bluuebunny/crossref_metadata_2025_split huggingface dataset:
AnIn VitroBiomechanical Comparison of an Interlocking Nail System and Dynamic Compression Plate Fixation of Ostectomized Equine Third Metacarpal Bones
Authors: Lopez Mandi J. , Wilson David G. , Vanderby Ray , Markel Mark D. 
Published: April 2004

ObjectiveTo compare the mechanical properties of two stabilization methods for ostectomized equine third metacarpi (MC3): (1) an interlocking nail system and (2) two dynamic compression plates.Animal or Sample PopulationTen pairs of adult equine forelimbs intact from the midradius distally.MethodsTen pairs of equine MC3 were divided into two test groups (five pairs each): caudocranial four‐point bending and torsion. Interlocking nails (6 hole, 13‐mm diameter, 230‐mm length) were placed in one randomly selected bone from each pair. Two dynamic compression plates one dorsally (12 hole, 4.5‐mm broad) and one laterally (10 hole, 4.5‐mm broad) were attached to the contralateral bone from each pair. All bones had 1 cm mid‐diaphyseal ostectomies.Five construct pairs were tested in caudocranial four‐point bending to determine stiffness and failure properties. The remaining five construct pairs were tested in torsion to determine torsional stiffness and yield load. Mean values for each fixation method were compared using a pairedt‐test within each group. Significance was set atP< .05.ResultsMean (±SEM) values for the MC3‐interlocking nail composite and the MC3‐double plate composite, respectively, in four‐point bending were: composite rigidity, 3,454 ± 407.6 Nm/rad and 3,831 ± 436.5 Nm/rad; yield bending moment, 276.4 ± 40.17 Nm and 433.75 ± 83.99 Nm; failure bending moment, 526.3 ± 105.9 Nm and 636.2 ± 27.77 Nm. There was no significant difference in the biomechanical values for bending between the two fixation methods. In torsion, mean (±SEM) values for the MC3‐interlocking nail composite and the MC3‐double plate composite were: composite rigidity, 124.1 ± 16.61 Nm/rad and 262.4 ± 30.51 Nm/rad; gap stiffness, 222.3 ± 47.32 Nm/rad and 1,557 ± 320.9 Nm/rad; yield load, 94.77 ± 7.822 Nm and 130.66 ± 20.27 Nm, respectively. Composite rigidity, gap stiffness, and yield load for double plate fixation were significantly higher compared with interlocking nail fixation in torsion.ConclusionsNo significant differences in biomechanical properties were identified between an interlocking nail and double plating techniques for stablilization of ostectomized equine MC3 in caudocranial four‐point bending. Double plating fixation was superior to interlocking nail fixation in torsion.Clinical RelevanceDouble plate fixation is biomechanically superior to interlocking nail fixation in vitro in ostectomized equine MC3 bones.
AnIn VitroBiomechanical Comparison of Two Fixation Methods for Transverse Osteotomies of the Medial Proximal Forelimb Sesamoid Bones in Horses
Authors: Wilson David A. , Keegan Kevin G. , Carson William L. 
Published: April 2004

ObjectiveThis study compared the mechanical properties of the normal intact suspensory apparatus and two methods of fixation for repair of transverse, midbody fractures of the proximal sesamoid bones of adult horses: transfixation wiring (TW) and screws placed in lag fashion (LS).Study DesignAnin vitro,paired study using equine cadaver limbs mounted in a loading apparatus was used to test the mechanical properties of TW and LS.Animal or Sample PopulationSeventeen paired (13 repaired, 4 normal) equine cadaver limbs consisting of the suspensory apparatus third metacarpal bone, and first and second phalanges.MethodsThe two methods of repair and normal intact specimens were evaluated in single cycle‐to‐failure loading. Yield failure was defined to occur at the first notable discontinuity (>50 N) in the load‐displacement curve, the first visible failure as evident on the videotape, or a change in the slope of the moment‐fetlock angle curve. Ultimate failure was defined to occur at the highest load resisted by the specimen. Corresponding resultant force and force per kg of body weight on the suspensory apparatus, fetlock joint moment, and angle of fetlock dorsiflexion were calculated by use of specimen dimensions and applied load. These were compared along with specimen stiffness, and ram displacement.ResultsLoad on the suspensory apparatus, load on the suspensory apparatus per kg of body weight, moment, applied load, and angle of fetlock dorsiflexion at yield failure were significantly greater for the TW‐repaired than for the LS‐repaired specimens. A 3 to 5 mm gap was observed before yield failure in most TW‐repaired osteotomies.ConclusionsTransfixation wiring provided greater strength to yield failure than screws placed in lag fashion in single cycle load‐to‐failure mechanical testing of repaired transverse osteotomized specimens of the medial proximal forelimb sesamoid bone.Clinical RelevanceOur study indicates the initial strength of repair is greater following transfixation wiring than for lag screw fixation. Knowledge of the mechanical properties of these methods of fixation should aid the surgeon contemplating repair of mid‐body fractures of the proximal sesamoid bones.
Tenoscopic Examination and Proximal Annular Ligament Desmotomy for Treatment of Equine “Complex” Digital Sheath Tenosynovitis
Authors: Fortier Lisa A. , Nixon Alan J. , Ducharme Norm G. , Mohammed Hussni O. , Yeager Amy 
Published: April 2004

ObjectiveTo determine the outcome of horses with “complex” digital tenosynovitis treated by tenoscopic proximal annular ligament desmotomy and resection of synovial masses or adhesions, or both, within the digital sheath.Study DesignRetrospective evaluation.Animals or Sample PopulationTwenty‐five horses with a clinical and ultrasonographic diagnosis of palmar or plantar proximal annular ligament constriction and ultrasonographic evidence of synovial masses or adhesions within the digital tendon sheath.MethodsEach horse had tenoscopic surgery for annular ligament desmotomy combined with adhesiolysis and/or synovial mass resection. Mean follow‐up time was 3.4 years. Spearman's rank correlation was used to assess the relationship between functional outcome or cosmetic results and preoperative variables including duration of clinical signs, digital sheath synovial fluid total protein concentration and nucleated cell count, thickness of the palmar or plantar proximal annular ligament (PAL), severity of adhesions, severity of synovial masses, degree of synovial distention, or limb affected.ResultsA total of 18 (72%) horses returned to athletic soundness, 4 were improved but not sound, and 3 were not improved. Cosmetic outcome was normal in 10 horses, improved but not normal in 12, and not improved in 3 horses. Cosmetic and functional outcome were significantly adversely affected by the duration of clinical signs and the severity of synovial masses.ConclusionsWith appropriate tenoscopic surgical attention, horses with complex tenosynovitis syndrome characterized by synovial masses, adhesions, or both adhesions and masses, and PAL constriction, have a good prognosis for return to athletic soundness.Clinical RelevanceHorses with PAL constriction and additional digital tendon sheath pathology such as adhesions and synovial masses have a 72% chance of returning to sound athletic performance, however 60% of horses retain some degree of cosmetic blemish in the affected limb. There is an inverse relationship between the duration of clinical signs and outcome, and therefore, prompt surgical attention is advised.
Comparison of Incisional Bursting Strength of Simple Continuous and Inverted Cruciate Suture Patterns in the Equine Linea Alba
Authors: Magee Ashley A. , Galuppo Larry D. 
Published: April 2004

ObjectiveTo determine the bursting strength of ventral median abdominal incisions closed by either simple continuous or inverted cruciate suture patterns.Study DesignExperimental.Animal or Sample PopulationTwelve equine cadavers.MethodsA 25 cm ventral median incision was made through the linea alba and a 200 L polyurethane bladder was placed within the abdomen. Either a simple continuous or an inverted cruciate pattern using 3 polyglactin 910 with a bite size and suture interval of 1.5 cm was used to close linea incisions. Closure time was recorded for each pattern. The bladder was inflated with air at 40 L/min, and the pressure at body wall failure recorded. The length of suture used for wound closure and the wound failure modes were recorded. Deviation from the linea (cm), total suture length (cm), suture length to wound length ratio (SL:WL), closure time (min), bursting pressure (mm Hg), and failure modes were compared between groups using Welch‐Aspint‐tests. The effects of independent subject variables were assessed for possible effects on bursting strength using analysis of covariance.ResultsMean bursting pressure was significantly greater for the simple continuous pattern than for the inverted cruciate pattern (P= .01). Significantly less suture material (P= .0002) was required with the continuous pattern than with the inverted cruciate pattern. Mean closure time, SL:WL, deviation from the linea, and failure modes were not significantly different between groups. No significant effects were noted for independent variables in both groups on bursting strength.ConclusionsIn this model, a simple continuous closure pattern for ventral median abdominal incisions was stronger than an inverted cruciate pattern. A simple continuous pattern leaves less foreign material in the wound, which may be of benefit in reducing incisional complications.Clinical RelevanceUse of a continuous closure pattern for the linea alba may offer greater wound security during episodes of increased intra‐abdominal pressure in horses.
Growth Characteristics of Fibroblasts Isolated From the Trunk and Distal Aspect of the Limb of Horses and Ponies
Authors: Miller Christy Bacon , Wilson David A. , Keegan Kevin G. , Kreeger John M. , Adelstein Edward H. , Ganjam Venkataseshu K. 
Published: April 2004

Objective—To determine if there is a difference in in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. To determine the effects of a corticosteroid and monokine on in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies.Study Design—Growth of fibroblasts from tissues harvested from the trunk and limb were compared from horse and pony samples grown in control media and control media with triamcinolone or monokine added.Animals or Sample Population—Dermal and subcutaneous tissue from 22 horses and 17 ponies of various ages and breeds.Methods—Fibroblast growth was assessed by tritiated thymidine uptake using standard cell culture techniques. The effect of a monokine or triamcinolone plus control media were compared with control media for fibroblast growth.Results—Fibroblast growth from tissues isolated from the horse limb was significantly less than growth from the horse trunk and the limb and trunk of ponies. Monokine was more effective than triamcinolone in suppressing fibroblast growth from tissues isolated from the trunk and limb in both horses and ponies.Conclusions—There are growth differences in fibroblasts isolated from the limb of horses compared with those isolated from the trunk and from the limb and trunk of ponies.Clinical Relevance—The difference in fibroblast growth from tissues isolated from the trunk and limb of horses and ponies may provide evidence for the difference reported in the healing characteristics of limb wounds in horses and ponies. Influencing fibroblast growth may provide a key to controlling the development of exuberant granulation tissue in horses and ponies.
Surgical Treatment of Lumbosacral Instability Caused by Discospondylitis in Four Dogs
Authors: Auger J. , Dupuis J. , Quesnel A. , Beauregard G. 
Published: April 2004

Objective— To describe a surgical technique involving distraction and stabilization of the lumbosacral vertebral segment using an external skeletal fixator in dogs with lumbosacral instability caused by discospondylitis.Study Design— Retrospective clinical study.Animals— Four client‐owned dogs.Methods— Medical records of all dogs diagnosed with discospondylitis from 1994 to 1997 were identified and reviewed. Four dogs with lumbosacral discospondylitis requiring surgical treatment were then specifically studied. Surgical technique, clinical signs, preoperative diagnostic investigation, radiographic findings, and the results of short‐term and long‐term reevaluations were recorded.Results— Twelve dogs with discospondylitis were identified, 4 of which had lumbosacral discospondylitis. These 4 dogs underwent surgical distraction and stabilization because they failed to respond to medical treatment. Three dogs received a cancellous bone graft between L7 and S1 and had rapid interbody fusion of this vertebral segment. The dog that did not receive a graft did not have interbody fusion at the time of fixator removal. This did not affect the final clinical outcome. Lumbosacral pain and neurological deficits present before surgery rapidly subsided after the procedure. All dogs received concurrent antibiotic treatment for a minimum of 4 weeks. All dogs were clinically normal at the time of fixator removal and all continued to do well during the follow‐up period (8–48 months; mean, 27.5 months).Conclusion and Clinical Relevance— Lumbosacral discospondylitis may not respond well to conservative treatment because of the mobility of the affected space. Surgical treatment involving distraction and stabilization to obtain intervertebral fusion is very effective in treating lumbosacral instability caused by discospondylitis.
Perioperative Stress Response in the Dog: Effect of Pre‐Emptive Administration of Medetomidine
Authors: Benson G. John , Grubb Tamara L. , Neff‐Davis Carol , Olson William A. , Thurmon John C. , Lindner Donna L. , Tranquilli William J. , Vanio Outi 
Published: April 2004

Objective—To determine the effect of medetomidine on the stress response induced by ovariohysterectomy in isoflurane‐anesthetized dogs.Study Design—Prospective randomized study.Animals—Twelve healthy adult female purpose‐bred dogs, weighing 16.8 to 25 kg.Methods—Two treatments were randomly administered to each of twelve dogs at weekly intervals: (1) Saline injected IM followed in 15 minutes by isoflurane anesthesia (ISO) induced by mask and maintained at an end‐tidal concentration of 1.8% for 60 minutes; and (2) Medetomidine, 15 μg/kg IM followed in 15 minutes by isoflurane anesthesia (ISO & MED) induced by mask and maintained at an end‐tidal concentration of 1.0% for 60 minutes. One week after completion of these two treatments, all dogs were ovariohysterectomized, six receiving each treatment (SURG and SURG&MED). Central venous blood samples (10 mL) were obtained immediately before medetomidine or saline (baseline) and at 30, 75, and 195 minutes and 24 hours after administration of medetomidine or saline in ISO and ISO&MED. In SURG and SURG&MED, samples were obtained immediately prior to injection of medetomidine or saline (baseline) and at 30 (before skin incision), 45 (after severence of the ovarian ligament), 75 (after skin closure), 105 (30 minutes after skin closure, dog recovered and in sternal recumbency), 135, 195, 375 minutes, and 24 hours after the initial sample. Samples were analyzed for epinephrine, norepinephrine, adrenocorticotrophic hormone (ACTH), cortisol, insulin, and glucose. Data were analyzed by analysis of variance and where significant differences were found, a least significant difference test was applied.Results—Premedication with medetomidine prevented or delayed the stress response induced by ovariohysterectomy in isoflurane‐anesthetized dogs.Conclusions—The stress response induced by ovariohysterectomy, although significant, is of short duration. Medetomidine safely and effectively reduced surgically‐induced stress responses.Clinical Relevance—Surgically induced stress responses can be obtunded or prevented by administration of medetomidine.
The Recovery of Horses From Inhalant Anesthesia: A Comparison of Halothane and Isoflurane
Authors: Donaldson L.L. , Dunlop G.S. , Holland M.S. , Burton B.A. 
Published: April 2004

Objective—Recovery is one of the more precarious phases of equine general anesthesia. The quality and rate of recovery of horses from halothane and isoflurane anesthesia were compared to determine differences in the characteristics of emergence from these commonly used inhalant anesthetics.Experimental Design—Prospective, randomized blinded clinical trial.Sample Population—A total of 96 Thoroughbred and 3 Standardbred racehorses admitted for elective distal forelimb arthroscopy.Methods—All horses were premedicated with intravenous xylazine, induced with guaifenesin and ketamine, and maintained on a large animal circle system fitted with an out of the circle, agent specific vaporizer. Recoveries were managed by a blinded scorer with a standardized protocol. A 10 category scoring system was used to assess each horse's overall attitude, purposeful activity, muscle coordination, strength and balance from the time of arrival in recovery to standing. Times to extubation, sternal recumbency and standing were recorded. Median recovery scores and mean times to extubation, sternal and standing were compared using the Mann‐Whitney U test and student's t test, respectively.Results—The median score for horses recovering from halothane was lower (20.0; range, 10 to 57) than that for horses recovering from isoflurane (27.5; range, 10 to 55). Horses in the two groups were extubated at similar mean times (halothane, 11.3 ± 5.5 and isoflurane, 9.5 ± 5.2 minutes) but horses recovering from isoflurane achieved sternal recumbency (halothane, 37.7 ± 12.1 and isoflurane, 24.7 ± 8.8 minutes) and stood (halothane, 40.6 ± 12.9 and isoflurane, 27.6 ± 9.6 minutes) sooner than those recovering from halothane.Conclusions—The recovery of horses from isoflurane anesthesia was more rapid but less composed than that from halothane.Clinical Relevance—The quality of recovery following isoflurane was worse than after halothane anesthesia using the criteria chosen for this study. However, the range of recovery scores was similar for both groups and all horses recovered without significant injury.
Determination of the Minimum Anesthetic Concentration and Cardiovascular Dose Response for Sevoflurane in Chickens During Controlled Ventilation
Authors: Naganobu Kiyokazu , Fujisawa Yutaka , Ohde Hirotaka , Matsuda Yoshiko , Sonoda Tatsunobu , Ogawa Hiroyuki 
Published: April 2004

Objective—To determine the minimum anesthetic concentration for sevoflurane and effects of various multiples of minimum anesthetic concentration on arterial pressure and heart rate during controlled ventilation in chickens.Study Design—Prospective experimental study.Animals—Seven healthy chickens, 6 to 8 months old, weighing 1.6 to 3.4 kg.Methods—A rebreathing, semiclosed anesthetic circuit was used. Anesthesia was induced by mask with sevoflurane in oxygen. Each chicken was endotracheally intubated, then controlled ventilation was started and the end‐tidal CO2partial pressure was maintained at 30 to 40 mm Hg. Body temperature was maintained at 39.5° to 41.0°C. The inspired and end‐tidal sevoflurane concentration were monitored with a multigas monitor. Minimum anesthetic concentration was determined as the minimal end‐tidal sevoflurane concentration which prevented gross purposeful movement in response to clamping a toe for 1 minute. After the determination, the cardiovascular effects of sevoflurane at 1.0, 1.5, and 2.0 times the minimum anesthetic concentration were determined.Results—The minimum anesthetic concentration for sevoflurane was 2.21%+ 0.32% (mean ± SD). Mean arterial pressure and heart rate at minimum anesthetic concentration were 84 ± 13 mm Hg and 150 ± 58 beats/min, respectively. There was a dose‐dependent decrease in arterial pressure. The heart rate did not change significantly over the range 1 to 2 × minimum anesthetic concentration. No cardiac arrhythmias developed throughout the experiments.Conclusions and Clinical Relevance—The minimum anesthetic concentration for sevoflurane in chickens was within the range of minimum alveolar concentration reported in mammals. When the concentration of sevoflurane is increased during controlled ventilation in chickens, decrease in arterial pressure should be expected.
Perioperative Management of Calves Undergoing Implantation of a Left Ventricular Assist Device
Authors: Wilson D.V. , Kantrowitz A. , Pacholewicz J. , Salat O. , Paules B.R. , Zhou Y. , Dawe E.J. 
Published: April 2004

Objective—To describe perioperative management of calves that underwent left lateral thoracotomy, aortic cross‐clamping, partial left heart bypass and implantation of a left ventricular assist device.Sample Population—A total of 43 healthy castrated male calves, weighing 121 ± 24 kg.Results—Diazepam (mean ± SD,0.26 ± 0.07 mg/kg), ketamine (5.9 ± 2.17 mg/kg) and isoflurane were used in the anesthetic management of calves undergoing implantation of a left ventricular assist device in the descending thoracic aorta. Other adjunctive agents administered were fentanyl (11 ± 5.4 μg/kg), lidocaine (4.9 ± 3.19 mg/kg), bupivacaine (0.75%) and butorphanol (0.49 ± 0.13 mg/kg). None of the calves regurgitated at induction or during intubation. A tube was used to drain the rumen and prevent bloat during the procedure.Partial left heart bypass was used to perfuse the caudal half of the body during the period of aortic cross clamp and device implantation. Initial mean systemic blood pressure was 96 ± 25 mm Hg, and pressures measured in the auricular artery increased during aortic cross‐clamping and bypass. Vasoconstrictor therapy was required to treat caudal arterial hypotension during the procedure in 9 calves. Mean systemic arterial pressures returned to baseline values by the end of the anesthetic period. Initial mean pulmonary arterial pressures(PAP) were 22 ± 3 mm Hg. A significant but transient increase in pulmonary arterial pressure occurred after both heparin and protamine administration.Conclusions—The described anesthetic protocol was effective for thoracotomy and implantation of an intra‐aortic left ventricular assist device in normal calves. Partial left ventricular bypass was a useful adjunct during the period of aortic cross clamp. The doses of heparin and protamine administered were effective. Responsibility to monitor oxygenation of the cranial half of the animal continues during the bypass period as hypoxemia due to pulmonary dysfunction will not be detected by the perfusionist.