Evaluation of postsale endoscopy as a predictor of future racing performance in an Australian thoroughbred yearling population.

INTRODUCTION: Upper airway endoscopy of thoroughbred (TB) yearlings is commonly used in an attempt to predict laryngeal function (LF) and its impact on future race performance. The aim of this study was to determine if different grading systems and laryngeal grades were correlated with future performance. MATERIALS AND METHODS: Postsale endoscopic recordings were obtained from an Australian TB yearling sale during a four-year period from 2008 to 2011. Horses were included if they had a diagnostic postsale video endoscopic recording and raced within Australia. Recordings were graded using the Havemeyer system and subsequently recategorised according to the Lane scale and two condensed scales. Performance data were sourced from Racing Australia and comparisons were made between groups. RESULTS: A total of 1244 horses met the inclusion criteria. There were no significant differences in sex or sales price between groups. There were no significant differences in the number of starts or wins between groups for any grading system. For the condensed Havemeyer scale, horses with intermediate LF were separated into two groups. Significant differences in earnings were found between 'normal' and 'abnormal' (P = 0.02) and 'intermediate-low' and 'abnormal' grades (P = 0.03). There were no significant differences between horses with 'intermediate-high' and 'abnormal' grades (P = 0.40). No significant differences were found between the two intermediate grades (P = 0.60) or between horses with normal LF and either 'intermediate-low' or 'intermediate-high' grades (P = 0.99). DISCUSSION: Resting LF in Australian yearling TBs assessed using a condensed Havemeyer grading scale had some predictive value for future racing performance. This information should be considered when performing yearling endoscopic examinations.

Physicians declining patient enrollment in a critical care trial: a case study in thromboprophylaxis.

PURPOSE: To analyze the frequency, rationale and determinants of attending physicians requesting that their eligible patients not be approached for participation in a thromboprophylaxis trial. METHODS: Research personnel in 67 centers prospectively documented eligible non-randomized patients due to physicians declining to allow their patients to be approached. RESULTS: In 67 centers, 3,764 patients were enrolled, but 1,460 eligible patients had no consent encounter. For 218 (14.9 %) of these, attending physicians requested that their patients not be approached. The most common reasons included a high risk of bleeding (31.2 %) related to fear of heparin bioaccumulation in renal failure, the presence of an epidural catheter, peri-operative status or other factors; specific preferences for thromboprophylaxis (12.4 %); morbid obesity (9.6 %); uncertain prognosis (6.4 %); general discomfort with research (3.7 %) and unclear reasons (17.0 %). Physicians were more likely to decline when approached by less experienced research personnel; considering those with[10 years of experience as the reference category, the odds ratios (OR) for physician refusals to personnel without trial experience was 10.47 [95 % confidence interval (CI) 2.19-50.02] and those with less than 10 years experience was 1.72 (95 % CI 0.61-4.84). Physicians in open rather than closed units were more likely to decline (OR 4.26; 95 % CI 1.27-14.34). Refusals decreased each year of enrollment compared to the pilot phase. CONCLUSIONS: Tracking, analyzing, interpreting and reporting the rates and reasons for physicians declining to allow their patients to be approached for enrollment provides insights into clinicians' concerns and attitudes to trials. This information can encourage physician communication and education, and potentially enhance efficient recruitment.

Case-control study of high-speed exercise history of Thoroughbred and Quarter Horse racehorses that died related to a complete scapular fracture.

REASONS FOR PERFORMING STUDY: Identification of exercise history patterns that are related to catastrophic scapular fracture will facilitate prevention of racehorse fatalities. OBJECTIVES: To determine if exercise patterns are associated with scapular fracture in Thoroughbred (TB) and Quarter Horse (QH) racehorses. METHODS: High-speed exercise histories for 65 TB and 26 QH racehorses that had a complete scapular fracture (cases) and 2 matched control racehorses were retrospectively studied. Exercise variables were created from lifetime race and official timed workout reports. Associations between exercise variables and scapular fracture were investigated using conditional logistic regression. RESULTS: Thoroughbreds with a scapular fracture had a greater number of workouts, events (combined works and races), and mean event distances than QHs with a scapular fracture. Quarter Horses worked less frequently and accumulated distance at a lower rate than TBs. Breed differences were not found for career race number or length, time between races or lay-up variables for horses with ≥1 lay-up. For both breeds, cases had fewer events, lower recent accumulated distance and fewer active days in training than controls; however, a subset of TB cases with >10 events since lay-up had a longer active career than controls. For QHs that had a lay-up, total and mean lay-up times were greater for cases than controls. Multivariable models revealed that odds ratios (OR) of scapular fracture were greater for TBs that had not yet raced (OR = 23.19; 95% confidence interval (CI) 3.03-177.38) and lower for QHs with more events (OR = 0.71; 95% CI 0.54-0.94). CONCLUSIONS AND CLINICAL RELEVANCE: Racehorses that are in early high-speed training but behind that of their training cohort should be examined for signs of scapular stress remodelling. Quarter Horses that had a prolonged lay-up and TBs that have endured high-speed training for a longer duration than that of their training cohort also were at greater risk.

Idiopathic haemarthrosis in eight horses.

OBJECTIVES: To review eight horses diagnosed with idiopathic haemarthrosis and to describe the intra-articular use of yttrium-90 ((90) Y) and methylprednisolone acetate (MPA) in recurrent haemarthrosis cases. DESIGN: Retrospective case series. METHOD: The medical records, diagnostic images, histopathology and outcome of all horses diagnosed with idiopathic haemarthrosis between 1998 and 2010 were reviewed. RESULTS: Four Thoroughbred racehorses with haemarthrosis of the antebrachiocarpal joint had severe acute lameness (median, grade 4) and marked joint effusion after high-speed exercise. Another four horses (2 Thoroughbred racehorses, 1 Standardbred racehorse, 1 Warmblood) had haemarthrosis of the tarsocrural joint and presented with mild, intermittent lameness (median, grade 1) and marked, persistent joint effusion. Six of the eight horses had recurrent haemarthrosis prior to treatment. Radiographic and nuclear scintigraphic examinations did not identify bone pathology. Diagnostic arthroscopy (7 cases) identified grossly hypertrophied yellow/brown discoloured synovium. Synovial histopathology of these cases revealed chronic synovial hyperplasia with severe haemosiderosis and granulomatous inflammatory reaction of varying severity. All horses underwent rest, bandaging and phenylbutazone administration. Two horses had subtotal mechanical synovectomy, four horses had intra-articular administration of (90) Y and MPA, and one horse underwent both treatments. Seven cases returned to their previous use (median time, 7 months). Haemarthrosis recurred in three horses, two of which had received the (90) Y and MPA treatment. CONCLUSION: Idiopathic haemarthrosis should be considered a differential for acute and recurrent joint related lameness and effusion. Recurrence appears not uncommon and the use of intra-articular (90) Y and MPA in conjunction with a conservative management treatment protocol warrants further evaluation.

Comparisons of computed tomography, contrast enhanced computed tomography and standing low-field magnetic resonance imaging in horses with lameness localised to the foot. Part 1: anatomic visualisation scores.

REASONS FOR PERFORMING STUDY: To date, few reports exist comparing magnetic resonance imaging (MRI) and computed tomography (CT) for imaging of the equine distal limb, yet clinicians are required to decide which modality to use regularly. OBJECTIVES: To report and compare anatomic visualisation scores obtained for CT, contrast enhanced CT (CECT) and standing low-field MRI (LFMRI) in the equine foot. HYPOTHESIS: Anatomic visualisation score discrepancies would exist between CT, CECT and LFMRI. METHODS: Images of 22 lame horses (31 limbs) undergoing both CT and LFMRI of the foot were reviewed. When available, CECT images were reviewed. The deep digital flexor tendon (DDFT) was categorised into proximal to distal levels (A-D), structures were assigned visualisation scores (Grades 0-3) and technique comparisons were made using the paired marginal homogeneity test. RESULTS: Computed tomography and LFMRI had similar visibility scores for the navicular bone, middle phalanx, DDFT-B, collateral ligaments of the distal interphalangeal joint and collateral sesamoidean ligament of the navicular bone. The proximal and distal phalanx had lower visibility scores with LFMRI. The distal DDFT (C-D), distal sesamoidean impar ligament and synovial structures had higher scores with LFMRI. Contrast enhanced CT lowered DDFT and collateral sesamoidean ligament scores and raised distal interphalangeal synovium CT visualisation scores. CONCLUSIONS AND POTENTIAL RELEVANCE: Visualisation scores differ depending on imaging technique and anatomic structure of interest. This information increases our understanding of the limitations of CT, CECT and LFMRI to visualise anatomy in clinical cases.

Characteristics of Thoroughbred and Quarter Horse racehorses that sustained a complete scapular fracture.

REASONS FOR PERFORMING STUDY: To determine if scapular fractures occur in racehorses with distinctive characteristics. OBJECTIVES: To test the hypothesis that Thoroughbred (TB) and Quarter Horse (QH) racehorses with a scapular fracture have similar characteristics that are different from those of their respective racetrack populations. METHODS: Necropsy findings, case details, last race information and career earnings for TB and QH racehorses that had a scapular fracture in California between 1990 and 2008 were retrospectively compared between breeds. Horse signalment, career earnings, career starts and race characteristics were obtained for all California racehorses. Comparisons were made between affected horses, other racehorses that died, and all horses that raced, in California during the 19 year period. RESULTS: Seventy-three TB and 28 QH racehorses had a similar, complete comminuted scapular fracture with an articular component, and right forelimb predilection. The QHs had a higher incidence of scapular fracture incurred during racing than TBs (0.98 vs. 0.39/1000 starters). The TB and QH incident rates for musculoskeletal deaths incurred racing were 20.5 and 17.5/1000 starters, respectively; however, a greater proportion of TB musculoskeletal deaths occurred training (40% vs. 8%). Horses with a scapular fracture were more likely to be male and aged 2 or ≥ 5 years than the racetrack population. Most affected QHs (64%) were 2-year-olds; most TBs (74%) were aged ≥ 3 years. Scapular fractures occurred more commonly during racing in QHs (70%) than TBs (44%). Race-related scapular fracture was more likely to occur in a Maiden race than in a non-Maiden race. Horses with a scapular fracture had fewer career starts than the racetrack population. CONCLUSIONS AND POTENTIAL RELEVANCE: Despite breed differences for signalment and exercise distances, both breeds incur a complete scapular fracture that is more likely to occur in the right scapula of young and older, male racehorses, early in their race career or after few races. Quarter Horses sustain a catastrophic scapular fracture more frequently than TBs.

Comparisons of computed tomography, contrast-enhanced computed tomography and standing low-field magnetic resonance imaging in horses with lameness localised to the foot. Part 2: Lesion identification.

REASONS FOR PERFORMING STUDY: No previous study compares computed tomography (CT), contrast-enhanced computed tomography (CECT) and standing low-field magnetic resonance imaging (LFMRI) to detect lesions in horses with lameness localised to the foot. This study will help clinicians understand the limitations of these techniques. OBJECTIVES: To determine if CT, CECT and LFMRI would identify lesions within the distal limb and document discrepancies with lesion distribution and lesion classification. METHODS: Lesions in specific structures identified on CT and MR images of feet (31 limbs) from the same horse were reviewed and compared. Distributions of lesions were compared using a Chi-squared test and techniques analysed using the paired marginal homogeneity test for concordance. RESULTS: Lesions of the deep digital flexor tendon (DDFT) were most common and CT/CECT identified more lesions than LFMRI. Deep digital flexor tendon lesions seen on LFMRI only were frequently distal to the proximal extent of the distal sesamoid and DDFT lesions seen on CT/CECT only were frequently proximal to the distal sesamoid. Lesions identified on LFMRI only were core (23.3%) or splits (43.3%), whereas lesions identified only on CT were abrasions (29.8%), core (15.8%), enlargement (15.8%) or mineralisation (12.3%). Contrast-enhanced CT improved lesion identification at the DDFT insertion compared to CT and resulted in distal sesamoidean impar ligament and collateral sesamoidean ligament vascular enhancement in 75% of cases. Low-field MRI and CT/CECT failed to identify soft tissue mineralisation and bone oedema, respectively. CONCLUSIONS AND POTENTIAL RELEVANCE: Multiple lesions are detected with CT, CECT and LFMRI but there is variability in lesion detection and classification. LFMRI centred only on the podotrochlear apparatus may fail to identify lesions of the pastern or soft tissue mineralisation. Computed tomography may fail to identify DDFT lesions distal to the proximal border of the distal sesamoid.

Possible role of carpal hyperextension in superficial digital flexor tendinopathy.

REASONS FOR PERFORMING STUDY: The specific biomechanical circumstances that induce excessive superficial digital flexor tendon (SDFT) strain in horses are unknown. HYPOTHESIS: Carpal joint hyperextension during axial limb loading during the middle of stance disproportionately enhances SDFT strains compared to suspensory ligament (SL) strains. METHODS: Superficial digital flexor tendon and SL strains were measured in 7 cadaver limbs during in vitro loading that maintained carpal extension or allowed carpal hyperextension by constraining, or allowing rotation of, the radius during loading conditions that simulated the middle of stance at the walk. The effect of carpal hyperextension on SDFT and SL strains and joint angles was assessed using repeated measures ANOVA. RESULTS: Limb loading generally resulted in higher SL strains than SDFT strains for both carpal extension and hyperextension loading conditions. Compared to carpal extension, carpal hyperextension resulted in increased strains in both the SDFT and the SL; however, a greater increase in strain was seen in the SDFT. On average, carpal hyperextension caused approximately 3° greater carpal extension, 1° greater metacarpophalangeal joint hyperextension, 1° greater proximal interphalangeal joint flexion and <1° greater distal interphalangeal joint flexion than did carpal extension. CONCLUSIONS AND CLINICAL RELEVANCE: Carpal joint hyperextension is likely to induce disproportionately higher strain in the SDFT than in the SL. Factors that affect carpal stability are likely to affect the risk for superficial digital flexor tendinopathy.

Catastrophic scapular fractures in Californian racehorses: pathology, morphometry and bone density.

REASONS FOR PERFORMING STUDY: To enhance understanding of the nature and pathogenesis of scapular fractures in racehorses. HYPOTHESIS: Scapular fractures in racehorses have a consistent configuration related to sites of pre-existing stress modelling and remodelling. METHODS: Fractured and intact scapulae collected post mortem were examined visually and with computed tomography (CT). Scapular fracture configuration, bone modelling changes and standardised CT morphometry and density measurements were recorded. Statistical comparisons were made between fractured, nonfractured contralateral and control scapulae. RESULTS: Thirty-nine scapulae from 10 Thoroughbred (TB) and 10 Quarter Horse (QH) racehorses were obtained. All 14 fractured scapulae (from 12 horses) had a consistent comminuted fracture configuration. A complete fracture coursed transversely through the neck of the scapula at the level of the distal aspect of the spine (8.9 ± 0.9 cm proximal to the lateral articular margin of the glenoid cavity). The distal fragment of 13 fractured scapulae was split into 2 major fragments by a fracture in the frontal plane that entered the glenoid cavity (2.8 ± 0.4 cm caudal to the cranial articular margin). Focal areas of periosteal proliferation and/or radiolucency were present in the distal aspect of the scapular spine of all fractured and intact contralateral scapulae, but less commonly (P<0.01) in intact scapula from horses without a scapular fracture. Fractured scapulae had 7-10% lower mean density and 46-104% greater density heterogeneity in the spine adjacent to the transverse fracture compared to control scapulae (P<0.03). CONCLUSIONS AND CLINICAL RELEVANCE: Thoroughbred and QH racehorses have a characteristic scapular fracture configuration that is associated with pre-existing pathology of the distal aspect of the spine. This location is consistent with scapular stress fractures diagnosed in lame TB racehorses. Catastrophic fracture is the acute manifestation of a more chronic process. Consequently, there are opportunities for early detection and prevention of fatalities.

Focal cerebral oxygenation and neurological outcome with or without brain tissue oxygen-guided therapy in patients with traumatic brain injury.

BACKGROUND: In patients with severe traumatic brain injury (TBI), the depth and duration of cerebral hypoxia are independent predictors of outcome. This study aimed to evaluate the efficacy of brain oxygen-guided therapy in improving cerebral oxygenation and neurological outcome in severe TBI patients. METHODS: Thirty TBI patients had brain oxygen monitors placed contralateral to the side of mass lesions, or to the non-dominant side if injury was diffuse. The first 10 patients (Group 1, observational) had brain tissue oxygen (PbrO2) monitored, but not treated. The next 20 patients (Group 2, interventional) were treated according to brain tissue oxygen-guided algorithms aiming to improve cerebral oxygen availability. The 6-month neurological outcome of Group 2 patients was compared with that of Group 1 patients and with contemporary control patients (Group 3) treated without the use of brain oxygen monitoring. FINDINGS: The mean duration of brain hypoxic episodes (PbrO2 <15 mmHg) was 106 minutes in Group 1, and 34 minutes in Group 2 (p=0.01). Brain tissue oxygen was <15 mmHg for 10% of monitoring time in Group 1 and 2.8% in Group 2 (p=0.12). The peak incidence of cerebral hypoxic events in both groups occurred during post-injury day 5. The mean Injury Severity Score (ISS) of patients experiencing cerebral hypoxia was higher than that of patients without cerebral hypoxic episodes (33.7 vs 24.2, p=0.04). There was no statistically significant difference in neurological outcome between those patients treated with and those without brain oxygen-guided therapy. CONCLUSIONS: In TBI patients, brain tissue oxygen-guided therapy is associated with decreased duration of episodes of cerebral hypoxia. Larger studies are indicated to determine the effects of this therapy on neurological outcome.

When it's not appendicitis.

Other pathology besides appendicitis may be found in patients with right lower quadrant pain. This has led some to advocate diagnostic laparoscopy/laparoscopic appendectomy for all such cases. This policy would substantially raise the costs of care without a priori proof of its efficacy. However, a selective approach on when to proceed with diagnostic laparoscopy will depend on the frequency of finding unexpected, nonappendiceal pathology. To determine this, we reviewed our experience with 202 appendectomies. For females < 50 years old, 33 per cent had normal appendices, 12 per cent had periappendicitis, 47 per cent had acute appendicitis, 12 per cent had perforated appendicitis, and 26 per cent had other nonappendiceal pathology. For males < 50 years old, 13 per cent had normal appendices, 8 per cent had periappendicitis, 67 per cent had acute appendicitis, 15 per cent had perforated appendicitis, and 5 per cent had other pathology. For patients > 50 years old, 7 per cent had normal appendices, 13 per cent had periappendicitis, 33 per cent had acute appendicitis, 60 per cent had perforated appendicitis, and 20 per cent other pathology. Other nonappendiceal pathology was found in 42 per cent of females < 50 with normal appendices, 57 per cent with periappendicitis, and 14 per cent with acute/perforated appendicitis. In males < 50 years, 50 per cent of those with normal appendices, 10 per cent of those with periappendicitis, and 0.7 per cent of those with acute appendicitis had nonappendiceal pathology. In conclusion, women of childbearing age and patients > 50 years old have a significant incidence of nonappendiceal pathology. In this group of patients, a diagnostic laparoscopy appears justifiable to identify the cause of the abdominal pain.

Quality of life scale for gastroesophageal reflux disease.

BACKGROUND: Treatment of uncomplicated gastroesophageal reflux disease (GERD) is primarily to improve the symptoms of the patient. However, measurement of symptomatic outcome is difficult because it is as the patient perceives it to be and not "objective." This creates a need to develop a simple and understandable instrument to measure symptomatic outcome. STUDY DESIGN: All patients referred for evaluation of GERD were eligible for this prospective study. During the initial visit, patients were asked to complete the Gastroesophageal Reflux Data Sheet. This ten-item questionnaire included an overall assessment of satisfaction; the best possible score was 0, and the worst was 45. The evaluation included history, physical examination, and additional studies, including upper gastrointestinal series, esophagogastroduodenoscopy, esophageal manometry, and 24-hour esophageal pH monitoring as indicated. Initial treatment was medical with histamine2-blockers, omeprazole, cisapride, or both. If a patient was dissatisfied with medical treatment and had both a hypotensive lower esophageal sphincter and abnormal results of the 24-hour pH monitoring, then operative treatment with either laparoscopic or open Nissen or Toupet fundoplication was offered. After approximately three months of medical treatment or one month after operative treatment, patients were asked to complete the questionnaire again. Data were analyzed using nonparametric tests and linear regression analysis. RESULTS: A total of 72 patients were assessed, and 100 percent of them completed the questionnaire. Patients who were satisfied with their condition had a median health-related quality of life (HRQL) score of five, and those who were dissatisfied had a median score of 26 (p < 0.000001). Patients who ultimately chose surgical therapy had a median preoperative score of 28, compared with 15 for patients who chose to continue medical therapy (p = 0.0001). The change in HRQL score from before treatment to after treatment for surgical patients was 27 compared with 11 for medically treated patients (p < 0.002). Items 1 through 6 of the questionnaire were individually sensitive to the effects of treatment. However, there was no correlation between HRQL and the composite pH score or with the lower esophageal sphincter pressure. CONCLUSIONS: This HRQL score has advantages over standard health status instruments for GERD including simplicity for patients (and therefore a high compliance rate), ease of understanding for physicians, and sensitivity to the effects of treatment. In addition, it may help determine, early in the course of treatment, patients who may ultimately require surgical therapy, thereby avoiding prolonged, but futile, medical therapy.

Application of Doppler/ultrasound examination for varicose veins in a provincial hospital.

There are a number of different primary problems in patients presenting with varicose veins. Treatment needs to be appropriate to the different causes. Doppler/ultrasound examination of varicose veins can very accurately define almost all abnormalities that cause varicose veins, but this can be time consuming. Over 3 years' experience of the clinical application of colour Doppler/ultrasound investigation in the assessment of patients with varicose veins in a small general hospital is reported. The selection of patients and how improved understanding of the various presenting problems of patients examined may affect treatment are described. All surgeons with access to this technology are encouraged to include it in the investigation of their patients.

Monoclonal antibodies to mammalian D-type G1 cyclins.

D-type cyclins are necessary and rate-limiting for G1 progression during the mammalian cell cycle. Cyclins D1, D2, and D3 are encoded by distinct genes and are expressed in proliferating cells in a lineage-specific manner. Monoclonal antibodies (mAbs) generated to bacterially produced recombinant D-type cyclins were able to react with the native proteins expressed in mammalian cells. One mouse and three rat mAbs immunoprecipitated cyclin D1 from mouse macrophages. Only rat mAbs reacted with human cyclin D1 and cross-reacted with cyclin D2 expressed in proliferating T lymphocytes and human tumor cell lines. A single rat mAb to cyclin D2 exhibited a pattern of reactivity reciprocal to that of rat mAbs to D1. Three rat mAbs reacted specifically with mouse or human cyclin D3, but did not cross-react with cyclins D1 or D2 from either species. Representative mAbs were useful for immunoblotting and detected D-type cyclins coprecipitating in complexes recovered with antiserum to cyclin-dependent kinase-4 (CDK4). Because these mAbs detect D-type cyclins in the nuclei of fixed permeabilized cells, they should prove useful in documenting cyclin overexpression in those human tumors in which the genes are amplified or are targets of specific chromosomal rearrangements.

Retrograde venography and colour Doppler imaging of a popliteal venous aneurysm.

Popliteal venous aneurysms are rare and usually manifest with formation of thrombus and embolization to the lungs. The radiological features of a popliteal venous aneurysm, without thrombus, initially identified by ultrasound with colour Doppler imaging and further investigated with retrograde venography is described.