Retrospective Comparison of Minimally Invasive Plate Osteosynthesis and Open Reduction and Internal Fixation of Radius-Ulna Fractures in Dogs

Efficacy of virtual surgical planning and a three-dimensional-printed, patient-specific reduction system to facilitate alignment of diaphyseal tibial fractures stabilized by minimally invasive plate osteosynthesis in dogs: A prospective clinical study

OBJECTIVE

To evaluate the efficacy of a three-dimensional (3D)-printed, patient-specific reduction system for aligning diaphyseal tibial fractures stabilized using minimally invasive plate osteosynthesis (MIPO).

STUDY DESIGN

Prospective clinical trial.

SAMPLE POPULATION

Fifteen client owned dogs.

METHODS

Virtual 3D models of both pelvic limbs were created. Pin guides were designed to conform to the proximal and distal tibia. A reduction bridge was designed to align the pin guides based on the guides' spatial location. Guides were 3D printed, sterilized, and applied, in conjunction with transient application of a circular fixator, to facilitate indirect fracture realignment before plate application. Alignment of the stabilized tibiae was assessed using postoperative computed tomography scans.

RESULTS

Mean duration required for virtual planning was 2.5 h and a mean of 50.7 h elapsed between presentation and surgery. Guide placement was accurate with minor median discrepancies in translation and frontal, sagittal, and axial plane positioning of 2.9 mm, 3.6°, 2.7°, and 6.8°, respectively. Application of the reduction system restored mean tibial length and frontal, sagittal, and axial alignment within 1.7 mm, 1.9°, 1.7°, and 4.5°, respectively, of the contralateral tibia.

CONCLUSION

Design and fabrication of a 3D-printed, patient-specific fracture reduction system is feasible in a relevant clinical timeline. Intraoperative pin-guide placement was reasonably accurate with minor discrepancies compared to the virtual plan. Custom 3D-printed reduction system application facilitated near-anatomic or acceptable fracture reduction in all dogs.

CLINICAL SIGNIFICANCE

Virtual planning and fabrication of a 3D-printing patient-specific fracture reduction system is practical and facilitated acceptable, if not near-anatomic, fracture alignment during MIPO.

Evaluation of a 3D-Printed Reduction Guide for Minimally Invasive Plate Osteosynthesis of Short Oblique Radial Diaphyseal Fracture in Dogs: A Cadaveric Study

This study aims to evaluate the clinical application of three-dimensional (3D)-printed custom reduction guides (3DRG) for minimally invasive plate osteosynthesis (MIPO) of short oblique radial diaphyseal fractures. Canine forelimb specimens (n = 24) were prepared and a diaphyseal short oblique fracture was simulated in the distal radius and ulna. Bone fragments were stabilized with the MIPO technique using a 3DRG (Group A), open reduction (Group B), or closed reduction with circular external skeletal fixation (ESF) (Group C). The diaphyseal short oblique fractures were created in each radius at one-third of the radial length from the distal radial articular surface. Surgical stabilization of the fractures was performed in each group. Pre and postoperative radiographic images were obtained to measure frontal angulation (FA), sagittal angulation (SA), frontal joint reference line angulation (fJRLA), sagittal joint reference line angulation (sJRLA), translational malalignment and fracture gap width. Surgical time was also measured. In the homogeneity test, differences in SA, sJRLA, craniocaudal translation and fracture gap before and after surgery had no significant difference among the three groups. On the other hand, differences in FA, fJRLA, mediolateral translation and surgical time before and after surgery had significant differences among the three groups. In the post hoc test, only surgical time showed a significant difference between the three groups, and group A showed the shortest surgical time. The use of 3DRG for MIPO of short oblique radial diaphyseal fractures in dogs is reliable for the alignment and apposition of fractures and reduces surgical time.

Feline radial and ulnar diaphyseal fractures: a retrospective study of 49 cases comparing single bone fixation and dual bone fixation

OBJECTIVES

The objectives of this study were to report the complications in radial and ulnar diaphyseal fractures in cats and to compare the differences in outcome between single and dual bone internal fixation.

METHODS

Medical records between 2004 and 2022 were searched retrospectively for cats with antebrachial diaphyseal fractures treated with internal bone-plate fixation. In total, 49 cases were included from six referral hospitals, including one teaching hospital. Patient information was collated, including fracture configuration, location, repair method and clinical outcome as assessed by veterinary physical examination, radiography and owner questionnaire.

RESULTS

A total of 47 cats (mean age 4.2 years) were included. Fractures were located distally (24/49, 49%), proximally (13/49, 26.5%) and mid-diaphyseally (12/49, 24.5%). Dual bone fixation was used in 13/49 (26.5%) cases, with only 1/13 (7.7%) having major complications. By comparison, 4/36 (11.1%) of single plated fractures had major complications. Single bone fixation was 14.25 times more likely (95% confidence interval [CI] 2.07-97.99) to have a successful outcome (veterinarian-assigned score of 0) compared with dual bone fixation (P = 0.007). When evaluating owner-assessed outcomes, single bone fixation was 9.4 times more likely (95% CI 1.4-61.96) to have a successful outcome (owner score of 0) compared with dual bone fixation (P = 0.019).

CONCLUSIONS AND RELEVANCE

Fractures that were repaired with single bone fixation had a greater chance of a better outcome. Although the difference was not significant, there was a higher major complication rate and a lower minor complication rate for cases treated with single bone fixation compared with dual bone fixation. The majority of fractures were located in the distal diaphysis. Comminution of the fracture and concurrent orthopaedic issues did not significantly affect the outcome. Further prospective studies with standardised follow-up, radiographic assessment, surgeon and implants are required to truly assess the difference between dual and single bone fixation.

Fracture Healing in 37 Dogs and Cats with Implant Failure after Surgery (2013-2018)

Implant failure is common in small animal orthopedics, but risk factors are rarely reported. Our objective was to determine whether abnormal fracture healing was associated with implant failure after fracture fixation in dogs and cats in a consecutive series of cases. Thirty-seven client-owned animals (thirty-two dogs, five cats) diagnosed with implant failure after fracture treatment from January 2013-September 2018 were studied. Medical and radiographic records were retrospectively reviewed to identify patients that underwent fracture fixation using open reduction and internal fixation with subsequent radiographic evidence of implant failure. Area moment of inertia (AMI), plate working length, and bone screw density were determined. Implant failure was found in 39 fractures in 37 animals, representing 23% of fracture cases during the study period. Cases of implant failure were at increased risk of delayed union, malunion, or non-union (p < 0.0001). The most common cause of implant failure was loosening (54%); the second most common was plate failure that included low AMI locking plates (28%). Major complications found in 22/39 fractures (56%) were associated with delayed union (p < 0.01). Surgical revision was performed in 49% of implant failure cases. Complications were most frequently identified after treatment of humeral fractures (26%). We conclude mechanical failure of implants increases the risk for delayed or abnormal fracture healing and often requires revision surgery. Implant AMI should be considered during preoperative planning. Locking plates are associated with implant failure if plate bending stiffness is not sufficient, based on findings from this case series.

A review of minimally invasive fracture stabilization in dogs and cats

OBJECTIVE

To summarize and discuss peer-reviewed studies on minimally invasive osteosynthesis (MIO) of long bone, physeal, and articular fractures in dogs and cats.

STUDY DESIGN

Invited review.

METHODS

A critique of literature was performed to assess MIO feasibility, outcomes, and complications through PubMed, Scopus, and CAB abstracts research databases (2000-2020).

RESULTS

More than 40 MIO articles have been published in the last 15 years, but most studies had small numbers, lacked control groups, and used limited outcome measures. Studies generally showed that MIO was feasible in dogs and cats with low complication rates. The current evidence does not demonstrate superior bone healing or functional outcomes with MIO when compared to standard methods. Although treatment principles, case selection, and techniques varied depending on the anatomical location, there were no salient differences in complication rates among long bones, physeal, and articular fractures treated by MIO.

CONCLUSION

The current available evidence and the personal experience of the authors support MIO as a promising fracture management modality. MIO can yield excellent outcomes when applied in carefully selected cases, performed by surgeons experienced in the technique. We cannot, however, conclude that MIO is superior to open fracture stabilization based on the available evidence in veterinary literature. Randomized controlled studies are warranted to prospectively compare MIO with other osteosynthesis techniques and thereby validate its role in fracture management for dogs and cats.

Use of a circular fixator construct to facilitate closed reduction and percutaneous stabilization of a distal femoral physeal fracture in a dog

Background:

Fractures of the distal femoral physis are the most common physeal fracture sustained by skeletally immature dogs. Reduction and stabilization of these fractures can sometimes be achieved through closed reduction, primarily in fractures that are nominally displaced. Circular external fixator constructs have been used to assist in indirect, closed reduction of fractures at other anatomic locations in dogs and this report describes application of this method to reduce a displaced Salter-Harris type II fracture of the distal femur in a 1-year-old dog.

Case Description:

A 1-year-old female spayed Akita was referred for treatment of a Salter-Harris type II fracture of the right distal femur. The epiphyseal segment was laterally and slightly caudally displaced. Multiple attempts to manually reduce the fracture during surgery were unsuccessful, so a two-ring circular external fixator construct was applied to facilitate distraction and reduction. The construct was applied by placing a medial-to-lateral Kirschner wire in both the mid-femoral diaphysis and in the distal femoral epiphysis. Distraction of the construct provided sufficient separation of the fracture segments to facilitate near anatomic reduction. The fracture was stabilized with two percutaneously placed Steinmann pins placed in Rush fashion. Radiographic union was confirmed 5 weeks after surgery. The dog was not lame and was bearing more weight on the right pelvic limb, as assessed using force plate analysis, 9 months following surgery. Goniometric measurements of stifle range of motion and thigh muscle circumference were similar between the pelvic limbs.

Conclusion:

Application of a two-ring circular construct would appear to be useful to facilitate closed reduction and percutaneous stabilization of distal femoral physeal fractures.

Impaired bone quality characterized by apatite orientation under stress shielding following fixing of a fracture of the radius with a 3D printed Ti-6Al-4V custom-made bone plate in dogs

Custom-made implants have recently gained attention in veterinary medicine because of their ability to properly fit animal bones having a wide variety of shapes and sizes. The effect of custom-made implants on bone soundness and the regeneration process is not yet clear. We fabricated a 3D printed Ti-6Al-4V custom-made bone plate that fits the shape of the dog radius, and placed it into the radius where an osteotomy had been made. The preferential orientation of the apatite c-axis contributes to the mechanical integrity of the bone and is a reliable measure of bone quality. We determined this parameter as well as the bone shape and bone mineral density (BMD). The bone portion which lies parallel to the bone plate exhibited bone resorption, decreased BMD, and significant degradation of apatite orientation, relative to the portion outside the plate, at 7 months after the operation. This demonstrates the presence of stress shielding in which applied stress is not transmitted to bone due to the insertion of a stiff bone plate. This reduced stress condition clearly influences the bone regeneration process. The apatite orientation in the regenerated site remained different even after 7 months of regeneration, indicating insufficient mechanical function in the regenerated portion. This is the first study in which the apatite orientation and BMD of the radius were evaluated under conditions of stress shielding in dogs. Our results suggest that assessment of bone repair by radiography can indicate the degree of restoration of BMD, but not the apatite orientation.

Minimally Invasive Fracture Repair of the Tibia and Fibula

Fractures of the tibia and fibula are common in dogs and cats and occur most commonly as a result of substantial trauma. Tibial fractures are particularly amenable to treatment using minimally invasive fracture repair (MIFR) techniques that preserve blood supply to comminuted fracture fragments, accelerating bone callus production and speeding fracture healing. Treatment of tibial fractures using MIFR techniques has been found to reduce surgical time, reduce the time for fracture healing, and to decrease patient morbidity, while at the same time reducing complications compared with traditional open reduction and internal fixation.

Minimally Invasive Plate Osteosynthesis: Radius and Ulna

Minimally invasive plate osteosynthesis (MIPO) is a biologically friendly approach to fracture reduction and stabilization that is applicable to many radius and ulna fractures in small animals. An appropriate knowledge of the anatomy of the antebrachium and careful preoperative planning are essential. This article describes the MIPO technique, which entails stabilization of the fractured radius with a bone plate and screws that are applied without performing an extensive open surgical approach. This technique results in good outcomes, including a rapid time to union and return of function.

Minimally Invasive Plate Osteosynthesis Fracture Reduction Techniques in Small Animals

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

Perceptions of minimally invasive osteosynthesis: A 2018 survey of orthopedic surgeons

OBJECTIVE

To report perspectives of minimally invasive osteosynthesis (MIO) techniques in veterinary surgical practice in 2018.

STUDY DESIGN

Electronic questionnaires.

SAMPLE POPULATION

Diplomates and residents of the American College of Veterinary Surgery and European College of Veterinary Surgery and members of the Veterinary Orthopedic Society.

METHODS

Survey questions pertaining to MIO and minimally invasive plate osteosynthesis (MIPO) were sent electronically to the sample population. Questions assessed training, current caseload, benefits, and limitations of MIO and MIPO.

RESULTS

Two hundred fifty-six veterinary surgeons completed questions pertaining to MIO, and 238 veterinary surgeons completed questions pertaining to MIPO. With regard to MIO, only 16% of respondents reported that they performed MIO regularly or exclusively, and 62% wanted to perform more MIO than they were currently undertaking. Tibial fractures were most commonly selected for MIO/MIPO stabilization techniques in both cats and dogs. Challenges in achieving adequate fracture reduction were identified as the greatest limitations of MIO/MIPO techniques. Forty-three percent of respondents felt there were not enough MIPO training opportunities.

CONCLUSION

Currently, MIO/MIPO techniques are performed infrequently, with a large proportion of respondents revealing that they would like to perform more in the future. There is also evidence that additional training opportunities would be welcomed for MIPO.

CLINICAL SIGNIFICANCE

The results of our survey provide evidence that, despite the benefits of MIO and MIPO compared with more traditional fracture stabilization approaches, significant barriers must be overcome before the techniques are likely to be more widely adopted.

Bacterial osteomyelitis in veterinary orthopaedics: Pathophysiology, clinical presentation and advances in treatment across multiple species

Bacterial osteomyelitis in veterinary patients can be challenging to diagnose and treat, given limited therapeutic options and reported success rates. Osteomyelitis is frequently associated with surgical implant devices, including those required to optimise stability and healing of fractures. However, management of osteomyelitis sometimes necessitates the removal of these surgical implant devices in order to eradicate infection or limit implant-related osteolysis. The goal of this article is to provide a general and species-specific review of bacterial osteomyelitis in a selection of domestic veterinary species, including cats, dogs, horses, cattle and camelids, with a focus on classification, clinical presentation, aetiologic agents, and common therapeutic interventions reported in the literature. New treatment options emerging from research and human medicine will be also discussed, as they also apply to current or future care of veterinary patients with osteomyelitis.

Use of the Minimally Invasive Reduction Instrumentation System for Facilitating Alignment and Reduction When Performing Minimally Invasive Plate Osteosynthesis in Three Dogs

The Minimally Invasive Reduction Instrumentation System (MIRIS) was utilized to facilitate minimally invasive plate osteosynthesis (MIPO) of distal limb diaphyseal comminuted fractures (2 crural, 1 antebrachial) in three dogs. The MIRIS facilitated efficient MIPO in all three fractures. Radial and tibial lengths were restored within 2% of the length of the intact bone and postoperative frontal and sagittal plane angulation were within 3° of the normal contralateral limb for each of the fractures. Fixation failed in one of the tibial fractures when the plates bent a week following surgery. The implants were removed and the fracture was restabilized via MIPO facilitated by the MIRIS. Inappropriate implant selection was considered the primary reason for implant failure. All three fractures achieved union by 10 weeks following surgery. The dog that underwent revision surgery developed a surgical site infection 5 months following revision surgery, which necessitated implant removal. All three dogs had excellent limb function at the time of the final evaluation. This system resulted in reductions that were near anatomic, with acceptable restoration of length and alignment and excellent limb function.

Management of feline tibial diaphyseal fractures using orthogonal plates performed via minimally invasive plate osteosynthesis

Objectives The objective was to assess the medium- and long-term outcomes (radiographic and owner questionnaire) of feline tibial diaphyseal fractures with orthogonal plate fixation via a minimally invasive plate osteosynthesis (MIPO) approach. Methods Medical records and radiographs of cats that had tibial diaphyseal fractures stabilised with orthogonal plates were obtained (2012-2016). Immediate postoperative radiographs were reviewed to assess the construct configuration and follow-up radiographs (where available) were used to assess bone healing and implant-related complications. An owner-completed questionnaire (feline musculoskeletal pain index [FMPI]) was used at a minimum of 6 months following surgery to assess the cats' ability to perform normal activities. Results Eight feline tibial diaphyseal fractures met the inclusion criteria. One major complication was observed, most likely due to an operative technical error. There were no further complications following revision surgery. Six of the eight cases that had radiographic follow-up either had clinical bone union or showed evidence of bone healing. All cases were classified as successful according to FMPI. Conclusions and relevance Orthogonal plating of feline tibial diaphyseal fractures via an MIPO approach resulted in successful outcomes and a lower complication rate compared with previously reported techniques.

Handling of the tibial muscle envelope in tibial plateau levelling osteotomy - to elevate or not?

Objective: To compare the outcome of the tibial plateau levelling osteotomy (TPLO) procedure, using a 6-hole 3.5 mm locking TPLO plate and performed with the muscle elevation technique (ET) and placement of sponges, to the TPLO without performing these steps (non-elevation-technique [NET]).

Material and methods: Medical records and radiographs of dogs with ET (n = 21) or NET (n = 19) were retrospectively reviewed. Signalment, TPLO procedure side, meniscal treatment, surgery time, haemorrhage, preand postoperative tibial plateau angle, assistant, amount of rehabilitation, bone healing (cortical, osteotomy, combined healing scores), complications, limb function, recovery time and follow-up were recorded and analysed using multivariate analysis. A value of p <0.05 was considered significant.

Results: Surgery time was significantly shorter with the NET (68.5 min ± 3.4) than with the ET (87.8 min ± 3.4) (p <0.01). No significant differences were detected for all other evaluated factors. Soft tissue trauma was minimal and none of the dogs suffered severe haemorrhage. The bone healing scores with the NET and the ET were not significantly different (p = 0.1, p = 0.2, p = 0.1). Complications were rare, minor and not significantly different between groups (p = 0.73).

Clinical relevance: The results of this in vivo study indicate that NET is a feasible technique that can be considered for the clinical setting.

Complications of appendicular fracture repair in cats and small dogs using locking compression plates

Objective: Our objectives were: 1) to review the complications associated with stabilization of appendicular fractures in cats and small dogs using locking compression plates (LCP), and 2) to identify factors that could influence fixation construct stability.

Study design: Retrospective clinical study.

Materials and methods: Medical and radiographic records of cats and small dogs with appendicular fractures treated with LCP were reviewed. Only cases with adequate follow-up to document clinical union and cases for which complications appeared before the clinical union were included. Complications were classified as implant-related complications or other complications. Cases with implant-related complications were compared to cases with non-implant-related complications for differences in signalment (species, age, body weight, multiple fractures), fracture location and type (fractured bone, fracture localization, closed or open fracture), reduction method (open reduction and internal fixation [ORIF] or minimally invasive plate osteosynthesis [MIPO]) and fixation evaluations (implant size, platebridging ratio, plate span ratio, working length, plate screw density, number of screws and cortices engaged per plate and per main fragment, ratio between screw and bone diameter at the narrowest aspect of the bone, and presence of ancillary fixation).

Results: Seventy-five fractures from 63 cats (64 fractures) and 10 dogs (11 fractures) met the inclusion criteria. Eight humeral, 13 radio-ulnar, 26 femoral, and 28 tibio-fibular fractures were treated. Primary repair of the fracture was performed using 2.0 mm and 2.4 mm LCP in 22 and 53 fractures, respectively. Overall and implant-related complications were encountered in 13 and seven of 75 fractures, respectively. Fixation failure was not significantly associated with any aforementioned factor considered in this study, and in particular, there was no significant difference in the occurrence of fixation failure between fractures stabilized with two, or more than two, bicortical locking screws per main fragment.

Clinical significance: 2.0 mm and 2.4 mm LCP were used to manage appendicular fractures in cats and small dogs. The overall complication and fixation failure rate were comparable to those reported in previous studies in which various locking plate systems were used.

Online Supplementary Material for this article is available at: http://dx.doi.org/10.3415/VCOT-14-09-0146

Biomechanical comparison of a 3.5-mm conical coupling plating system and a 3.5-mm locking compression plate applied as plate-rod constructs to an experimentally created fracture gap in femurs of canine cadavers

OBJECTIVE To compare stiffness and resistance to cyclic fatigue of two 3.5-mm locking system plate-rod constructs applied to an experimentally created fracture gap in femurs of canine cadavers. SAMPLE 20 femurs from cadavers of 10 mixed-breed adult dogs. PROCEDURES 1 femur from each cadaver was stabilized with a conical coupling plating system-rod construct, and the contralateral femur was stabilized with a locking compression plate (LCP)-rod construct. An intramedullary Steinmann pin was inserted in each femur. A 40-mm gap then was created; the gap was centered beneath the central portion of each plate. Cyclic axial loading with increasing loads was performed. Specimens that did not fail during cyclic loading were subjected to an acute load to failure. RESULTS During cyclic loading, significantly more LCP constructs failed (6/10), compared with the number of conical coupling plating system constructs that failed (1/10). Mode of failure of the constructs included fracture of the medial or caudal aspect of the cortex of the proximal segment with bending of the plate and pin, bending of the plate and pin without fracture, and screw pullout. Mean stiffness, yield load, and load to failure were not significantly different between the 2 methods of stabilization. CONCLUSIONS AND CLINICAL RELEVANCE Both constructs had similar biomechanical properties, but the conical coupling plating system was less likely to fail than was the LCP system when subjected to cyclic loading. These results should be interpreted with caution because testing was limited to a single loading mode.

Intraoperative use of a transarticular circular fixator construct to facilitate reduction and stabilisation of a proximal tibial physeal fracture in a dog

CASE REPORT

A 4-month-old female intact American Pit Bull Terrier was presented for right pelvic limb lameness 1 day after the dog had been hit by an all-terrain vehicle. Orthogonal radiographs of the right stifle revealed a Salter-Harris type IV fracture through the proximal tibial physis extending caudodistally through the proximal tibial metaphysis. The distal tibia was markedly displaced cranially, laterally and proximally, resulting in complete overriding of the fracture segments. An open approach was made in order to facilitate direct reduction, but the fracture could not be sufficiently distracted and the epiphyseal segment remained fixed caudal to the remainder of the tibia. Concerns regarding possible iatrogenic trauma to the epiphysis prompted the use of a transarticular circular fixator construct to distract the fracture segments to facilitate reduction. Distraction that facilitated reduction was performed using three TrueLok Rapid Quick Adjust Struts that were positioned between the two ring components. The struts also allowed for multiplanar adjustment of alignment, which allowed the fracture to be maintained in anatomic reduction as divergent interfragmentary Kirschner wires were placed. Radiographic union was confirmed 19 days after surgery.

CONCLUSION/CLINICAL SIGNIFICANCE

Transient intraoperative application of a circular construct incorporating the TrueLok components facilitated accurate fracture reduction without inflicting further iatrogenic trauma to the epiphysis, after traditional direct reduction techniques proved ineffective, and afforded a successful clinical outcome in the dog reported here.

Outcome and complications in dogs with appendicular primary bone tumors treated with stereotactic radiotherapy and concurrent surgical stabilization

OBJECTIVE

To document the outcome of dogs with appendicular primary bone tumors treated with stereotactic radiotherapy (SRT) and concurrent stabilization.

STUDY DESIGN

Multi-institutional retrospective case series.

ANIMALS

Eighteen dogs with presumptive or definitive diagnosis of appendicular osteosarcoma.

METHODS

Medical records of dogs with appendicular primary bone tumors treated with SRT and stabilization were reviewed for signalment, preoperative staging and diagnostics, radiation dose, stabilization method, and outcome.

RESULTS

The distal radius was affected in 13/18 cases. Osteosarcoma or sarcoma was confirmed cytologically or histologically in 15/18 cases. Seven dogs were diagnosed with a pathological fracture at the time of treatment, and 11 were considered at high risk for pathological fracture. Dogs received a single dose (n = 5) or 3 doses (n = 13) of SRT. Surgical stabilization was performed under the same anesthetic event as the final dose of SRT in 10 dogs. Stabilization was achieved with a bone plate (n = 15) or interlocking nail (n = 3). Seventeen dogs received adjuvant chemotherapy. Complications occurred in 16/17 dogs, 15/17 of those being considered major complications. Four dogs experienced more than one complication. Infection was the most common complication, diagnosed in 15/17 cases, and considered as a major complication in 13/15 cases. Postoperative fracture was recorded as a major complication in 3 cases. Nine dogs were amputated at a median of 152 days. The median survival time was 344 days.

CONCLUSION

Treatment of bone tumors with SRT and concurrent stabilization was associated with a prohibitively high complication rate in dogs. Alternative methods for limb salvage should be considered for dogs at risk for pathologic fracture.

Osteossíntese minimamente invasiva com placa bloqueada (Mipo) sem a utilização de intensificadores de imagem nas fraturas de tíbia em cães

RESUMO Avanços na compreensão da biologia óssea e das complicações das fraturas têm levado a modificações na abordagem da fixação interna, sendo a osteossíntese minimamente invasiva com placa (Mipo) uma das recentes evoluções para o manejo biológico das fraturas. O objetivo do presente estudo foi avaliar o uso de placas bloqueadas aplicadas de forma minimante invasivas em fraturas da tíbia de cães, sem a utilização de intensificadores de imagem intraoperatória. Foram utilizados 10 cães que apresentavam fraturas da tíbia, de idades e raças variadas. Os animais foram avaliados quanto à deambulação, à intensidade do edema, e exames radiográficos foram realizados nos períodos zero, 15, 30, 60, 90 e 120 dias de pós-operatório. Após 15 dias de pós-operatório, 80% dos cães já utilizavam o membro ao caminhar e apresentavam formação de edema discreto a ausente no membro operado. Após 30 dias de pós-operatório, todos os cães já apoiavam o membro ao caminhar e não apresentavam formação de edema. Todos os pacientes apresentaram sinais radiográficos de início de consolidação óssea após 15 dias de pós-operatório e pôde-se observar que a união clínica ocorreu em média aos 42,5 dias. O tratamento de fraturas de tíbia por meio da Mipo é alternativa eficaz, resultando em utilização precoce do membro e união clínica efetiva, e pode ser realizado sem uso de intensificadores de imagem.

The impact of surgical timing and intervention on outcome in traumatized dogs and cats

OBJECTIVE

To review the relevant human and veterinary literature regarding the timing of surgical intervention for trauma patients and the impact on outcome.

DATA SOURCES

Original research, clinical studies, and review articles with no date restrictions from both human and veterinary literature.

HUMAN DATA SYNTHESIS

Despite extensive research into the ideal timing of surgical intervention for human trauma victims, debate is ongoing and views are still evolving. Prior to the 1970s, the standard of care consisted of delayed surgical treatment, as these patients were considered too ill to undergo surgery. Beginning in the 1970s, and continuing for nearly 2 decades, early definitive surgical treatment was recommended. The most recent evolution of human trauma management incorporates the concept of damage control surgery, which acknowledges the importance of early skeletal stabilization or laparotomy for reducing morbidity while attempting to avoid complications such as acute respiratory distress syndrome or multiple organ dysfunction syndrome.

VETERINARY DATA SYNTHESIS

Despite a relatively large amount of literature available regarding veterinary trauma, no evidence exists to provide the clinician guidance as to the ideal timing of surgery for trauma patients. With the exception of diaphragmatic hernia, no studies were identified that attempted to evaluate this variable.

CONCLUSIONS

Veterinary-specific studies are needed to evaluate the impact of surgical timing on outcome following trauma. The information that can be obtained from studies in this area can improve veterinary trauma care and may be used as models for human trauma care through translational applications.

Experimental analysis of the minimally invasive plate osteosynthesis technique applied with non-locking screws and screw locking elements

Minimally invasive plate osteosynthesis (MIPO) is an effective surgical technique in the repair of humeral and tibial shaft fractures. There is some controversy as to the minimum number of screws required to ensure correct stability to promote healing, especially when dealing with low quality bones. This work compared different systems assembled on synthetic models simulating a comminuted fracture. Group 1 comprised a locking compression plate with four non-locking screws placed at the holes furthest from the fracture. Group 2 differed from group 1 only in the additional use of two screw locking elements (SLE). Group 3 had four rather than two SLE and, finally, Group 4 used 4 locking screws. The compression and torsion tests with static and cyclic loads showed that, in MIPO, two locking screws or two non-locking screws with SLE could be used per segment without any significant loss in stiffness after 1000 cycles, with system stability guaranteed in both cases. However, lower strength and significant loss of stiffness were observed when non-locking screws were used alone.