Title: Neurological Complications following SCI William McKinley MD Director, SCI Rehabilitation Medicine Associate Professor PM
1Neurological Complications following SCIWilliam
McKinley MDDirector, SCI Rehabilitation Medicine
Associate Professor PMRVCU / MCV
2Overview of Spinal Cord Function / Injury
- Movement (Weakness)
- Sensation (Sensory loss, Pain)
- Muscle tone (Spasticity)
- Bladder/bowel (Neurogenic B/B)
- Sexuality (Sexual dysfunction)
3Neurological Complications Following SCI
- Syringomyelia
- Pain
- Spasticity
4Syringomyelia
- Syrinx fluid filled cavity (cyst) within the
spinal cord - Syringomyelia neurological symptoms due to
syrinx - incidence - 3-10
- etiology - trauma, tumor, congenital
- area of tissue damage / inflammation
- can expand, elongate, cause pressure
5Syringomyelia symptoms
- Pain (radicular)
- Sensory loss
- weakness
- Spasticity
- Hyperhydrosis
- Bladder / bowel
6Syringomyelia Diagnosis / Treatment
- Dx
- clinical findings / suspicion, physical exam
- MRI (CT/myelogram, U/S)
- Rx
- surgical shunt / drainage to low pressure
points - syrigopleural, syringoperitoneal)
- pain management
7SCI PAIN
- Challenging issue
- Physiologically psychologically
- Incidence 15 - 85
- Etiology
- Spinal cord pain
- Radicular
- Muscuoskelletal
8Factors associated with SCI Pain
- Level of Injury (LOI)
- Complete vs Incomplete
- Time since injury
- Type of injury (GSW, trauma)
- Psychological factors
9Classification of SCI PAIN
- Central Pain
- Central Pain - below LOI, symmetrical (burning,
tingling) - Radicular Pain
- At the LOI, asymmetrical (aching, stabbing)
- Musculoskelletal Pain
- localized MS structures (aching, tender)
10Mechanism of Neurogenic SCI Pain
- largely unknown
- Irritation / abnormal firing of damaged nerve
axons or roots - Loss of descending inhibition
11management of SCI Pain
- Pharmacological - neuropathic pain meds
- Surgery
- Adjunctive treatments
- Psychological Rx
12Neuropathic meds
- Anticonvulsants (nerve membrane stabilization)
- Neurontin, Tegretol, Dilantin
- Antidepressants (increase Seritonin levels)
- Elavil, Trazadone
- Others Mexiletine
- Epidural agents
- Morphine, Clonidine, baclofen
13Non-pharmacologic Rx
- Spinal cord stimulation
- ? effectiveness
- Surface TENS
- best with radicular pain incomplete injuries
- Surgery
- Dorsal Root Entry Zone (DREZ)
14Spasticity
- Definition Abnormal, velocity-dependent
increase in resistance to passive movement of
peripheral joints due to increased muscle
activity
15Spasticity Etiology (Diagnosis)
- Spinal Cord Injury
- Traumatic Brain Injury
- Stroke
- Multiple Sclerosis
- Cerebral Palsy
16Pathophysiology
- Intrinsic hyperexcitability of alpha motor
neurons within the spinal cord secondary to
damage to descending pathways - cortico, vestibulo, reticulospinal
- CNS modification
- neuronal sprouting
- denervation hypersensitivity
17Symptoms of Spasticity
- NEGATIVE SXs
- Weakness
- Function
- Sleep
- Pain
- Skin, hygiene
- Social, Sexuality
- contractures
- USEFUL SXs
- Stability
- Function
- Circulation
- Muscle bulk
18Spasticity Treatment Decisions
- Is Spasticity
- Preventing function?, Painful?
- A result of underlying treatable stimulus
- A set-up for further complications?
- What Rx has been tried?
- Limitations and SEs of Rx
- Therapeutic goals
19Goals of Therapy
- Ease function (ambulation, ADL)
- Decrease Pain, contracture
- Facilitate ROM, hygiene
20Spasticity Scales
- Ashworth Scale
- 1 no increased tone
- 2 slight catch in ROM
- 3 moderate tone, easy ROM
- 4 marked tone, difficult ROM
- 5 Rigid in flexion or extension
- Spasm Frequency Scale
- 0 none
- 1 mild
- 2 infrequent
- 3gt 1 per hour
- 4 gt 10 per hour
21Rehab Evaluation (cont)
- Gait patterns
- Transfer abilities
- Resting positioning
- Balance
- Endurance
22Management Options
- Physical interventions
- systemic medications
- chemical denervation
- Intrathecal agents
- orthopedic interventions
- neurosurgical interventions
23Rehabilitation Interventions
- Positioning (bed, wheelchair)
- Modalities
- heat (relaxation)
- cold (inhibition)
- Therapeutic Exercise
- inhibitory to spastic muscles
- facilatory to opposing muscles
- Orthotics
24Non-Conservative Treatment Options
- Oral Medications
- Injections (Phenol , Botox)
- ITB (Intra-Thecal Baclofen)
- Surgical (nerve, root, SC)
- Spinal Cord Stimulator
25Oral Antispasticity Medications
- Baclofen
- Dantrium
- Diazepam
- Clonidine
- Tizanidine
- (limitations non-selective, side effects)
26Baclofen (Lioresal)
- GABA-B analogue binds to receptors
- inhibits release of excitatory neurotransmitters
(spasticity control) - Ca (pre-synaptic inhibition)
- K (post-synaptic inhibition)
- may also decrease release of substance P (pain
control)
27Dantrium
- Inhibits Ca release at muscle level
- Preferred TBI, CVA, CP
- SEs - weakness, GI
- Hepatotoxicity (lt1)
28Diazepam
- GABA potentiation
- Usage SCI, MS
- SEs - CNS depression, dependence,
29Clonidine
- Alpha-2 receptor blockage
- Usage SCI
- Max dose - .4mg/d (oral patch)
- SEs - OH, syncope, drowsiness
30Tizanidine (Zanaflex)
- 1996 - Approved for SCI, MS, CVA
- Alpha-2 agonist (pre-synaptic inhibition)
- 1/10 potency of Clonidine In lowering BP
- Dose T1/2 2-5hr, begin 4 mg qhs (max 36 mg)
- SEs - Sedation, nausea, LFTs
31Chemical Neurolysis
- Phenol 5-7- Motor Point/Nerve block
- Non-selective destruction of axons/myelin
- Inds Local (not general) spasticity
- Duration 3-6 months
- SEs - dysesthetic pain
32Botulinum Toxin
- 1989 FDA approved for strabismus blepherospasm
- Botox-A inhibits Ach Release at NMJ
- Dose 300-400u total (50-200/muscle)
- Onset 2-4 hours, Peak 2-4 weeks
- Duration 3-6 months
- ? Immunoresistance w/repeated injs
33Spasticity Surgical Management
- Rhizotomy (posterior)
- Cordotomy
- Tendon Release
- (limitations invasive, bowel/bladder changes,
irreversible, effectiveness varies)
34Intrathecal Baclofen and Spasticity
- Intrathecal delivery of baclofen via an
inplantable pump is a safe and effective therapy
for the management of spasticity !
35Intrathecal Baclofen
- Indicated for patients unresponsive to oral meds
or with SEs - Delivered directly to intrathecal space affording
much higher drug concentration - Implantable system allows non-invasive monitoring
adjustments
36ITB Successful Outcomes
- Study results since 1984 demonstrate reduction of
Ashworth spasticity scores and spasm scales - Other results include improvements in
- pain
- bladder function
- chronic drug side effects
- quality of life for patient caregiver
37ITB
- 1992 - FDA Approved ITB for spinal Spasticity
- 1996 - FDA Approved for Cerebral Etiologies (BI
and CP)
38ITB Pharmacokinetics
- Baclofen GABA-b agonist inhibits neuronal
firing - ITB (Lioresal)
- preservative-free stable for 90 days
- half-life 1.5 hours
- typical dose 1/100 of oral dose
- average daily dose 300-800ug
- lumbar/cervical ratio 41
39Decision to Treat w/ ITB
- Have oral antispasticity meds truly failed?
- Are their SEs too great?
- Can a single definitive surgical procedure
accomplish similar goals? - Is precise control necessary for functional
gains? - Does gain in function / comfort justify invasive
procedure maintenance?
40Other Considerations ITB
- Test dosing / trial dose via intrathecal lumbar
puncture - Pump re-programming via radio-telemetry and
computer - Maintenance follow-up Q 4-12 weeks
41THE END