Occurrence of vertebral osteophytosis in a museum sample of white-beaked dolphins (Lagenorhynchus albirostris) from Danish waters.

The occurrence of pathologic new bone formation in the vertebral column was studied in 46 skeletons of the white-beaked dolphin (Lagenorhynchus albirostris) stranded in Denmark between 1903 and 2002 and held in the collections of the Zoological Museum, University of Copenhagen. New bone formation was evident in 18 (72%) of 25 physically mature specimens and in one of 21 physically immature specimens. This pattern of occurrence is consistent with spondylosis deformans, which is caused by degeneration of the intervertebral disk. In general, females seemed to be more susceptible, exhibiting a higher number of affected vertebrae and more severe cases. Lesions were predominantly detected in the lumbar and cranial caudal vertebra. Data on blubber thickness were available for part of the sample; one of the most heavily afflicted specimens had the thickest recorded blubber, indicating that secondary bone formation leading to blocks of fused vertebrae had not necessarily impaired the body condition of afflicted specimens. However, age determinations conducted on the sample revealed that none of the most severe cases occurred among the oldest animals, implying that these severe cases may cause premature fatality.

Acromegaly due to a somatroph adenoma in a dog.

A 10-year-old uncastrated male Dalmatian dog was referred for gait abnormalities consisting of chronic progressive stiffness and rigidity. Other symptoms were polyphagia associated with weight gain, polyuria and polydipsia, excessive panting, and an inspiratory stridor. The owner had noticed progressive thickening of the skin and enlargement of the tongue over the last 3 years. Physical examination revealed thickening of the skin, redundant skin folds, and enlargement of the tongue. The only remarkable abnormalities found on routine laboratory examination were mild anaemia and an increased serum fructosamine concentration. Circulating concentrations of total thyroxine, free thyroxine, and cTSH, and the results of an ACTH stimulation test were all within reference ranges. The basal serum growth hormone (GH) concentration was markedly elevated (23microg/l) and did not decrease during a glucose tolerance test or after somatostatin administration. The serum insulin-like growth factor-1 concentration was also markedly elevated (1254microg/l). Basal serum insulin concentration was high (95mU/l) and insulin concentrations increased considerably after glucose loading, consistent with insulin resistance. Abdominal ultrasonography showed no abnormalities. Survey radiographs of the vertebral column showed severe spondylosis deformans extending from the cervical to the lumbosacral spine. CT scanning of the skull showed an enlarged pituitary gland with normal enhancement pattern. On post-mortem examination, the entire vertebral column appeared as a single and inflexible structure due to the presence of multiple fused osteophytes. The pituitary gland contained an acidophilic adenoma that immunostained positively for GH (and negatively for ACTH and alpha-MSH). In conclusion, this Dalmatian dog with acromegaly and insulin resistance represents the first case of GH hypersecretion proven to be due to a somatotroph adenoma.

Evaluation of the association between spondylosis deformans and clinical signs of intervertebral disk disease in dogs: 172 cases (1999-2000).

OBJECTIVE: To evaluate the association between spondylosis deformans and clinical signs of intervertebral disk disease (IVDD) in dogs. DESIGN: Retrospective case series. ANIMALS: 210 dogs. PROCEDURE: Records of 172 dogs with clinical signs of IVDD and 38 dogs with other neurologic disorders were reviewed. Signalment, sites of spondylosis, severity of associated osteophytosis, type of disk herniation, and duration of signs were recorded. RESULTS: Dogs with IVDD had significantly fewer sites of involvement and lower grades of spondylosis deformans, compared with those in the non-IVDD group. When groups were adjusted for age and weight via multivariate linear regression, there were no differences in severity of osteophytosis or number of affected sites. Dogs with type II disk disease had higher numbers of affected sites and more severe changes, compared with dogs with type I disk herniation. There was no difference between groups in the rate at which IVDD was diagnosed at sites of spondylosis, compared with the rate at which IVDD was diagnosed in unaffected disk spaces. Areas of spondylosis were closer to sites of IVDD that elicited clinical signs than to randomly chosen intervertebral spaces, and distances between sites of spondylosis and sites of IVDD had a bimodal appearance. CONCLUSIONS AND CLINICAL RELEVANCE: An association may exist between radiographically apparent spondylosis and type II disk disease; type I disk disease was not associated with spondylosis. Spondylosis in radiographs of dogs with suspected type I disk disease is not clinically important. Spatial associations among sites of spondylosis and sites of IVDD may be coincidental or associated with vertebral column biomechanics.

Acquired structural kyphoscoliosis in a captive adult female rhesus macaque (Macaca mulatta).

A female, wild-caught, rhesus macaque (Macaca mulatta), in captivity for 23 years and estimated to be older than 26 years, had an 8-year history of progressive spinal curvature. Scoliosis was initially noted 1 year after a therapeutic bilateral ovariectomy to treat endometriosis. Eight years after the initial diagnosis, the curvature had progressed to a structural (nonflexible), lumbar scoliosis with a curvature to the left and a structural thoracolumbar kyphosis. The spinal curvature was characterized radiographically by a severe, major lumbar curve to the left with vertebral rotation and severe thoracolumbar kyphosis. The Cobb method of measurement identified a major left lumbar curve of 80 degrees. When the animal's condition deteriorated, the animal was euthanized, and a necropsy with postmortem radiographic and microscopic examination was performed. Radiographically and grossly, multiple intervertebral disc spaces were narrowed along the entire spine with ventral bridging intervertebral spondylosis of the lumbar spine. Radiographically, vertebral bodies appeared to be less radiodense and multiple features of degenerative disc disease were present. No clinical evidence of concurrent neuromuscular or mesenchymal disease was noted, and development of lesions after bilateral ovariectomy suggested the kyphoscoliosis was secondary to osteopenia that developed as the result of a surgically induced estrogen deficiency.

Spinal spondylosis and acute intervertebral disc prolapse in a European brown bear (Ursus arctos arctos).

A 22-year-old male European brown bear (Ursus arctos arctos) was presented to the Onderstepoort Veterinary Academic Hospital after an acute onset of hind limb paralysis 4 days earlier. Previous radiographs revealed marked degenerative joint disease of the stifles, tarsi and digits. The clinical findings were consistent with acute disc prolapse. Lateral radiographs of the entire vertebral column were made as well as ventrodorsal pelvic radiographs. The latter were within normal limits. The vertebral column revealed multiple lesions consistent with chronic and acute disc herniations. Lateral compression of the caudal lumbar nerve roots could not be ruled out. Owing to multiple significant findings of the vertebral column and the poor prognosis for full recovery after surgery, the bear was euthanased. The diagnosis of an acute disc prolapse and multiple chronic disc herniations was confirmed on necropsy.

Age-related changes in osteometry, bone mineral density and osteophytosis of the lumbar vertebrae in Japanese macaques.

The age-related changes in lumbar vertebrae were studied in 77 young/full adult Japanese macaques (Macaca fuscata) (40 females, 37 males), in terms of their morphometry, density and osteophytosis, and the interrelationship between these three aspects. The most common age-related pattern of morphometric changes was an initial increase during young adulthood until reaching the peak and then a subsequent decrease with age. Most of the peaks were in the age group 15-20 and 10-15 years in females and males, respectively. In both sexes, the age-related decrease in the vertebral body depth (ventro-dorsal) was greater than in the height and width. The ventral height of the vertebral body relative to the dorsal height continuously decreased with age. The trabecular bone mineral density (BMD) continuously decreased after young adulthood. However, the magnitude of the decreased trabecular BMD with age was greater in females than in males, especially in the older age groups. Osteophytosis clearly increased with age in both sexes, but males showed an earlier appearance of osteophytes and females tended to have more severe osteophytes from 15 years old upwards. A correlation between the osteometry, density, and osteophytosis severity appeared in all vertebrae, but not all of these reached statistical significance after controlling for the influence of age. Although Japanese macaques showed the higher prevalence and rapid increase of osteophytosis, a similar age change profile was observed in the lumbar vertebrae of Japanese macaques and humans.

Spontaneous degenerative spinal disease in the laboratory rabbit.

The spines of 35 rabbits (32 New Zealand white and 3 AC/J), ranging in age from 3 months to 8 1/2 years, were investigated systematically for spontaneous degenerative changes. Three types of lesion were observed. (1) The nucleus pulposus underwent chondroid metaplasia throughout the length of the vertebral column by the age of 2 years. (2) Hydroxyapatite deposition was found in the nucleus pulposus in 12 of 20 animals examined roentgenographically. The lesion occurred principally in the distal thoracic segments and was first observed in 3-month-old rabbits. (3) Spondylosis occurred in each of four macerated spines from animals greater than 24 months old. Portions of the spine spared by disc calcification were affected.

Disseminated skeletal lesions associated with pathogenic actinomycetes in a Pygmy hog (Sus salvanius).

The clinical and pathological features of an unusual crippling bone disease in an adult male Pygmy Hog, Sus salvanius, born the smallest in a litter of five and representing the rarest of the known living Suidae, are described. Radiological studies revealed severe spondylosis deformans and focal sharply demarcated radiolucencies in virtually the whole skeleton, but particularly in the bones of the skull, the processes of multiple vertebrae, the ribs, scapulae and parts of the humeri and femora. The clinical chemistry measurements were indicative of pathological lytic processes in the skeleton. The focal bone lesions consisted of caseous necrosis, dystrophic calcification and peripheral fibroblastic demarcation. They contained colonies of filamentous bacteria identified as members of the Order Actinomycetales. Case history evidence suggests that the infection may have resulted from repeated skin trauma inflicted by litter-mates.

Differentiation between lumbosacral transitional vertebrae, pseudolumbarisation, and lumbosacral osteophyte formation in ventrodorsal radiographs of the canine pelvis.

Ventrodorsal radiographs of the pelvis (n=150) of Rottweilers, Golden Retrievers, and German Shepherd dogs and macerated spines (n=800) from a variety of breeds were assessed for morphological evidence of lumbosacral transitional vertebrae as well as for factors that might lead to radiographic misinterpretation of this condition. Those alterations closely resembling the radiographic appearance of transitional vertebrae were identified to be: (1) calcification of the dorsal and ventral sacroiliac ligaments (=pseudolumbarisation), which might be interpreted as a costal process at S1 (or the corresponding vertebra in cases of numerical vertebral variations); and (2) osteophyte formation at the lumbosacral junction simulating separation of the cranial articular processes from the assembly of the sacral wing as seen in transitional vertebrae.

Symposium on back problems in the horse. (2) The diagnosis of diseases of the horse's back.

A description of some of the clinical features of low back pain in the horse has been given and a number of methods for assisting diagnosis considered. As well as a complete clinical examination both at rest and during exercise, a useful diagnostic aid in some chronic cases was the injection of local anaesthetic into the interspinous spaces. A laboratory examination, including haematological and biochemical profiles, was undertaken in all cases. The serum enzymes GOT and CPK were particularly valuable as an aid to diagnosis in atypical tying-up. A technique for radiography of the vertebral column of the mid back in the standing position and of the pelvic and sacroiliac regions of the anaesthetised horse was described using a Siemens Triplex Optimatic 1023 machine. Some of the radiological features of the vertebral column were considered and a breakdown of the diagnosis of 110 referred back cases. The most important conditions included muscle strain, crowding and overriding of the dorsal spinous processes in the mid back, spondylosis, undue curvature of the spine and vertebral fractures.

Diagnosis of cauda equina abnormalities by using electromyography, discography, and epidurography in dogs.

Electromyography (EMG), L7-S1 discography and epidurography were investigated in 15 dogs with clinical signs of cauda equina dysfunction and in 7 control dogs without such clinical signs. Electromyography of paraspinal and pelvic limb muscles was done in 13 of 15 affected dogs. An L7-S1 discogram followed by an epidurogram was performed in all 22 dogs using 20% iopamidol. Results of discograms, epidurograms, and gross necropsy examinations were normal in six of seven control dogs. The one dog in which these studies were abnormal had a mild L7-S1 disc protrusion that did not result in nerve root compression at necropsy. Electromyographic analysis was 100% accurate in predicting the presence or absence of cauda equina disease. None of the results of discograms were falsely negative. Twelve of 15 discograms in clinically affected dogs indicated dorsal disc protrusion, but 2 of these protrusions were found to be noncompressive at surgery (13% error). Abnormal epidurograms occurred in 9 of 15 clinically affected dogs. There was one false positive and two false negatives (20% error). Electromyography was a sensitive screening technique for the presence of cauda equina disease. Discography may be more sensitive for detection of L7-S1 disc protrusion than epidurography. An abnormal radiographic contrast study of the cauda equina may only be useful when combined with an abnormal EMG.

Prevalence of spondylosis deformans and estimates of genetic parameters for the degree of osteophytes development in Italian Boxer dogs.

The aim of this study was to assess the prevalence of spondylosis deformans and to investigate genetic aspects of the degree of osteophytes development (DOD) in the Italian Boxer dog population. A total of 849 Boxer dogs was radiographed on the thoracic, lumbar, and sacral regions of the spine and scored for DOD. Grading of DOD was performed for all 20 intervertebral sites comprised within the first thoracic site (site T1-T2) and the site between the seventh lumbar and the first sacral vertebra (site L7-S1). Scores for DOD ranged from 0 (no osteophytes development) to 3 (presence of a bony spur formed by osteophytes on adjoining vertebrae). The first five thoracic sites exhibited no variation for DOD and were not considered in the analysis. The prevalence of spondylosis deformans was 84%, and frequency of dogs showing at least one intervertebral site that scored 3 for DOD was 50%. Scores for DOD at different sites were analyzed as different traits. Nongenetic effects influencing DOD scores were sex, age at screening, and the kennel. Posterior densities of heritability (h2) were estimated using a univariate Bayesian analysis. Eight sites exhibited a posterior probability greater than 0.8 for h2 > 10% and were considered in a multivariate restricted maximum likelihood analysis. Estimated h2 from multivariate analysis ranged from 25 to 48% (SE from 5 to 7%). Three sites exhibited h2 estimates greater than 40%. Genetic correlations for DOD scored at different sites ranged from 0.07 to 0.96. All thoracic sites had estimated correlations larger than 0.85 with other thoracic sites. Genetic correlation between the first and the second lumbar site was 0.91. Correlations between thoracic sites and the first two lumbar sites ranged from 0.5 to 0.9. Sites L6-L7 and L7-S1 also exhibited weak relationships with all remaining sites. Breeding values of dogs for DOD at the eight sites were predicted using estimated covariance matrices. A selection index for DOD was computed from predicted breeding values and a set of relative weighting factors produced by a panel of veterinarians. The index was the most important effect influencing phenotypic differences between dogs for average DOD score, number of affected sites, and number of sites with a DOD score > 1 (P < 0.001). The degree of osteophytes development is a trait showing exploitable additive genetic variance, and breeding programs for decreasing prevalence and severity of spondylosis deformans might focus on this trait.

Arthropathy in white-tailed deer and a moose.

Degenerative lesions were found in the skeletal system of 20 to 128 white-tailed deer (Odocoileus virginianus) examined. Similar changes were found in an aged male moose (Alces alces). Arthropathy involving the stifle joint was present in 60% (15/25) of male deer 4 years of age or older, and in 16.7% (4/25) of females in the same age range. Vertebral osteophytes were not found in any of 62 female deer, nor in male deer less than 6 years of age, but were present in 50% (7/14) of males 6 year of age or older. The possible etiology and significance of the conditions are discussed.

A case of spondylosis deformans in the defleshed skeleton of a wild coyote and its significance to osteopathologic interpretation.

The skeleton of a wild coyote (Canis latrans), collected in Alturas, California (USA), in 1940 and reported to have died of a blowfly infection, was analyzed. The axial components, primarily a series of fused and deformed vertebrae, had classic osteological indications of spondylosis deformans, a trauma-induced disorder. Severe crippling due to a crushing-type strain was identified as the primary pathological condition to which the coyote succumbed, with death hastened by vertebral degeneration and the complicating infection.

Cervical dorsal spondylosis with spinal cord compression in a black swan (Cygnus atratus).

Cervical dorsal spondylosis with spinal cord compression in a black swan (Cygnus atratus) was confirmed radiographically and morphologically. Clinically ataxia was associated. Noninflammatory, degenerative changes of the synovial joint cartilage were associated with the spondylosis.

Osteochondrosis, degenerative joint disease, and vertebral osteophytosis in middle-aged bulls.

Twenty-five middle-age (65 +/- 18 months) dairy bulls sent to slaughter for nonmedical reasons were evaluated for joint disease in the stifle and the lumbar vertebrae. Fourteen bulls had degenerative joint disease and 3 had osteochondrosis (osteochondritis dissecans) of the distal end of the femur. These lesions predominantly involved the lateral trochlear ridge. Twenty-one bulls had vertebral osteophytosis. Degenerative joint disease and vertebral osteophytosis were common in these middle-aged bulls and, even when severe, were rarely associated with lameness.

Cauda equina compression from lumbosacral malarticulation and malformation in the dog.

Compression of the cauda equina from subluxation, stenosis, or spondylosis of the lumbosacral articulation was found in 20 dogs, 13 of which were German Shepherd Dogs or crossbred German Shepherd Dogs. Pain, posterior paresis, and urinary or fecal incontinence were the most frequent problems associated with the compression. Dorsal laminectomy was performed on 13 cases, with good to excellent results on 10 of these.

Bovine arthritides. Classification, diagnosis, prognosis, and treatment.

Bovine arthritides are an important aspect of food animal practice, and a good understanding of these conditions allows the practitioner to develop effective treatment regimens. This article discusses the complexities of joint diseases and the problems associated with their diagnoses and treatments.

Management of cervical spondylopathy-associated intervertebral, disc protrusions using metal washers in 78 dogs.

Intervertebral 7.5 mm (n = 75) and 6.0 mm (n = 22) metal washers were used to distract intervertebral spaces in 78 consecutive cases of canine cervical spondylopathy-associated disc protrusions, where myelography had demonstrated traction-responsive spinal cord compression. Nineteen dogs had compressive lesions at two sites. Fifty lesions were evaluated myelographically on immediate postoperative radiographs; of these, 32 compressions had been eliminated and 18 had been reduced. Euthanasia was performed in nine dogs within six months of surgery and 15 dogs had varying degrees of neck pain during this period. Long-term follow-up information was available on 65 dogs nine to 70 months following surgery (median 32 months). Sixty-three of these dogs improved postoperatively. Neurological function subsequently deteriorated in 17 dogs 10 to 59 months following surgery (median 34 months). Eight of these 17 cases had further myelographic investigations and all had additional disc protrusions with no evidence of cord compression at the previous sites of surgery. The remaining nine cases had a deterioration in hindlimb function but were not investigated further.

Comparison of two surgical techniques for the management of cervical spondylomyelopathy in dobermanns.

A study was undertaken to compare the efficacy of two surgical techniques for the treatment of caudal cervical spondylomyelopathy (CCSM): ventral decompression (slot) and vertebral distraction and stabilisation with a screw and washer (screw/washer). Twenty-eight dobermanns managed surgically for disc-associated CCSM during a four-year period were studied retrospectively. The maximum postoperative period was 40 months. Cases were excluded if a minimum follow-up of 24 months after surgery could not be made. A 'slot' took a longer time to perform and had a higher rate of immediate postoperative deterioration. Duration of hospital stay was similar for both procedures. At six months after surgery the two techniques were comparable; 12/14 (screw/washer) and 13/14 (slot) patients were deemed to have a satisfactory outcome. Recurrence of cervical spinal cord disease was higher in the screw/washer dogs. At one year after surgery the recurrence rate was zero (slot) and 5/14 (screw/washer), respectively. At two years after surgery 4/14 of the slot dogs had deteriorated compared to 7/14 of the screw/washer dogs. Where investigated, the cause of deterioration was either a domino disc lesion or vertebral endplate collapse and dorsal displacement of the screw and washer.