Chapter 56 Entrapment Neuropathies Flashcards
Provocative maneuvers
briefly increase pressure
at a site of compression, aid diagnosis by re-creating or
exacerbating symptoms.
When an entrapment neuropathy is clinically suspected
electrodiagnostic testing should be performed to confirm
the diagnosis and exclude other neurologic disorders
If
electrodiagnostic testing suggests that the site of compression
or entrapment is not typical
then magnetic resonance imaging or ultrasonagraphy
should be performed to identify the source of compression
“double crush”
an individual to have two
neuropathic lesions in the same limb involving the same nerves at different sites
Electrodiagnostic testing
provide prognostic
information. Electrodiagnostic testing can often differentiate
myelin dysfunction from axon damage.
neurapraxic
injury when a compressive lesion causes only focal demyelination
Site of Entrapment
of Brachial plexus
Anterior and medial scalene muscle
Subclavius muscle
Pectoralis minor and coracoid process
Cervical rib or band, medial antebrachial cutaneous nerve
Site of Entrapment
of Suprascapular
Transverse scapular ligament, scapular notch or foramen
Spinoglenoid ligament or notch
Site of Entrapment
of Musculocutaneous
Coracobrachialis muscle
Brachial fascia, lateral antebrachial cutaneous nerve
Site of Entrapment
of Axillary
Quadrangular foramen or lateral axillary hiatus (long head of
triceps, teres major and minor)
Site of Entrapment
of Radial
Lateral intermuscular septum
Arcade of Frohse (supinator), leash of Henry (brachioradialis,
extensor carpi radialis brevis), Monteggia lesion
Superficial branch
Site of Entrapment
of Median
Ligament of Struthers (supracondylar process: medial
epicondyle)
Pronator teres muscle, sublimis bridge (flexor digitorum
sublimis), lacertus fibrosis
Gantzer’s muscle (flexor pollicis longus)
Transverse carpal ligament
Transverse metacarpal ligament
Site of Entrapment
of Ulnar
Arcade of Struthers (internal brachial ligament, medial head of
triceps, medial intermuscular septum)
Epicondylo-olecranon ligament, cubital tunnel retinaculum,
arcuate ligament of Osborne
Humeroulnar aponeurosis (flexor carpi ulnaris)
Deep flexor-pronator aponeurosis
Guyon’s canal (piso-hamate ligament, volar and transverse
carpal ligament
Deep branch
Transverse and oblique heads of adductor pollicis
Site of Entrapment
of L5 spinal
Iliolumbar ligament (fifth lumbar: wing of the ilium)
Site of Entrapment
of Ilioinguinal
Transverse abdominis muscle
Site of Entrapment
of Genitofemoral
Inguinal canal
Site of Entrapment
of Lateral femoral cutaneous
Inguinal ligament at anterior superior iliac spine
Site of Entrapment
of Femoral
Iliopectineal arch
Hunter’s canal (vastus medialis, adductor longus, sartorius), subsartorial canal
Infrapatellar branch of saphenous nerve
Site of Entrapment
of Obturator
Obturator canal
Site of Entrapment
of Sciatic
Pyriformis muscle
Greater and lesser sciatic foramens, sciatic notch, Gibraltar of the gluteus
Site of Entrapment
of Common peroneal
Fibular neck, peroneus longus muscle
Crural fascia, superficial branch
Inferior external retinaculum (ligamentum cruciforme)
Syndrome of Site of Entrapment of Brachial plexus
Anterior scalene syndrome
Costoclavicular syndrome
Hyperabduction syndrome
Thoracic outlet syndrome
“Rucksack” palsy
Syndrome of Site of Entrapment of Axillary
Quadrilateral space syndrome
Syndrome of Site of Entrapment of Radial
“Saturday night” palsy, “honeymooners’”
palsy
Supinator syndrome, posterior interosseous
syndrome, radial tunnel syndrome, tardy
radial palsy, “tennis elbow,” “frisbee flinging”
Cheiralgia paresthetica, Wartenberg’s disease,
“hand-cuff” or “wristwatch” neuropathy
Syndrome of Site of Entrapment of Median
Pronator syndrome, flexor digitorum sublimis syndrome
Anterior interosseous syndrome, Kiloh-Nevin
syndrome
Carpal tunnel syndrome
Intermetacarpal tunnel syndrome, “bowlers’
thumb”
Syndrome of Site of Entrapment of Ulnar
Cubital tunnel syndrome
“Tardy” ulnar palsy
Ulnar tunnel syndrome, “cyclists’” palsy
(Radfahrerlahung)
Piso-hamate hiatus syndrome
Syndrome of Site of Entrapment of T2–6 posterior rami
Notalgia paresthetica
Syndrome of Site of Entrapment of L5 spinal
Lumbosacral tunnel syndrome
Syndrome of Site of Entrapment of Lateral femoral cutaneous
Meralgia paresthetica, Roth’s meralgy,
Bernhardt’s syndrome
Syndrome of Site of Entrapment of Femoral
Iliacus tunnel syndrome
Gonyalgia paresthetica, “housemaids’ knee”
Syndrome of Site of Entrapment of Obturator
Howship–Romberg syndrome
Syndrome of Site of Entrapment of Sciatic
Pyriformis syndrome
Syndrome of Site of Entrapment of Common peroneal
“Cross leg” palsy
(Anterior) tarsal tunnel syndrome
Site of Entrapment of Posterior tibial
Canal calcaneen de Richet (ligamentum laciniatum)
Medial plantar nerve
Medial plantar proper digital nerve
Transverse metatarsal ligament
Syndrome of Site of Entrapment of Posterior tibial
(Posterior) tarsal tunnel syndrome
“Joggers’ foot,” abductor hallucis tunnel
syndrome
Joplin’s neuroma
Morton’s neuroma (metatarsalgia)
PATHOLOGY of CARPAL TUNNEL SYNDROME
carpal tunnel is at the base of the hand. The
carpal, or wrist bones, form the floor of the tunnel and the flexor retinaculum forms the roof. Nine flexor tendons also pass through the tunnel. Due to this crowded arrangement,
any tenosynovial proliferation, fluid collection, or arthritic
deformity can lead to carpal tunnel syndrome.
Pressure in carpal tunnel increases several fold with
wrist extension or flexion. In those with carpal tunnel syndrome, pressures can reach over 100 mmHg in flexion or extension, pressures high enough to impede flow to the arteries supplying the nerve, causing epineural ischemia. At somewhat lower pressures, venous return can be reduced, resulting in venous
stasis and intraneural edema.
SYMPTOMS of CARPAL TUNNEL SYNDROME
Classically, patients report numbness on the palmar surface of the thumb and index, middle, and half of the ring finger. fifth finger is spared
Carpal tunnel syndrome can cause pain.
The pain can be both distal and proximal to the site of compression. Patients can report pain in the hand, wrist, elbow, and shoulder.
Pain and numbness may increase when the wrist is
flexed or extended.
“flick sign” of Carpal tunnel syndrome
patients often report
symptoms at night when they awake after sleeping with their wrists in flexion. Many patients will report needing to shake their hand on waking to relieve their numbness
Carpal tunnel syndrome Patients usually do not complain of weakness
They may report dropping things or having difficulty with certain motor activities like doing up buttons or opening a jar.
These complaints are probably the result of a combination of mild thenar weakness and sensory loss.
Median Nerve Innervations
The median nerve after it exits the carpal tunnel supplies sensation to the palmar surface of the thumb and index, middle, and half the ring finger. It also supplies the dorsal
tips of these same fingers. Also the median nerve after exiting the carpal tunnel innervates a number of intrinsic hand muscles
The palmar branch of the median nerve spared in carpal tunnel syndrome.
supplies sensation to the proximal portion of the palm and thenar eminence, does not go through the
carpal tunnel, and is therefore