Disorders of the Equine Forelimb Flashcards
(43 cards)
How does prognosis associate with odds of returning to work?
- EXCELLENT = >90%
- GOOD = >75%
- FAIR = >40%
- GUARDED-POOR = <40%
- GRAVE = <10%
What is the most common location of forelimb lameness?
foot
- below carpus
- carpus
- above carpus
What are the 2 most common types of second phalangeal (short pastern) fractures? Where?
- comminutes
- chip
palmar process where the SDFT inserts = dropped fetlock
What are the 2 most common etiologies of second phalangeal fractures?
- trauma
- comminuted - twist injury from Western performances, pasture accident
How do horses present with second phalangeal fractures? What 2 treatments are recommended? What is prognosis like?
5/5 lame
- internal fixation + pastern arthrodesis
- coaptation - half-limb or transfixation pin cast
fair to good - decreases if coffin joint is involved
What are 3 possible etiologies of proximal interphalangeal joint OA?
(high ring bone / pastern joint)
- conformation
- trauma - sesamoidean ligament injury (roughened attachments)
- osteochondral cysts
What are 4 signs of proximal interphalangeal (pastern) joint OA?
- moderate lameness
- characteristic bony swelling on dorsal surface (roughened attachment)
- positive to limb flexion
- blocks to abaxial or pastern joint blocks
What are 3 options of treating pastern joint OA?
- manage OA pain and progression with IA corticosteroids
- arthrodesis with advanced cases (lag P1 and P2 together) - better prognosis HL > FL
- facilitated ankylosis with ethyl alcohol injection. -destroys articular cartilage to allow direct bony bridging
How is treatment for pastern joint OA done? What is prognosis like?
- mild to moderate = corticosteroid injection
- moderate to severe = arthrodesis or facilitated ankyloses
fair to good
What are the 3 most common etiologies of metacarpophalangeal (fetlock) joint OA?
- athletic performance
- conformation
- trauma
What are 4 signs of metacarpophalangeal )fetlock) joint OA?
- lame
- positive flexion
- effusion
- blocks to fetlock joint and low 4 point
What treatments are recommended for fetlock joint OA?
- manage OA pain and progression
- arthrodesis if severe and pasture sound only
Where are forelimb fetlock osteochondral fragments (chips) most commonly found? What are the 2 most common etiologies?
dorsal
- trauma - jumpers, racehorses
- OCD - proximal P1, mid-sagittal ridge of MC3
What are 3 signs of fetlock chips? How are they treated? What is prognosis like?
- mild to moderate lameness
- fetlock effusion
- positive to fetlock flexion
arthroscopic removal
good to excellent
What are the 2 most common etiologies of 2nd and 4th metacarpi (splint bones) exostosis?
- trauma - medial
- conformation - bench knee (off-center canon) with toe out = winging in and interference
What are 2 signs of splint bone (2nd and 4th metacarpi) exostosis? When is U/S and MRI used for diagnosis?
- swelling
- usually not lame
rule in or out suspensory ligament involvement
If this view is a DMPLO, which splint is affected?
medial structures are highlighted on plantar surface –> 2nd metacarpi exostosis
What treatment is recommended for 2nd and 4th metacarpi (splint) exostosis? What if the suspensory ligament is involved? What is prognosis like?
benign neglect - rest, NSAIDs
remove splint - segmental or en bloc ostectomy
excellent
What is the most common etiology of 3rd metacarpus (cannon bone) disease?
“bucked shins”
- dorsal MC3 periostitis common in racehorses early in training
- this remodels dorsomedial MC3, leading to saucer or cortical fractures
What are 3 signs of dorsal 3rd metacarpal disease? What 2 diagnostics are recommended?
- acutely lame with a short stride, especially after hard work (races, breezes)
- dorsal swelling
- pain on palpation
radiographs & nuclear scintigraphy
What are 5 options for treatment of dorsal 3rd metacarpal disease? What is prognosis like?
- NSAIDs
- rest - 10-14 days for mild, months for severe
- alter training
- shockwave
- osteoclast inhibitors
good to excellent
What is the most common etiology of 3rd metacarpal fractures in foals and racehorses? What immediate treatment is needed?
FOALS - pasture accident
RACEHORSES - cumulative stress
correct coaptation - need to be able to weight bear for proper healing
What are the 4 most common types of cannon bone fractures? What horses get each?
- DIAPHYSEAL - foals and adults; stepped in holes, trauma
- PALMAR PROXIMAL - Standardbreds
- DISTAL CONDYLAR - Thoroughbreds
- SALTER HARRIS TYPE II - foals (metaphysis + physis)
Diaphyseal cannon bone fracture: