ABPMR Pain Medicine flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

A-delta fibers

Myelinated, fast-conducting primary afferents that transmit sharp, well-localized first pain; their activation precedes the slower dull pain carried by unmyelinated C fibers.

Gate control theory

Non-painful A-beta input activates inhibitory interneurons in the dorsal horn and reduces transmission of nociceptive signals, explaining why vibration or TENS can relieve pain.

Mu opioid receptor

G-protein coupled receptor mediating analgesia, euphoria, respiratory depression, miosis, and constipation; most clinical opioids are mu agonists, and OPRM1 variants may alter response.

Local anesthetic pKa

The pKa determines the fraction of uncharged drug able to cross the lipid membrane; acidic, inflamed tissue lowers that fraction and delays onset of the block.

COX-2 inhibition

Reduces prostaglandin synthesis at inflamed sites and in the central nervous system, giving analgesia and anti-inflammatory effects; selective inhibitors spare gastric COX-1 but raise cardiovascular risk.

Spinothalamic decussation

Second-order nociceptive neurons cross the anterior white commissure within one or two segments of entry before ascending in the lateral spinothalamic tract, so cord lesions cause contralateral sensory loss.

Descending pain inhibition

Periaqueductal gray neurons project to the rostral ventromedial medulla, which sends serotonergic and noradrenergic fibers to the dorsal horn to suppress nociceptive transmission.

Red flag for back pain

Features such as fever, unexplained weight loss, night pain, cancer history, intravenous drug use, saddle anesthesia, or bowel and bladder dysfunction that mandate prompt imaging and workup.

Straight leg raise test

With the patient supine, passive hip flexion with an extended knee between 30 and 70 degrees reproduces radicular pain, suggesting L5 or S1 nerve root irritation.

Spurling test

Cervical extension, ipsilateral rotation, and axial compression narrow the neural foramen and reproduce radicular arm pain, indicating cervical nerve root compression.

Neuropathic pain screening

The DN4 questionnaire scores burning, painful cold, electric shocks, tingling, pins and needles, numbness, and tactile allodynia; a score of 4 or more suggests neuropathic pain.

Neurogenic claudication

Leg pain and heaviness provoked by walking and relieved by sitting or forward flexion, caused by lumbar canal narrowing; unlike vascular claudication it improves with flexion and bicycling.

Visceral referred pain

Noxious visceral input converges on the same spinal segments as somatic afferents, so visceral disease produces pain in a distant dermatome, such as gallbladder pain referred to the right shoulder.

Myofascial trigger point

A hyperirritable spot within a taut muscle band that is tender to compression and produces a characteristic referred pain pattern, often accompanied by a local twitch response.

Transforaminal epidural injection

Delivers corticosteroid and local anesthetic through the neural foramen toward the ventral epidural space; the cervical approach carries a small risk of spinal cord infarction from vertebral artery injury.

Medial branch block

Injection of local anesthetic near the medial branch of the dorsal ramus to diagnose facet joint pain; at least 50 percent relief is commonly required before radiofrequency ablation.

Stellate ganglion block

Anterior paratracheal injection at C6 that blocks the cervical sympathetic chain; ipsilateral Horner syndrome is expected, and complications include pneumothorax and recurrent laryngeal nerve injury.

Radiofrequency ablation

Thermal or pulsed lesioning of medial branch nerves after a positive diagnostic block; analgesia typically lasts 6 to 12 months and the procedure can be repeated when pain recurs.

Particulate steroid risk

Insoluble corticosteroid aggregates can occlude small arteries; dexamethasone is non-particulate and is often preferred when injecting near the cervical spine or the vertebral artery.

Spinal cord stimulation trial

A temporary percutaneous lead is placed to confirm that stimulation relieves pain before a permanent generator is implanted; paresthesia-free waveforms are now available.

Acetaminophen maximum dose

Adult dosing is generally capped at 3 to 4 grams daily, with a lower limit in liver disease or chronic alcohol use; overdose causes dose-dependent hepatic necrosis.

Morphine milligram equivalents

A standardized conversion used to quantify total opioid exposure; 30 mg oral morphine equals roughly 20 mg oxycodone and 30 mg hydrocodone, but methadone conversion is nonlinear.

Gabapentinoid use

Gabapentin and pregabalin bind the alpha-2-delta subunit of voltage-gated calcium channels and reduce neurotransmitter release; they are first-line for neuropathic pain and need renal dose adjustment.

Duloxetine

A serotonin-norepinephrine reuptake inhibitor approved for painful diabetic peripheral neuropathy, fibromyalgia, and chronic musculoskeletal pain; benefit is independent of depression and blood pressure may rise.

Lidocaine patch

A 5 percent topical lidocaine patch provides local analgesia with minimal systemic absorption and is indicated for postherpetic neuralgia; it is applied for up to 12 hours daily.

Triptan contraindication

Triptans are 5-HT1B/1D agonists that constrict cranial and coronary vessels; they are contraindicated in ischemic heart disease, uncontrolled hypertension, and hemiplegic or basilar migraine.

Biopsychosocial model

Explains pain as the interaction of biological, psychological, and social factors; treatment targets all three rather than nociception alone, which supports multidisciplinary rehabilitation.

Fear-avoidance model

Catastrophic interpretation of pain leads to fear, avoidance of activity, disuse, and worsening disability; graded exposure to feared movements interrupts this cycle.

Cognitive behavioral therapy

Structured therapy that identifies and restructures maladaptive pain-related thoughts and behaviors, with training in relaxation and pacing; it improves function and distress in chronic pain.

Graded activity pacing

Setting baseline activity levels and increasing them by planned quotas while alternating activity and rest, rather than working until pain flares; this reduces flare-ups and builds tolerance.

Functional restoration

Interdisciplinary program combining physical conditioning, occupational therapy, and psychological or vocational intervention to restore function and return to work in chronic disabling pain.

Yellow flags

Psychosocial risk factors such as catastrophizing, fear-avoidance beliefs, anxiety, depression, and low work satisfaction that predict transition from acute to chronic pain and disability.