Examination of the lame animal Flashcards
Signalment clues
Breed e.g.
- lab for elbow dysplasia
- WHWT for cruciate dz
Age e.g.
- OA in the older animal
- panosteitis in the younger animal
- cruciate dz in the young and middle age
Hx clues
Onset
- chronic and progressive: OA and degenerative cruciate dz
- acute: trauma, infection, FB
- acute on chronic: cruciate rupture on patella subluxation. pathological fracture resulting from bone neoplasia
Activity
- exercise tolerance and general level of activity (cats)
- ability to jump (cats)
- reluctance to negotiate stairs
Clinical exam - protocol/steps
- observation in the consulting room (hard w cats)
- dogs walked outside
- full CE
- lameness exam
- neurological exam
Consulting room observation - points
- observe stance, particularly off loading and paw pressure in the dog
- may hold limb from ground
- head carriage (cervical disc with root signature?)
- hyperextension of the carpus or tarsus?
- able to fix the stifle?
- attentive and interested or depressed? (e.g. polyarthritis cases are often unwell)
- any obvious muscle atrophy?
- lameness of neurological deficits?
- single limb or multiple?
Lameness examination points (dog)
- observation at walk and brisk trot before CE
- head nod for forelimb (animal is lame on opposite limb)
- hip rise (pelvic lift or hip hike) and reduced stride length for hind limb (the animal is lame on this limb)
- neurological deficits
— catches nails on ground
— turn in tight circle to exaggerate the deficits - flex the limb and set off, occasionally useful in dogs as well as horses
Lameness examination points (cat)
- observe in consulting room
- encourage movement with treats and open basket
- sometimes placing the cat facing a corner will encourage it to turn around and walk away from this area
- ask O if they have or can get a video
- cats are difficult to examine on the consulting room table, they rarely show consistent pain on manipulation of their limbs and are reluctant to tolerate such manipulations
- it is better to minimise handling and restraint when examining a cat for lameness
General clinical exam points
- important to determine if there are any signs of systemic illness
- pyrexic: if a young dog possible metaphyseal osteopathy or panosteitis, any age could be polyarthritis
- resp signs: pulmonary osteopathy?
- urinary tract dz: association with lumbosacral disco-spondylitis and resulting lameness
- prostatic dz: mets spread to long bones
- systemic lupus erythematosis (SLE)
Lameness examination - main points
- limb palpation
- foot and pads
- joints
- ligaments and tendons
- patella instability
- cruciate rupture
- bones
Lameness exam - palpate the limb
- start at the bottom and work up
- muscle atrophy: particularly seen in scapula muscles and shoulder lameness
- neurogenic atrophy: marked, rapid and follows the pattern of innervation e.g. radial nerve paralysis will affect the extensors of the carpus
- any obvious swellings e.g. axillary mass with nerve root tumour
Lameness exam - foot & pads
- palpate digits and pads individually
- twists each nail
- any wear to nails suggestive of neuropathy
- examine nail beds (site of pulmonary adenocarcinoma mets in the cat)
- any generalised swelling? cat bite cellulitis is probs the most common cause of feline lameness
Lameness exam - joints
- palpate for effusions, esp the stifle (the edges of the patella tendon become less obvious with an effusion)
- painful?
- medial buttress to stifle? (suggests cruciate)
- instability e.g. cruciate
- abnormal movement e.g. inter-tarsal subluxation, carpal hyperextension
Lameness exam - ligaments & tendons
- palpate for swelling
- pain
- heat
- resulting instability if ruptured
- unstable in their respective grooves/trochleas e.g. superficial digital flexor or long digital extensor
Lameness exam - patella instability
- may subluxate medially or laterally
- often need to flex and extend with pressure on patella to bring about subluxation
Lameness exam - cruciate rupture
Cranial drawer
- in many dogs can be done conscious
- standing or lying
- if lying may panic (can requires sedation or GA)
Tibial thrust
- easier to perform if the joint is painful
- requires practice and can require sedation or GA
Lameness exam - bones
- observe e.g. the bone will look wider as if steamrolled if the dog has pulmonary osteopathy
- palpate
- squeeze: dogs suffering from panosteitis will resent this
- pain on gentle palpation e.g. neoplasia
Neurological exam
- perform if any suggestion of neurological disease
- likely to be spinal lesion
- neck or thoracolumbar pain?
- palpate axilla
- rectal exam in hind limb neuro deficits
- check anal and rectal tone
Further exams
- radiographs
- arthrocentesis
- bloods (serology)
- advanced imaging
- arthroscopy
- biopsy
- nerve condition studies
- electromyography (EMG)
Radiographic exam
- mainstay of further investigations
- good quality orthogonal views
- contrast studies: used infrequently due to increased availability of advanced imaging including US to investigate suspected FB
- examine for primary & secondary dz e.g. its hard to see a fragmented coronoid process but early arthritic changes in a young lab should raise suspicions
- with polyarthritis it is important to distinguish between erosive and non-erosive forms
Arthrodesis
- single joint: if only 1 joint is swollen: OA or septic arthritis
- multiple joints if polyarthritis suspected
- examine in house
– DiffQuick
– many neutrophils is suggestive of sepsis or if in several joints a polyarthritis
– tap 4, all from the same side unless clearly some joints are more swollen than others
Blood tests - serology examples
- RF (rheumatoid factor) for rheumatoid arthritis
- ANA/ANF (anti-nuclear antibody/factor) for systemic lupus erythematosis
- borrelia burgdorferi serology or PCR of joint fluid for Lymes dz
- Brucella canis serology or PCR of joint fluid for polyarthritis or discospondylitis
- toxoplasmosis and neospora serology is signs suggestive of neurological disease
Advanced imaging
CT
- particularly useful for elbows when can clearly see FCP or for a humeral intracondylar fissure
- also mineralisation of the infra and supraspinatus tendons
MRI
- better soft tissue definition and good for stifles, shoulders and the detection of FB
- also to examine spine for nerve root tumours and lumbosacral dz
US
- used occasionally, e.g. bicipital, Achilles/gastroc, patella and flexor tendons
- also can be useful for detection of FB
Arthroscopy
- shoulder, elbow, stifle
- difficult to gain access to carpus and talocrural joint
- can be both diagnostic and used to treat e.g. FCP
- equipment v expensive
Biopsy
Any mass or swellings
- to biopsy a possible bone tumour use a Jamshidi needle and take from centre of mass
Muscle biopsies e.g. lab myopathy
- need special handling
- send to Royal Dick School of Veterinary studies Easter Bush Pathology
What if you find nothing?
- warm client of this possibility at the outset
- emphasise what has been ruled out
