Nociceptive Pain
Nociceptive pain is the
most common type of pain, a normal reaction of a healthy nervous system to a tissue‑damaging stimulus. It arises from the
stimulation of nociceptors - specialized pain receptors found in skin, muscles, joints and internal organs. Its role is
protection of the body, alerting us to burns, cuts or bruises and prompting a
withdrawal or protective reaction to the injured area.
A characteristic feature of
nociceptive pain is that its intensity is generally
proportional to the degree of tissue damage. Additionally, it
subsides as the wound heals and eventually disappears. Nociceptors can be triggered by
mechanical, thermal, or chemical stimuli, producing different qualities of pain.
Nociceptive pain typically
responds well to painkillers from the NSAID group or to paracetamol. It is a pain that the body
recognizes, and usually does
not cause permanent nerve damage.
Superficial Somatic Pain
This is a subtype of nociceptive pain originating from the
body’s surface layers, that is skin and subcutaneous tissue. It is characterized by a
very precise localization, since the patient is able to pinpoint the painful spot exactly. The pain is perceived as
sharp, burning, stabbing or cutting, depending on the type of injury.
Typical examples of
superficial somatic pain include a knife cut, a skin abrasion, or a first‑degree burn. Because of the high density of receptors in the skin, this type of pain is often intense and appears immediately.
The body responds with a
reflex - for example withdrawing the hand from a hot surface. Because the
pain source is visible, diagnosis is usually straightforward, and treatment typically consists of
local wound care and possibly peripheral analgesics.
Deep Somatic Pain
This pain arises from
deeper structures of the musculoskeletal system - mainly muscles, tendons, ligaments, bones and joints. Unlike superficial pain, it is often
difficult to localize precisely. Deep somatic pain is usually described as
dull, diffuse and often radiating to surrounding areas, and may be accompanied by
reflex muscle tension around the painful site.
Common causes are
sports injuries, such as sprains or dislocations, but also overuse or degenerative changes in joints. Because there are
fewer nociceptors in deep tissues than in skin, the pain develops more slowly, but can
last much longer and be more intrusive.
A frequent phenomenon with
deep somatic pain is referred pain - for example a hip joint problem perceived as knee pain. Treatment usually requires a combination of
medication and physiotherapy to restore function of the affected structure.
Visceral Pain
Visceral pain originates from
internal organs - those in the chest, abdomen or pelvis. This type of pain is
distinctive because internal organs do not react to cuts or burns but are extremely sensitive to
stretching, lack of oxygen or inflammation. Visceral pain is often
poorly localized, deep and pressing, but it can also be colicky.
Characteristic for
visceral pain are autonomic symptoms such as
nausea, vomiting and sweating, often with pallor of the skin. Pain may also be referred to distant, seemingly unrelated areas - e.g. gallbladder pain radiating to the right shoulder blade.
Due to the complex
nerve supply of internal organs, visceral pain often causes severe anxiety and psychological discomfort. Treatment must focus not only on
pain relief, but primarily on
addressing the underlying organ disease.
Inflammatory Pain
This pain results from the
immune system’s reaction to tissue damage or infection. In the affected area a chemical “inflammation soup” is released - a mixture of prostaglandins, histamine and cytokines - which strongly
irritate nerve endings and lower their activation threshold.
As a result, the affected area becomes
hypersensitive to touch (hyperalgesia), red and warm. Inflammatory pain occurs in conditions such as
rheumatoid arthritis or after surgical procedures. Frequently, the pain
intensifies at night or in the morning and diminishes with movement.
Inflammatory pain has a
protective function, forcing rest of the affected area and promoting healing. The most effective therapy is with
anti‑inflammatory medication (NSAIDs) that block production of inflammatory mediators and interrupt the biochemical cascade causing pain.
Neuropathic Pain
Neuropathic pain does not result from tissue damage, but from
dysfunction or injury of the nervous system itself. It is effectively a
false alarm sent by impaired nerve structures. Patients often describe it with terms like burning, heat, electric shock, tingling or numbness.
It is often a
chronic pain, difficult to treat and frequently
resistant to standard painkillers. Sensory disturbances often accompany it - such as
allodynia (pain from normally non‑painful stimuli) or
hypoesthesia (reduced sensation).
Common causes include conditions like
diabetes (diabetic neuropathy),
shingles (herpes zoster), spinal injuries or chemotherapy. Treatment typically relies on
medications that modulate the nervous system, such as anticonvulsants or antidepressants.
Peripheral Neuropathic Pain
This type affects nerves of the
peripheral nervous system, i.e. outside brain and spinal cord. It can involve a
single nerve (mononeuropathy) - e.g. the
carpal tunnel syndrome - or multiple nerves (polyneuropathy).
Symptoms typically appear in the
area innervated by the affected nerve - in polyneuropathy often in
distal limbs, i.e. hands and feet. Patients commonly experience altered sensation like tingling or numbness (“glove and stocking” distribution).
Regeneration of peripheral nerves is often slow and not guaranteed. Therapy focuses on
symptom relief and - importantly - on
protecting nerves from further damage, for example through control of blood sugar in diabetes.
Central Neuropathic Pain
This pain results from damage to the
central nervous system - the brain or spinal cord. It is considered one of the
most difficult pain types to treat. Conditions such as
stroke,
multiple sclerosis or spinal cord injury may be causes.
The pain may affect
large body areas, in stroke even an entire side of the body. Patients often describe it as
constant, unbearable burning or icy cold, sometimes with sudden stabbing pain attacks. Because pain‑inhibiting pathways are damaged, the brain
misinterprets signals or generates them spontaneously.
Treating
central neuropathic pain is a major challenge. Often a
multimodal approach is required - for example
neurostimulation (implantation of a spinal cord stimulator) plus intensive
neurological rehabilitation so that the brain relearns correct pain perception.
Neuralgia (Nerve Pain)
Neuralgia affects the area served by a specific nerve or nerves. It is characterized by
sudden, extremely intense and stabbing pain, which clearly distinguishes it from other types. Unlike classic chronic neuropathic pain, neuralgia often comes on
abruptly and shock‑like.
A common example is
trigeminal neuralgia, where simple acts like brushing teeth or a breeze may cause
paralyzing pain in half the face. Another example is
intercostal neuralgia, from irritation or damage to intercostal nerves. Often the cause is a
neurovascular conflict - pressure of a blood vessel on a nerve.
Treatment aims to
stabilize the nerve membrane to prevent uncontrolled electrical discharges. Sometimes
invasive procedures are needed, like nerve blocks. Increasingly common are
decompression surgeries (e.g. microvascular decompression) to relieve physical pressure on the nerve.
Mixed Pain
In clinical practice pure forms of pain are rare. Therefore the term
mixed pain refers to pain that has both nociceptive and neuropathic components. This is most common in
chronic back pain or
cancer pain.
An example is a
herniated disc: the injured disc may cause inflammation (nociceptive pain) and at the same time compress a nerve root - producing neuropathic symptoms such as sciatica. Differentiating these components is crucial for effective pain therapy, because anti‑inflammatory drugs alone will not relieve nerve pain.
Treatment of
mixed pain requires a
multimodal approach. This means combining
anti‑inflammatory drugs, neuropathic pain medications, physiotherapy and psychological methods. Only an approach from several angles can offer a real chance of relief.
