Somatic pain comes from skin and deep tissues, while visceral pain comes from internal organs. Both types of pain are detected by nociceptors and felt differently. Somatic pain is usually easier to locate and more intense, described as musculoskeletal pain. Visceral pain feels dull, vague, and hard to pinpoint, described as constant or crampy. The gate control theory proposes that stimulation of large diameter fibers can inhibit pain transmission through the substantia gelatinosa in the spinal cord. Various pain modulation techniques like TENS work through this mechanism.

1. PRESENTED BY: DR.SHILPA PRAJAPATI (1st YEAR MPT)

2.  An unpleasant sensory and
emotional experience associated
with actual or potential tissue
damage, or described in term of
such damage.
-International Association For the Study of pain

3. NOCICEPTIVE NEUROPATHIC
Somatic Visceral
• bones, joints • Organs –
• connective tissues heart, liver,
• muscles pancreas, gut,
etc.
Deafferentation Sympathetic Peripheral
Maintained

4. • Aching, often constant
• May be dull or sharp
• Often worse with movement
• Well localized
Eg
– Bone & soft tissue
– chest wall

5.  Somatic pain and visceral pain are actually two
very different types of pain. Somatic pain comes
from the skin and deep tissues, while visceral pain
comes from the internal organs. Both somatic pain
and visceral pain are detected the same way:
Nociceptors, or pain-detecting nerves, send an
impulse from the painful site up through the spinal
cord and to the brain for interpretation and
reaction. This is called nociceptive pain, and
differs from neuropathic pain, which is caused by
nerve damage. Though they are detected in similar
ways, somatic pain and visceral pain do not feel
the same

6.  How Somatic Pain Feels
 Somatic pain is generally described as
musculoskeletal pain. Because many nerves
supply the muscles, bones and other soft
tissues, somatic pain is usually easier to
locate than visceral pain. It also tends to be
more intense. Some chronic pain conditions
caused by somatic pain include:

7. • Constant or crampy
• Aching
• Poorly localized
• Referred
Eg
– CA pancreas
– Liver capsule distension
– Bowel obstruction

8.  How Visceral Pain Feels
 Visceral pain is internal pain. It comes from
the organs or the blood vessels, which are
not as extensively innervated, or supplied
by, sensory nerves. Unlike somatic pain,
visceral pain may feel dull and vague, and
may be harder to pinpoint. Some common
types of visceral pain include:

9. COMPONENT DESCRIPTORS EXAMPLES
Steady, • Burning, Tingling • Diabetic neuropathy
Dysesthetic • Constant, Aching
• Post-herpetic
• Squeezing, Itching neuropathy
• Allodynia
• Hypersthesia
Paroxysmal, • Stabbing • trigeminal neuralgia
Neuralgic
• Shock-like, electric • may be a component
• Shooting of any neuropathic
pain
• Lancinating

10.  MECHANORECEPTORS
-Meissner’s Corpuscles (light touch)
- Pacinian corpuscles (deep pressure)
- merkel's corpuscles (deep pressure)
 THERMORECEPTOR
-krause's end bulbs (decrease temperature,
touch )
-ruffini corpuscles( in the skin)
 PROPRIOCEPTOR
-muscle spindle , golgi tendon
 NOCICEPTOR

11.  ACUTE:
 onset is well defined,
 response to tissue injury,
 responds to pain treatment,
 associated with anxiety,
 affects the individual
 CHRONIC PAIN:
 Onset is ill defined,
 response to change in nervous system,
 less response to medication,
 associated with depression,
 involves social network

12.  MELZACK & WALL,1965- Substentia
Gelatinosa(SG) in dorsal horn of spinal cord acts
as a "gate"- only allows one type of impulses to
connect with the SON
 Transmission Cell(T-cell)- distal end of the SON
 If A-beta neurons are stimulated- SG is activated
which closes the gate to A-delta & c neurons
 If B-delta and C neurons are stimulated- SG is
blocked which closes the gate to A-beta neurons

13.  Gate - located in the dorsal horn of the spinal cord
 Smaller, slower nerve carry pain impulses
 Larger, faster nerve fibers carry other sensations
 Impulses from faster fibers arriving at gate 1st inhibit
pain impulses (acupuncture/pressure, cold, heat, chem. skin
irritation).
Brain
Pain
Gate (T
cells/ SG) Heat, Cold,
Mechanical

14.  Descending neurons are activated by:
stimulation of A-delta & C neurons, cognitive
processes, anxiety, depression, previous
experiences, expectations which Cause
release of enkephalins (PAG).
 Enkephalin interneuron in area of the SG
blocks A-delta & C neurons

15.  Least understood of all the theories
 Stimulation of A-delta & C fibers causes release of B-
endorphins from the PAG
 Mechanism of action – similar to enkephalins to block
ascending nerve impulses
 Examples: TENS (low freq. & long pulse duration)

16.  Unlike specificity theory, pattern theory
suggests that there are no separate systems for
receiving pain, but instead the nerves are shared
with other senses like touch.
 The most important feature of pain is the
pattern of activity in the nervous system. So, too
much stimulation (eg too much touch) will cause
pain.

17.  Reduce pain!
 Control acute pain!
 Improve healing process
 Reduce inflammation and edema
 Decrease spasm and improve muscle
contraction

18.  Use to control pain
 Muscle spasm decrease as result of
 decrease activity in gamma motor efferent,
 decrease excitability of muscle spindle and
 increase activity of Golgi tendon organs

19.  Moist heat packs and paraffin are examples
of therapeutic conductive heating
 Therapeutic convective heating take place
during hydrotherapy
 Therapeutic radiant is supplied infrared

20.  Cold therapy is the best modality for acute
inflammatory reactions like:
 Acute inflammation of the bursa (bursitis)
 Epicondylitis (tennis elbow, golfer’s elbow)
 Acute trauma
 Cold therapy reduce:
 Muscle spasm secondary to:
 Underlying joint and skeletal pathology
 Nerve root irritation
 Edema, hyperemia (excess blood in tissue) and pain
 Due to its vasoconstrictive (constriction of blood
vessels) effect

21.  A local decrease in tissue temperature
 Reduction in metabolism
 Vasoconstriction (initially)
 Reduce blood flow (initially),
 Reduce muscle excitability, muscle spindle
activity
 Reduce nerve conduction velocity
 Reduction in lymphatic and venous drainage
 Reduce Decrease formation and accumulation of
edema
 Anesthesia

22.  After some minutes the vasoconstriction may
give way to a marked vasodilatation which it self
may last some 15minute before being replaced
by another episode of vasoconstriction
 This alteration is called the “Lewis hunting
reaction” (Lewis, 1930), in the sense that the
vessels hunts about its mean position

23.  Electromagnetic waves that produce heat
 Frequency of 27.12 MHz and wavelength > 11 m.
 Use in
 muscle spasm- pain relief,
 Delayed healing
 Chronic inflammation- increase blood circulation
 Fibrosis- increases extensibility of fibrous tissue

24.  Principle effect is production of heat in the tissues
↓
 rise temperature of that part
↓
 Relaxation of muscle and increase the efficiency
of their action
↓
 Increase blood supply ensuring the optimum
condition for the muscle contraction.

25. parameters Chronic condition Acute condition
Intensity comfortable warmth Below sensation of
warmth
Duration 20 minutes 10 minutes
Frequency Daily Twice a day

26.  Electromagnetic radiation
 Frequency 2450 MHz and wavelength 12.245 cm
 Relief pain- in traumatic
and rheumatic condition
 Muscle spasm
 Inflammation- increase blood supply and resorption
of edema
 Delayed healing- promote healing

27.  Principle effect is production of heat in the tissues
↓
 rise temperature of that part
↓
 Relaxation of muscle and increase the efficiency of
their action
↓
 Increase blood supply ensuring the optimum
condition for the muscle contraction.

28.  To produce deep tissue heat by molecular friction
 It helps to:
 Decrease the joint pain
 Prepare the joint for mobilization/manipulation
 It can break adhesions and calcification
(e.g. calcific bursitis)
 Combined with deep tissue massage (trigger point
therapy) it is effective for treatment of myofascitis

29.  It is impossible to treat C or A fiber
selectively, ultrasound provides both pain
relief and relief from muscle spasm
 Sounding of C fibers produce pain relief
whereas sounding of large diameter fibers
bring relief of spasm by changing gamma
fiber activity, making muscle fiber less
sensitive to stretch.

32.  Transcutaneous Electrical Nerve stimulation
 TYPES
 High tens or conventional tens
(high freq:100-150Hz, law intensity:12-30mamp)
 Low tens or acupuncture tens
(high intensity:300mamp, law freq:1-5Hz)
 Burst tens(50-150Hz)
 Brieftens
(high freq:100Hz, law intensity:20-50mamp)
 Modulated tens

34.  Tens selectively stimulates the low-
threshold, large-diameter A-beta fibers
 It resulting in presynaptic inhibition within
the dorsal horns
 Tens delivered at low rate is thought to
facilitate elevation of the level of
endogenous opiates in the CNS

35. Pulse shape Rectangular type impulses
Pulse width 100 microsecond, generally 50
microsec- 300 microsec
Inensity 0 – 60 milliamp, satisfactory
intensity till tingling sensation
Frequency range effect
1 – 250 pulse per second decrease pain
50 – 100 pps sensory level (high level)
2 – 3 pps Motor level (low level)
2 pps Increase in the pain threshold

36.  short frequency therapeutic current
 Types
 Plain
 Surged faradic
 Its use
 Muscle contraction that is inhibited by pain
 Pumping action which result in increase venous
and lymphatic returns

37.  Chemical ions are driven through the skin by small
electrical current
 Ionizable compounds are placed on the skin under the
electrode, which when polarized by direct(galvanic)
current, repels the ion of like charge into the tissue
 Ions are known to be effective analgesics:
 Xylocain
 Hydrocortisone
 Manesium
 Iodine
 salicylate

38.  Light amplification by stimulated emission of
radiation
 A low intensity laser therapy is used
 It resolve inflammation and infection
 Reduce pain
 Increase speed, quality and strength of tissue repair
 TYPES:
 Rubby laser,
 Helium-neon laser,
 Diod laser

39. Laser―photons
↓
Visible red light absorbed in the mitochondria,
infrared light absorbed at the cell membrane
↓
Single oxygen production
↓
Formation of proton gradients across cell membrane and
across membrane of mitochondria
↓
Physiological changes
Change in cell membrane permeability
Increase ATP levels-DNA production
Influences cell metabolism
↓
Activation of regulatory process

40. 1) Power Density (W/cm2) =
Laser Output Power (W)/Beam area (cm2)
2) Beam Area (cm2) = Diameter(cm)2 x 0.7854
3) Energy (Joules)=Laser Output Power (Watts) x Time(Sec)
4) Energy Density (Joule/cm2)=Laser Output Power (Watts) x
Time(Sec)/Beam Area (cm2)
5) Treatment Time (Seconds)=Energy Density
(Joules/cm2)/Output Power Density (W/cm2)

41. THANK
YOU!