bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inferences from referred clinical cases of osteochondritis dissecans
Authors: McILWRAITH C. W. 
Published: June 2010

SummaryThis report relates to cases of osteochondritis dissecans from my surgical case records. Two categories of OCD were recognised: (1) those showing clinical and radiographic signs, and (2) those showing clinical without radiographic (but arthroscopic) signs. Case material examined included OCD in 318 tarsocrural joints in 225 horses, 261 femoropatellar joints in 161 horses, 170 fetlock joints in 71 horses, and 49 shoulder joints in 43 horses. In 64 tarsocrural joints, other lesions accompanied the OCD lesion including articular cartilage fibrillation (31 joints) and degenerate or eroded articular cartilage (24 joints). In 13 joints, lesions of OCD were present at arthroscopy without being identified by radiographic examination. There was discrepancy in the radiographic demonstration of lateral trochlear ridge lesions and their arthroscopic manifestations. Lesions in femoropatellar joints were divided into three grades and it was common for the arthroscopic lesion to be of a higher grade than the radiographic lesion. Lesions on the medial trochlear ridge with no radiographic manifestations and where the separated articular cartilage was the same thickness as normal articular cartilage were recognised commonly. In the shoulder, the humeral head alone was involved in 12 joints, the glenoid alone in 11 and both humeral head and glenoid were involved in 26 joints. Osteochondritis dissecans of the dorsal aspect of the distal metacarpus and metatarsus was divided into type I, II and III lesions. Type I lesions usually resolved with conservative treatment but type II lesions did not. Based on the arthroscopic findings of these cases, it is noted that instances do occur where there is no thickening of the cartilage, which is inconsistent with previous statements regarding pathogenesis. Breed predispositions were apparent (Standardbred in the hocks, Thoroughbred in the femoropatellar, and metacarpophalangeal/ metatarsophalangeal joints, Quarter Horse and Thoroughbred in the shoulder). The consistent location of lesions within the joint (very close to the limits of articulation) suggests that physical factors may be involved in the pathogenesis. The frequent bilateral nature of lesions in the femoropatellar and tarsocrural joints (and quadrilateral nature in the fetlock joint) while infrequently involving different joints is consistent with a ‘window of vulnerability’ in the endochondral ossification of that specific joint when an environmental insult occurs.
Osteochondrosis in the tarsocrural joint and osteochondral fragments in the fetlock joints in Standardbred trotters. I. Epidemiology
Authors: Sandgren B. , Dalin G. , Carlsten J. 
Published: June 2010

SummaryRadiographic examinations of the tarsocrural and metacarpo/metatarsophalangeal joints were made in two groups of 1.5‐year‐old Standardbreds. One group comprised 674 horses drawn at random from the Swedish population of Standardbred trotters to provide an estimate of the incidence of tarsocrural joint osteochondrosis and osteochondral fragments in the fetlock joints. An additional 119 progeny of 4 stallions which themselves had osteochondrosis or fetlock fragments were included for the study of the distribution of lesions and the characteristics of affected animals, i.e. a total of 793 animals. The radiographic views were chosen to detect osteochondrosis in the tarsocrural joints (OC) and palmar/plantar osteochondral fragments (POF), ununited palmar/plantar eminences (UPE) and dorsal fragments (DF) in the fetlock joints.The incidence of tarsocrural joint OC was estimated as 10.5% while palmar/plantar osteochondral fragments in the fetlock joints were present in 21.5% of the 674 animals.In the group of 793 animals, tarsocrural joint OC was seen in 11.5% of the horses and was found bilaterally in 45% of the affected animals. In the fetlock joints, POF was found in 22.4%, UPE in 4.2% and DF in 4.4% of the horses. One or several of the lesions were found in 35.9% of the 793 horses. There were no significant sex differences in the incidence of OC and POF, but when all lesions were considered males were significantly more often affected than females (40.5%vs31.2%).Of the OC lesions in the tarsocrural joint, 95% were found at the intermediate ridge of the tibia and 5% were seen at the lateral trochlea of the talus. POF and UPE mainly occurred in the hindlimbs. In 75% of the POF cases, the findings were located in the medial part of the joint while UPE findings almost exclusively were found laterally. Horses with UPE had a significantly higher incidence of POF.The incidence of OC in the tarsocrural joint was related to the date of birth and the incidence was higher in the later than in the early part of the foaling season. The incidence of OC findings was also related to body size. Horses affected were taller at the withers and had a greater circumference of the carpus. Synovial effusions of the tarsocrural joint were significantly more pronounced in horses with radiographic signs of OC. In horses with POF and UPE, synovial effusions of the fetlock joints were not more frequent or severe.
Development of osteochondrosis in the tarsocrural joint and osteochondral fragments in the fetlock joints of Standardbred trotters. I. A radiological survey
Authors: Carlsten J. , Sandgren B. , Dalin G. 
Published: June 2010

SummaryIn a longitudinal study 77 Standardbred foals were examined 6 times from birth to the age of 16 months. The radiological examination included 9 views, selected to demonstrate the time of occurrence and the appearance of early radiographic signs of osteochondrosis in the tarsocrural joints (OC), palmar/plantar osteochondral fragments in the fetlock joints (POF) and ununited proximal palmar/plantar eminences of the proximal phalanx (UPE). Subchondral bone defects with a diameter >5 mm and/or osseous fragments were considered significant radiographic findings and were correlated to clinical signs.Eight horses (10.4%) showed OC in the tarsocrural joints at the age of 12 months. All 8 horses showed radiographic changes indicating early OC lesions that were detectable before the age of 3 months. In 4 of these horses subchondral bone defects and/or fragments at the intermediate ridge of the distal tibia were visible before 1 month of age. Eleven horses showed radiographic changes first detected between 1 and 3 months of age that reverted to normal appearance at 8 months of age. In no case was a significant radiographic finding first detected between the age of 8 and 16 months. The radiographic findings of permanent hock OC were significantly correlated with the presence of tarsocrural joint effusions but did not correlate with lameness.At the age of 12 months, 11 horses (14.3%) showed significant radiographic changes with defects and/or osseous fragments in the metacarpo‐ and metatarsophalangeal (fetlock) joints. In all of these horses early indications of these changes were detected before the age of 5 months. In 7 horses early radiographic signs of abnormal ossification reverted to a normal appearance before the age of 8 months. No additional significant radiographic findings were detected after the age of 8 months. There was no correlation between radiographic findings and fetlock joint synovial effusion or lameness.Osteochondrosis of the tarsocrural joints and palmar/plantar intraarticular fragments in the fetlock joints develop very early in life and can be regarded as being permanent if present at 1 year of age.
Development of osteochondrosis in the tarsocrural joint and osteochondral fragments in the fetlock joints of Standardbred trotters. II. Body measurements and clinical findings
Authors: Sandgren B. , Dalin G. , Carlsten J. , Lundeheim N. 
Published: June 2010

SummaryIn a stud survey, 77 Standardbred foals (35 colts, 42 fillies) were examined 6 times from birth to the age of 16 months. In addition to the radiographic examination of the tarsocrural and fetlock joint areas, the horses were measured for height at the withers and at the croup, the circumference of the girth, carpus and cannon, and the length of cannon, and their conformation assessed according to a standardised protocol. The examination was completed by clinical examination, including thorough palpation of the extremities. All examinations were done by the same person. The foals were weighed each month. The metric observations were precorrected according to a model including the effects of sex, year of birth and the regression on individual recording age.Eight foals (4 colts, 4 fillies) that developed radiographic signs of tarsocrural joint osteochondrosis (OC) had a higher body weight at birth (54.0 kgvs51.0 kg) and continued to be heavier and have a significantly higher average daily weight gain than did unaffected foals (12 months 337.8 kgvs316.8 kg, 0.80 kg/dayvs0.74 kg/day). They also had a larger frame than did horses without tarsocrural OC, including a greater height at the withers and at the croup, and had a markedly larger circumference of the carpus and cannon.From 5 months of age onwards, there was a significantly higher incidence and more severe degree of synovial effusion in the hock joint in horses with OC. Enlargement of the distal physeal region of the metacarpus was more common and more pronounced between 3 and 8 months of age in horses with tarsocrural joint OC.Eleven foals (3 colts, 8 fillies) with fetlock findings, palmar/plantar osteochondral fragments (POF) and/or ununited palmar/plantar eminences (UPE), were slightly lighter (birth weight 50.8 kgvs52.0 kg, 12 months 316.3 kgvs321.6 kg). The average daily weight gain, as well as the different body measurements, were similar in affected and in unaffected horses. There was no relation between radiological findings of POF or UPE and the degree of synovial effusion or other clinical signs in the fetlock area, including the distal physeal region.The early radiological signs of OC and the observed difference in body size at birth indicate that the pregnancy period and the first months in the foal's life are of major importance for the development of OC. The differences in body weights, body measurements and clinical signs between horses affected by tarsocrural OC and fetlock POF or UPE are indications that the pathogenesis of these lesions differs.
Natural history of femoropatellar osteochondrosis in three crops of Thoroughbreds
Authors: McIntosh S. C. , McIlwraith C. W. 
Published: June 2010

SummaryThis paper reports the incidence of radiographic lesions of osteochondritis dissecans (OCD) of the femoropatellar joint relative to the development of clinical symptoms in the 1989 foal crop, and the clinical symptoms, radiographic features and outcome of the 1990 and 1991 foal crops affected with OCD at the same Thoroughbred farm. In the 1989 foal crop, 23 of 96 yearlings were identified with clinical and/or radiographic signs of OCD. They had an average age of 12.6 months at identification. Eighteen cases had clinical and radiographic signs of osteochondrosis, 3 had clinical signs in the stifles without radiographic signs and 2 had radiographic signs of osteochondrosis but no clinical signs (one eventually became symptomatic). Of the cases with clinical signs but no radiographic signs, one subsequently developed radiographic signs and the other 2 had bilateral clinical signs and unilateral radiographic signs. Seven horses had surgery at the time of clinical and radiographic diagnosis; 5 subsequently raced, 1 is in training and 1 has persistent problems. Of 11 cases not operated initially, 6 raced, 3 had no follow‐up, 1 became a jumper and 1 was operated later. In the 1990 foal crop, 13 of 120 foals were diagnosed with femoropatellar OCD. The average age at diagnosis was 9 months. Nine of the foals had radiographic lesions, 3 had equivocal radiographic lesions (1 progressed to an obvious lesion) and 1 had no radiographic lesions of the femoropatellar joint (but did have them in the fetlocks). All but one horse were treated conservatively. Of the horses with radiographic lesions initially, 2 have raced, 2 are still unraced, 3 have lameness and 2 were used for non‐racing careers. One horse had equivocal lesions initially but these progressed. In the 1991 foal crop, there were 16 cases of femoropatellar OCD diagnosed out of 125 foals. The average age at clinical recognition was 6 months. Ten horses had radiographic lesions at the time of initial diagnosis, 5 had no radiographic lesions initially but subsequently developed them, and 1 never had a radiographic lesion. Four horses were sold as yearlings reportedly without synovial effusion or lameness, 1 died of unrelated causes, 10 are currently racing or training and 1 subsequently developed OCD of the metatarsophalangeal joints.
Correlative study of defective cartilage and bone growth in foals fed a low‐copper diet
Authors: Hurtig M. , Green Sherril L. , Dobson H. , Mikuni‐Takagaki Y. , Choi J. 
Published: June 2010

SummaryA blind randomised study using two groups of age‐ and sex‐matched Quarter Horse foals was conducted by feeding a low copper diet containing 8 ppm of copper (Cu) and a control diet containing 25 ppm. Foals in the low‐Cu group had declining liver Cu values and developed osteochondritis (OCD), epiphysitis and limb deformities over a 6‐month period. Erosion and separation of cartilage from the subchondral bone in the dorsal facets of the cervical spine were the most consistent post‐mortem lesions. Foals fed the high‐Cu diet had no significant musculoskeletal lesions. Scoring of standing lateral cervical radiographs was a moderately sensitive (0.68) and specific (0.70) test and had moderate agreement with post‐mortem findings (κ = 0.35). Technetium scintigraphy of the limbs and cervical spine failed to detect occult or known lesions in the limbs and cervical spine. Microscopic examination of growth plates and metaphyseal bone from affected foals showed that fractures disrupted or displaced the normal growth plate architecture and interfered with orderly bone growth, similar to Cu deficiency in cattle. Bone morphometry indicated there was less subchondral bone volume in the distal cannon bone (P<0.005). Similarly, there were fewer newly formed trabeculae in the primary spongiosa (P<0.02) and metaphysis (P<0.07) of the distal tibia in the Cu‐deficient foals. Biochemical studies were limited to 4 control and 6 low‐Cu foals. Of the 6 low‐Cu foals, 4 were severely affected with multiple lesions. These assays showed significantly reduced collagen cross‐linking in the cartilage and bone articular cartilage of severely affected foals. The control group foals had articular and growth plate cartilage explants in tissue culture released increased amounts of gelatinase and proteoglycanase, reflecting increased matrix remodelling. Traditional concepts of osteochondritis have implicated a non‐specific defect in endochondral ossification. This study proposes a relationship between low copper intakes in fast‐growing horses, inferior collagen quality, biomechanically weak cartilage and OCD lesions. While all foals in the low‐Cu group were affected, only 5 of the 9 developed clinically significant lesions. This indicates that factors other than nutrition, such as individual variation in growth rate or genetic potential, still influence the expression of this syndrome.
Effects of dietary energy and protein on induction of dyschondroplasia in foals
Authors: Savage C. J. , McCarthy R. N. , Jeffcott L. B. 
Published: June 2010

SummaryThirty mixed‐bred foals aged 2.5–6.5 months (mean 4.6 ± 1.0 months) with no clinical or radiographic signs of dyschondroplasia (DCP) were fed one of four diets for 16–18 weeks. Twelve foals were fed a Control diet which comprised ˜100% of the NRC recommendations for dietary energy (DE) and crude protein (CP). Six were fed a diet with ˜126% of NRC levels for CP and 12 foals were fed a diet with 129% of NRC levels for DE. The diets comprised 3 different formulations of rice‐based pellets with added maize oil for the High DE diet, and oaten chaff.Average daily gain, humeral length and wither height were slighly, but not significantly, different in the foals on the High DE diet than in those fed the Control or High CP diet. Clinical and radiographic signs of DCP were seen in 6 out of 12 foals fed the High DE diet. Not one of the foals fed High CP or Control diets showed any clinical and radiographical signs of DCP. The number and severity of DCP lesions found at post‐mortem examination were much greater in the High DE foals than in the Control and High CP foals. Multiple lesions of DCP were detected in 11 foals fed the High DE diet, in 1 foal fed the High CP diet and in 1 foal fed the Control diet. Histological lesions of DCP were confirmed in 18 foals; in all 12 of the High DE foals, 4 of the 6 High CP foals and 2 of the 12 Control foals. The number of histological lesions of DCP were significantly greater in the High DE foals than in the Control group (P < 0.0001). The incidence of lesions of DCP in the foals fed High CP was not significantly different from that in the Control foals (P = 0.11).
Effects of dietary phosphorus and calcium on induction of dyschondroplasia in foals
Authors: Savage C. J. , McCarthy R. N. , Jeffcott L. B. 
Published: June 2010

SummaryThirty mixed‐bred foals aged 2.5–6.5 months (mean age 4.4 ± 1.0 months,) with no clinical or radiographic lesions indicating dyschondroplasia (DCP) were each fed 1 of 4 diets for 16–18 weeks. Twelve foals were fed a Control diet according to NRC recommendations. Six foals were fed a diet ˜388% NRC recommended level for P; another 6 foals were fed a diet with ˜342% NRC level for Ca and the remaining 6 foals were fed a diet which contained both ˜342% NRC level for Ca and ˜129% NRC level for digestible energy (DE). Diets were formulated using different rice‐based pellets and oaten chaff, with added maize oil for the High DE diet, and additions of limestone (CaCO3) for the High Ca and sodium monophosphate (5.5% of the pellet) for the High P.Foals fed excess DE (High Ca/DE group) had slightly greater average daily gains, humeral lengths and wither heights, but these were not significantly different from foals fed the Control diet. Clinical and radiographic signs of DCP were seen in 7 foals; 4 foals fed High P and 3 foals fed High Ca/DE. Suspicious joint lesions of DCP were identified atpost mortemin 13 foals (1 Control, 5 High P, 2 High Ca, 5 High Ca/DE). Histologically confirmed lesions of DCP were found in multiple joints and growth plates in 15 foals (2 Control, 5 High P, 2 High Ca, 6 High Ca/DE). The lesions were more numerous and severe in the foals fed High P and High Ca/DE than in the foals fed the Control and High Ca diets. High levels of dietary Ca did not appear to induce lesions of DCP in foals fed ˜100% NRC recommendation for dietary DE, or reduce the incidence in foals concurrently fed high dietary DE. High levels of P intake resulted in the formation of lesions in foals fed the basal level of DE (˜100% NRC DE), although the mechanism by which this occurred has not been elucidated.
Preliminary results of demineralised bone matrix implantation in horses
Authors: Douglas Janet , Clarke A. F. 
Published: June 2010

SummaryIn rats the subcutaneous or intramuscular implantation of allogeneic demineralised bone matrix (DBM) induces host mesenchymal cells to undergo endochondral ossification. In normal rats this process adheres to a rigid timetable, cartilage being present by Day 7 and bone by Day 12. This technique was applied to horses. Demineralised bone matrix from 3 different equine donors, a neonate, a yearling and a 4‐year old, was implanted intramuscularly or subcutaneously in 4 different equine hosts, aged 6 weeks to 6 years. Implants were removed 10–37 days later. No evidence of endochondral ossification was detected in any of the implants. As a control experiment, DBM prepared from rats was implanted into allogeneic hosts using the same bone preparation and implantation technique as was used in the horses. Endochondral ossification was induced in the rats, and the process followed the expected time course. Preliminary results suggest that hyaline cartilage formation does not occur in horses within 37 days. The present study does not exclude the possibility that endochondral ossification may occur in horses if longer implantation periods or different methods of DBM preparation are used.
Utilisation of an accelerometric device in equine gait analysis
Authors: BARREY E. , HERMELIN M. , VAUDELIN J. L. , POIREL D. , VALETTE J. P. 
Published: June 2010

SummaryAn accelerometric device was developed for evaluating the gait of young horses in field situations. Some measurements and data analysis were made to show its potential applications in gait analysis. The transducers consisted of two accelerometers measuring acceleration along the longitudinal and dorso‐ventral axes of the horses. They were put into a leather pocket applied over the sternum by means of an elastic girth fastened onto the horse. This accelerometric belt was connected to a light weight radio telemetric system. The signals were transmitted to a receiver connected to a portable microcomputer. An alternative method to use this device was to connect it directly to an analog‐digital converter of the microcomputer. The maximum data acquisition rate was 50 Hz for each accelerometer using the telemetric system and 3500 Hz using direct connection. The accelerometric device could be used either on a treadmill or in field situations. Longitudinal and dorsoventral acceleration of the sternum provided some information about basic temporal stride kinematics and kinetics of a running horse. Two tests illustrated the usefulness of the accelerometric belt to investigate the velocity‐dependent changes in stride frequency and longitudinal acceleration, and the gait asymmetry of a lame horse. Three signal analysis procedures were used for data analysis, respectively: Fourier analysis, peak‐finding and autocorrelation functions. It was concluded that the accelerometric belt allows an objective study of some basic characteristics of the horse locomotion in field situations. It could be useful to test young horses provided that standardised protocols are developed to measure and analyse the acceleration data.
Surface strain on the dorsomedial metacarpus of yearling Thoroughbreds at different speeds and gaits on a treadmill
Authors: DAVIES H. M. S. , McCARTHY R. N. 
Published: June 2010

SummaryStacked rectangular rosette strain gauges were used to measure surface bone strain on the dorsomedial cortex of the third metacarpal bones in 6 yearling (16 to 19 months old) Thoroughbred horses during exercise on a treadmill. The peak principal compressive and tensile strains, angle of the peak strains and strain rate during loading were calculated and compared with speed and gait. At speeds ranging from 4 to 16.5 m/s there was compression of the dorsomedial cortex of the metacarpus and the magnitude of compression and rate of compression were proportional to the speed of exercise. At the walk (2 m/s) tension was recorded in some strides. The mean maximum compressive strains in the 6 horses were −966 μstrain at 2 m/s; −1630 μstrain at 4 m/s; −2172 μstrain at 6 m/s; −2857 μstrain at 8 m/s; −3500 μstrain at 10 m/s; and −3911 μstrain at 12 m/s. Recordings from 3 horses gave a mean −5028 μstrain at 14 m/s. One horse gave a mean −6296 μstrain at 16.5 m/s. These strains were all about 25% higher than those recorded from the metacarpus of adult Thoroughbreds under similar exercise conditions. It was concluded that the higher strains may predispose the young Thoroughbred racehorse to dorsal metacarpal disease.