Spinal diseases Flashcards
Outline general findings in atlanto-axial instability
Atlantoaxial Instability (Subluxation) • young dogs (<2y), Toy breeds • acute or more gradual with waxing and waning • failure of ligamentous support, usually associated with aplasia/hypoplasia of dens in Toy breeds • sometimes associated with trauma • Clinical signs • neck pain • ataxia or tetraparesis
Outline osseous wobblers
Cervical Spondylomyelopathy (Osseous-Associated)
Giant breeds; Great Danes, Mastiffs
Usually younger than 3–4 y
Usually chronic but can be acute
Deficits common; obvious ataxia and tetraparesis Pain usually mild; seen in 50% of cases
Outline disc associated wobblers
Cervical Spondylomyelopathy (Disk-Associated)
Large dogs; Dobermans, Weimaraners
Middle-aged to old dogs
Usually chronic but can be acute
Deficits common; obvious ataxia and tetraparesis
Pain usually mild; seen in 50%–70% of cases
Outline FCEs
Breed - Any; usually large Age - Any; commonly middle-aged Acute Deficits common; usually strongly asymmetric Pain absent (after 12–24 h)
Outline SRMA
Boxers, beagles, Berneses, English pointers, Golden retrievers
Normally young; usually younger than 2 y
Acute or subacute
Deficits uncommon
Pain severe
Outline hemivertebra
Screw-tailed breeds, French bulldogs, others Young; usually younger than 1 y Chronic Deficits common; paraparesis and ataxia Pain rare
Outline degenerative myelopathy
Mainly large; German shepherds, Boxers, Pembroke Welsh corgis
Older than 5 y
Chronic (months)
Ataxia and paraparesis. The decreased patellar reflex is usually a manifestation of a dorsal (sensory) radiculopathy, and not a lower motor neuron sign Pain absent
How would diseases of L6-sacrum present?
These diseases may cause paraparesis with or without proprioceptive deficits but without proprioceptive ataxia because the spinal cord is not affected. Lameness is also frequently observed with asymmetric lesions in this area
Outline lumbosacral stenosis
Usually large breeds; German shepherds are overrepresented
Middle-aged to old
Chronic
Deficits (paresis) Typically mild-to-moderate; can be severe in late stages; lameness may be the only sign
Pain often present, but may only be elicited with deep spinal palpation
Outline discospondylitis
Any breed; usually large and giant breeds Any age; commonly young to middle-aged Usually acute Deficitis usually not present initially Severe pain, sometimes not localizable
What are the signs of brachial plexus avulsion?
✜ Avulsion of the cranial plexus roots (C6–C7 nerve roots) causes loss of shoulder movement and elbow flexion, although the animal can still bear weight on the limb as the extension of the elbow is spared. Cutaneous sensation may be lost in the dorsum of the paw and in the cranial and lateral antebrachium.
✜ Avulsion of the caudal plexus roots (C8–T2 nerve roots) results in carriage of the limb with the elbow and shoulder flexed, and inability to bear weight due to paralysis of the triceps brachii muscle (elbow extension). The elbow is dropped and knuckling of the carpus is marked on evaluation of the gait. Cutaneous
sensation may be lost distal to the elbow.
✜ Complete avulsion of all plexus roots (C6–T2 nerve roots) causes a flaccid limb with inability to bear weight and loss of cutaneous sensation in the entire limb.
Many cats with brachial plexus avulsion will also present with ipsilateral Horner’s syndrome and/or loss of the cutaneous trunci reflex.
How would radial nerve damage appear?
The limb may be carried off the ground with the elbow flexed if the musculocutaneous nerve is intact.
How common is IVDD in cats?
V rare
Disc extrusions causing neurological dysfunction are more common in the T10–S1 segments of the spine; in particular, the thoracolumbar junction (T13–L1) and L4–L6segment
Type 1 is more common
When is lymphosarcoma 98% likely in a spinal case?
3-4 neurolocations
cat over 10
Outline CSF analysis in SRMA
CSF analysis usually reveals a neutrophilic pleocytosis with an increased protein level. In chronic cases, mononuclear cells may be identified.
What is vertebral physitis?
occurs in skeletally immature dogs and may result in vertebral body collapse and secondary vertebral malformation
What is diskospondylitis
refers to primary infection of the cartilaginous vertebral end plates with secondary involvement of the disc.
What are the common signs of diskospondylitis?
spinal pain is a common clinical sign of this condition. Other clinical signs may include vertebral hyperaesthesia or pain, malaise (eg, lethargy and unwillingness to go for walks), severe neurological deficits (such as paraplegia), anorexia and pyrexia. Young, male, large breed dogs are overrepresented.
How do you diagnose disko?
he common radiographic signs are vertebral end plate lysis, disc space narrowing and sclerosis. Depending on the severity of the presenting clinical signs (eg, severe paresis or plegia), advanced imaging may be more appropriate in order to reach a diagnosis and assess spinal cord compression. MRI is again the imaging modality of choice as it will identify early changes that may not be seen in both radiography and CT scans
Should also do urine/ blood cultures
Outline spinal empyema
pyrexia, spinal hyperaesthesia and deficits related to spinal cord compression (either paresis or plegia). Diagnosis is based on advanced imaging, ideally MRI study of the spine, and in certain cases confirmation is achieved at surgery. CSF analysis may reveal an abnormal inflammatory cell count and increased protein level, but it is not always abnormal
Tx - medical or sx
What are the two main types of cervical spondylomyelopathy?
In general, giant breed dogs (eg, great danes, mastiffs and Bernese mountain dogs) present with degenerative changes of the articular facets and associated synovium, synovial cysts and vertebral canal stenosis in the first three years of life. Large breed dogs (eg, dobermann and dalmatian) are more likely to present with disc‐associated pathology, such as protrusion and ligament hypertrophy, later in life (ie, four to eight years old).
What are the clinical signs of cervical spondylomyelopathy?
bnormal gait is the most common clinical sign. The pelvic limbs are generally worse affected and a ‘two engine’ gait is generally described with short‐strided gait or overreaching in the thoracic limbs and marked ataxia or hypermetria in the pelvic limbs. Cervical pain, forelimb lameness and muscle atrophy can also be features
Outline hypervitaminosis A
Early signs may be pain or lameness due to nerve root compression and precede the establishment of bone. In severe cases, cervical immobilisation prevents self‐grooming and possibly prehension of food. The head may be held in a ventroflexed position and there may be scoliosis of the cervical spine and a painful reaction to its manipulation. Diagnosis can be reached based on the history, radiographic findings and determination of serum vitamin A concentration
What are the types of disc disease?
Hansen type I, where there is extrusion of nuclear disc material through the annulus fibrosus, or Hansen type II, where there is generally hypertrophy of the dorsal annulus fibrosus.
What is type 1 disc degeneration?
seen in chondrodystrophic breeds, such as dachshunds, terriers and spaniels. Pain is the most common clinical sign of cervical Hansen type I disc herniation, but muscular spasm or gait abnormalities can also be seen. Because of the high spinal cord to vertebral canal ratio, gait abnormalities tend to be seen with significant extrusion of disc material only
What is type 1 disc degeneration?
commonly seen in non‐chondrodystrophic, large breed dogs and is usually seen in the caudal cervical spine. Neck pain is not as common as with Hansen type I disc herniations, and gait abnormalities, including pelvic limb ataxia and thoracic limb lameness, are generally reported. Annular hypertrophy can be seen associated with other vertebral abnormalities and spinal instability. The most commonly affected disc spaces are C5‐C6 and C6‐C7. Lesions can be present at several sites, especially in large and giant breed dogs
Outline the vitamin D for chronic acute progressive etc
Peracute/acute
vascular
trauma/toxic
Subacute
inflammatory/infectious
degenerative (IVDD)
Chronic degenerative neoplastic anomalous inflammatory/infectious
Progressive neoplastic inflammatory/infectious degenerative anomalous
Static or improving
vascular
trauma/toxic
Outline ischaemic myelopathies
peracute, non-painful, non-progressive (can be painful in the first hour or so)
middle aged large non-condrodystrophoid breeds
usually at exercise
signs often very lateralised
fibrocartilage from nucleus pulposus embolises in
spinal cord vasculature – fibrocartilagenous
embolism (FCE)
Outline the main Ddx for VITAMIN D for spinal disease
V – ischaemic myelopathies
I – SRMA; meningomyelitis of unknown origin (MUOs);
discospondylitis; Toxoplasmosis, Neosporosis; FIP, FeLV
T – fractures and luxations; traumatic disc extrusion; AA instability
A – AA instability; Chiari-like malformation; vertebral anomalies
M
I
N – spinal/vertebral neoplasia
D – IVDD I and II; CSM; LSDS; DM
Outline a traumatic disc extrusion (ANNPE)
following traumatic events (RTA, fall from height) or just exercise
acute onset, non-painful, non-progressive
non-chondrodystrophic breeds
herniated nucleus pulposus is non-mineralised, causing mainly cord contusion with minimal compression
What is the ix/tx/px for FCEs and ANNPE
Diagnosis • radiography rules out # • myelography rules out compression • MRI to see Treatment • supportive care and physiotherapy • median time to ambulation ~2wks Prognosis • neurological score at presentation • extension of the lesion on MRI
N.B FCEs often more lateralised than ANNPE
Who gets SRMA and what causes it
- young dogs (6-18m), can happen at any age
- Beagle, Bernese, Boxer, Weimaraner, Nova Scotia duck tolling
- most common cause of neck pain in young dogs
- immune-mediated cause suggested
- high concentrations of IgA
- activated T-cells (suggesting antigenic stimulus)
- absence of identifiable infectious organisms
- remission of clinical signs with steroids
Outline SRMA symptoms/ ix/ tx/ px
Clinical signs
• lethargy and anorexia
• stiff gait and fever
• cervical rigidity and spinal hyperesthesia
Diagnosis
• neutrophilia
• CSF analysis - neutrophilic pleocytosis and ↑protein
• increased IgA in CSF and serum (not specific)
Treatment
• corticosteroids for 6-9m
• +/- other immunosuppressive drugs
Prognosis: very good although potential for relapse
Outline MUO
- usually acute, progressive, can be asymmetrical, can be painful
- often multifocal (sometimes affects brain)
- care as same breeds and often similar presentation to IVDD
- Diagnosis – CSF and imaging (MRI)
- Treatment – corticosteroids +/- other immunosuppressive drugs
Outline discospondylitis
infection of IVD and adjacent vertebrae; most
common at L7-S1 (also CT and TL junctions)
usually significant spinal pain, ~30% have systemic
signs of illness
Diagnosis:
• Imaging - radiography (2-4 weeks); MRI or CT
• narrowing of IVD space, roughening of endplates
and proliferation of adjacent bone
• Bacteriology - blood, urine, CSF, IVD
Treatment:
• antibiotics for at least 8 weeks
• NSAIDs, gabapentin, etc whilst painful
How do you diagnose # and luxations?
- Diagnosis
- careful neurological examination
- thoracic and abdominal radiographs
- survey lateral radiographs of spine
- orthogonal views essential (horizontal beam)
- care with sedation and manipulation!
- CT/MRI may be indicated
What is the 3 compartment model?
dorsal – articular processes, laminae, pedicles, spinous processes and supporting soft tissue structures
• middle – dorsal longitudinal ligament, dorsal vertebral body and dorsal annulus fibrosus
• ventral – rest of vertebral body, lateral and ventral annulus fibrosus, nucleus pulposus and ventral longitudinal ligament
If 2 or more compartments affected in a #, needs surgical stabilisation
How do you treat # or luxations?
Initial treatment
• stabilise trauma patient
• analgaesia
Conservative vs. surgical treatment
• use 3 compartment rule → if unstable surgery or splint
• decompression if fragments compressing spinal cord
• if transporting patient → splint
Prognosis
• lack of deep pain perception → < 5% (spinal cord laceration)
• severe vertebral displacement
Outline ix/tx for AA instability
- Diagnosis
- 2 lateral radiographs (normal and slightly flexed or extended) and VD - on vd may see complete lack of dens
- Treatment
- conservative splint for 6-12 weeks - ~60% success
- surgical
- high perioperative morbidity & mortality ~20%
- success rates vary from 50-90%
How can you treat chiari like malformation?
Medical treatment • Gabapentin, pregabalin • NSAIDs • omeprazole, acetazolamide, cimetidine, furosemide • amantidine • corticosteroids • opioids Surgical treatment • result in clinical improvement in ~50% • does not correct syrinx • high recurrence rate of clinical signs
Outline spinal neoplasia
• chronic onset, progressive, usually painful; mainly older patients but any age
• Extradural: primary vertebral, metastatic, lymphoma
• Intradural extramedullary: meningioma, nephroblastomas, nerve sheath, metastatic
• Intradural intramedullary: gliomas, ependymomas, metastatic
Treatment
• decompressive surgery
• radiation
• palliative
What are the types of IVDD?
Chondrodystrophic
• during 1st 2 years
• chondroid metamorphosis
• IVD dehydrates and nucleus is invaded by hyaline cartilage; nucleus can mineralise
Non chondrodystrophic
after middle age
fibroid metamorphosis
IVD dehydrated and nucleus is invaded by fibrocartilage; mineralisation less common
Outline IVDD type 1
herniation of nucleus pulposus through annular fibres and extrusion of the nuclear material into the spinal canal
mainly 3-6y chondrodystrophic and 6-8y non-chondrodystrophic breeds
peracute/acute onset, progressive
typically painful
Outline IVDD type 2
annular protrusion caused by shifting of central nuclear material, commonly associated with fibroid disc degeneration
more common in older, non-chondrodystrophic breeds
slowly progressive, chronic onset
spinal pain may or may not be present
typically less severe signs
What is wobblers?
large breed dogs
progressive ataxia, tetraparesis, sometimes pain
signs worse in the pelvic limbs (paresis, ataxia)
short stilted gait and muscle atrophy in thoracic
limbs
• protrusion of IVD (type II IVDD) • hypertrophy of ligamentum flavum and dorsal longitudinal ligament • hypertrophy of synovial membrane • stenosis of spinal canal • degenerative joint disease of facets
What are the clinical signs of degenerative lumbosacral stenosis
- reluctance to exercise, rise, jump into car, do stairs
- lameness – nerve root signature
- lumbosacral pain
- monoparesis/paraparesis
- proprioceptive deficits, reduced withdrawal reflex, muscle atrophy
- urinary and/or faecal incontinence
What occurs in degenerative LSS
- type II IVDD
- sclerosis of vertebral endplates and articular processes
- hypertrophy of ligaments
- hypertrophy of synovial membranes
- foraminal stenosis
- ventral subluxation of sacrum
How can you tx DLSS
- Conservative treament
- anti-inflammatories, gabapentin
- epidural steroids
- Surgical treatment
- dorsal laminectomy
- dorsal fusion-fixation
- foraminotomy
Often sx see relapses after
Outline degenerative myelopathy
• age of onset from 5y, ~9y
• insidious, progressive ataxia and paresis of pelvic
limbs, ultimately leading to paralysis (over 6-18m)
• typically T3-L3 myelopathy
• usually asymmetrical
• not painful
• diagnosis of exclusion; genetic test (not diagnostic)
• no therapeutical options but physiotherapy
indicated
• poor prognosis
