Imaging of the Equine Foot Flashcards
What are some non-imaging techniques to examine the foot?
Inspection of the hoof wall and sole
Palpation at the coronary band
Hoof testers and percussion
Diagnostic analgesia
What are the indications for diagnostic imaging of the foot?
Lameness localised to the foot
Penetrating wounds
Pre-purchase examination
Farriery management
What is the process of preparing the foot for diagnostic imaging?
Brushing/washing dirt off, removal of loose horn, removal of stones/dirt from frog sulci, placement of marker on dorsal hoof wall aligned with coronet, remove shoe if it is likely to obscure region of interest
What can be used to pack the foot to remove the outline of the foot?
Play-doh
What are some routine views in radiography of the hoof?
Latero-medial, Dorso - 60 degree - proximal palmarodistal oblique (upright pedal), Dorso - 45 degree - proximal palmarodistal oblique (upright pedal), Palmaro - 45 degree - proximal palmarodistal oblique (flexor view)
What can look like fractures in the collateral cartilages?
Variations in ossifications with separate centres of ossification resembling fractures
Not normally a cause of lameness
What other variations can look pathological?
Extensor process in lateromedial projection (check other leg)
Attachment of collateral ligaments of DIP joint and articular margin in lateromedial views
What variations are seen in dorso-60-proxial palmarodistal oblique?
Crema
Attachment of collateral ligaments of the DIP joint
Difference in the shape of navicular bone
What artefacts can be seen on the palmaro-45-proximal palmarodistal oblique?
Flexor cortex can appear falsely thickened
Corticomedullary definition less well defined
Medulla increased in opacity resembling sclerosis
How can additional diagnostic information be gained from radiographs?
Mediolateral foot balance and collateral cartilages in dorso-palmar views and oblique views to highlight the wings of distal phalanx using a dorso-60-proximo-45-lateral palmarodistalmedial oblique projection
How do you perform a radiological appraisal?
Assess diagnostic quality, identify a lesion, describe each lesion by its Rontgen signs, come to a diagnostic diagnosis, recommend further investigations
What are the Rontgen signs?
Opacity, size, margination, number, shape and location
What are the radiological signs of chronic laminitis?
Dorsal hoof wall thickness >3cm in horses/>2cm in ponies indicates chronic laminitis
Remodelling and fracture of solar margin = chronic
What radiographic sign indicates poor prognosis for laminitis cases?
> 15 degree angle between dorsal hoof wall and dorsal wall phalanx is a poor prognosis
What radiographic signs indicate sinking?
Founder distance of > 13 mm indicates sinking
Horizontal lucent lines at coronet = sinking
What radiographic sign shows separation of the lamina
Lucent line in dorsal hoof wall = separation of lamina
What radiographic sign is an indication of DIP joint OA?
Osteophyte formation
What radiographic signs indicate navicular disease?
Entheseophyte formation = spurs, proximal build up, attachment of collateral ligaments, loss of corticomedullary junction
What is the only pathognomonic sign of navicular disease?
Flexor cortex erosions which are often mistaken for central cysts
What radiographic sign of navicular disease can be seen on a DPrPaDi obl?
Abnormal border synocial fossae or border fragments
What is the radiographic sign of keratoma?
Loss of bone from distal phalanx with well defined margins on DPrPaDi obl
What does pedal bone osteitis look like on a radiograph?
Moth eaten appearance of pedal bone on DPrPaDi obl
What can MRI be used for?
Diseases behind navicular syndrome
