Bilateral Spastic Paraparesis (inc HSP and transverse myelitis)

Question 1

Examination dance for bilateral UMN spastic paraparesis

Answer 1

Inspection
1. Chronicity: wasting (LMNL) vs contracture (UMNL) or both
- Wasting is often not a feature of UMNL, however in longstanding cases there will be disuse atrophy wasting
- Contracture in chronic immobility
2. Mobility
- Wheelchair immobility
- Walking aid with scissors gait
(or rarely high steppage gait in foot drop)
3. Surgical scars
- Spinal level
- Deformity correction over ankle, or pes cavus
4. IDC - bladder involvement

Examination
1. Bilateral pyramidal weakness
- flexors: hip flexion, knee flexion, ankle dorsiflexion, eversion
2. Hypertonia - foot jump off from couch
(Look for hypotonia LMNL signs below UMNL level)
3. Hyperreflexia and crossed adductor response (pyramidal lesion)
- Opposite adductors contract during knee jerk
(Look for hyporeflexia LMNL signs below UMNL level)
4. Ankle clonus > 3 beats
5. Extensor plantar response on Babinski
5A. Oppenheim sign: extensor plantar response on pressing inner border of tibia
5B. Gordon sign: extensor plantar response on pinching Archilles tendon
6. Is there a sensation loss?
- Patchy: cervical myelopathy
- Peripheral neuropathy: FA, SCA, cervical myelopathy, multiple sclerosis
- DCML: tabes dorsalis (neurosyphilis)
- Pinprick in cape distribution: syringomyelia
- Sensory level: transverse myelitis, spinal cord lesion tumour/compression/trauma
7. Is there ataxia on heel shin test/dysdiadochokinesia?

No sensory loss
- Hereditary spastic paraparesis (10% may have sensory loss)
- Cervical myelopathy (that does not affect sensation)
- Parasagittal lesion
- Bilateral cortical lesion

Wishlist
Fundoscopy

Question 2

Approach to spastic paraparesis (bilateral UMN)

Answer 2

Differentiating features
1. Mixed lesion - LMNL below UMNL level
2. Cerebellar signs
3. Sensation impairment

Question 3

Sensory level in bilateral spastic paraparesis

Answer 3

Question 4

What is spasticity?

What is rigidity?

Answer 4

Spasticity
- Increase in muscle tone due to hyperexcitability of stretch reflexes, velocity-dependent increase in tonic stretch reflex
- More marked at onset of movement, decreasing as passive movement continued (clasp knife phenomenon)

Rigidity
- Constant increased tone throughout range of motion independent of velocity

Question 5

Pathophysiological basis for spasticity

Answer 5

Enhanced stretch reflex activity
- Increased muscle tone (tonic stretch reflexes)
- Exaggerated reflexes (phasic stretch reflexes)

Normal:
Turning off stretch reflexes to allow normal movement
Brain sends inhibitory inputs from reticulospinal and other descending pathways to motor neurons

UMNL
Loss of inhibitory inputs from spinal cord
Alpha motor neurone hyperexcitability
Denervation supersensivity, shortening of motor neurone dendrites, sprouting of dorsal root afferents

Question 6

Hereditary spastic paraparesis
(paresis - limited movement; plegia - complete inability)

Answer 6

Also known as
Familial spastic paraparesis
Stumpell-Lorrain syndrome

Definition
Progressive severe spasticity of lower limb due to degeneration of ends of corticospinal tracts within spinal cord
- X-linked, AD (most common) or AR
- Ends of longest corticospinal fibres affected

Clinical features
1. Spastic weakness - LL greatly affected than UL
2. Muscle wasting in very chronic > 10 years distal muscle group - small muscles of feet and tibialis anterior
3. Peripheral nerves normal
4. +/- Sensory impairment in 10-65% patients
5. +/- Diminished proprioception and vibration (central axonopathy)
6. Pes cavus

Complications
1. Cataracts or optic nerve atrophy/retinopathy
2. Ataxia - lack of coordination
3. Epilepsy
4. Cognitive impairment
5. Deafness
6. Bladder and urinary incontinence
7. Respiratory muscle weakness
8. Peripheral neuropathy (rarely)

Question 7

Tropical spastic paraparesis

Answer 7

Definition
HTLV-1 associated myelopathy
Characterised by chronic progressive spastic paraparesis
Incubation months to years

Features
1. Progressive spastic weakness, proximal > distal
2. Sphincter disturbance
3. Mild sensory involvement

Epidemiology
Caribbean, Africa, Japan, South America

Mode of transmission
1. Sexual contact
2. Sharing of needles, blood products
3. Vertical transmission

1-4% develop

Question 8

Transverse myelitis

Answer 8

Definition
Acute inflammation of cord, affecting diffusely at 1 or more levels, affecting all spinal cord function
- Resultant PAIN, bilateral motor, sensory and sphincter deficit below level of lesion
- Progresses rapidly within hours to days

Causes:
1. Bacteria - lyme, mycoplasma, tuberculosis, syphilis
2. Viral - HSV, VZV, CMV, EBV, HIV, HAV, influenza, echovirus
3. Demyelination (MS, Devic’s disease)
4. Radiation myelopathy
5. Anterior spinal artery occlusion
6. Vasculitis
7. Autoimmune
8. Vaccination

Treatment: corticosteroid

Question 9

Investigations for bilateral spastic paraparesis

Answer 9

1. Relevant blood tests
   - Full blood count - anaemia, infection
   - B12 and folate - SCD
2. Imaging - magnetic resonance imaging of brain and spinal cord
3. Lumbar puncture - if suspecting multiple sclerosis, transverse myelitis
4. Nerve conduction studies and electromyography
5. Genetic testing and counseling

Question 10

Management of spasticity

Answer 10

Non-pharmacological
1. Physiotherapy - stretching, strengthening
2. OT - orthoses, casts, braces
3. Cold packs
4. Electrical stimulation

Pharmacotherapy: for spasticity and neuropathic pain
1. Benzodiazepines
2. Baclofen
3. Tizanidine
4. Dantrolene
5. Clonidine
6.Gabapentin
7. Intrathecal - baclofen, phenol
8. Botulinum toxin injection

Neurosurgery
- selective dorsal rhizotomy (between L2 and S2)

Orthopaedics
- Contracture release
- Tendon transfer
- Osteotomy