Three-dimensional magnetic resonance cholangiography is superior to two-dimensional single-shot magnetic resonance cholangiography for visualization and image quality of the feline and canine biliary tract: A postmortem study

Magnetic resonance cholangiography (MRC) is an established diagnostic tool for noninvasive assessment of the biliary tract in humans. It has also been found to be feasible in companion animals, but no published studies have compared MRC sequences in veterinary medicine. The present study is part of a prospective, observational, analytical investigation on MR cholangiopancreatography performed on the donated bodies of 12 cats and eight dogs. The main aim of this study was to compare the images of 2D-SSh-TSE-MRC and 3D-TSE-MRC sequences for visualization and image quality of the feline and canine biliary tract. Both sequences are T2-weighted and noncontrast. Three independent readers scored the visibility of four segments of the biliary tract, namely the gallbladder (GB), cystic duct, common bile duct (CBD), and extrahepatic ducts, and the image quality of the two MRC sequences using five-point Likert scales. Wilcoxon signed-rank test was used to compare the scores between the MRC sequences separately for cats and dogs. Inter- and intraobserver agreements were measured using Gwet's AC2 with linear weighting. The 3D-TSE-MRC images were scored significantly higher than the 2D-SSh-TSE-MRC for both visibility and image quality (P < .001-.016 for cats, P = .008-.031 for dogs); the only exception was GB in dogs. In both cats and dogs, interobserver agreement for segment visibility and image quality ranged from slight to substantial in 2D-SSh-TSE-MRC and from poor to almost perfect in 3D-TSE-MRC. Most of the assessments (73% for segment visibility and 66% for image quality) had substantial to almost perfect intraobserver agreement. Findings from the current study support the use of 3D-TSE-MRC over 2D-SSh-TSE-MRC for evaluation of the feline and canine biliary tract, but further studies on live animals are warranted.

Feasibility of Magnetic Resonance Cholangiopancreatography in Dogs-A Post-Mortem Study

Magnetic resonance cholangiopancreatography (MRCP) is commonly used in humans and is also feasible in cats. The aim of this post-mortem study was to investigate the feasibility of MRCP in eight adult dogs by comparing the visibility and measured diameters of the biliary tract and pancreatic ducts in MRCP with those of fluoroscopic retrograde cholangiopancreatography (FRCP) and corrosion casting. In autopsy, six dogs had no evidence of hepatobiliary disorders, one had pancreatic pathology, and one had biliary pathology. The gallbladder (GB), cystic duct, and common bile duct (CBD) were visible in the MRCP images of all eight dogs. However, the extrahepatic ducts and pancreatic ducts were only variably visible. There was statistical agreement between MRCP and FRCP in measuring the diameters of the GB (fundus and body) and CBD (at papilla and extrahepatic ducts' junction). The diameter measurements correlated between MRCP and corrosion casting. Our study showed that MRCP is feasible in dogs and allowed for proper visualization of the biliary tract. However, ducts with diameters of <1 mm were difficult to visualize using a 1.5 Tesla MRI machine. Further studies are warranted to apply MRCP in the diagnostic imaging of live dogs.

Cholangiopancreatography in cats: a post-mortem comparison of MRI with fluoroscopy, corrosion casting and histopathology

In human medicine, magnetic resonance cholangiopancreatography (MRCP) is a valuable diagnostic tool for hepatobiliary and pancreatic diseases. In veterinary medicine, however, data evaluating the diagnostic value of MRCP are limited. The primary objectives of this prospective, observational, analytical investigation were to assess whether MRCP reliably visualizes the biliary tract and pancreatic ducts in cats without and with related disorders, and whether MRCP images and measurements of the ducts agree with those of fluoroscopic retrograde cholangiopancreatography (FRCP), corrosion casting and histopathology. A secondary objective was to provide MRCP reference diameters for bile ducts, GB, and pancreatic ducts. Donated bodies of 12 euthanized adult cats underwent MRCP, FRCP, and autopsy with corrosion casting of the biliary tract and pancreatic ducts using vinyl polysiloxane. Diameters of the biliary ducts, gallbladder (GB), and pancreatic ducts were measured using MRCP, FRCP, corrosion casts and histopathologic slides. There was an agreement between MRCP and FRCP in measuring diameters of the GB body, GB neck, cystic duct, and common bile duct (CBD) at papilla. Strong positive correlations existed between MRCP and corrosion casting for measuring GB body and neck, cystic duct, and CBD at the extrahepatic ducts' junction. In contrast to the reference methods, post-mortem MRCP did not visualize right and left extrahepatic ducts, and pancreatic ducts in most cats. Based on this study, MRCP with 1.5 Tesla can be regarded as a contributory method to improve the assessment of feline biliary tract and pancreatic ducts when their diameter is >1 mm.

Academics' Experiences in Veterinary Educational Research: Results of an International Survey

Research conducted by the veterinary education community is critical to continual improvement of educational outcomes. Additionally, research productivity is one metric in promotion and tenure decisions. We sought to identify challenges encountered or anticipated when undertaking or planning veterinary educational research (VER), to learn how these challenges might be overcome, and to synthesize tips for success from those who have performed VER. A branching survey was developed and deployed along the authors' worldwide veterinary education contacts in a cascading manner. The survey collected quantitative and qualitative information from participants who had performed VER and those who planned to perform VER in the future. The 258 participants represented 41 countries. Of the participants, 204 had performed VER (79%) and 54 planned to in the future (21%). The median time spent teaching was 14 years, and median time performing VER was 5 years. The most commonly reported challenges in performing VER were lack of funding, lack of time, and difficulties encountered when undertaking a study, including data collection, analysis, and publishing. When asked about overcoming the challenges, a major theme emerged around people, who provided expertise and mentoring. The most commonly reported tip for success was collaboration; 73% of experienced researchers reported people as most helpful upon beginning VER. Collaborators provided diverse help with ideas, study design, statistics, and other aspects. These results suggest that institutions can offer support to academics in the form of small grants, protected research time, writing workshops, and mentorship to assist with the production of meaningful VER.

Diagnostic value of endoscopic retrograde cholangiopancreatography and therapeutic value of endoscopic sphincterotomy in dogs with suspected hepatobiliary disorders

Background

Conventional diagnostic methods have some limitations in diagnosing specific causes of canine hepatobiliary disorders. In the evaluation of the hepatobiliary system in dogs, ultrasonography (US) is the first imaging method of choice. Nonetheless, endoscopic retrograde cholangiopancreatography (ERCP) has also been proven to be a practicable technique for evaluating canine hepatobiliary (endoscopic retrograde cholangiography, ERC) and pancreatic duct (endoscopic retrograde pancreatography, ERP) disorders, providing additional therapeutic options by sphincterotomy (EST). To date, the efficacy and safety of diagnostic and therapeutic ERCP has not been evaluated in veterinary medicine literature. The present study sought to report complications and outcomes of dogs undergoing ERCP and EST, and to assess the usefulness of diagnostic ERCP by comparing the findings of US, ERCP and histopathological findings in liver and pancreas.

Results

This retrospective case series comprises data collected from 15 dogs that underwent successful ERC/ERCP. Nine dogs underwent EST following ERC. US and ERC were best in agreement when assessing the common bile duct. In case of disagreement between the modalities, the ERC findings of the ductal structures were in line with the available pathology findings more often than the US findings, whereas the opposite was noted for the gallbladder. The technical success rates were 88.2% for ERC, 66.7% for ERP, and 81.8% for EST, with no major complications during or immediately after the procedure. Immediate bile flow after EST was recorded in 7/9 dogs but only four showed coinciding clinical and laboratory improvement and four dogs were euthanized within 1-6 days after EST.

Conclusions

US remains a valuable initial diagnostic imaging method for hepatobiliary disorders and allows good assessment of the gallbladder. ERC can serve as a complementary procedure for diagnostic assessment of the hepatobiliary duct disorders. However, in order to improve the outcomes of EST, careful selection of patients for the procedure would require more advanced diagnostic imaging of the hepatobiliary area.

History, clinical findings and outcome of horses with radiographical signs of equine odontoclastic tooth resorption and hypercementosis

The progression of equine odontoclastic tooth resorption and hypercementosis (EOTRH) has not been completely evaluated, and currently, the only effective treatment is extraction of severely affected teeth. We aim to describe how the disease relates to the history and clinical findings and to report on the outcome in individual horses. This case series comprises data collected from 20 horses (age 14–29 years old) with radiographic findings of EOTRH in their incisor and/or canine teeth. Most horses affected with EOTRH in this study were admitted for dental problems, but some for other complaints such as colic. Of the 288 teeth evaluated radiographically, 224 teeth were abnormal. Radiographic findings were most frequently located in the apical aspect and reserve crown of the teeth, and lesions were also commonly found in clinically normal teeth. Histopathology of extracted teeth showed inflammation in the periodontal ligament and revealed that resorption often extended to the dentine. Some owners were unwilling to allow extraction of their horses’ severely affected teeth, even though this treatment has been shown to increase the wellbeing of the horse. As EORTH is a life-long condition, the progression of the disease has to be continuously monitored and the treatments adjusted accordingly.

Teaching Tip-Studying to Become a Veterinarian: A Course for Student Support

During the last decade, concerns over veterinary students' stress have been expressed in several studies, and the need for student support has become evident. In addition, the importance of professional and personal identity development in veterinary curricula has been widely recognized. There is a need to integrate academic and professional skills instruction with training in personal-life balance. Even though tools for student support and stress management exist within universities, reports on active and creative practices in veterinary education are scarce. We report here a course that has been organized twice as an optional part of veterinary studies to provide students with tools for everyday life and personal development toward a future veterinary career. Students defined their own learning objectives in this course, and they reported having received tools and knowledge especially for time management and stress control. The course gave the students an opportunity to step back from their busy schedules, think over their lives and actions, and even take concrete actions that have a positive effect on their well-being. The rich qualitative material collected during the pilot course has been used not only for developing the course further but also for development of the mandatory curriculum.

Students as teachers in an anatomy dissection course

One way to improve students' learning outcomes and well-being is to change teaching practices to allow students to become more active participants. We used an anatomy dissection course to test a cooperative group work method in which first-year veterinary students took turns leading their peer group and were each responsible for teaching the anatomy of a particular topographic region. The important blood vessels, lymphatic system, and nerves of each region of the body were covered. Students felt that exploration of the entire topographic region helped them to acquire a comprehensive understanding of the respiratory apparatus and the cardiovascular and nervous systems. Assigning individual tasks to each group member resulted in sharing the workload equally. Open-ended comments revealed that support from other group members was important for the students' learning experience, but the results also offered insight into a lack of constructive criticism. While teaching was considered challenging, and even a stress factor that hindered learning for some students, group work was generally held to be supportive of learning. The results suggest that more thorough instruction of students in their group work and in their individual tasks is required. Some students experienced difficulty in expressing their concerns openly and in seeking guidance from teachers, demonstrating the need for further investigation regarding students' self-regulation skills. Comments from the open-ended responses suggest that use of a cooperative learning method in anatomy dissection courses not only deepens student understanding of a subject but also offers first-year students an opportunity to practice the generic skills that will be needed in their future profession.

How do veterinary students' motivation and study practices relate to academic success?

The aim of the present study was to explore the factors associated with veterinary students' study success. All veterinary students who began their studies at the University of Helsinki in 2005 participated in this qualitative longitudinal study (N=52). The data consisted of assignments that the students completed at the beginning of their studies and again after three years of studying. The focus was on differences in motivation and study practices as well as possible changes in these over the three-year period. The students were divided into three groups according to their study success (grade point average and study progress). These groups were compared according to group-level differences in the categorized data. The most successful students already described themselves using more positive words than other students at the beginning of their veterinary studies. In addition, they seemed more adaptive in relation to the study's demands. However, there were drops in both the most and least successful students' motivation during their studies. The findings suggest that it is possible to predict forthcoming study problems by analyzing students' study practices and their own descriptions of themselves as learners. In addition, the results show that veterinary students' high motivation cannot be taken for granted. The comparative and longitudinal perspective of the present study can be useful in the development of curricula and in student support.

Clinical significance of ossification of the cartilages of the front feet based on nuclear bone scintigraphy, radiography and lameness examinations in 21 Finnhorses

REASONS FOR PERFORMING STUDY

Research on the clinical significance of ossification of the cartilages of the foot has been limited, despite the common nature of the condition and conflicting reports in previous literature.

HYPOTHESIS

Some radiographic features in the ossification of the cartilages, such as incomplete fusion lines between separate centres of ossification and the ossified base, are of clinical significance.

METHODS

The relationships between radiopharmaceutical uptake in bone phase nuclear scintigraphy at the heels (palmar processes of the distal phalanx, including ossification of the cartilages of the foot), radiographic extent and type of ossification of the cartilages and clinical lameness were evaluated retrospectively in 21 Finnhorses (age > or = 4 years) in a total of 36 front feet.

RESULTS

No significant relationship between height of the ossifications and radiopharmaceutical uptake at the ipsilateral heels existed. Clearly separate centres of ossification were not associated with increased uptake. Moderately increased uptake was suspected to be associated with ossification of the adjacent cartilage in only one foot. Intense uptake was present unilaterally in 4 horses, at one medial and 3 lateral heels. In 2 of these horses, a unilateral palmar digital nerve block relieved the mild lameness; 2 horses had no obvious lameness but had a history of being stiff or having locomotion problems during high speed trot. At 2 of the lateral heels, an incomplete fusion line was present between a large separate centre of ossification and the base, and the third horse had a high sidebone with bony protrusions, suggestive of chronic entheseopathy in a narrow foot. At the medial heel, an oblique radiograph revealed a faint radiolucent line at the base of the ossification. In all cartilages with intense radiopharmaceutical uptake at the heel and/or lameness, the ossified part of the cartilage was wider and more irregular compared to other ossifications of the front feet of the individual.

CONCLUSIONS

Increased radiopharmaceutical uptake, associated with a different radiographic appearance from that of other ossifications of the front feet, was a conclusive sign of clinical significance. Obscure locomotion problems were more commonly associated with ossification of the cartilages than true lameness.

POTENTIAL RELEVANCE

This information is useful in lameness and prepurchase examinations and is likely also to be applicable to other coldblooded breeds used for athletic purposes.

Relationships between students' approaches to learning, perceptions of the teaching-learning environment, and study success: a case study of third-year veterinary students

The relationships among veterinary students' approaches to learning, perceptions of the teaching-learning environment, and study success were evaluated in a demanding, discipline-based curriculum. The aim was to elicit elements for improving student counseling. As part of a large multidisciplinary survey, 36 third-year students (74% response rate) answered a modified version of the Experiences of Teaching and Learning Questionnaire in 2006. In this study, the authors used students' responses to questions regarding examinations and the progress of studies. In addition, students were classified in the large survey into four clusters according to their approaches to studying. Study success was evaluated by exploring the number of study credits students had earned and their grade point averages. The differences in study success between the clusters were not statistically significant, but, in general, students applying a deep approach were most successful, whereas unorganized students applying a deep approach showed the largest variation in study progress. The most commonly mentioned factors for enhancing or impeding study progress were related to the curriculum and to the students' actions or experiences. Unorganized students applying a deep approach seemed to suffer the most from the workload and pressure of progressing in their studies according to a predetermined timetable. These students were also most unaware of the examinations' demands. The findings suggested that, in addition to curriculum development, there is a need to explicitly make students aware of their approaches to learning and to support the development of their study practices.

Estimates of heritability for ossification of the cartilages of the front feet in the Finnhorse

REASONS FOR PERFORMING STUDY

Ossification of the cartilages in the foot is common in coldblooded horses, but prevalence as well as ossification pattern varies between breeds; research on estimation of heritability for the condition has been limited.

OBJECTIVES

Our purpose was to calculate estimates of 1) heritability for ossification parameters of the cartilages in the front feet of the Finnhorse and 2) genetic correlations between the different ossification parameters.

METHODS

Estimates of heritability for different ossification parameters of the cartilages in the front feet and of genetic correlations between different parameters were evaluated in data consisting of dorsopalmar radiographs of the front feet and pedigree up to the fourth generation of 964 Finnhorses (age > or = 2 years; 345 females and 619 males). Ossification at the base of the cartilages and total ossification, including separate centres of ossification, were graded 0-5 according to the most proximal point of ossification and the presence of separate centres of ossification was recorded separately. The data were analysed using a model including a fixed sex-age subclass effect and a random animal effect. Variance and covariance components were estimated with the restricted maximum likelihood (REML) method assuming an animal model.

RESULTS

Females had more ossification than males and this difference increased with age. The ossification in the medial cartilages progressed significantly with age in females but not in males. In the lateral cartilages, the increase in ossification with age was evident in both sexes. Separate centres of ossification were an incidental finding. Estimates of heritability for the ossification parameters varied slightly between the cartilages as well as between the front feet. For total ossification, the estimates of heritability varied between 0.31 (right lateral) and 0.50 (left medial) and were slightly higher for ossification at the base of the cartilages. High genetic correlations were found for total ossification between the medial and lateral cartilages in the foot and for parallel ossification parameters between the right and left foot.

CONCLUSIONS

The estimates of heritability were relatively high, and both cartilages and front feet have a similar genetic tendency to ossify.

POTENTIAL RELEVANCE

This information is useful in further studies assessing other factors contributing to the ossification process and also in the planning and modifying breeding programmes.

Reliability of ultrasonography compared to radiography in revealing intestinal sand accumulations in horses

In order to investigate the reliability of ultrasonography in revealing intestinal sand accumulations, the cranioventral parts of the abdomen of 32 horses (age 3-20 years) with signs suggestive of gastrointestinal sand were examined radiographically and ultrasonographically. The amount of sand and its localisation, relative to the ventral abdominal wall, were evaluated radiographically and graded (scale 0-4). Motility of the intestine and whether it was lying against the ventral abdominal wall were evaluated ultrasonographically and the findings summed and graded (scale 0-3) to express the likelihood of the presence of sand. The ultrasonographic and radiographic grades were significantly associated. Out of 14 horses with a moderate or large ventral sand accumulation radiographically, 13 (92.9%) had a positive sand finding ultrasonographically. Out of 8 horses with no signs of sand radiographically, 7 were considered negative for sand ultrasonographically. The specificity of ultrasonography in detecting sand accumulations was 87.5% (7/8) and the sensitivity 87.5% (21/24). Small and more dorsally located accumulations were more difficult to detect ultrasonographically. Of the horses with a small or moderate amount of sand relatively ventrally or only a small part of sand close to the ventral abdominal wall, 70% (7/10) were considered suggestive or positive for sand ultrasonographically. The ventral aspect of sand accumulations was hyperechoic, causing varying acoustic shadowing and the intestine had decreased or absent motility. Ultrasonography revealed the length of the accumulations but gave very limited information of their height. Ultrasonography is a practical and reliable method for detecting sand accumulations but it cannot replace radiography.

Abdominal radiography in monitoring the resolution of sand accumulations from the large colon of horses treated medically

This retrospective study consisted of 14 horses (age 6 weeks-12 years) with radiographically evident sand accumulations cranioventrally in the abdomen and clinical signs suggestive of sand enteropathy. The horses were treated medically and resolution of sand was monitored radiographically. Routine treatment consisted of psyllium mucilloid, combined with magnesium sulphate and/or mineral oilif needed. Initially, the number, size and shape of the sand accumulations showed large variation and the response to therapy was not predictable based on the initial appearance of the accumulation. In 2 foals, some of the sand was passed and the rest was mixed with other intestinal contents within 2-4 days. Even large accumulations disappeared in 2-4 days with psyllium alone or combined with mineral oil in 4 horses. In another 4 horses, the size of the accumulations decreased but varying amounts remained approximately at the same site, despite treatment for 1-4 weeks, and all these horses also had either gastric or large colon impaction. Three horses had a limited response to psyllium treatment, but the accumulation resolved with repeated doses of magnesium sulphate, with or without mineral oil. One horse did not respond to prolonged laxative treatment but the accumulation resolved on pasture. Clinical improvement was not necessarily related to the resolution of sand. Radiography of the cranioventral abdomen was found to be a useful means for monitoring the resolution of sand and confirming the effect of medical treatment in removing sand from the large colon in the horse.

Ossification of the cartilages in the front feet of young Norwegian coldblooded horses

The purpose of the present study was to evaluate the nature of ossification of the cartilages in the front feet of young, about 2-year-old Norwegian coldblooded horses, and to compare offspring of different sires in this respect. Dorsopalmar radiographs of the front feet of 392 horses (187 female and 205 male) were evaluated for ossification at the base of the cartilage and for separate centres of ossification. The horses were offspring of 45 different sires. Ossification extending above the navicular bone and separate centres of ossification were considered as significant. Minimal to mild ossification at the base of the cartilages was commonly seen, and significant ossification was present in one or more of the cartilages in 11.5% of the horses. The lateral compared to medial cartilages had more ossification and females had more ossification and more separate centres of ossification than males. The prevalence of horses with significant ossifications was significantly higher (46.3%) among offspring of one frequently used stallion than in the group consisting of offspring of 4 other popular stallions (3.5%) and in another group consisting of offspring of other, less frequently used stallions (9.6%). Ossification of the cartilages is considered to have a hereditary background in Norwegian coldblooded horses.

Computed tomographic evaluation of Finnhorse cadaver forefeet with radiographically problematic findings on the flexor aspect of the navicular bone

Computed tomography (CT) was performed on 12 Finnhorse cadaver forefeet with known radiographic changes in the navicular bone (poor corticomedullary junction, irregular appearance of the flexor central eminence, uneven or unequal thickness of the flexor cortex, and/or irregular outline of the proximal or distal flexor margin). The purpose was to confirm the radiographic findings and to investigate if further information of the flexor aspect of the bone could be gained with CT. In CT, the midsagittal outline as well as the internal structure of the bones varied greatly. Different combinations of trabecular and compact bone were seen within the flexor central eminence. Lucencies within the compact bone were commonly present in the proximal half of the eminence, but in five bones lucencies were also identified in the distal half. Due to partial overlapping of the bone and varying bony composition of the eminence, accurate radiographic evaluation of the shape and internal structure of the flexor central eminence was often found to be difficult. The flexor cortex usually appeared to be thinner in CT than in conventional radiographs. Medullary sclerosis and poor flexor corticomedullary junction were commonly overinterpreted radiographically. New bone formation on the proximal flexor margin of the navicular bone was generally visualized in radiographs, but CT allowed also the evaluation of the internal structure of the bone. In one navicular bone, an avulsion fragment on the distal flexor margin was seen in CT images; radiographically this fragment could not be visualized. It was concluded that the flexor aspect of the navicular bone may be difficult to assess reliably with conventional radiography.

Radiographic appearance of the navicular bone and distal interphalangeal joint and their relationship with ossification of the collateral cartilages of the distal phalanx in Finnhorse cadaver forefeet

Radiographic findings in the navicular bone and distal interphalangeal joint as well as the ossification status of the collateral cartilages of the distal phalanx were evaluated in 100 Finnhorse cadaver forefeet. The most common shapes of the proximal articular margin of the navicular bone were convex and straight. Remodeling of the navicular bone was common, especially on the lateral extremity. No bony fragments were identified at the distal flexor margin even though this area appeared irregular in several feet. Several large, rounded or lollipop-shaped synovial invaginations were identified in only six feet. The thickness of the flexor cortex varied considerably, and the corticomedullary junction was uni- or bilaterally indistinct in nine feet. The shape of the sagittal ridge of the flexor cortex was commonly flat but varied. It appeared locally irregular or indistinct in 17 feet, but changes elsewhere along the flexor cortex were rare. Osteophytosis on the dorsal and palmar margins of the distal interphalangeal joint and entheseophytosis on the dorsal aspect of the middle phalanx and on the extensor process of the distal phalanx were common. "Possibly significant" ossification of the collateral cartilages (high sidebones or separate centers of ossification) was present in 36 feet; all grades of ossification in the proximal/palmaroproximal direction as well as palmar ossification were seen. A statistically significant relationship was found between entheseophytosis on the proximal flexor margin of the navicular bone and "possibly significant" ossification. Osteophytosis on the palmarodistal margin of the middle phalanx was more common in feet with a relatively long distal phalanx, suggestive of palmar ossification. Radiographic changes in the navicular bone or in the distal interphalangeal joint did not otherwise appear to be associated with ossification of the collateral cartilages of the distal phalanx in Finnhorses.

Evaluation of the variably ossified collateral cartilages of the distal phalanx and adjacent anatomic structures in the Finnhorse with computed tomography and magnetic resonance imaging

Six Finnhorse cadaver forefeet were selected to represent radiographically different types and grades of ossification of the collateral cartilages of the distal phalanx. These cartilages and adjacent tissues were evaluated with computed tomography (CT) and high field magnetic resonance imaging (MRI). In CT the internal structure of the cartilages was consistent, but in MRI some differences were noted. The shape of the collateral cartilages and their ligamentous attachments varied. The border between ossified and non-ossified cartilage appeared distinct, with considerable variation in the extent of the ossified area in regard to the cross-sectional area of the cartilage. Ossification originating from the palmar processes and extending in the proximal/palmaroproximal direction, without separate centers of ossification, generally appeared smooth and inactive. Palmar ossification followed the irregular shape of the cartilage. Separate centers of ossification had a medullary cavity or were sclerotic. Presence of a medullary cavity or sclerosis were also found at the base of the cartilages. The incomplete fusion lines between separate centres of ossification and the ossified base of the cartilage varied from congruent and inactive to reactive with marked sclerosis, flared margins and parachondral changes. Incomplete fusion may be clinically significant. Local conformational adaptations of the hoof were also documented with extensive ossification of the collateral cartilage.

Effects of sex and age on the ossification of the collateral cartilages of the distal phalanx of the Finnhorse and the relationships between ossification and body size and type of horse

The ossification of the collateral cartilages of the distal phalanx was evaluated in dorsopalmar radiographs of the front feet of 202 Finnhorses (101 females and 101 males, aged six months to 20 years) with reference to the sex, age, body measurements and type of horse. Ossification was more common and more extensive in females than in males from about two years of age. In females, the lateral cartilages were significantly more ossified than the medial cartilages; in males, ossification was more symmetrical in the cartilages of each foot. The amount of ossification increased rapidly during the second and third years of life, and more slowly in adults. The low positive correlation coefficients between ossification and different body measurements of the horse suggested that there was more ossification in large horses, and the correlation between chest-width in adults and the extent of ossification was statistically significant. The working type of horses showed slightly more ossification than trotters and riding horses. Ossification variables, which included ossification at both the base of the cartilage and at the possible separate centres of ossification (total ossification of individual cartilages and "possibly significant' ossification in the front feet), were found to be most satisfactory for expressing the extent of ossification.

Relationship between ossification of the cartilages of the foot and conformation and radiographic measurements of the front feet in Finnhorses

One hundred Finnhorse cadaver front feet were measured and examined both radiographically and visually to report the incidence of various foot problems and their relationship to ossification of the cartilages of the foot. Ossification extending above the proximal border of the navicular bone and/or separate centres of ossification were found in 36 feet, and the lateral cartilages showed more ossification than the medial cartilages. The feet were generally broad with well developed frogs, but the long toe-low heel syndrome was a relatively common finding. Ossification of the cartilages correlated with the length of the heels but was not related to any clinically significant foot abnormalities such as contracted or under-run heels or signs of unequal weightbearing. Ossification of the cartilages did not seem to be either the cause or the result of general conformational adaptations of the front feet.

Radiographic evaluation of ossification of the collateral cartilages of the third phalanx in Finnhorses

Of 462 Finnhorses (age 1-20 years) evaluated and graded (scale 0-5) radiographically for ossification of the collateral cartilages of the 3rd phalanx of the front feet, 22.9% were totally free from sidebones (Grade 0), and 49.1% had minimal or mild ossification (Grade 1 or 2) at the base of 1 or more of the cartilages. Moderate ossification (Grade 3) was present in 10.2% of the horses, whereas ossification was advanced (Grade 4) or extensive (Grade 5) in 17.8%. In most horses > 1 cartilage was affected and 7.6% of the horses had separate centres of ossification in 1 or more of the cartilages. Large sidebones and separate centres of ossification were more common in females than in males (P < 0.001). The incidence of large sidebones was lower in young females (1-3 years) than in mares 4-6 years of age (P < 0.05), but did not increase significantly with age when young horses, 4-6 years of age, were compared with older ones. Grade 4 and 5 sidebones as well as separate centres of ossification were more common in the lateral than in the medial cartilage (P < 0.001), but no difference was observed in this respect between the front feet.