Sharon C Kerwin

Texas A&M University, College Station, Texas, United States

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Publications (60)84.39 Total impact

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    ABSTRACT: Background Cerebrospinal fluid (CSF) is commonly acquired in dogs with intervertebral disk herniation (IVDH) and is a common method to assess inflammatory responses following spinal cord injury (SCI).Objectives The purpose of the study was to describe relationships between cisternal CSF characteristics, behavioral measures of SCI, T2- weighted (T2W) hyperintensity on magnetic resonance imaging (MRI), and long-term outcome in dogs with IVDH. Diagnostic accuracy of CSF for differentiating IVDH from other myelopathies was also assessed.Methods The retrospective case series included 727 dogs, 443 with thoracolumbar IVDH, 103 with cervical IVDH, and 181 with other spinal cord diseases. Signalment, initial neurologic function, ambulatory function at long-term follow-up, T2W MRI, and CSF variables were recorded for dogs with IVDH. Signalment, etiology, and CSF data were retrieved for dogs with other myelopathies. Associations between CSF predictors, diagnosis, and outcomes were assessed.ResultsCSF total nucleated cell count (TNCC) increased with SCI severity (rho −0.256, P < .001) in dogs with IVDH, TNCC was significantly higher in the presence of T2W hyperintensity (P = .001) in dogs with thoracolumbar IVDH, but TNCC, RBC count, microprotein, and percent neutrophils decreased with increasing injury duration (rho −0.253, P < .001; rho −0.269, P < .001; rho −0.141, P = .004, and rho −0.356, P < .001, respectively). CSF characteristics were not accurate for differentiating IVDH from other spinal cord diseases.Conclusions In dogs with IVDH, CSF TNCC, RBC count, microprotein, and percent neutrophils are correlated with clinical aspects of SCI such as injury severity and duration, but cannot differentiate IVDH from other etiologies.
    Veterinary Clinical Pathology 06/2014; · 1.29 Impact Factor
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    ABSTRACT: Canine intervertebral disk herniation (IVDH) is a common, naturally-occurring form of spinal cord injury (SCI) which is increasingly being used in pre-clinical evaluation of therapies. Although IVDH bears critical similarities to human SCI with respect to lesion morphology, imaging features, and post-SCI treatment, limited data are available concerning secondary injury mechanisms. Here, we characterized cerebrospinal fluid (CSF) cytokines and chemokines in dogs with acute, surgically treated, thoracolumbar IVDH (n=39) and healthy control dogs (n=21) to investigate early inflammatory events following SCI. A bioplex system was used to measure interleukin-2, -6, -7, -8, -10, -15, -18, granulocyte macrophage colony stimulating factor (GM-CSF), interferon gamma (IFN-γ), keratinocyte chemoattractant-like (KC-like) protein, IFN-γ-inducible protein-10 (IP-10), monocyte chemotactic protein-1 (MCP-1) and tumor necrosis factor alpha (TNF-α). Cytokine and chemokine concentrations in the CSF of healthy and SCI dogs were compared and in SCI dogs were correlated to the duration of SCI, behavioral measures of injury severity at the time of sampling, and neurologic outcome 42 days post-SCI as determined by a validated ordinal score. IL-8 concentration was significantly higher in SCI cases than healthy controls (P = 0.0013) and was negatively correlated with the duration of SCI (P=0.042). CSF MCP-1 and KC-like protein were positively correlated with CSF microprotein concentration in dogs with SCI (P <0.0001 and P=0.004). CSF MCP-1 concentration was negatively associated with 42-days post-injury outcome (P<0.0001). Taken together, these data indicate that cytokines and chemokines present following SCI in humans and rodent models are associated with SCI pathogenesis in canine IVDH.
    Journal of neurotrauma 04/2014; · 4.25 Impact Factor
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    ABSTRACT: To compare the biomechanical properties of clamp rod internal fixation (CRIF)/rod and LC-DCP/rod constructs in a canine femoral gap model. Cadaveric biomechanical study. Canine femora (n = 10 pair). Femora with 40 mm ostectomies were assigned to LC-DCP/rod or CRIF/rod treatment groups. Five construct pairs had 4-point bending and 5 pairs had torsional loading. Construct stiffness, strength, and bending angle at failure or permanent angular deformation (torsional loading) were determined. Statistical comparisons were performed using Student t tests; significance was set at P ≤ .05. There was significantly greater permanent angular deformation, or residual twist, in the CRIF/rod constructs (23.1 ± 0.89°) compared with LC-DCP/rod constructs (7.47 ± 2.08°). Whereas there was no significant difference in torsional stiffness of these constructs at torsional loads <4.92 N m (P = .819), LC-DCP/rod constructs had significantly greater torsional stiffness (0.303 ± 0.079 N m/°) and strength (11.546 ± 2.79 N m) than CRIF/rod construct stiffness (0.06 ± 0.013 N m/°) and strength (6.078 ± 0.527 N m) at torsional loads >4.92 N m. Differences in stiffness and strength in 4-point bending were not statistically significant. LC-DCP/rod constructs had significantly less permanent angular deformation than CRIF/rod constructs. CRIF/rod constructs became less stiff as torsional load was increased, thus the LC-DCP/rod constructs had significantly greater torsional stiffness and strength under high torsional loads. LC-DCP/rod and CRIF/rod constructs performed similarly under 4-point bend loading conditions.
    Veterinary Surgery 01/2014; · 1.24 Impact Factor
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    ABSTRACT: To report thoracic limb alignment values in healthy dogs; to determine if limb alignment values are significantly different when obtained from standing versus recumbent radiographic projections. Prospective cross-sectional study. Labrador Retrievers (n = 45) >15 months of age. Standing and recumbent radiographs were obtained and limb montages were randomized before analysis by a single investigator blinded to dog, limb, and limb position. Twelve limb alignment values were determined using the CORA methodology. Measurements were performed in triplicate and intra-observer variability was evaluated by intra-class correlation coefficient (ICC). Limb alignment values were reported as mean ± SD and 95% confidence intervals. Linear mixed models were used to determine if significant associations existed between limb alignment values and limb, limb position, gender, age, weight, and body condition score. There were significant differences in standing and recumbent limb alignment values for all values except elbow mechanical axis deviation (eMAD). Limb, gender, age, body weight, and body condition score had no effect. ICC values ranged from 0.522 to 0.758, indicating moderate to substantial agreement for repeated measurements by a single investigator. Limb alignment values are significantly different when determined from standing versus recumbent radiographs in healthy Labrador Retrievers.
    Veterinary Surgery 01/2014; · 1.24 Impact Factor
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    ABSTRACT: Susceptibility artifacts caused by ferromagnetic implants compromise magnetic resonance imaging (MRI) of the canine stifle after tibial plateau leveling osteotomy (TPLO) procedures. The WARP-turbo spin echo sequence is being developed to mitigate artifacts and utilizes slice encoding for metal artifact reduction. The aim of the current study was to evaluate the WARP-turbo spin echo sequence for imaging post TPLO canine stifle joints. Proton density weighted images of 19 canine cadaver limbs were made post TPLO using a 3 Tesla MRI scanner. Susceptibility artifact sizes were recorded and compared for WARP vs. conventional turbo spin echo sequences. Three evaluators graded depiction quality for the tibial tuberosity, medial and lateral menisci, tibial osteotomy, and caudal cruciate ligament as sufficient or insufficient to make a diagnosis. Artifacts were subjectively smaller and local structures were better depicted in WARP-turbo spin echo images. Signal void area was also reduced by 75% (sagittal) and 49% (dorsal) in WARP vs. conventional turbo spin echo images. Evaluators were significantly more likely to grade local anatomy depiction as adequate for making a diagnosis in WARP-turbo spin echo images in the sagittal but not dorsal plane. The proportion of image sets with anatomic structure depiction graded adequate to make a diagnosis ranged from 28 to 68% in sagittal WARP-turbo spin echo images compared to 0-19% in turbo spin echo images. Findings indicated that the WARP-turbo spin echo sequence reduces the severity of susceptibility artifacts in canine stifle joints post TPLO. However, variable depiction of local anatomy warrants further refinement of the technique.
    Veterinary Radiology &amp Ultrasound 01/2014; · 1.41 Impact Factor
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    ABSTRACT: Matrix metalloproteinase-9 is elevated within the acutely injured murine spinal cord and blockade of this early proteolytic activity with GM6001, a broad-spectrum matrix metalloproteinase inhibitor, results in improved recovery after spinal cord injury. As matrix metalloproteinase-9 is likewise acutely elevated in dogs with naturally occurring spinal cord injuries, we evaluated efficacy of GM6001 solubilized in dimethyl sulfoxide in this second species. Safety and pharmacokinetic studies were conducted in naïve dogs. After confirming safety, subsequent pharmacokinetic analyses demonstrated that a 100 mg/kg subcutaneous dose of GM6001 resulted in plasma concentrations that peaked shortly after administration and were sustained for at least 4 days at levels that produced robust in vitro inhibition of matrix metalloproteinase-9. A randomized, blinded, placebo-controlled study was then conducted to assess efficacy of GM6001 given within 48 hours of spinal cord injury. Dogs were enrolled in 3 groups: GM6001 dissolved in dimethyl sulfoxide (n = 35), dimethyl sulfoxide (n = 37), or saline (n = 41). Matrix metalloproteinase activity was increased in the serum of injured dogs and GM6001 reduced this serum protease activity compared to the other two groups. To assess recovery, dogs were a priori stratified into a severely injured group and a mild-to-moderate injured group, using a Modified Frankel Scale. The Texas Spinal Cord Injury Score was then used to assess long-term motor/sensory function. In dogs with severe spinal cord injuries, those treated with saline had a mean motor score of 2 (95% CI 0-4.0) that was significantly (P<0.05; generalized linear model) less than the estimated mean motor score for dogs receiving dimethyl sulfoxide (mean, 5; 95% CI 2.0-8.0) or GM6001 (mean, 5; 95% CI 2.0-8.0). As there was no independent effect of GM6001, we attribute improved neurological outcomes to dimethyl sulfoxide, a pleotropic agent that may target diverse secondary pathogenic events that emerge in the acutely injured cord.
    PLoS ONE 01/2014; 9(5):e96408. · 3.53 Impact Factor
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    ABSTRACT: Study Design. Laboratory investigation, ex vivo.Objective. Post-operative complications are common following spinal implantation procedures and magnetic resonance imaging (MRI) would be the ideal modality to image these patients. Unfortunately, the implants cause artifacts that can render MRI non-diagnostic. The WARP-Turbo Spin Echo (TSE) sequence has been developed to mitigate artifacts caused by metal. The objective of this investigation was to evaluate the performance of the WARP-TSE sequence in canine cadaver specimens following implantation with metallic vertebral implants.Summary of Background Data. Magnetic field strength, implant type, and MRI acquisition technique all play a role in the severity of susceptibility artifacts. The WARP-TSE sequence utilizes increased bandwidth, view angle tilting (VAT), and slice-encoding metal artifact correction (SEMAC) to correct for susceptibility artifact. The WARP-TSE technique has outperformed conventional techniques in patients following total hip arthroplasty. However, published reports of its application in subjects with vertebral column implants are lacking.Methods. Ex vivo anterior stabilization of the atlantoaxial joint was performed in six adult small breed (<8 kg) cadaver dogs using stainless steel screws and polymethylmethacrylate. Axial and sagittal T2-weighted and short tau inversion recovery (STIR) MRI was performed utilizing conventional pulse sequences and WARP-TSE sequences at 3 tesla. Images were assessed qualitatively and quantitatively.Results. Images made with the WARP TSE sequence had smaller susceptibility artifacts and superior spinal cord margin depiction. WARP-TSE sequences reduced the length over which susceptibility artifacts caused spinal cord margin depiction interference by 24.9%-71.5% with scan times of approximately 12-16 minutes.Conclusion. The WARP-TSE sequence is a viable candidate for evaluating the vertebral column following implantation with stainless steel implants.
    Spine 08/2013; · 2.16 Impact Factor
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    ABSTRACT: Validated spinal cord injury (SCI) scores have been established for veterinary species but are not uniformly used in practice. To determine the level of agreement of SCI scores at the time of admission versus those assigned from reconstructed medical records in a population of dogs with intervertebral disk herniation (IVDH). Eighty-six client-owned dogs with confirmed IVDH. Retrospective study. Medical records were reviewed for history, physical examination, neurologic examination, and recorded Modified Frankel score (MFS) and Texas spinal cord injury score (TSCIS) at the time of admission. Three raters, all board-certified neurologists, assigned MFS and TSCIS based on digitized abstracted medical records to each patient. These scores were then compared to the recorded score at the time of admission. Actual agreement for MFS and TSCIS derived from medical records by the 3 raters compared to prospectively derived MFS and TSCIS was 77.9 and 51.2%, respectively. A kappa value of 0.572 (95% CI 0.450, 0.694; P < .001) and an ICC of 0.533 (95% CI 0.410, 0.646; P < .001) were calculated for MFS scores. A kappa value of 0.100 (95% CI 0.000, 0.222; P = .107), and an ICC of 0.503 (95% CI 0.377, 0.620; P < .001) were calculated for TSCIS scores. Results showed that SCI scores recorded at the time of admission often do not agree with those retrospectively abstracted from medical records. Agreement was less when using the more complex TSCIS scale and therefore the MFS scale might be more appropriate for use in retrospective studies.
    Journal of Veterinary Internal Medicine 07/2013; · 2.06 Impact Factor
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    ABSTRACT: To examine associations between CSF biomarkers, initial neurologic dysfunction, and long-term ambulatory outcome in dogs with acute intervertebral disk herniation (IVDH). Prospective clinical study. 54 dogs with acute thoracolumbar IVDH and 16 clinically normal dogs. For each dog, variables, including CSF myelin basic protein (MBP), lactate, calcium, glucose, and total protein concentrations; nucleated cell count; and creatine kinase (CK) and aspartate aminotransferase activities, were measured. For dogs with thoracolumbar IVDH, initial neurologic function was characterized by use of a modified Frankel score (MFS; determined on a scale of 0 to 5, where 0 represented paraplegia with no deep nociception and 5 represented paraspinal hyperesthesia only). Long-term follow-up was assessed. Among dogs with thoracolumbar IVDH, those with CSF CK activity ≤ 38 U/L had a 35-fold increase in the odds of long-term ambulation, compared with the odds in dogs with CSF CK activity > 38 U/L, adjusting for neurologic functioning at the evaluation. The CSF lactate, calcium, and glucose concentrations and aspartate aminotransferase activity were not predictive of long-term ambulatory outcome. Data analysis revealed that long-term functional recovery was > 98% for affected dogs, regardless of their initial MFS, when CSF CK activity was ≤ 38 U/L and MBP concentration was ≤ 3 ng/mL. In dogs with acute thoracolumbar IVDH, CSF CK activity and MBP concentration appeared to be prognostic indicators and, along with initial MFS, can be used to predict long-term ambulatory outcome.
    Journal of the American Veterinary Medical Association 03/2012; 240(5):555-62. · 1.72 Impact Factor
  • Sharon Kerwin
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    ABSTRACT: PATIENT GROUP: The majority of cats will develop radiographic evidence of degenerative joint disease by the time they are 12 years of age, and many will suffer from a decline in quality of life associated with undiagnosed and untreated orthopedic disease. PRACTICAL RELEVANCE: A focused, efficient orthopedic examination, including gait observation and palpation (awake and under sedation), supplemented with appropriate history, is key in ruling in, or out, clinically important musculoskeletal disease. Identifying problems assists in both developing a diagnostic plan and monitoring response to treatment. CLINICAL CHALLENGES: Many clinicians feel uncomfortable in their ability to reliably perform an orthopedic examination in the cat, and diagnosis and evaluation of response to treatment in cats with orthopedic disease can be challenging. Hands-on training in feline orthopedic examination is limited in many veterinary curricula. Additional constraints may include failure to obtain important information in the history that indicates feline orthopedic disease, lack of appropriate facilities in which to conduct a complete orthopedic examination, and inability to obtain the most important information during the time available to conduct the examination. These problems can create gaps in the practitioner's ability to provide excellent care for a large proportion of the feline population. GOALS: The above challenges can mostly be overcome with advanced planning and with consideration of the unique behavioral aspects related to feline handling. As discussed in this review, the aim of the initial orthopedic examination is to localize the problem to a specific limb, ideally to a region or joint of the limb, which can further direct diagnostics such as radiography or arthrocentesis. This should provide a basis for follow-up and assessment of whether treatment strategies are effective.
    Journal of feline medicine and surgery. 01/2012; 14(1):6-12.
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    ABSTRACT: OBJECTIVE: To report findings and outcomes of dogs with reherniation of nuclear material within 7 days of hemilaminectomy for acute thoracolumbar (TL) intervertebral disk extrusion. STUDY DESIGN: Retrospective case series. ANIMALS: Chondrodystrophic dogs (n = 11). METHODS: Dogs with acute neurologic decline within 1 week of surgical decompression for TL disk extrusion were identified. Advanced imaging was used to document extradural spinal cord compression at the previous surgery site. Ten dogs had a 2nd decompressive surgery to remove extruded nuclear material. RESULTS: All dogs had acute neurologic deterioration (average, 2 neurologic grades) 2-7 days after initial hemilaminectomy. Computed tomography (CT; n = 10) or myelography (n = 1) documented extradural spinal cord compression compatible with extruded disk material at the previous hemilaminectomy site. Dogs that had a 2nd surgical decompression improved neurologically within 24 hours and were paraparetic at discharge. The single dog that did not have decompressive surgery did not regain deep nociception during 185-day follow-up. CONCLUSIONS: Early reherniation at the site of previous hemilaminectomy can produce acute deterioration of neurologic function and should be investigated with diagnostic imaging. Repeat decompressive surgery can lead to functional recovery.
    Veterinary Surgery 11/2011; · 1.24 Impact Factor
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    ABSTRACT: To determine the lowest efficacious dose of oral meloxicam for relieving pain in cats with a sodium urate (SU)-induced acute inflammatory synovitis. Randomized, blinded, controlled, and four-way crossover study. Eight surgically neutered cats (four males, four females) paired according to sex. Each pair of cats was treated with 0 (placebo), 0.025, 0.05, or 0.075 mg kg(-1) oral meloxicam once daily for 4 days prior to injection, into alternating stifles, of 1 mL of 20 mg mL(-1) SU crystals, beginning with the right stifle. Each cat received each of the four treatments, separated by at least 21 days. Analgesic efficacy was evaluated based on objective (e.g., pressure mat data total force, contact pressure, and contact area) and subjective (e.g., scores for Analgesia Scale [AS], Lameness Scale [LS], and Visual Analog Scale [VAS]) outcome measures for pain assessment. All outcome measures were recorded before and during 30 hours after SU injection. The pre-defined primary outcome measure was the area under the response-time curve (AUC(0-30) hours) of the total force of the injected limb. Data were analyzed by analysis of variance. A sequential test procedure was applied and the test sequence stopped in case of a nonsignificant result. Meloxicam at doses of 0.05 and 0.075 mg kg(-1) day(-1) PO was significantly different from placebo for the pre-defined primary outcome measure (i.e., AUC(0-30) hours of total force). All tested meloxicam doses were lower than placebo for the subjective outcome measures (i.e., AUC(0-30) hours of AS, LS, and VAS). The lowest efficacious dose of meloxicam for relieving pain in cats with an SU-induced synovitis was 0.05 mg kg(-1) day(-1) PO according to the pre-defined primary outcome measure. However, lower doses may also be effective as seen in the subjective outcome measures.
    Veterinary Anaesthesia and Analgesia 07/2011; 38(4):394-406. · 1.34 Impact Factor
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    ABSTRACT: Magnetic resonance (MR) imaging and histopathology were used to diagnose an articular process synovial myxoma in a dog. On MR images, the tumor was characterized by distortion of the left L1-L2 articular process, widening of the articular process joint, and the presence of a mass contiguous with the synovium of the articular process that displaced the spinal cord. The tumor was T2-hyperintense, T1-hypointense, relative to muscle, and had mild contrast enhancement. The MR features of articular process synovial myxoma may be distinct from other diseases of the articular process joint.
    Veterinary Radiology &amp Ultrasound 01/2011; 52(3):309-12. · 1.41 Impact Factor
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    Sharon C Kerwin
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    ABSTRACT: Osteoarthritis is a common radiographic finding in older cats, with a prevalence of up to 90% in appendicular joints. Many cats experience impaired mobility from osteoarthritis; however, there are more and more treatment options available, including diet modification, environmental modification, medical therapy, and physical rehabilitation. Continuing challenges involve accurate diagnosis and outcome assessment of treatment, but considerable progress has been made in the last decade.
    Topics in Companion Animal Medicine 11/2010; 25(4):218-23. · 0.93 Impact Factor
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    ABSTRACT: Release of myelin basic protein (MBP) into the cerebrospinal fluid (CSF) is associated with active demyelination and correlates with outcome in various neurological diseases. To describe associations among CSF MBP concentration, initial neurological dysfunction, and long-term ambulatory outcome in dogs with acute thoracolumbar intervertebral disk herniation (IVDH). Fifty seven [corrected] dogs with acute thoracolumbar IVDH and 16 clinically normal dogs. Prospective case series clinical study. Signalment, initial neurological dysfunction as determined by a modified Frankel score (MFS), and ambulatory outcome at >3-month follow-up were recorded. Cisternal CSF MBP concentration was determined by an ELISA. Associations were estimated between CSF MBP concentration and various clinical parameters. Dogs with thoracolumbar IVDH that did not ambulate at follow-up had a higher CSF MBP concentration (median, 3.56 ng/mL; range, 0.59-51.2 ng/mL) compared with control dogs (median, 2.22 ng/mL; range, 0-3.82 ng/mL) (P=.032). A CSF MBP concentration of >or=3 ng/mL had a sensitivity of 78% and specificity of 76% to predict an unsuccessful outcome based on receiver-operating characteristics curve analysis (area under the curve=0.688, P=.079). Affected dogs with a CSF MBP concentration>or=3 ng/mL had 0.09 times the odds of ambulation at follow-up compared with affected dogs with CSF MBP concentration<3 ng/mL when adjusted for initial MFS (95% confidence interval 0.01-0.66, P=.018). These results would suggest that CSF MBP concentration may be useful as an independent prognostic indicator in dogs with thoracolumbar IVDH.
    Journal of Veterinary Internal Medicine 05/2010; 24(4):890-6. · 2.06 Impact Factor
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    ABSTRACT: To compare the accuracy of radiography and computed tomography (CT) in predicting implant position in relation to the vertebral canal in the cervical and thoracolumbar vertebral column. In vitro imaging and anatomic study. Medium-sized canine cadaver vertebral columns (n=12). Steinmann pins were inserted into cervical and thoracolumbar vertebrae based on established landmarks but without predetermination of vertebral canal violation. Radiographs and CT images were obtained and evaluated by 6 individuals. A random subset of pins was evaluated for ability to distinguish left from right pins on radiographs. The ability to correctly identify vertebral canal penetration for all pins was assessed both on radiographs and CT. Spines were then anatomically prepared and visual examination of pin penetration into the canal served as the gold standard. Left/right accuracy was 93.1%. Overall sensitivity of radiographs and CT to detect vertebral canal penetration by an implant were significantly different and estimated as 50.7% and 93.4%, respectively (P<.0001). Sensitivity was significantly higher for complete versus partial penetration and for radiologists compared with nonradiologists for both imaging modalities. Overall specificity of radiographs and CT to detect vertebral canal penetration was 82.9% and 86.4%, respectively (P=.049). CT was superior to radiographic assessment and is the recommended imaging modality to assess penetration into the vertebral canal. CT is significantly more accurate in identifying vertebral canal violation by Steinmann pins and should be performed postoperatively to assess implant position.
    Veterinary Surgery 04/2010; 39(6):680-7. · 1.24 Impact Factor
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    ABSTRACT: Introduction: Diaphyseal fractures of the radius and ulna are common orthopedic injuries in dogs. As these fractures are often secondary to automobile accidents, they are frequently comminuted and difficult to anatomically reconstruct. As such, these injuries lend themselves to management with indirect reduction techniques. The objectives of this study are to describe a minimally invasive plate-rod (MIPR) technique in diaphyseal radius and ulna fractures and present the outcome in a series of cases treated by this method. Materials and Methods: Medical records (November 2005-June 2009) of 8 dogs with diaphyseal radius and ulna fractures stabilized by a MIPR construct were reviewed. Data retrieved included signalment, weight, limb affected, cause of injury, open vs. closed fracture, number of fragments, implant size, number of screws used and cortices engaged, number of open screw holes, operative time, complications and final outcome. Results: Dogs with diaphyseal radius and ulna fractures were treated with minimally invasive plate-rod constructs. All fractures were due to trauma and 2 fractures were open. Complications included osteomyelitis associated with the ulnar pin (n = 1). Osteomyelitis resolved with pin removal and healing occurred in all cases with no implant failures. Median time to radiographic union was 10.5 weeks. Discussion/Conclusion: Use of MIPR constructs on diaphyseal fractures of the radius and ulna is an effective technique for managing these fractures using principles of biological osteosynthesis. An intramedullary rod in the ulna assists with fracture reduction and stabilization and rod removal is recommended once fracture healing has occurred. Acknowledgments: Thank you to the residents at TAMU that contributed these cases.
    Annual Conference Veterinary Orthopedic Society; 02/2010
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    ABSTRACT: To describe a surgical technique for placement of a minimally invasive radial plate following application of an ulnar rod (MIPR) for treatment of antebrachial fractures. Medical records (November 2005-June 2009) were searched to identify dogs with diaphyseal radius and ulna fractures stabilised by MIPR. Data retrieved included signalment, weight, limb affected, cause of injury, open versus closed fracture, number of fragments, implant size, number of screws used and cortices engaged, number of open screw holes, operative time, rod removal, complications and time to radiographic healing. To be included, dogs had to have evidence of radiographic healing during follow-up. Eight dogs with diaphyseal radius and ulna fractures treated with MIPR were included in the case series. All fractures were due to trauma and two fractures were open (grade 1). Rod loosening and osteomyelitis of the ulna occurred in one case which subsequently resolved with rod removal. Healing occurred in all cases with no implant failures. Median time to radiographic union was 10.5 weeks (mean ± SD = 17 ± 15 weeks; range 4-52 weeks). Use of MIPR constructs on diaphyseal fractures of the radius and ulna is an effective technique for managing these fractures using principles of biological osteosynthesis. An intramedullary rod in the ulna assists with fracture reduction and stabilisation and rod removal is recommended once fracture healing has occurred.
    Veterinary and Comparative Orthopaedics and Traumatology 01/2010; 23(6):459-67. · 1.03 Impact Factor
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    ABSTRACT: The objectives of this study were to describe a new spinal cord injury scale for dogs, evaluate repeatability through determining inter-rater variability of scores, compare these scores to another established system (a modified Frankel scale), and determine if the modified Frankel scale and the newly developed scale were useful as prognostic indicators for return to ambulation. A group of client-owned dogs with spinal cord injury were examined by 2 independent observers who applied the new Texas Spinal Cord Injury Score (TSCIS) and a modified Frankel scale that has been used previously. The newly developed scale was designed to describe gait, postural reactions and nociception in each limb. Weighted kappa statistics were utilized to determine inter-rater variability for the modified Frankel scale and individual components of the TSCIS. Comparisons were made between raters for the overall TSCIS score and between scales using Spearman's rho. An additional group of dogs with surgically treated thoracolumbar disk herniation was enrolled to look at correlation of both scores with spinal cord signal characteristics on magnetic resonance imaging (MRI) and ambulatory outcome at discharge. The actual agreement between raters for the modified Frankel scale was 88%, with a weighted kappa value of 0.93. The TSCIS had weighted kappa scores for gait, proprioceptive positioning and nociception components that ranged from 0.72 to 0.94. Correlation between raters for the overall TSCIS score was Spearman's rho=0.99 (P<0.001). Comparison of the overall TSCIS score to the modified Frankel score resulted in a Spearman's rho value of 0.90 (P<0.001). The modified Frankel score was weakly correlated with the length of hyperintensity of the spinal cord: L2 vertebral body length ratio on mid-sagittal T2-weighted MRI (Spearman's rho=-0.45, P=0.042) as was the overall TSCIS score (Spearman's rho=-0.47, P=0.037). There was also a significant difference in admitting modified Frankel scores (P=0.029) and admitting overall TSCIS scores (P=0.02) between dogs that were ambulatory at discharge and those that were not. Results from this study suggest that the TSCIS is an easy to administer scale for evaluating canine spinal cord injury based on the standard neurological exam and correlates well with a previously described modified Frankel scale.
    Preventive Veterinary Medicine 05/2009; 89(1-2):121-7. · 2.39 Impact Factor
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    ABSTRACT: To document cartilage damage associated with elbow lameness in dogs without radiographic signs. Case series. Dogs (n=16). Medical records (November 2004-January 2006) of dogs with undiagnosed forelimb lameness localized to the elbow but without radiographic signs that had lesions identified by either computed tomography (CT) or nuclear scintigraphy and confirmed by arthroscopy were included. Signalment, duration of clinical signs before admission, surgical diagnosis, and treatment were recorded. Sixteen dogs (10 left, 6 right elbows) were identified. Median age was 30.1 months and median duration of clinical signs before admission was 15.6 months. CT or scintigraphy were strongly suggestive of elbow pathology before confirmation by arthroscopy. Medial coronoid pathology was identified in every abnormal elbow and osteochondrosis dissecans in 2 elbows. Elbow pathology not associated with radiographic changes can be identified by CT and scintigraphy. Coronoid pathology is the most likely diagnosis. Absence of radiographic signs in elbows with clinical signs of lameness should be evaluated with advanced imaging techniques (CT, scintigraphy) and arthroscopy to identify the cause of lameness.
    Veterinary Surgery 03/2009; 38(2):209-12. · 1.24 Impact Factor