PAIN AND PAIN SYNDROMESDayna Ryan, PT, DPT

Winter 2012

Neuropathic Pain (excluding headache)

• What will the patients tell you?• numbness / tingling / pins / shooting / needles /

uncomfortable / burning

• Definition of pain • “...unpleasant sensory and emotional experience

associated with actual or potential tissue damage, or described in terms of such damage…”

• Neuropathic pain caused by direct lesions or disease affecting somatosensory pathways • e.g. sensory nerves, nerve roots, thalamus, cortex

Central Post-Stroke Pain Syndrome

• Overview• First described by Déjerine & Roussy in 1906 as “Thalamic Pain Syndrome”

• Characterized by gradual onset of neuropathic pain & sensory disturbances after stroke (~50% within 1 month of stroke)

• Vascular lesions in somatosensory pathways in the brain, especially spinothalamic cortical tract

• Etiology is central sensitization

•Signs & Symptoms• Distribution of symptoms

• Sensory disturbances• Abnormal sensation • Allodynia: pain evoked by stimuli that is usually not painful (e.g. touch or brush)

• Neuropathic pain• A variety of qualities: burning, pricking, aching, lacerating, shooting, squeezing

• Spontaneous• Evoked, elicited by mechanical or thermal stimuli• Intense, 3-6 on 10 point scale• Usually a daily pain with varying pain-free intervals lasting a few hours at the most

•Diagnosis• History of pain • Imaging confirming a CNS lesion (CT, MRI)• Comprehensive somatosensory test• Rule out other causes

•Treatment• Antidepressants (amitriptyline)• Anticonvulsants (gabapentin)• TENS is occasionally helpful

Migraine• Overview

• Varies in intensity, frequency, duration• Commonly unilateral• Associated with anorexia, nausea & vomiting• Some are preceded by neurologic & mood disturbances

• Incidence• 6% of men / 18% of women = 1/3• 1st attack before age 40 in 90% of patients

Lesion involves vasculatures of the brain (blood vessels dilation cause headache)

Etiology: unknown• Genetic factors • Environmental factors, e.g. stress, pain

• Phases of Migraine• Prodrome: last hours or days• Aura: last < 1 hour prior to pain• Headache: last 4 to 72 hours• Postdrome: hours or days after pain

• Classification of Migraine• Migraine with aura• Migraine without aura

Visual aura

Signs & Symptoms• Prodrome

• Mood disturbances, loss or changes in appetite• Aura

• Focal neurological symptoms• #1 visual disturbances; #2 paresthesias

• Headache• Episodic, commonly unilateral, build up gradually• Dull, throbbing pain• Nausea, vomiting, fatigue, pallor• Photophobia, sonophobia, blurred vision• Aggravated by physical activities

• Postdrome• Fatigue, aching, tender head• Increased urination (i.e. diuresis)

• Diagnosis• History• Occasionally EEG (focal slowing)

• Treatment• Acute

• NSAID, narcotics• analgesics (+caffeine)• rest in dark & quiet place

• Prophylactic medication• PT

• Biofeedback• C-spine manipulation & modalities• Sleep

Cluster Headache

• Overview• Rare but most painful • Episodic (80% of patients)• Chronic (pain >= 12 months without remission)• Primarily in men age 20 to 50• Black males

• Lesion Site: vasodilation of one external carotid artery

• Etiology• Vasodilatation ipsilateral to the pain• ANS dysfunction (activation of trigeminal vascular & parasympathetic

systems) • Genetic link

Signs & Symptoms• Pain

• Sudden, excruciating, mostly unilateral• Orbital & frontotemporal• Boring & non-throbbing• Short duration (15-180 min)• Wake patient up from sleep

• Autonomic symptoms• Ipsilateral to the headache• Photophobia• Tearing, nasal congestion• Horner’s syndrome

• constricted pupils• droopy eyelid

• Diagnosis• History

• Treatment• Avoid precipitating factors

• alcohol• abrupt changes of sleeping patterns• anger, anxiety• altitude > 5000 feet• laying down

• Ergotamine (vasoconstrictor)• Biofeedback & exercise

Muscle Tension Headache

• Overview• Most common type of headache• “bandlike”, “tightness” head pain• Intermittent, recurrent, or chronic

• Etiology• Lesion site: Musculoskeletal disorders at C-spines, TMJ, and atlanto-occipital joint

• Previous trauma to neck• Abnormal neck & trunk posture• Stress increases muscle tension• More common in women

Signs & Symptoms• Pain

• Bilateral forehead, temples, or back of head & neck

• Radiates to neck & shoulders• Non-Pulsating, vasoconstricting, moderate intensity

• Last <= 7 days• Minimum aggravation by physical activity

• Tender scalp, rigidity/spasm of neck

•Diagnosis• History, rule out other causes, referred pain

•Treatment• NSAID or anagelsics (+ caffeine), TCAs• Biofeedback, massage, heat

Trigeminal Neuralgia (CN V)• Etiology

• Unknown• Herpes zoster, multiple sclerosis, tumors

• Demyelination• pain fibers become hyper-excitable in

response to mechanical stimulation (e.g. pressure, touch)

• Incidence• More common in women• More common in older adults age 50-70

• Spontaneous remission in some cases

•Signs & Symptoms • Sudden onset• “like a lightning bolt inside my head that lasts for seconds to minutes”

• Sharp, shooting pain• Most common in 5th CN V2 (maxillary) & V3 (mandibular) branches

•Diagnosis• History• No sensory or motor impairment• Imaging studies to rule out other causes

•Treatment• Anticonvulsant (Tegretol)• Neurosurgical procedure (rhizotomy)

Post-Herpetic Neuralgia: “shingles”

• Etiology• Reactivation of varicella zoster virus (chicken pox) causes inflammation in cranial or dorsal roots ganglia

• Demyelination & degeneration of affected nerves secondary to inflammation

• Onset & Course• Mostly in older adults age 50 to 70• Immuno-compromised individuals at risk• 1%-2% (rarely) develops motor paralysis• Prognosis is good unless motor neurons or vision is affected

• Early Signs & Symptoms• Fever, malaise, GI disturbances• Tingling and pain, followed by rash and blisters along affected dermatomes

• Thoracic & trigeminal most commonly affected• Skin lesions last ~ 1 month

• Later Signs & Symptoms• Pain

• chronic• severe • constant• aching, burning, cutting, stabbing

• Diagnosis• Clinical presentation

• Treatment• Treat symptoms. No cure.• Corticosteroids (for itching), antiviral (Acyclovir)• Analgesics, Lidocaine patches • Controlled-release oxycodone

• Implications for PT• Relaxation • Avoid heat & ultrasound• Get vaccinated yourself! • Don’t touch the skin lesions! (Contagious!)

• Overview– usually affect arm or leg– uncommon, chronic condition– Classification

• CRPS1: Type 1 (“Reflex Sympathetic Dystrophy”)– 90% of cases– Occurs after an illness or injury that did not

directly damage the nerves • CRPS2: Type 2

– Occurs after a distinct nerve injury• Etiology: secondary to some type of trauma usually• Lesion site: Overactive sympathetic efferent fibers

Complex Regional Pain Syndrome

• General Signs & Symptoms• Intense burning or aching pain• Swelling (cycles with pain)• Trophic skin changes

• Thinning• Shininess• Loss of wrinkling

• Stages • Stage 1

• Pain increases with stress• Changes in skin & nails

• Stage II• Tremor, dystonia, inability to initiate movements• Joint stiffness, swelling

• Stage III• Muscle atrophy• Joint contracture

• Diagnosis• X-ray, bone scan identifies the bone affected • Thermographic to study skin temperature• Sympathetic ganglion block will abolish pain

• Medications• Sympathetic nerve block• Corticosteroids (prednisone)• NSAIDs for pain and inflammation• Antidepressants (amitriptyline) & anticonvulsants

(neurotin)• Intrathecal Baclofen to control dystonia• Implanted dorsal column stimulation to reduce pain• PT to increase mobility, TENS, modalities

Phantom Limb Pain• Overview

– Pain is felt distal to residual limb– Pain varies from mild electrical shock, tingling, to

intense shooting, throbbing or burning

– Present in 75% of amputee, persistent & chronic in ~ 5% of amputees

– Prognosis is poor with pain > 6 months

• Etiology– Overactive central pain pathways due to loss of

peripheral sensory inputs– Maladapted cerebral cortex remapping

• Treatment• Anesthesia to brachial plexus fibers• Pain medications• Surgery to remove scar entangling a nerve• Mirror Therapy• Virtual Reality• Biofeedback, relaxation• Heat & massage (PT)• TENS (PT)