Equine lameness and orthopaedics Flashcards
history questions
- signalment
- use
- duration of ownership
- recent management (work, feed, shoeing, housing
- previous medical problems
specific history
- limb affected
- timing and nature of onset of signs
- associated events or incidents
- details of any swelling, heat, pain
- progression of signs
- treatments employed
aims of a lameness workup
- identify limb affected
- score severity
- identify source/cause
- implement training plan
steps of a lameness work up
- physical exam
- gait evaluation
- flexion tests
gait evaluation
- different surfaces (soft/hard)
- start with walk
- trot in line
- lunge
forelimb lameness
head goes up as lame limb hits ground
hindlimb lameness
hindquarters raised by sound limb and sink during stance phase of lame limb
provocative (flexion) test
- limb flexed for 1 min
- horse trotted away as soon as limb released
- only flex the joint being assessed
limitation of flexion test
- lack of specificity to site
- inconsistency
- false positives and negatives
lunging
usually exacerbates lameness on inside leg
nerve block
- perineural, intrasynovial or local infiltration of local anaesthetic
nerve block steps
- start distally and work up
- clean area with chlorhex/spirit
- leave for 10 mins then trot up
sites of nerve block injection
- palmar/plantar digital (medial and lateral)
- abaxial sesamoid (site of digital pulse)
- low 4 point (medial and lateral)
joint blocks
- intrasynovial admin
- sterility a must
- evaluate at 10mins and then later
diagnostic imaging of lameness
- performed once a narrow area source of lameness identified
- allows interpretation of significance of findings
ultrasound for lameness
- distinguishes tendon/ligament injury from peritendinous swelling
signs signalling injury in ultrasound for lameness
- increase in tendon/ligament size
- change in internal architecture
- indistinct margination
diagnostic arthroscopy
- direct visualisation of joint cavities
- articular cartilage, synovial membrane, intra-articular ligaments, menisci
limitations of diagnostic arthroscopy
- need GA
- inability to examine most joints in their entirety
CT and MRI for lameness
- allows bone and soft tissue visualisation
nuclear scintigraphy (bone scan)
- injected IV
- taken up into bone mineral lattice
- emits gamma radiation
lesions detected by nuclear scintigraphy
- stress fractures
- arthropathies
- enthesiopathies
nuclear scintigraphy steps
- lunge to increase uptake if poss
- IV catheter placed
- horse radioactive after (isolation)
- urine collected during image acquisition
synovial sepsis
- bacterial contamination of synovial structure
- wounds in adults
- causes septic arthritis and chronic lameness if not treated
synovial sepsis investigation
- synoviocentesis and analysis
- may inject sterile saline into joint to check for egress
- contrast radiography
arthrocentesis
- sterility a must
- sedation
roles of nurse in arthrocentesis
- prep site
- non-sterile assistant
- equipment and spares ready
arthrocentesis samples
analysis:
- cytology
- protein conc
- lactate
laminitis definition
- inflammation of laminae/lamellae in hoof
- dermal/epidermal separation
- can lead to rotation or sinking of p3
phases of laminitis
- developmental= before onset of clin signs
- acute= onset of clin signs
- can become chronic or subacute - subacute= 2-3 months repair
- chronic= structural failure
clinical signs of laminitis
- stilted, pottery gait
- bounding digital pulses
- leaning back on heels
- recumbency
- worse on hard ground (increased pressure)
- struggle to turn
- reluctance to pick up feet
causes of laminitis
- endocrinopathies (PPID= cushings, EMS= eq metabolic syndrome)
- excessive carbs
- excessive weightbearing
- endotoxaemia/SIRS
- corticosteroids?
- potentially multiple mechanisms
endocrinopathic laminitis
- most cases
- majority of pasture associated cases
- pituitary pars intermedia dysfunction
- equine metabolic syndrome
risk factors of laminitis
- history of laminitis
- obesity
- endocrinopathies (insulin resistance, PPID, EMS)
- season (spring + frost)
management of developmental phase
- Cold therapy
- NSAIDs to reduce swelling
- frog supports, deep shavings bed
- treat underlying disease
management of acute phase
- strict box rest, deep shavings
- frog supports
- NSAIDs
- treat underlying cause
management of subacute laminitis
- gradually withdraw treatment
- strict box rest
subacute and chronic: - radiograph and farriery
- shorten toe over time, remedial shoeing
radiography for laminitis
- measure rotations and sinking
- metal marker on dorsal hoof wall
- coronary band -> dorsal hoof wall
effects of box rest
- limited exercise
- diet change
- behaviour (boredom)
- reduction in eating time (gastric ulcers)
nursing considerations for box rest
- monitor faecal output, colic signs. appetite, stress
- company
