II. Definitions: Categories of Peripheral Nerve Injury

  1. Neuropraxia
    1. Least severe Peripheral Nerve Injury
    2. Myelin fibers surrounding the axon are injured focally
    3. Axon and connective tissue sheath remain unharmed
    4. Limited duration of injury (typically days to weeks)
  2. Axonotmesis
    1. Axon injury, but preserved connective tissue framework
    2. Risk of distal nerve degeneration
    3. Recovery over months to years and frequently incomplete nerve regeneration with residual deficit
  3. Neurotmesis
    1. Most severe Peripheral Nerve Injury and least common of the three nerve injury types
    2. Complete axon disruption, as well as disrupted connective tissue framework
    3. Normal regeneration of the nerve is uncommon and signficant persistent deficit is the norm

III. Pathophysiology

  1. Mechanisms of nerve injury
    1. Direct pressure
    2. Repetitive microtrauma
    3. Stretch-induced ischemia
    4. Compression-induced ischemia
  2. Degree of nerve injury may progress to nerve fibrosis with greater nerve injury
    1. Severity of injury mechanism
    2. Duration of exposure to compression or other mechanism

IV. Causes: Upper Extremity

  1. Images
    1. neuroPeripheralArm.jpg
    2. brachialPlexus.jpg
  2. Cervical Spine and Cervicobrachial (Axilla)
    1. Cervical Disc Disease
    2. Brachial Plexus Burner
  3. Shoulder
    1. Shoulder Band Syndrome (Reflex Sympathetic Dystrophy)
    2. Quadrilateral Space Syndrome (Axillary Nerve Injury)
    3. Long Thoracic Nerve Injury
      1. Injury: Direct blow to Shoulder or chronic repetitive overhead Shoulder traction (e.g. tennis, swimming, baseball)
      2. Symptoms: Diffuse Shoulder or Neck Pain with overhead activity
      3. Exam: Forward flexion weakness at Shoulder and Scapular Winging
    4. Spinal Accessory Nerve Injury
  4. Humerus
    1. Radial Nerve Injury at the Humerus
      1. Radial Nerve may be compressed in axilla causing Saturday Night Palsy
      2. Mid-shaft Humerus Fracture may injure Radial Nerve
      3. Radial Nerve may be entrapped in radial groove
  5. Elbow and Forearm
    1. Cubital Tunnel (Ulnar Nerve, common)
    2. Radial Tunnel (and related Posterior Interosseus Nerve Syndrome)
  6. Wrist and Hand
    1. See Overuse Syndromes of the Hand and Wrist
    2. Carpal Tunnel Syndrome (Median Nerve, very common)
    3. Ulnar Tunnel Syndrome (Cyclist's Palsy)
    4. Handcuff Neuropathy (Radial Nerve)

VI. Causes: Miscellaneous

VII. History

  1. See Neuropathy
  2. Musculoskeletal Injury or Trauma to affected region
  3. Course of symptoms
  4. Provocative activities

VIII. Exam

  1. Musculoskeletal Exam of affected region
    1. Joint range of motion
    2. Specific joint exam for region
  2. Neurologic Exam
    1. See Motor Exam
    2. See Sensory Exam
    3. See Deep Tendon Reflex

IX. Symptoms

  1. Burning pain
  2. Numbness
  3. Paresthesias
  4. Motor Weakness

X. Differential Diagnosis

XI. Imaging

  1. See Peripheral Neuropathy
  2. Modalities
    1. Ultrasound
      1. Real-time (point-of-care) evaluation of compression sites that reproduce symptoms
      2. Directed Corticosteroid Injection for certain compression neuropathies
    2. Magnetic Resonance Imaging (MRI)
      1. Identifies most likely sites and mechanisms of compression
      2. Identifies signs of Muscle atrophy suggestive of Muscle denervation
  3. Indications
    1. Severe weakness
    2. Multiple nerves involved
    3. Refractory course to 6-8 weeks of specific conservative therapy

XII. Diagnostics: Electrodiagnostic Testing

  1. See Peripheral Neuropathy
  2. Modalities (typically performed together)
    1. Nerve Conduction Study
    2. Electromyography (EMG)
  3. Indications
    1. Localization of nerve lesion in atypical presentations
    2. Monitoring of nerve injury progression during management
    3. Presurgical planning

XIII. Management

  1. See Peripheral Neuropathy
  2. Initial conservative therapy is preferred for most non-Traumatic compression neuropathies
    1. Management is specific to the Neuropathy
  3. General conservative measures
    1. Patient Education regarding likely diagnoses and causative factors
    2. Relative rest with activity modification
    3. Consider bracing or Splinting (with care not to further compress underlying nerve)
    4. Consider physical therapy
  4. Surgical Management
    1. Indicated in refractory cases
    2. Lack of full resolution with surgery is common
    3. Surgical options depend on specific Neuropathy
      1. Nerve Decompression
      2. Surgical exploration for underlying cause
      3. Nerve transfer

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Related Studies

Ontology: Nerve compression syndrome (C0027743)

Definition (MSH) Mechanical compression of nerves or nerve roots from internal or external causes. These may result in a conduction block to nerve impulses (due to MYELIN SHEATH dysfunction) or axonal loss. The nerve and nerve sheath injuries may be caused by ISCHEMIA; INFLAMMATION; or a direct mechanical effect.
Concepts Disease or Syndrome (T047)
MSH D009408
English Compression Syndrome, Nerve, Compression Syndromes, Nerve, Nerve Compression Syndrome, Nerve Compression Syndromes, Syndrome, Nerve Compression, Syndromes, Nerve Compression, Nerve Compression Syndromes [Disease/Finding], trapped nerve, compression neuropathy, entrapment neuropathy, nerve trap, neuropathy entrapment, entrapment neuropathies, trap nerve, nerve compression syndrome, nerve compression syndromes, nerve entrapment syndrome, compression neuropathies, Nerve compression syndrome
Swedish Nervkompressionssyndrom
Czech syndromy komprese nervů, neurovaskulární konflikt, tunelové syndromy, úžinové syndromy
Finnish Hermopinneoireyhtymät
Russian NEVROPATIIA SOPUTSTVUIUSHCHAIA, NERVA SDAVLENIIA SINDROMY, НЕВРОПАТИЯ СОПУТСТВУЮЩАЯ, НЕРВА СДАВЛЕНИЯ СИНДРОМЫ
Japanese 圧迫性神経障害, 絞扼神経障害, 絞扼性神経障害, 神経絞扼性障害, 神経圧迫性障害, 圧迫・絞扼性神経障害, 絞扼性末梢神経障害, 神経圧迫症候群, 圧迫絞扼性神経障害, 末梢神経圧迫症候群
Croatian ŽIVCI, KOMPRESIVNI SINDROMI
Polish Usidlenie nerwu, Zespoły uciskowe nerwów
Norwegian Nerveinnklemmingssyndromer, Nervekompresjonssyndromer
Portuguese Compressões de Nervos, Aprisionamentos Neurais, Encarceramentos de Nervos, Aprisionamento de Nervos, Compressões Neurais, Neuropatias Compressivas, Síndromes de Compressão Nervosa
French Syndromes de compression nerveuse, Neuropathies de compression
German Nervenkompressionssyndrome
Italian Sindrome da compressione nervosa
Dutch Compressieneuropathie, Neuropathie, compressie-, Compressieneuropathieën, Neuropathieën, compressie-
Spanish Síndromes de Compresión Nerviosa

Ontology: Peripheral Nerve Injuries (C0262593)

Definition (MSH) Injuries to the PERIPHERAL NERVES.
Definition (MSHCZE) Poranění PERIFERNÍCH NERVů. R
Definition (NCI_CDISC) Sensory or motor loss of peripheral nerve function due to a traumatic event.
Definition (NCI) Sensory or motor loss of peripheral nerve function due to a traumatic event. (ACC)
Concepts Injury or Poisoning (T037)
MSH D059348
SnomedCT 157657003, 157648009, 287156003, 73590005
English PERIPHERAL NERVE INJURY, Peripheral nerve injury NOS, injury of peripheral nerve (diagnosis), injury of peripheral nerve, Nerve injury, peripheral, Injury;nerve;peripheral, injury nerve peripheral, peripheral nerve injuries, peripheral nerve injury, Nerve Injuries, Peripheral, Nerve Injury, Peripheral, Injury, Peripheral Nerve, Injuries, Peripheral Nerve, Peripheral Nerve Injuries, Peripheral Nerve Injury, Peripheral Nerve Injuries [Disease/Finding], Peripheral nerve injuries, Peripheral nerve injury NOS (disorder), Peripheral nerve injury, PNI - Peripheral nerve injury, Peripheral nerve injury (disorder), injury; nerve, peripheral, nerve; injury, peripheral, Peripheral nerve injury, NOS
Italian Traumatismi di nervo periferico, Traumatismo di nervo periferico, Lesioni dei nervi periferici
Dutch zenuwletsel, perifeer, letsel; zenuw, perifeer, zenuw; letsel, perifeer, perifere zenuwletsels, perifere zenuwletsel
French Lésion nerveuse, périphérique, ATTEINTE D'UN NERF PERIPHERIQUE, Lésions des nerfs périphériques, Lésions nerveuses périphériques, Lésion d'un nerf périphérique
German Nervenverletzung, peripher, Periphere Nervenverletzung, Periphere Nervenverletzungen, Verletzung peripherer Nerven, Verletzungen der Peripherienerven
Japanese 末梢神経損傷, マッショウシンケイソンショウ
Portuguese LESAO DO NERVO PERIFERICO, Traumatismos dos Nervos Periféricos, Lesões dos Nervos Periféricos, Lesão do Nervo Periférico, Traumatismo do Nervo Periférico, Lesão traumática de nervo periférico, Lesões dos nervos periféricos
Czech Úrazy periferního nervu, Poranění periferního nervu, poranění periferního nervu, periferní nerv - poranění
Spanish lesión traumática de nervio periférico (trastorno), lesión traumática de un nervio periférico, lesión traumática de un nervio periférico (trastorno), Lesión del Nervio Periférico, Traumatismos de los Nervios Periféricos, lesión de nervio periférico, SAI, lesión de nervio periférico, SAI (trastorno), Peripheral nerve injury NOS, injuria de un nervio periférico, lesión traumática de nervio periférico, Lesiones traumáticas de los nervios periféricos, Lesión traumática de nervio periférico
Hungarian Perifériás ideg sérülései, Perifériás ideg sérülése, Idegsérülés, perifériás
Russian ПЕРИФЕРИЧЕСКИХ НЕРВОВ ПОВРЕЖДЕНИЯ, НЕРВА ПЕРИФЕРИЧЕСКОГО ТРАВМА, NERVA PERIFERICHESKOGO TRAVMA, PERIFERICHESKIKH NERVOV POVREZHDENIIA
Polish Uszkodzenie nerwów obwodowych, Urazy nerwów obwodowych
Norwegian Skader i det perifere nervesystemet, Skade i det perifere nervesystemet

Ontology: Axonal neuropathy (C0270921)

Concepts Disease or Syndrome (T047)
SnomedCT 60703000
Spanish Neuropatía axonal, neuropatía axónica (trastorno), neuropatía axónica
French Neuropathie axonale
Dutch axonale neuropathie
Portuguese Neuropatia axónica
German axonale Neuropathie
Italian Neuropatia assonale
Japanese 軸索型ニューロパチー, ジクサクガタニューロパチー
Czech Axonální neuropatie
English axonal neuropathies, axonal neuropathy, Axonal neuropathy, Axonal neuropathy (disorder), Axonal neuropathy, NOS, Axonal Neuropathy
Hungarian Axonalis neuropathia

Ontology: Neurapraxia (C0393872)

Concepts Injury or Poisoning (T037)
SnomedCT 390012000, 135894004, 316927003, 367319009, 230619007, 370509002, 370607005
Dutch neuropraxie NAO, neuropraxie
French Neuropraxie SAI, Neuropraxie
German Neuropraxie, Neurapraxie NNB
Italian Neuroaprassia NAS, Neuroprassia
Portuguese Neuropraxia, Nerurapraxia NE
English [Q] Neuropraxia, neuropraxia, neurapraxia, Neurapraxia NOS, [Q] Neuropraxia (qualifier value), Contusion of peripheral nerve, Neuropraxia, Contusion of peripheral nerve (disorder), Neurapraxia (disorder), Neurapraxia (morphologic abnormality), Neurapraxia
Spanish Neuropraxia, Neuropraxia NEOM, [Q] neuropraxia, [Q] neuropraxia (calificador), contusión del nervio periférico (trastorno), contusión del nervio periférico, neuroapraxia (trastorno), neuroapraxia, neuropraxia (anomalía morfológica), neuropraxia
Japanese ニューラプラキシーNOS, ニューラプラキシー, ニューラプラキシー, ニューラプラキシーNOS
Czech Neurapraxie NOS, Neurapraxie, snížení funkce periferního nervu
Hungarian Neuropraxia, Neurapraxia k.m.n.

Ontology: Entrapment Neuropathies (C1510429)

Concepts Disease or Syndrome (T047)
MSH D009408
SnomedCT 155085004, 45781009
English Neuropathies, Entrapment, Neuropathy, Entrapment, Nerve entrapment syndromes, Compression neuropathy (disorder), Entrapment neuropathies, Compression neuropathy, Nerve entrapment syndrome, Trapped nerve, Entrapment neuropathy, Peripheral nerve entrapment syndrome (disorder), Peripheral nerve entrapment syndrome, neuropathy; entrapment, Entrapment syndrome, NOS, Entrapment neuropathy, NOS, Entrapment Neuropathy, Entrapment Neuropathies
Dutch inklemmingsneuropathie, neuropathie; inklemming, Entrapment
French Syndrome canalaire, Syndromes canalaires, Syndromes tunnelaires
German Neuropathie durch Einengung, Engpaß-Neuropathien
Italian Neuropatia da intrappolamento, Neuropatie da intrappolamento
Portuguese Neuropatia por compressão anatómica, Neuropatias de Encarceramento
Spanish Neuropatía compresiva, Neuropatías de Atrapamiento, neuropatía de atrapamiento, síndrome de atrapamiento, síndrome de compresión de nervio periférico, neuropatía por compresión, síndrome de atrapamiento (trastorno), síndrome de atrapamiento de nervio periférico, síndrome de compresión de nervio periférico (trastorno)
Japanese コウヤクセイニューロパチー, 絞扼性ニューロパチー
Czech Neuropatie tlaková, entrapment neuropatie
Hungarian Becsípődéses neuropathia
Norwegian Inneklemmingsnevropatier

Ontology: Neurotmesis of peripheral nerve (C2960651)

Concepts Injury or Poisoning (T037)
SnomedCT 445900004
English Neurotmesis of peripheral nerve, Neurotmesis of peripheral nerve (disorder)
Spanish neurotmesis de nervio periférico, neurotmesis de nervio periférico (trastorno)

Ontology: Axonotmesis of peripheral nerve (C2960652)

Concepts Injury or Poisoning (T037)
SnomedCT 445869000
English Axonotmesis of peripheral nerve (disorder), Axonotmesis of peripheral nerve
Spanish axonotmesis de nervio periférico, axonotmesis de nervio periférico (trastorno)