VM 569 Equine Conditions of the Foot (Day 9, part 4)
How does selenium cause clinical signs in chronic selenium toxicosis? (2)
-Binds sulfur containing amino acids -Methionine and cystine
What are sidebones? What breed are the most common in? What is the clinical relevance of this?
-Bone formation of the sides of the hoof -Most common in draft horses -Little clinical relevance - cause no issues in horses with large wide feet, but can impinge on P2, coronary band, or laminar column in narrow footed horses
What are corns? What are the caused by?
-Bruise at angle bar and wall -Caused by trauma (shoes left on too long, stone between bar and shoe)
What is canker? How common is it?
-Chronic hypertrophic pododermatits of the frog and bulbs of the heel -Rare
What is the treatment of thrush? (2)
-Clean -Topical preparation - bleach, betadine, chlorine dioxide
What is the treatment of osseous cysts of the distal phalanx? (2)
-Conservative treatment -Surgical debridement of cyst
Describe dry, moist, and suppurative bruised soles. (3)
-Dry - appear as red stains -Moist - accumulation of serum -Suppurative - becomes infected (subsolar abscess)
What does chronic selenium toxicosis cause? (4)
-Dry brittle hair -Alopecia -Weight loss -Abnormal hood growth
What are the clinical signs of septic pedal osteitis (SPO)?(3)
-Front feet usually involved -Lameness -More painful that non-septic pedal osteitis - stronger digital pulse
What is the treatment of chronic laminitis as a cause of non-septic pedal osteitis (PO)? (2)
-Guarded-unfavorable prognosis for return to athletic function -Principles of hoof care and protect the sole
What are bruised soles? (3)
-Hemorrhage between corium of the sole and sole -Incorporated into deeper aspect of epidermis -Becomes visible as sole grows (1-2 weeks)
How are subsolar abscesses diagnosed? (3)
-Hoof testers -Nerve blocks -Radiographs - used to rule out other more serous problems
What are the clinical signs of a keratoma? (2)
-Lameness -Distortion of hoof wall or white line
What are the clinical signs of white line disease? (6)
-Lameness -Flat sole -Sole pain -Slow growth -Heat -Strong digital pulse
How is chronic selenium toxicosis diagnosed? (2)
-Presumptive - clinical signs -Definitive - feed, serum, or tissue analysis
What is primary and secondary non-septic pedal osteitis (PO) associated with?
-Primary - severe and chronic sole bruising -Secondary - chronic laminitis
What are potential sources of selenium that can result in chronic selenium toxicosis? (4)
-Selenium accumulator plants -Grains growth in selenium rich soil -Water (0.5-2ppm) -Iatrogenic - owners giving too much systemic supplementation
What is the treatment for puncture wounds of the coronary band? (3)
-Sepsis or involvement of synovial structures - joint lavage, appropriate antibiotics, NSAIDs -Septic osteitis - surgical debridement of infected bone -Septic chondritis - surgical debridement of necrotic cartilage and infected tissue
What are the causes of submural infections? (4)
-Wounds -Cracks -Separation -Adjacent subsolar abscesses
What is quittor?
Chronic infection resulting in necrosis of the lateral cartilage characterized by intermittent, multiple, draining tracts
What is a keratoma?
Growth made of keratin between the hoof wall and distal phalanx
What is the prognosis for puncture wounds to the frog?
Guarded
When does chronic selenium toxicosis occur?
Due to ingestion of 5-10ppm
What does successful outcome of puncture wounds of the frog require?
Early and aggressive intervention
How is septic pedal osteitis (SPO) diagnosed?
Radiographs
What is white line disease? (1)
Separation of the hoof wall at the white line
What is thrush?
Infection of the central and lateral sulcus of the frog characterized by a dark, foul smelling exudate caused by anaerobic bacteria
What is non-septic pedal osteitis (PO)?
Inflammatory response resulting in demineralization
What are the clinical signs of osseous cysts of the distal phalanx? (1)
Intermittent lameness that recurs with exercise
What are bruised soles caused by?
Trauma
What is the most likely cause of osseous cysts of the distal phalanx?
Trauma
What is the treatment for septic pedal osteitis (SPO)?
Surgical debridement
What is the treatment of quittor? (1)
Surgical excision of tracts and necrotic cartilage
What are the clinical signs of non-septic pedal osteitis (PO)? (3)
-Usually affects front feet -Lameness depends on severity -Accentuated with exercise or after trimming
Describe the appearance of white line disease. (3)
-Usually occurs from the toe to the quarter -Extends from the ground surface upward -White, odiferous, chalky
How are microbes introduced in septic pedal osteitis (SPO)? (4)
-Abscesses -Solar margin fractures -Penetrating wounds -Laminitis with prolapsed corium through the sole
What is the treatment for bruised soles? (3)
-Decrease concussion to sole -Reduce inflammation - NSAIDs, soak, and poultice -Protect sole - full pad or wide web shoe
What is the treatment for chronic selenium toxicosis? (3)
-Decreases selenium intake -Provide adequate hoof cate -Supplement diet with methionine and cystine
What does septic pedal osteitis (SPO) usually result in?
-Demineralization of distal phalanx
What are the clinical signs and diagnosis of puncture wounds of the coronary band? (4)
-Depends on the depth, location, and chronicity -Gently examine the tract with a flexible probe -Radiograph with probe in place -Obtain a synovial fluid sample
What is the treatment for submural infections? (6)
-If suspect, soak and poultice -If drainage, flush tract and provide local wound care -Establish ventral drainage -Soaking the "clean" foot -Partial hoof wall resection to debride -Persistent drainage (7-10 days) -Systemic antibiotics not needed unless evidence of infection in soft tissues or bone
What are the clinical signs associated with submural infections?(3)
-Moderate to severe pain (1-4 days) -Difficult to distinguish pain from other painful conditions until drainage occurs -May be present with unusual gait
What is the treatment for subsolar abscesses? (5)
-Need to localize and expose -If not immediately evident - soak and poultice - softens and draws out infection -Goals is to provide ventral drainage without damaging -Treat locally with antiseptic -Provide protection
How are osseous cysts of the distal phalanx diagnosed? (2)
-Nerve blocks -Radiographs
How are submural infections diagnosed? (2)
-Not made until it the abscess begins to drain or is ready to drain -May need to perform fistulogram to differentiate from other conditions
What is used to diagnose keratomas? (3)
-Partial response to palmar digital nerve block -Complete response to abaxial nerve block -Radiographs - not all will show radiographic signs, but some will shoe discrete lucent defect
What is a subsolar abscess? What is it due to? (3)
-Puncture of cornified sole -Due to punctures, cracks, and hot nails
What is quittor caused by? (4)
-Puncture wounds -Lacerations -Submural abscesses -External trauma
How is non-septic pedal osteitis (PO) diagnosed? (3)
-Radiographs - appears as focal or diffuse lucency or new bone formation -Hoof tester -Response to palmar digital nerve block
How can puncture wounds of the frog be diagnosed? (4)
-Radiography with foreign body in place -Trimming of frog to locate foreign body -Use flexible probe if foreign body has already been removed -Determine if other structures are involved
What are the clinical signs of subsolar abscesses? (1)
-Range from mild lameness to fracture lameness
What is the treatment of chronic bruised soles as a cause of non-septic pedal osteitis (PO)? (2)
-Reduce inflammation -Decrease concussion with protective shoeing
What is the treatment of corns? (2)
-Remove shoe -Pare out area
What is the treatment for white line disease? (4)
-Resect undermined wall -Debride area -Topical antispectics -Exposure to air and sunlight
What are other names for osseous cysts of the distal phalanx? (3)
-Subchondral bone cyst -Periarticular subchondral cyst -Bone cyst
What are other names for submural infections? (3)
-Submural abscesses -Ascending infection of the white line -Gravel
What is the treatment of canker? (4)
-Surgical debridement -Systemic antibiotics -Topical antimicrobials -Use dry bandage until epithelization occurs
What is the treatment for puncture wounds to the frog? (5)
-Surgical emergency -Debride, flush -Antibiotics - regional limb perfusion -NSAIDs -Protect until healed - bandage or hospital plate
What is the treatment for keratomas? (1)
-Surgical removal of the growth - approach through the hoof wall or sole
