Flashcards in Orthopaedics Deck (31):
What are the signs of unilateral forelimb lameness?
Head nods down when sound limb lands
What are the signs of unilateral hindlimb lameness?
Increased excursion of gluteal region on lame side, toe-dragging (reluctant to flex hocks) + medial swinging of affected limbs
List features of lameness.
Shortened stride length of lame limb
Increased fetlock extension (dropping) on sounder limb
Sound foot may make louder noise on landing
Explain the grading of lameness
0 = sound
1 = subtle head nod/gluteal movement (not every stride?)
2 = obvious consistent head nod/gluteal movement
3 = pronounced head nod/gluteal movement
4 = horse so lame can barely trot
5 = non-weight bearing
How much does the equine hoof grow per year?
7-10mm per month
What are the aims of shoeing?
Protect hoof wall against wear + tear
Additional support on slippery surfaces
BUT: add weight so affect foot flight, restrict expansion during landing, cause problems when incorrect
What is the cause of navicular disease?
Clinical manifestation of pain from navicular bode/distal sesamoid/navicular bursa and other associated structures
Unknown aetiology, possibly:
1. VASCULAR: arteries occlude - necrosis - bone resorption
2. BIOMECHANICAL: flat foot with long toe/low heel - increased pressure between DDFT + navic bone - remodelling + inflam of navic bone - surface defects (PAIN)
What are the clinical signs of navicular disease?
frequent stumbles, reluctant to work on circle, toe pointing @ rest, bilat. lameness- accentuated on hard circle
How is navicular disease diagnosed?
Nerve blocks: +ve to palmar digital, distal interphalangeal, navicular bursal
Rads: cyst lesions in medulla, medullary sclerosis, reduced corticomedullary demarcation, new bone on flexor surface
Nuclear scintigraphy: increased uptake at navicular bone
List the treatment options for navicular disease.
Medical- NSAIDS, vasodilation, steroids, tiludronate
Surgical: desmotomy of SL, decompress navicular medullary cavity, neurectomy
What are the clinical sins of hood abscesses?
Increased digital pulse, and ACUTE lameness
What are corns and how are they caused?
Bruise of sole between bars + hoof wall. Due to pressure from heel of shoe if left on too long, too short or foot imbalance.
List emergency foot presentations.
Puncture wounds of sole
Coronary band laceration
Heel bulb laceration
Hoof wall avulsion
Describe the aetiology, diagnosis and treatment of seedy toe.
Bacteria and fungi produce separation of the white line- doesn't produce any clinical signs. If advanced can can instability of pedal bone and infection of sensitive laminae.
DIAGNOSIS: hollow sound when hoof capsule percussed
TREATMENT: pare regions of abnormal horn and pack with iodine/metronidazol. Is severe - bar shoe to stabilise hoof
What are keratomas?
Benign hyperplastic keratin masses originating from epidermal keratin-producing cells at any point in wall/sole causing space-occupying tumours which disrupt hoof architecture allowing bacterial infection and recurrent abscesses.
What is the causative agent of thrush?
Fusobacterium necrophorum - infects frog in wet conditions
What ate the clinical signs of thrush?
Black sticky discharge
What is septic pedal osteitis?
Penetrating injury to the sole involving P3- causes cjrpnic sub-solar abscesses.
What is canker?
Chronic proliferative pododermatitis of the frog- may extend to undermine sole and heels.
What is quittor?
'Collateral cartilage infection'
How are wounds debrided?
Hydrodynamic lavage with isotonic fluid or dilute iodine/chlorhexidine or a sharp blade.
List potential wound complications.
Hypergranulation ('proud flesh')
Hoof wall/coronary band wounds
Describe the predilection sites for proud flesh.
Distal limbs and over joints (where increased skin movement and reduced vascularity), horses > ponies
What is a sequestrum?
Dead fragment of bone associated with infection- resulting in 'involucrum'- surrounding reactive bone and constant recurrent discharge from the tract.
Which scenarios indicate a hopeless prognosis for an equine fracture?
Complete fracture of radius/humerus if horse >300kg
Complete fracture of femur/tibia in adults
Long bone fractures with severe soft tissue injuries
Severely contaminated fractures
How should a horse with a suspected fracture be transported?
Forelimb fracture - facing backwards (wt on hindlimbs during braking)
Hindlimb fracture - facing forwards (wt on forelimbs during braking)
What is the cause of orthopaedic infections?
Direct contamination (penetrating wound)
Idiopathic inoculation (intra-articular injury/medication)
NEONATES: haematogenous spread
What are the common causative agents of orthopaedic infections?
Gram +ve organisms e.g. S. aureus
How are orthopaedic infections diagnosed?
Clinical exam- synovial distension
Synovial fluid leaking from joint
Synovial fluid analysis
How are orthopaedic infections treated?
Synovial lavage: large volumes- 5-30ml, arthoscopy
Systemic antimicrobials: gentamicin + penicillin
Regional limb perfusion: apply tourniquet, IV a/bs, repeat every 2 days
A/b impregnated sponges