Owner survey of tarsocrural effusion (bog spavin) in Clydesdale horses.

A postal survey of the owners of Clydesdale horses in the UK and USA was conducted to obtain information on tarsocrural effusion ('bog spavin') as an indicator of osteochondrosis from 935 horses. Additional information requested included details of how this condition was investigated and treated. The reported tarsocrural effusion incidence was 10 per cent. The majority of respondents believed the condition to be of concern to Clydesdale owners, but only a minority were aware of the implications of tarsocrural effusion, suggesting that owner education would be of benefit.

Comparison of three methods of injecting the proximal interphalangeal joint in horses.

The efficacy of three methods of injecting the equine proximal interphalangeal (pastern) joint was compared using cadaver limbs. Five veterinary students without prior experience attempted to inject an aqueous radiographic contrast medium into the joint using five limbs for each technique. The number of attempts was recorded and successful injection of the joint was confirmed by the presence of intra-articular contrast on radiographic examination. Levels of accuracy for the dorsal, dorsolateral and palmaroproximal approaches were 32, 48 and 36 per cent, respectively. There was inadvertent injection of the digital flexor tendon sheath using the palmaroproximal approach in 64 per cent of injections. The dorsolateral approach was associated with fewer needle manipulations.

Pressure distribution between the deep digital flexor tendon and the navicular bone, and the effect of raising the heels in vitro.

The objectives of this study were to topographically map pressure distribution across the palmar surface of the navicular bone in response to forces applied by the deep digital flexor tendon (DDFT), and evaluate the effect of raising the heels in vitro . A rig was constructed to hold an equine cadaver limb and apply controlled pressure to the navicular bone from the DDFT. Pressure-sensitive paper was used to quantify and map the resultant pressure. Changes in response to heel wedges (5 degrees and 10 degrees ) were recorded. The areas subject to maximum pressure from the DDFT were: the central ridge, the paired symmetrical areas adjacent to the ridge and the distal edge of the palmar bone surface. These regions correspond to the known sites of navicular pathology. Heel wedges redistributed the pressure exerted on the palmar surface of the navicular bone, with measurements varying depending on fetlock angle and wedge angle. These in vitro results support the hypothesis that inappropriate forces exerted via the DDFT on the bone cause navicular disease. However, they throw doubt on the practice of shoeing such horses with heel wedges as the redistribution of pressure may increase the force exerted on regions predisposed to disease.

Intra- and interobserver agreement in the interpretation of navicular bones on radiographs and computed tomography scans.

REASONS FOR PERFORMING STUDY: Criteria for the radiographic evaluation of navicular bones in horses have been published to standardise classification of radiographic signs. However, intra- and interobserver agreement have not been established. OBJECTIVE: To determine intra- and interobserver agreement in the evaluation of radiographic and computed tomographic (CT) navicular changes. It was hypothesised that: 1) intraobserver agreement would be better than interobserver agreement; 2) agreement would be better for CT than for radiography; and 3) pathological changes would be recognised with greater certainty with CT. METHODS: Radiographs and CT scans of 60 cadaver navicular bones were evaluated by 3 observers using published criteria. A subset of 30 studies was evaluated twice by one observer. Agreement was tested using the kappa statistic. Certainty about pathological changes was evaluated by giving the observers the option to choose 'not sure'. RESULTS: Agreement varied from poor to almost perfect for radiographic evaluation and from poor to substantial for CT evaluation. For radiographic evaluation mean interobserver agreement was fair, as it was for CT evaluation. For radiographic evaluation mean intraobserver agreement was moderate as it was for CT evaluation. Pathological changes were evaluated with greater certainty on CT scans compared to radiographs; however, this was not associated with improved agreement. CONCLUSIONS: Variations in classification of navicular lesions in radiographic and CT studies were considerable between and within observers and challenge the use of such studies for diagnostic and prognostic purposes. POTENTIAL RELEVANCE: The results of this study allowed the identification of evaluation criteria with sufficient precision to be useful for navicular bone evaluation.

Cartilage oligomeric matrix protein and hyaluronan levels in synovial fluid from horses with osteoarthritis of the tarsometatarsal joint compared to a control population.

REASONS FOR PERFORMING STUDY: Quantification of cartilage oligomeric matrix protein (COMP) levels within synovial fluid from the tarsometatarsal joint has not previously been reported and an effective synovial fluid marker would allow monitoring of disease progression and treatment. OBJECTIVES: To quantify levels of COMP and hyaluronan (HA) in synovial fluid from the tarsometatarsal joint, identify differences in levels from horses with osteoarthritis (OA) of the tarsometatarsal joint compared to a control population and to correlate levels with radiographic changes in horses with OA. METHODS: Synovial fluid was collected from the tarsometatarsal joint of 25 horses without hindlimb lameness (controls) and 25 lame horses, subjected to analgesia of the joint. COMP concentrations were measured using a homologous inhibition ELISA. Immunoblots of synovial fluid from 3 lame horses and 3 controls were performed to identify fragmentation of COMP. Hyaluronan (HA) concentration in synovial fluid was determined using a competition ELISA. Radiographs of the lame horses with OA were scored and correlated with levels of COMP and HA. RESULTS: Concentrations of COMP in OA of the tarsometatarsal joint were significantly lower than in the control samples. An additional fragment band of COMP (approximately 30 kDa) was identified on the immunoblots of the horses with OA and this fragment was not identified in controls. No significant difference was identified in the HA or HA:COMP ratio between lame and control horses. There was no correlation between levels of synovial fluid COMP and HA, and radiographic changes. CONCLUSIONS AND POTENTIAL RELEVANCE: Lowered levels of COMP in synovial fluid of tarsometatarsal joints correlates with the presence of osteoarthritis. However, a single value cannot be used to stage the disease process. Levels of HA may not be a useful marker for this disease. Decreased, rather than increased COMP levels, may reflect significant loss of cartilage in established osteoarthritis. A specific assay for the COMP fragment generated with osteoarthritis may allow the earlier detection of clinical cases.

Back problems. Radiology and scintigraphy.

Radiology and, more recently, scintigraphy are important ancillary diagnostic aids in the diagnosis of a horse with suspected back pain. Although the image quality is restricted by the size of the patient, radiographs have been used for several decades. With the introduction of modern fast-screen film systems, the quality of the images has greatly improved. These imaging techniques allow assessment of the anatomy and physiology of structures in the spine that are difficult or impossible to palpate. This article reviews the techniques and limitations of imaging the equine back, in addition to correlation imaging results and clinical findings.

[Techniques for radiation protection in the radiography of small animals]. / Techniken zum strahlenschutzgerechten Röntgen von Kleintieren.

Effective radiation protection demands that radiographic personnel should employ manual restraint of small animal patients only in exceptional circumstances. This publication describes methods and aids for restraint of small animals for some of the most frequently used projections. Suggestions for suitable sedation are also given.

Resection of the distal interphalangeal joint in cattle: an alternative to amputation.

A technique for the resection of the distal interphalangeal joint of cattle with infectious arthritis of the joint is described. The procedure has advantages over amputation of the digit because a weight-bearing claw is retained so that the animal can move on slatted floors and at pasture, and its productive life can be extended.