop cerclage., Clinical Significance: Use of double-loop cerclage to stabilize bone fragments or prevent fissure propagation can be expected to provide greater resistance to loosening than twist or single-loop cerclage, both initially and with repeated loading., (© 2021 American College of Veterinary Surgeons.)

Objective:  The aim of this study was to compare the biomechanical properties of a hybrid external skeletal fixator (HESF) construct to the placement of paired interfragmentary Kirschner wires alone, and pin and tension band wire (PTBW) fixation for the stabilization of simulated tibial tuberosity fractures in dogs., Study Design:  Tibias were harvested from 12 skeletally mature dog cadavers weighing 20 to 30 kg. An osteotomy was made through the base of the tibial tuberosity, which was subsequently repaired with either paired Kirschner wires, PTBW fixation or a HESF. A tensile load was applied to the tibial tuberosity until failure occurred. Mode of failure was described and biomechanical parameters obtained were compared between fixation groups., Results:  The PTBW fixation and HESF construct afforded greater stiffness and load at 3 mm of axial displacement compared with fixation with Kirschner wires alone. There was no significant difference in stiffness and load at 3 mm displacement between PTBW and HESF fixation. Failure occurred by bending and pullout of the Kirschner wires for all fixation groups, preceded by untwisting of the knot in PTBW specimens., Conclusion:  The HESF may provide a favourable alternative to PTBW fixation for tibial tuberosity avulsion fracture stabilization in dogs with substantial remaining growth potential., Competing Interests: None declared., (Thieme. All rights reserved.)

Objective: To report the radiographic, surgical and postoperative features in horses with unstable oblique mandibular fractures secured with polyaxial pedicle screws (PPS) external fixation construct and intraoral wiring., Animals: Three client-owned horses., Study Design: Short case series., Methods: Two horses each had a unilateral fracture, which did not improve after conservative management, and one horse had bilateral fractures. Clinical and radiographic features were documented. Polyaxial pedicle screw external fixators and intraoral tension band wiring were applied in standing horses after combining sedation and regional nerve anesthesia. Intraoral wires were implanted through a lateral buccotomy between teeth (two horses) or burred through exposed crown (one horse) and then secured around the incisors. The PPS were inserted under radiographic guidance to avoid tooth roots. Healing was assessed with radiographic examination. The PPS external fixator rod and intraoral wires were removed first. The mandible was manipulated, and, if it was stable, the PPS were removed., Results: Implants were removed at 6, 8, or 10 weeks after the mandibles were palpably stable. Complications included broken wires in one horse, bone sequestration in one horse, and infection in one horse. Follow-up communication with the owners 12 to 18 months later confirmed complete healing without further complications of the fractured mandibles or teeth., Conclusion: Polyaxial pedicle screw external fixation led to fracture healing and a return to function in all three horses. The complications encountered did not preclude a successful outcome., Clinical Significance: Polyaxial pedicle screw external fixation coupled with intraoral wiring provides an alternative to treat unstable equine mandibular fractures without general anesthesia., (© 2021 The American College of Veterinary Surgeons.)

Background: Mandibular fractures are common in camels, leading to considerable economic losses. This study explored methods of improving mandibular fractures repair, adjuvant with interdental wire, or bone plate fixation. Autologous bone marrow (BM) injection enhances osteogenesis and rapid healing., Objectives: To investigate the effect of autologous BM aspirate as an adjuvant treatment for repairing mandibular fractures in camels with interdental wire, or bone plate fixation., Methods: Thirty dromedary camels aged 5-8 years and of both sexes were randomly divided into 4 treatment groups: group 1 (n = 10) treated with stainless steel wire fixation and BM injection at the fracture line, group 2 (n = 10) treated with plate fixation and BM injection at the fracture line, group 3 (n = 5) treated with stainless steel bone wire fixation and placebo saline injection at the fracture line, and group 4 (n = 5) treated with plate fixation and placebo injection at the fracture line. The mandibular fractures were followed weekly for 12 weeks postoperatively to assess improvement and healing based on clinical evaluation, radiographic union scale, and bone turnover markers (i.e., bone alkaline phosphatase, osteocalcin, pyridinoline, and deoxypyridinoline)., Results: Compared to other groups, elevated bone turnover markers in group 1 were demonstrated ( p < 0.05) on the seventh postoperative day. Likewise, compared to other groups, both clinical findings and radiographic union scale significantly improved ( p < 0.05) in group 1 on the 56th postoperative day., Conclusions: BM aspirate has a promising beneficial osteogenic effect on mandibular fracture repair in camels, most notably when combined with interdental wire fixation., Competing Interests: The authors declare no conflicts of interest., (© 2020 The Korean Society of Veterinary Science.)

Objective: To determine the influence of wiring configurations on initial tension and resistance to tensile loads in tension band constructs without the contributions of Kirschner-wire stabilization., Study Design: Experimental study., Sample Population: A solid brass femur model manufactured on the basis of computed tomography of a normal right femur of a 30-kg dog modified by transection of the greater trochanter and placement of two pins that did not cross the simulated osteotomy., Methods: Four tension band configurations were applied to the metal trochanteric osteotomy model: figure-of-eight with one twist (OT), figure-of-eight with two twists (TT), dual interlocking single loop, and double loop (DL). Configurations were tested under both monotonic loading (n = 8 per configuration) and incremental cyclic loading (n = 8 per configuration). Initial tension after tying, residual tension remaining after each cycle, and failure load at 2 mm of displacement (considered equivalent to clinical failure) were compared between configurations., Results: The initial tension and the load to 2 mm of displacement were lower for OT wires compared with TT wires. The DL was the strongest and most stable configuration, generating 2.3 to 3.5 times greater initial tension, maintaining a greater percentage of residual tension under incremental cyclic loads, and resisting 2.0 to 2.4 times greater load before failure at 2 mm. Failure load was highly correlated with initial tension., Conclusion: Wire configurations reaching greater initial tension, such as the DL, allowed constructs to resist higher tensile loads., Clinical Impact: Wire configurations allowing higher initial tension may be warranted when tension bands are expected to sustain high tensile loads., (© 2019 The American College of Veterinary Surgeons.)

Objective:  The aim of this article was to report the surgical technique and clinical outcome of a modified cross-pin technique for the treatment of distal tibial physeal fractures in cats without postoperative external coaptation., Study Design:  This study was a retrospective clinical study., Animals:  A total of 9 cats were presented with fracture of the distal tibial physis., Materials and Methods:  Medical records from July 2014 to September 2018 were reviewed. In all cases, a second medial and a craniolateral Kirschner wires were added to the traditional cross-pin technique. Information reviewed included orthogonal radiographs pre- and post-surgery and at subsequent re-examinations, subjective assessment of lameness and passive range of motion, veterinary clinical assessment and completion of a functional questionnaire (feline musculoskeletal pain index) at the time of writing this report. Eight owners completed the questionnaire. The mean questionnaire follow-up time was 12.7 months., Results:  Uncomplicated fracture healing occurred in all patients. Two patients required implant removal due to Kirschner wire migration and protrusion through the skin at 5 and 12 months post-surgery. No other complications were noticed. Eight patients had an excellent outcome, and one patient had a good outcome., Conclusion:  Distal tibial physeal fractures in cats can be treated successfully with the use of a modified cross-pin technique and without the use of external coaptation. Prognosis should be considered favourable for this type of fracture., Competing Interests: None declared., (Georg Thieme Verlag KG Stuttgart · New York.)

Objective:  The main aim of this study was to describe complications in dogs weighing < 20 kg treated for medial patellar luxation and to determine risk factors associated with these complications., Materials and Methods:  Medical records were reviewed and cases were grouped based on four techniques of stabilization for the tibial tuberosity transposition (TTT). Variables including animal signalment, clinical presentation, TTT technique, other concurrent surgical techniques and associated complications were investigated. Multiple logistic regression was used to determine the association of the same variables with specific complications such as tibial tuberosity fractures or avulsions, patellar reluxation and implant-related complications., Results:  Of the 100 procedures performed, 37 suffered a complication. There were no significant differences in the overall complication rate between TTT stabilization techniques. Preservation of the tibial tuberosity distal cortical attachment was associated with a reduced risk of implant-related complications, whereas adding a medial release to the surgical techniques was associated with an increased risk of medial patellar reluxation. The type of trochleoplasty performed did not affect the complication rate., Conclusions:  In the current study, a high rate of complications was found in dogs < 20 kg undergoing medial patellar luxation surgery. Performing a medial release and preserving the distal cortical attachment of the tibial tuberosity were the only variables associated respectively with an increase and a reduction in the risk of postsurgical complications., Competing Interests: Dr. GERMAN reports grants, personal fees, non-financial support and other from ROYAL CANIN/MARS PETCARE, other from RAW FEEDING VET SOCIETY, non-financial support and other from PURINA, personal fees and non-financial support from SCIVAC, non-financial support and other from NORDIC PETFOOD CONFERENCE, personal fees, non-financial support and other from AAFP CONFERENCE, personal fees, non-financial support and other from AUSTRIAN ASSOC SMALL ANIMAL PRACT, personal fees and non-financial support from ICVC MEETING, personal fees and non-financial support from VMX CONFERENCE, personal fees and non-financial support from LONDON VET SHOW, non-financial support and other from ECVIM, non-financial support and other from BSAVA, non-financial support from CABI SYMPOSIUM, personal fees, non-financial support and other from UNIVERSITY OF CAMBRIDGE, non-financial support and other from WSAVA, personal fees, non-financial support and other from EEVC CONGRESS, personal fees, non-financial support and other from ISFM/ICC, personal fees, non-financial support and other from SLOVAKIAN VET CONGRESS, rants from ZOETIS, outside the submitted work. His academic post at the University of Liverpool is financially supported by Royal Canin. Other authors do not have any affiliation, financial support or conflict of interest with the technique or products used., (Georg Thieme Verlag KG Stuttgart · New York.)

Objective: To describe a minimally invasive surgical technique for the treatment of comminuted humeral bicondylar (also known as T-Y) fractures in dogs and report outcome in 3 cases., Study Design: Surgical technique description and case report., Animals: Three consecutive dogs with traumatic comminuted humeral T-Y fractures., Methods: Dogs that presented with a traumatic humeral T-Y fracture were prospectively included. The condylar component of the fractures was reduced first by using a combination of percutaneous forceps and K-wires. A transcondylar screw was applied, and epicondylar pins were preplaced medially and laterally. The metaphyseal component of the fracture was then reduced and stabilized with the pins. Finally, a bone plate was applied percutaneously along the medial humeral surface. Intraoperative fluoroscopy was used throughout surgery in all cases. Postoperative alignment in the frontal and sagittal planes was compared to the contralateral limbs. Time to clinical union, clinical outcome, and complications were recorded., Results: Three dogs were included. Body weight ranged from 5.9 to 40 kg. Incomplete ossification of the humeral condyle was identified as the primary pathology leading to the fracture in 2 cases. All cases experienced uncomplicated healing with good to excellent functional recovery., Conclusion: The reported technique was associated with good outcomes without complications in 3 cases., Clinical Significance: This study provides evidence that minimally invasive plate osteosynthesis represents an alternative to open reduction and internal fixation in the treatment of comminuted humeral T-Y fractures., (© 2019 The American College of Veterinary Surgeons.)

Objective:  The aim of this study was to evaluate epoxy-pin external skeletal fixation technique for the treatment of open fractures in calves and foals., Study Design:  Twenty-eight calves and four foals (weighing 45-105 kg) with fractures distal to the stifle or elbow made the subject for the retrospective study. The pins (2.0-3.0-mm Kirschner wires, crossed at 60-90°) were fixed at least at two locations in both proximal and distal bone fragments as per the case situation. The pins in the same plane were bent (∼2 cm from the skin) towards the fracture site or joint and were joined using an adhesive tape (additional pins used when required) to make a temporary scaffold of connecting bars or rings. Thoroughly mixed epoxy putty was applied along the pin scaffold (the epoxy columns were 20-25 mm diameter) and allowed to set for 45 to 60 minutes. All animals were evaluated based on various clinical and radiographic observations made at regular intervals., Results:  The epoxy-pin fixation was easy to apply and provided stable fixation of bone as indicated by early weight bearing, and fracture healing within 45 to 60 days (17/32 cases). The functional recovery was good to very good in 14 animals and satisfactory in nine cases by 12 months after removal of the fixator., Conclusions:  The multiplanar epoxy-pin external skeletal fixation provides stable fixation of unstable open fractures distal to the stifle or elbow joint; hence, it can be used to treat a variety of fractures in calves and foals weighing up to approximately 100 kg, especially open infected fractures of lower limb, which are difficult to treat by conventional techniques., Competing Interests: Dr. Aithal has a patent null pending., (Georg Thieme Verlag KG Stuttgart · New York.)

CASE DESCRIPTION A 2-year-old male bearded dragon (Pogona vitticeps) was evaluated because of a traumatic mandibular fracture. CLINICAL FINDINGS An open comminuted fracture of the rostral aspect of the right mandible was evident, with a fragment of bone exposed and dorsally displaced. Whole-body radiography revealed no evidence of additional injury. Other findings were unremarkable, except for moderate anemia (PCV, 19%). TREATMENT AND OUTCOME The fracture fragments were stabilized with 2 crossed 36-gauge interfragmentary wire loops. An external fixator device was fashioned from four 25-gauge needles inserted at alternating angles through the fracture fragments; plastic IV fluid line tubing filled with dental acrylic was used as a connecting bar. One day after surgery, the lizard had regained its typical activity level and appetite. Body weight was measured and the external fixator was inspected 1 week after surgery and monthly thereafter. Three months after initial injury, the fracture was stable, radiography revealed bony callus formation at the fracture site, and the external fixator was removed. Recheck radiography performed 5.5 months after initial injury revealed complete osseous union of the fracture fragments, and the interfragmentary wires were removed. CLINICAL RELEVANCE Surgical management of the traumatic comminuted mandibular fracture in this bearded dragon by means of a combination of internal and external fixation resulted in complete healing of the mandible and restoration of function. Management of this complicated fracture was achieved with the aid of readily available and inexpensive supplies in a clinical setting, which may be useful to other clinicians in the management of similar cases.

Objectives:  This article aimed to describe olecranon fracture in dogs and cats and their stabilization with tension band wiring or plate osteosynthesis, and to evaluate complications associated with each technique., Methods:  Medical records of cats and dogs that had been surgically treated for olecranon fractures with either tension band wiring or plate osteosynthesis were retrospectively reviewed. The surgical technique, complications and long-term outcomes were assessed., Results:  Forty-one olecranon fractures were included. Fractures were articular, comminuted and open in 90, 31 and 27% of cases, respectively. Tension band wiring and plate osteosynthesis were performed in 22 and 19 fractures, respectively. Complications occurred more commonly after tension band wiring (74%) compared with plate osteosynthesis (27%) ( p  = 0.002) and these were probably related to it being used in comminuted fractures ( p  = 0.01) or to errors in technique. Minor complications included Kirschner wires migration ( n  = 5), pain ( n  = 3), osteomyelitis ( n  = 3), skin breakdown ( n  = 3) and seroma ( n  = 1). Implant failure requiring further fixation ( n  = 4) was observed only in the tension band wiring group. Other major complications included skin wound debridement and closure ( n  = 1) and chronic lameness requiring implant removal ( n  = 7). Long-term functional outcomes were excellent regardless of the technique used., Clinical Significance:  Plate osteosynthesis should be performed for olecranon fracture repair if technically feasible., Competing Interests: Conflict of Interest: The authors have no conflict of interests with regard to this manuscript., (Schattauer GmbH Stuttgart.)

A 1-yr-old female Congo African grey parrot ( Psittacus erithacus erithacus) was admitted with a lameness of the right pelvic limb. On the radiographs a closed, caudolaterally displaced, comminuted, diaphyseal fracture of the femur was diagnosed. Surgery under general anesthesia was performed in order to repair the fracture with a paracortical-clamp-cerclage technique. This straightforward and effective technique has been developed as a low-cost treatment for simple and comminuted diaphyseal fractures in dogs and cats. Fixation is obtained with clamps, shaped during surgery, and attached to the bone shaft with cerclage wire. This technique led to immediate weight-bearing, appropriate bone healing, and permanent fixation of the implants in the patient. To the best of the authors' knowledge, this case represents the first report of a surgical repair of a femoral fracture with a paracortical-clamp-cerclage technique in a bird.

Background: The physis is the weakest component of immature long bones, and physeal fractures constitute about 30% of fractures in growing dogs. Fractures of the proximal humeral physis typically have a Salter Harris type I or II configuration. These fractures require accurate reduction and adequate stabilization to allow for any potential continued longitudinal bone growth, in conjunction with physeal fracture healing. Conventional internal fixation of these fractures involves insertion of two parallel Kirschner wires, although other methods described include tension band wiring, Rush pinning, and lag screws. However these recommendations are based on anecdotal evidence, and information about the biomechanical stability of physeal fracture repair is sparse. The unique anatomical structure of the epiphyseal-metaphyseal complex makes the gripping of the epiphysis for ex vivo biomechanical testing of physeal fracture repair very challenging. The objective of our study was to biomechanically assess the optimal number (three, two or one) of implanted Kirschner wires in a porcine Salter Harris I proximal humeral physeal fracture model, using motion analysis tracking of peri-fragmental retro-reflective markers while constructs were subjected to a constant axial compression and a sinusoidal torque of +/- 2 Nm at 0.5 Hz for 250 cycles., Results: There were significant differences between the three constructs (three, two or one Kirschner wire repair) for gross angular displacement (p < 0.001). The difference between three pins and two pins on toggle was not significant (p = 0.053), but both three-pin and two-pin fixation significantly reduced rotational toggle compared to one-pin fixation. Construct stiffness was not significantly different between any of the pin groups (p > 0.33)., Conclusions: Motion analysis tracking using peri-fragmental markers in this porcine model of physeal fracture repair found that the stability at the fracture site of one-pin fixation was significantly less than two-pin and three-pin fixation. Whether there was increased stabilization of these fractures with three-pin fixation compared to two-pin fixation was not conclusive in this porcine model.

Objective: To compare the biomechanical properties of using an interfragmentary 1.6 mm Kirschner wire or a 2.7 mm reconstruction plate as adjunctive epicondylar stabilization in simulated comminuted lateral unicondylar humeral fractures stabilized with a transcondylar 4.5 mm cortical screw., Study Design: Cadaveric biomechanical assessment., Sample Population: Paired humeri harvested from 9 young, skeletally mature dogs., Methods: Simulated comminuted lateral unicondylar humeral fractures were stabilized with a transcondylar 4.5 mm cortical screw placed in lag fashion. Adjunct fixations consisting of a 1.6 mm Kirschner wire on one side, and a 2.7 mm reconstruction plate on the contralateral side, were tested within paired humeri. Repaired humeri were axially loaded to failure and construct stiffness, yield load, and load to failure were obtained from the load-deformation curves., Results: Stiffness (mean ± SD: 577 ± 245 vs 310 ± 71 N/mm; P = .01), yield load (mean ± SD: 2389 ± 572 vs 1017 N ± 292; P = .0002), and load at failure (mean ± SD: 3351 ± 358 vs 1693 ± 363 N; P = .009) were greater in constructs incorporating a reconstruction plate rather than a Kirschner wire., Conclusion: Our results support the recommendation for adjunct fixation of comminuted lateral unicondylar humeral fractures with an epicondylar plate., (© 2017 The American College of Veterinary Surgeons.)

Angular limb deformities are common in foals; however, the importance of the deformity and if treatment is required depend on the degree of deformity relative to normal conformation for stage of growth, the breed and discipline expectations, age, and response to conservative therapies. This article addresses the importance of the foal conformation examination to determine which foals need surgical intervention to correct an angular deformity and when. Techniques for surgical growth retardation include the transphyseal staple, screw and wire transphyseal bridge, and transphyseal screw. Appropriate timing for intervention for each location and complications associated with each procedure are discussed., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objectives The objective was to describe the complications and long-term outcome associated with Kirschner (K)-wire fixation of combined distal radial and ulnar physeal fractures in six cats. Methods Medical records (2002-2014) of six referral institutions were searched for cats with combined distal radial and ulnar physeal fractures. Cases with complete clinical files, radiographs and surgical records were retrospectively reviewed. Long-term outcome was assessed via telephone interviews using an owner questionnaire. Results Complete files were available for 6/9 identified cases (cases 1-6). All fractures were classified as Salter-Harris type I or II. Five cases underwent open reduction and internal fixation via cross-pinning of the distal radius and intramedullary pinning of the ulna (cases 1-3); fixation of the distal radial and ulnar physes with one K-wire each (case 4); and K-wire fixation of the radial physis in combination with two transulnoradial K-wires (case 5). One case underwent closed reduction and percutaneous cross-pinning of the distal radius under fluoroscopic guidance (case 6). The complications encountered were: reduced radiocarpal range of motion (ROM) (cases 1, 3, 4, 5); implant loosening/migration (cases 1, 2, 5); and radioulnar synostosis (case 4). None of the cats developed angular limb deformity. Long-term outcome (12 months to 7 years after surgery) was graded as 'excellent' by the owners in all cases. Conclusions and relevance Prognosis is favourable for feline combined distal radial and ulnar physeal fractures following K-wire fixation in cats over 7 months of age. Implant removal after bony union is recommended to minimise reduction in ROM and to prevent implant loosening/migration.

Longitudinal patellar fractures in cats are extremely rare with only 1 other report of a comminuted longitudinal fracture for which pins and wires were placed in the patella for stabilization. This report describes the surgery and outcome of a strictly longitudinal patellar fracture in a cat.

Objective: To investigate four techniques for stabilization of feline patellar fracture., Methods: Feline cadaveric stifles with simulated patellar fracture were stabilized with one of four techniques: Group A - circumferential wire, group B - figure-of-eight wire, group C - combined figure-of-eight and circumferential wire, group D - pin and tension band wire. All repairs were subjected to a period of cyclic loading prior to load to failure testing. Experiments were recorded by video capture to determine load at failure and failure mode. Failure was defined as an opening of the fracture gap of 3 mm., Results: Mean fracture gap opening (±SD) during peak loading after 1000 cycles was: group A with 1.66 mm (± 0.69), group B with 1.01 mm (± 0.45), group C with 0.81 mm (± 0.58), and group D with 0.65 mm (± 0.54). Groups C and D had significantly lower mean fracture gap opening after 1000 cycles when compared to group A (p <0.05). Mean loads (± SD) at failure were: group A with 171.4 N (± 62.2), group B with 208.7 N (± 20.7), group C with 288.2 N (± 62.5), and group D with 219.5 N (± 48.0). Group C had significantly higher mean load to failure than all other groups (p <0.05). There was no difference between other groups. In groups A, B and C the principle mode of failure was wire elongation and tearing of sutures through the retinaculae and periarticular soft tissues. In group D, the principle mode of failure was the pin pulling through the bone of the distal fragment., Conclusions: Combined figure-of-eight and circumferential wires may be useful for treatment of transverse feline patellar fracture.

Objectives: To evaluate the use of Kirschner wires for treatment of fractures of the lateral aspect of the humeral condyle in growing dogs., Methods: Retrospective analysis of 35 elbow fractures (33 dogs) of the lateral aspect of the humeral condyle treated by insertion of multiple transcondylar and one anti-rotational Kirschner wires. Radiographic and clinical re-evaluations were carried out immediately after surgery, at four weeks and, when required, at eight weeks postoperatively. Long-term follow-up was planned after a minimum of six months. The relationship between different implant configurations and clinical outcome was analysed statistically., Results: Complete functional recovery was seen in 31 elbows (30 dogs), three elbows (2 dogs) had reduction in the range of motion, and one elbow (1 dog) had persistent grade 1 lameness two months postoperatively. Major complications occurred in eight elbows (8 dogs) and all were resolved by implant removal. Implant configuration did not affect outcome. Long-term evaluation in 12 cases with a mean follow-up of four years showed absence of lameness, normal function and no or mild radiographic evidence of osteoarthritis in 11 cases., Clinical Significance: Fracture of the lateral aspect of the humeral condyle in growing dogs can be successfully treated by multiple transcondylar convergent or parallel Kirschner wires, resulting in adequate fracture healing.

Periprosthetic femoral fractures are a common complication associated with cementless press-fit total hip arthroplasty. The use of prophylactic cerclage wire fixation has been advocated to reduce this complication. The objective of this study was to evaluate whether a double loop cerclage wire, used as adjunctive fixation, increased the peak torsional load to failure in femora implanted with press-fit cementless stems. Peak torsional load to failure was compared between femora without adjunctive fixation and femora receiving a 1 mm double loop cerclage wire placed proximally to the lesser trochanter. Femora treated with adjunctive cerclage wire fixation failed at 20% greater peak torque (P = 0.0001). In conclusion, a double loop cerclage wire may aid in the prevention of periprosthetic fractures associated with press-fit cementless femoral stems., (Copyright © 2016. Published by Elsevier Ltd.)

Objective: Evaluate the effects of supplemental fixation elements on the mechanical properties of a single ring circular fixator construct., Study Design: In vitro mechanical testing., Sample Population: Five construct configurations (six replicates of each configuration) were used to stabilize a 1.6 cm diameter Delrin rod bone model., Methods: Constructs were assembled using 66 mm complete rings, 1.6 mm olive wires, and 3.2 mm diameter half-pins. Construct configurations tested were a base single ring construct, constructs with 1 supplemental drop wire or constructs with 1, 2, or 3 supplemental half-pins. Constructs were loaded in axial compression, caudocranial and mediolateral bending, and torsion. Strain was measured in individual fixation elements during axial loading., Results: A supplemental drop wire or half-pin significantly increased bending and torsional stiffness. The supplemental half-pin increased caudocranial stiffness significantly more than placing a drop wire. Placing a 2nd or 3rd pin afforded significantly greater increases in construct stiffness in all modes of loading, with 3 half-pin constructs having significantly greater axial and caudocranial stiffness than 2 half-pin constructs. Placing a single supplemental pin induced cantilever bending resulting in angular displacement of the Delrin rod during axial loading and high strain in both the fixation wire secured distal to the ring and the pin. Supplemental half-pins incrementally reduced strain in all fixation elements and resulted in linear displacement of the Delrin rod during axial loading., Conclusion: If using supplemental half-pins as fixation elements, insertion of 2 or 3 pins is preferred over a single pin., (© Copyright 2016 by The American College of Veterinary Surgeons.)

Cerclage wire is widely used in the treatment of fracture internal fixation and is shown effective in clinic. But a report by S.L. has pointed that the wire loop delayed the growth of bone. We have established a radius fracture model to study the possible detrimental effects of cerclage wire on fracture healing and the potential mechanism. By high-resolution CT analysis cerclage wire is found to delay fracture healing, by histological assessment cerclage wire is found to extended the time of hematoma and the marrow cavity appearing, by confocal microscopy cerclage wire decreased the content of calcium and the expression of alkaline phosphatase (ALP), and by RT-PCR analysis cerclage wire decreased the mRNA levels of bone sialoprotein and ALP. These results suggest that the cerclage wire near the elbow delayed the fracture healing in radius fracture models., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Fracture of the central tarsal bone is an uncommon injury in dogs and occurs predominantly in racing Greyhounds. To the authors' knowledge, this type of fracture has not been described previously in cats. This case report describes a five-year-old Domestic Shorthair cat referred to the Centro Veterinario Luni Mare because of lameness, swelling and signs of pain in the right hindlimb caused by trauma. Clinical examination and diagnostic imaging revealed a right central tarsal bone fracture. Open reduction and internal fixation with a 2.0 mm position screw and two 0.8 mm Kirschner wires were carried out. The last follow-up examination three years postoperatively found the cat in good health with normal range of motion and function, and no signs of lameness in the right hindlimb.

Objective: To compare a locking plate (LP) with pin and tension-band wire (pin/TBW) for fixation of mid-patellar transverse fractures., Materials and Methods: Cadaveric canine stifle joints from 10 adult mixed breed dogs (23-36 kg) were used. Mid-patellar transverse osteotomies were randomly stabilized (in pairs) with either pin/TBW or a prototype LP. Cyclic loads (1 Hz, 500 cycles) at 100% body weight (90°-135° stifle joint extension), were applied. Survival or failure of constructs was defined as <2 mm fracture gap distraction at 500 cycles, or ≥2 mm fracture gap distraction at the number of cycles sustained, respectively. Number of cycles at failure and distraction gap were compared with a paired Student's t-test, and a survival analysis performed with a Mantel-Cox test. All constructs that survived cyclic testing were tested in single cycle load to failure (1.0 mm/sec; 110° stifle joint extension); yield strength was compared with a Wilcoxon rank sum test. Significance was set at p <0.05., Results: All 10/10 LP and three out of 10 pin/TBW fixations survived cyclic testing. Survival analysis, number of cycles at failure, and distraction gap all were significantly different between the two groups (p = 0.0011, p = 0.0013, and p <0.0001, respectively). Construct yield strength was not significantly different (p = 0.1273)., Conclusions: The failure mode with pin/TBW was consistently similar to failures observed clinically. The LP demonstrated consistent, reliable and stable fixation.

Objectives: To compare the mechanical properties of monofilament nylon leader and orthopaedic wire for median sternotomy closure in the dog., Materials and Methods: Median sternotomy was performed in 14 canine cadaver sternums with the manubrium intact. The sternotomy was closed with either 80 lb monofilament nylon leader or 20G orthopaedic stainless steel wire in a peristernal figure of 8 pattern. Constructs were loaded in a servohydraulic material testing machine. Load at yield, maximum load, stiffness, displacement and mode of failure were compared between constructs subjected to a single cycle load to failure., Results: No significant differences were found in load at yield, maximum load, stiffness or displacement between the monofilament nylon leader and the stainless steel wire constructs. No implant failure was evident in the stainless steel wire constructs. Four of the monofilament nylon leader constructs failed by pulling of the nylon through the crimp., Clinical Significance: Monofilament nylon leader is mechanically comparable to stainless steel wire and potentially a suitable alternative for closure of median sternotomy in the dog., (© 2015 British Small Animal Veterinary Association.)

Drilling trials were performed using drilling boards incorporating pairs of 22 mm polyethylene tubes mounted horizontally. The tubes were premarked with 20, 0.5 mm deep notches along the centre of their upper surface representing the starting point for each drilling trial. Volunteers were instructed to drill 20 straight holes across the tube until they penetrated both walls. Kirschner wires were inserted through each of the drill holes until they made indentations into the base board. Deviation of each mark from mid-line was measured using digital callipers. The measured values were used to calculate deviation angles to the left (negative values) or right (positive values). Trials were performed with the drill and guide held in the surgeon's line-of-sight (LOS) and with 300 mm offset (OFF). A systematic error (aiming bias) was identified in all individuals. Overall, left-hander's drilling action was skewed to the left and right-hander's drilling action was skewed to the right. Using LOS technique, mean overall bias was 2.3° (range 0°-7.7°) to the left for left-handers and 1.5(o) (range 0.3°-3.1°) to the right for right-handers. Surprisingly, aiming bias was greater for LOS than for OFF, although the difference for this comparison was not statistically significant., (British Veterinary Association.)

Objectives: To assess the impact of stabilization method on the complication rate after lateral humeral condylar fracture (LHCF) repair., Study Design: Retrospective multicenter clinical cohort study., Animals: Dogs (n = 151) with LHCF., Methods: Medical records (2004-2012) were reviewed for dogs that had surgical repair of LHCF. Data retrieved included signalment, cause of fracture, evidence of incomplete ossification of the humeral condyle, occurrence of postoperative complications, presence of supracondylar comminution preoperatively, and persistence of an intracondylar fissure postoperatively. Outcome was assessed based on the most recent data available and graded as excellent, good, fair, or poor., Results: LHCF (n = 135) were evaluated in 132 dogs; 61 fractures were stabilized using a transcondylar screw and supracondylar K-wire, 13 using a transcondylar screw and supracondylar screw, and 61 using a transcondylar screw and lateral epicondylar plate. Major complications were significantly (P = .01) more common after stabilization using a transcondylar screw and supracondylar K-wire (28%) than in dogs where a supracondylar screw or lateral epicondylar plate were used (11%). Cases that had postoperative complications were significantly (P = .02) more likely to have a poor outcome., Conclusions: LHCF stabilized using a transcondylar screw and supracondylar K-wire are more likely to have major complications resulting in a poorer outcome than cases stabilized using a supracondylar screw or lateral epicondylar plate., (© Copyright 2014 by The American College of Veterinary Surgeons.)

Three silver arowana (Osteoglossum bicirrhosum) were presented with unstable fractures of the mandibular symphyses. Surgical repair was performed to reduce and stabilize the fractures using interfragmentary wire. The fish returned to light feeding at 2 days and normal feeding at 5 days postsurgery. The wires were removed at 6 wk postsurgery with good alignment of the mandibular symphyses and stable fracture sites. There had been no further complications at the time of writing 18 wk postsurgery.

Objective: To compare the in vitro biomechanical effects of single loop cerclage wires, an intramedullary pin and the combination thereof as applied to an oblique mid-diaphyseal osteotomy of canine tibiae., Methods: Three groups of nine bones with long oblique osteotomies were repaired with the following methods: 1) Three single loop cerclage wires and a transcortical skewer pin, 2) intramedullary pinning with a smooth Steinmann pin, and 3) a combination of both methods. The repaired constructs were tested in a single cycle four-point-bending test to failure. Load displacement curves were drawn and the following parameters were calculated or extrapolated: Stiffness, load at yield, and force resisted at 2 mm actuator displacement. The latter was determined to demonstrate the difference in the amount of energy absorbed between the different groups., Results: The stiffness and force resisted at 2 mm displacement of the groups with cerclage wires were significantly higher than the group with an intramedullary pin alone (p ≤0.05). The differences in stiffness (p = 0.15) and force required at 2 mm displacement (p = 0.56) between cerclage wires and the combination of cerclage wires and intramedullary pins were not significant., Clinical Relevance: Cerclage wire repair results in higher stiffness than repair with an intramedullary pin. When cerclage wires are combined with an intramedullary pin, the intramedullary pin does not provide protection to the cerclage wire repair and the wires or the bone under the wires has to fail before the pin resists significant load.

Objectives: To compare radiography and computed tomography (CT) for the evaluation of medullary cavity diameters of metacarpal and metatarsal bones in cats and to analyse their correlation with intramedullary pin size., Methods: Radiography and CT were performed in cadavers (n = 12). The mid-diaphysis was determined and the medullary cavity diameter was measured by two observers. Each bone was osteotomized at the mid-diaphysis, Kirschner wires were inserted, and pin size was documented. Intra- and interobserver variability was evaluated (hierarchical analysis of variance). Radiography and CT were compared (correlation analysis, a t-test for dependent samples, a Bland-Altman analysis) and pin size, radiography and CT were compared (regression and correlation analysis)., Results: Intra-observer variability was low for radiographs and CT, with an estimated median variation of 0.10 mm for radiographs and 0.12 mm for CT. Inter-observer variability was low, with a median variation of 0.03 mm for radiographs and 0.21 mm for CT. There was a high correlation between radiography and CT for the assessment of the medullary cavity diameter. A high correlation was found between pin size and measurement on radiographs, and between pin size and measurements on CT. In two cats, pin insertion was difficult or impossible., Clinical Significance: Mid-diaphyseal measurements are applicable methods for the assessment of the medullary cavity diameter in feline metacarpal and metatarsal bones regarding intramedullary pins. In some cats the medullary cavity diameter may be too small for intramedullary pinning techniques, which can be identified preoperatively on radiographs.

An 11-year old, female, Mix Breed dog was presented after being hit by a car with a rupture of the left patellar ligament. Due to a suspected wound infection close to the stifle joint, surgical repair was delayed for 10 days. The ruptured ligament was sutured and augmented with fascia lata. Additionally, two ComPact UniLock 2.4/3.0 mm plates connected with 1.0 mm orthopaedic wire were used to protect the primary repair. No immobilization of the stifle joint was needed. The implants were removed after 7 weeks, because of suspected infection and loosening. The successful utilization of an alternative surgical technique for the repair of the patellar ligament rupture in the dog has also been documented by pre- and post-operative temporal-spatial gait analysis (GaitFour®).

Objective: Evaluate effect of adding drop wires to single-ring constructs., Study Design: Biomechanical study, Sample Population: Single ring circular external skeletal fixator constructs stabilizing a Delrin segment bone model., Methods: Eight replicates of 5 constructs made with 66 mm complete rings, 1.6 mm olive wires, and a 15.9-mm diameter Delrin rod were loaded in axial compression, craniocaudal and mediolateral bending, and torsion. Constructs tested were: (1) base single-ring construct; (2) single-ring construct with a drop wire mounted on fixation bolts; (3) single-ring construct with a drop wire mounted on 1-hole posts; (4) single-ring construct with a drop wire mounted on 2-hole posts; and (5) 2-ring construct. Construct stiffness for each mode of loading was compared using repeated measures ANOVAs (P ≤ .05)., Results: Axial compression and torsion: the 2-ring construct was stiffer than all others. Drop wire constructs were stiffer than the single-ring construct, but not significantly different from each other. Craniocaudal bending: the 2-ring construct was stiffest with the 2-hole post construct being stiffer than all except the 2-ring construct. Mediolateral bending: the 2-hole post construct was stiffer than the 2-ring construct, which was stiffer than the 1-hole post construct, which was stiffer than the fixation-bolt construct, which was stiffer than the single-ring construct., Conclusions: Drop wires improved stiffness of single-ring constructs in all loading modalities. Positioning the drop wire farther from the ring surface significantly improved craniocaudal and mediolateral bending stiffness, but did not affect axial compression and torsional stiffness., (© Copyright 2013 by The American College of Veterinary Surgeons.)

Objective: To compare complication rates and the outcomes of these complications after lateral plate fixation with figure-of-eight tension-band-wire and pin or lag screw fixation for arthrodesis of the calcaneoquartal joint, following non-traumatic disruption of the plantar tarsal ligament in dogs., Methods: Data were collected retrospectively from five UK referral centres. Diplomate specialists and their residents performed all procedures. Referring veterinarians were contacted for long-term follow-up., Results: Seventy-four procedures were undertaken in 61 dogs. There were 58 arthrodeses in the lateral plate group (Plate), nine in the pin and tension-band-wire group (Pin), and seven in the lag screw and tension-band wire-group (Screw). Compared to Plate (17%), further surgical intervention was required more frequently following Pin (56%, OR = 3.2) or Screw (43%, OR = 2.5) fixation. Clinical failure of arthrodesis occurred less frequently with Plate (5%) compared with Screw (43%, OR = 8.6) and Pin fixation (22%, OR = 4.4). Cases managed with external coaptation postoperatively were more likely to suffer from postoperative complications (OR = 2.2)., Clinical Significance: Lateral plating was associated with fewer postoperative complications than pin and tension-band-wire fixation for arthrodesis of the calcaneoquartal joint in dogs with non-traumatic disruption of the plantar tarsal ligament.

Objective: To compare the axial stiffness, maximum axial displacement, and ring deformation during axial loading of single complete and incomplete circular (ring) external skeletal fixator constructs., Sample: 32 groups of single ring constructs (5 constructs/group)., Procedures: Single ring constructs assembled with 2 divergent 1.6-mm-diameter Kirschner wires were used to stabilize a 60-mm-long segment of 16-mm-diameter acetyl resin rod. Construct variables included ring type (complete or incomplete), ring diameter (50, 66, 84, or 118 mm), and fixation wire tension (0, 30, 60, or 90 kg). Axial loading was performed with a materials testing system. Construct secant stiffness and maximum displacement were calculated from the load-displacement curves generated for each construct. Ring deformation was calculated by comparing ring diameter during and after construct loading to ring diameter prior to testing., Results: Complete ring constructs had greater axial stiffness than did the 66-, 84-, and 118-mm-diameter incomplete ring constructs. As fixation wire tension increased, construct stiffness increased in the 66-, 84-, and 118-mm-diameter incomplete ring constructs. Maximum axial displacement decreased with increasing fixation wire tension, and complete ring constructs allowed less displacement than did incomplete ring constructs. Incomplete rings were deformed by wire tensioning and construct loading., Conclusions and Clinical Relevance: Mechanical performance of the 66-, 84-, and 118-mm-diameter incomplete ring constructs improved when wire tension was applied, but these constructs were not as stiff as and allowed greater displacement than did complete ring constructs of comparable diameter. For clinical practice, tensioning the wires placed on 84- and 118-mm-diameter incomplete rings to 60 kg is recommended.

Objective: To determine mechanical properties of various prosthetic materials secured to cadaveric canine femurs via various methods and to compare results with those for isolated loops of prosthetic material., Sample: 80 femurs obtained from cadavers of skeletally mature large-breed dogs., Procedures: 10 femoral constructs in each of 8 groups (single circumfabellar loop of polyethylene cord, double loop of polyethylene tape secured via a bone anchor [BAPT], single or double circumfabellar loops of nylon leader material [CNL] or polyethylene tape [CPT], or single or double loops of polyethylene tape secured via a toggle placed through a bone tunnel [BTPT]) and 10 isolated loops of prosthetic material in each corresponding configuration were tested. Stress relaxation, creep, elongation, load at 3 mm of displacement, stiffness, and peak load at failure were determined., Results: 5 single CNL constructs failed before completion of testing. Double CNL and single circumfabellar polyethylene cord constructs had the lowest loads at 3 mm of displacement. Single and double CPT constructs had the highest stiffness. Double BTPT and CPT constructs had the highest peak loads at failure. Double BTPT, double CPT, and BAPT constructs were mechanically superior on the basis of lower creep and stress relaxation and higher stiffness and load at 3 mm of displacement versus other constructs. Stiffness of femoral constructs was 28% to 69% that of corresponding isolated prosthetic loops., Conclusions and Clinical Relevance: Double BTPT, double CPT, and BAPT constructs were mechanically superior to other constucts. Mechanical properties and methods of anchorage and securing of free ends of prostheses contributed to mechanical properties of constructs.