1. The sign wasn’t placed there
By the Big Printer in the sky
Prof. A.V. SRINIVASAN.
Prof. A.V. SRINIVASAN.
,,
MD, DM, PhD, DSc, FRCP (Lond), FAAN, FIAN
EMERITUS PROFESSOR OF NEUROLOGY
EMERITUS PROFESSOR OF NEUROLOGY
FORMER HEAD AND PROFESSOR OF NEUROLOGY
FORMER HEAD AND PROFESSOR OF NEUROLOGY
Institute of Neurology
Chennai
Chennai

5. Pharmacology
 Physical and Neurological
Non Pharmacolgical
Affective
Behavioural
Cognitive
Social

6. Strategies - to be incorporated into a
non-pharmacologic approach.
 Education about condition
 Patient preference
 Modification of sensory aspects of pain
 Modification of cognitive/emotional
aspects of pain
 Built-in assessment and reassessment

7. Non-pharmacological therapies
Simple Physical Cognitive
Individual
Pacing Movement
work
Goal-setting Manipulation Group work
Relaxational Interventional

8. Non-pharmacological therapies
Physical Treatments
Movement-
Simple based Interventional
Spinal
Ice/Heat Manipulation Peripheral Central
Splinting Physiotherapy Acupuncture Injections Stimulation
Corset/support Exercise TENS “Pulsing” Psychosurgery
Injections Neurolysis
Cryotherapy Stimulation

9. Cognitive Treatments
Individual Group
Counseling Pain Management
Programs
Transpersonal Recovery Model
therapy (peer-to-peer)
CBT/CAT/ACT
Peer Support
Hypnosis

10. Modification of the sensory
aspects of pain
 Simple measures - heat, ice, massage, manipulative
therapies (e.g. chiropractic, osteopathy), physiotherapy
 Treating the primary cause - e.g. improve diabetic
control; supplement thiamine; reduce/stop alcohol
consumption. Treating the primary cause includes
interventional techniques such as surgery for disc prolapses
or spinal stenosis; or nerve translocation surgery (e.g.
carpal tunnel release)

11. Modification of the sensory
aspects of pain
 Stimulating inhibitory mechanisms in the periphery or
in the spinal cord: e.g. acupuncture /TENS; electrical
peripheral nerve or dorsal column or central (deep-brain)
stimulation
 Inhibition or prevention of ascending nerve
transmission in the peripheral nervous system, in the
dorsal root ganglion or spinal cord: e.g. nerve blocks,
neurolysis or rhyzolysis

12. Modification of the sensory
aspects of pain
 Alter pain processing at the cortical level ,
e.g. cognitive therapies, biofeedback, hypnosis,
meditation. It is currently unclear the exact way in
which these therapies alter sensation, but is
assumed to involved both descending inhibition
and alteration of sensitivity to ascending stimulus

13. Neurogenic Pain
 copious documentation (I have a list
here…)
 fixed ideas (“I have been told I have a
crumbling spine”)
 frustration (“I just want it sorted!”)
 hopelessness/helplessness (“you won’t be
able to help me, no one can”)

14. Thomas Elbert
Basic
Principles
Cortical representation expands linearly with use.
 Synchronous inputs lead to fusion of cortical zones
 Asynchronous inputs lead to segregation of cortical
zones.
Disuse or De-afferentation leads to invasion of
unused cortical area by nearby neurons.

15. Sensory modulation in spatial neglect
Novel Techniques
 Peripheral somatosensory- Magnetic
stimulation
 Repetitive optokinetic stimulation
 Neck Vibration training
Drug Treatment is currently unsuccessful

16. Sensory modulation and Stroke
 Rehabilitation aimed to increase use of
paretic hand
 Virtual reality
 Motor imagery
 Prof. V.S..Ramachandran’s virtual reality box
 Phantom limb phenomenon

17. Other techniques
 Caloric tests for balance
 Brings awareness of illness to patient.
 Kinesthetic, visual, and auditory cues to
improve Parkinsonian gait.

18. INTERMANUAL REFERRAL OF
SENSATION AND EXTINCTION OF
PAIN IN PERIPHERAL AND
CENTRAL LESIONS OF SOMATO
SENSORY SYSTEM

19. BACKGROUND
 Allesthesia and extinction of referral
sensation in brachial plexus lesions
A.V. Srinivasan and V.S. Ramachandran et al (1998)
 Intermanual referral of sensations after
central lesions of the somato sensory
system
K. Sathian et al (2000)

20. METHODS
8 patients (19-51 years)
 Brachial plexus lesion – one
 Amputation – two
 Stroke – five
 Patients were video filmed in the movement
disorder clinic. Pinprick, cold, vibration and
kinesthesis were tested
 MRI & ENMG in all cases

21. CENTRAL LESION
Stroke
Thalamic stroke - three
Temparo parietal - two
Three to four months later
Ipsilateral arm - no referral
to leg

22. STROKE Contd…
 Intense pressure on the normal hand resulted
in extinction of pain in the stroke side
 Pain returned within one
minute of the pressure
 Intense pressure improved
sensory and motor
phenomenon

23. AMPUTATION
 Both the patients (below
elbow & knee amputation)
showed intermanual referral of
sensation within 10 days. The
referred sensations of touch
and vibration lacked spatial
organization and poor
localization with a relatively
high threshold

24. CASE VIGNETTE (BRACHIAL PLEXUS
LESION)
 21 year old girl, after total
brachial plexus lesion was
examined 6 months, 1 ½ &
2 ½ years after the lesion
 She had sensations
intermanually referred in a
topographically organized
manner in the phantom limb

25. INTERMANUAL REFERAL AND EXTINCTION OF
PAIN SENSATION
Hemiparesis with Brachial
hemisensory deficit Amputation plexus
Spatial organi- Poor Poor Excellent
sation
Localisation Good Poor Excellent
Time of occurance After 3 to 4 months Immediate Immediate
with in 7 days with in 7days
Pain After a delay of Immediate Immediate
Extinction 3 - 5 seconds

26. DISCUSSION
Anatomical facts
1. Primary somato sensory area 3b
2. A. Primary somato sensory area 1 & 2
2. B. Second somato sensory cortex and
parietal operculum
In 2a & 2b the receptive fields are larger
bilateral and callosal connection are
abundant

27. DISCUSSION Contd…
 Contralateral referral of sensations was not
found in normal subjects or in hemiparetic
patients without hemi sensory loss
 Neural mechanisms for perceptual alteration
not clear

28. DISCUSSION Contd…
It appears that a decrease in
somatosensory input to one
cerebral hemisphere from the
contralateral hand allows
responsiveness of neurons in
this hemisphere to
moderately intense tactile
stimuli on the ipsilateral hand
to exceed perceptual
threshold (which does not
normally occur).

29. CONCLUSION
 Intermanual referral & extinction of pain
occurred immediately in amputation and
brachial plexus lesions and after a delay in
stroke
 Intermanual referral of sensation occurred
topographicaly organised manner in brachial
plexus lesions but not in amputation and stroke

30. READ not to contradict or confute
Nor to Believe and Take for Granted
but TO WEIGH AND CONSIDER
THANK
YOU

31. CASE VIGNETTE (BRACHIAL PLEXUS
LESION)
 21 year old girl, after total
brachial plexus lesion was
examined 6 months, 1 ½ &
2 ½ years after the lesion
 She had sensations
intermanually referred in a
topographically organized
manner in the phantom limb

32. INTERMANUAL REFERAL AND EXTINCTION OF
PAIN SENSATION
Hemiparesis with Brachial
hemisensory deficit Amputation plexus
Spatial organi- Poor Poor Excellent
sation
Localisation Good Poor Excellent
Time of occurance After 3 to 4 months Immediate Immediate
with in 7 days with in 7days
Pain After a delay of Immediate Immediate
Extinction 3 - 5 seconds