Class 9 Flashcards
What are the nerves of the upper limb?
• Median
• Axillary
• Radial
• Musculocutaneous
• Ulnar
What is the brachial plexus?
• Brachial plexus is bundle of nerves that exit intervertebral foramen from C5 - T1.
• Travel between anterior & middle scalenes, deep to clavicle & over first rib, deep to pec minor & through axilla to become terminal branches.
• These are all potential areas for impingement.
• Braiding of nerves accounts for all sensory & motor control to entire upper limb.
•Interruption of nerve supply via muscular spasm, trauma, compression, tumours,
What is Thoracic outlet syndrome?
Compression/interruption of brachial plexus, subclavian artery, & subclavian vein.
What are symptoms of Thoracic outlet syndrome?
• paresthesia (ie. numbness, tingling etc) of entire upper limb
• bluish discoloration of affected arm
• arm fatigue during activity
• weak pulse or lack of pulse
• coldness of arm/hand
• swelling
What are common causes of Thoracic outlet syndrome?
• Cervical ribs
• Pregnancy
• Repetitive strain (especially with overhead activity or sports)
• Postural fault
• Trauma
• Fractures (cervical, clavicular, etc)
• Heavy bags/backpacks
• Shoulder dislocations
• surgery
(Terminal branches of brachial plexus) What is the Median nerve?
• Travels with brachial artery through arm
• Passes into anterior forearm through cubital fossa
• Deep to flexor retinaculum at wrist (via carpal tunnel)
• Provides motor innervation to all muscles in superficial, intermediate & deep layers of anterior forearm EXCEPT, flexor carpi ulnaris & medial half
of flexor digitorum profundus.
• In hand it gives off motor supply to thenar eminence & lateral lumbricals
• Sensory area of supply is lateral palm & lateral 3 ½ digits (thumb, index, middle finger & lateral half of ring finger
What is Median nerve damage?
• Presentation is determined by level of injury
• More proximal injury, more severe impairment
• Injury above or at elbow, would be loss of pronation, & weak wrist flexion.
• May notice ulnar deviation as flexor carpi ulnaris would be unopposed
• Wasting of thenar eminence resulting in loss of opposition
• Inability to flex MCP’s or extend PIP’s & DIP’s (lumbricals)
Typical characteristicof median nerve injury is ___________________________.
Hand of Benediction
What are the structures passing through the carpal tunnel?
• The median nerve
• 4 tendons of FDS
• 4 tendons of FDP
• 1 tendon of FPL
What are causes of Carpal tunnel syndrome?
• Trauma/swelling at wrist
• Diabetes
• Pregnancy
• Tendonitis
• Rheumatoid arthritis
• Wrist fracture
• Positional fault
• Idiopathic
What are common signs and symptoms of Carpal tunnel syndrome?
• Parasthesia (feelings of tingling, numb, burning, shooting, electric etc… associated with interruption of nerve supply) into lateral 3 ½ digits
• Weakness
What is the axillary nerve?
• Travels through quadrangular space of posterior shoulder
• Wraps around surgical neck of humerus
• Provides motor supply to deltoids, teres minor, & long head of triceps brachii
• Sensory innervation to “regimental badge” area, around deltoid tuberosity
Typical causes of Axillary nerve damage includes?
• Inferior shoulder dislocations
• Direct trauma/fracture to proximal humerus
• Improper use of crutches
• Breech births (Erb’s palsy C5, C6 nerve roots)
Typical presentation of axillary nerve damage may include?
• Loss of abduction of shoulder (between 15 - 90 degrees)
• Weakness with flexion, extension & lateral rotation
• Loss of sensation over “regimental badge”
• Flat shoulder deformity
What is the radial nerve?
• Travels through triangular interval
• Spiraling around humerus in radial groove
• Motor innervation to lateral & medial heads of triceps brachii, & superficial & deep compartments of posterior forearm (including brachioradialis &
supinator)
• Sensory supply to posterolateral aspect of arm & posterior forearm as well as posterior hand & lateral 3 ½ digits
Typical presentation of radial nerve damage may include?
• Loss of elbow extension
• Loss of wrist & finger extension (Finger/wrist drop)
• Weak supination
• Numbness in sensory distribution pattern
• “Saturday night palsy”
What is the musculocutaneous nerve?
• Travels through axilla & pierces muscles of anterior arm
• Motor supply to biceps brachii, brachialis, & coracobrachialis
• Sensory innervation to anterolateral forearm
• It presents with frequent irregularities in its pathway
What are muscles innervated by musculocutaneous nerve?
BBC = Biceps, Brachialis, Coracobrachialis
What are motor functions of musculocutaneous nerve?
Flexion of arm at elbow, supination of forearm
What are sensory function of musculocutaneous nerve?
Lareral surface of forearm through antebrachial cutaneous nerve
What is Musculocutaneous nerve damage?
• Nerve may be compressed through hypertrophy of biceps brachii & brachialis, can be trapped between 2 muscles, especially for serious weightlifters or body builders
• Can also be compromised by stretch injuries & dislocations of GH joint, or during surgery
• Will likely observe weakness with elbow flexion & supination &/or sensory loss to anterolateral forearm
What is the ulnar nerve?
• Ulnar nerve is notorious for being largest unprotected nerve in human body.
• Most superficially exposed between olecranon & medial epicondyle. Compression at this point known as “hitting your funny bone”. Because of association to word humorous & arm bone, humerus.
• Provides no motor or sensory supply to arm, as it passes through this region.
• In forearm, innervates flexor carpi ulnaris, medial half of flexor digitorum profundus & remaining muscles of hand which are not supplied by median nerve. (hypothenar eminence, dorsal & palmar interossei, medial 2 lumbricals etc)
• Provides sensory innervation to 5th digit & medial half of 4th digit.
• In forearm ulnar nerve travels between 2 heads of flexor carpi ulnaris & down medial forearm to enter hand superficial to flexor retinaculum & deep to hook of hamate (tunnel of Guyon)
What is Ulnar nerve damage
• Injuries to ulnar nerve are common, d/t its superficial exposure, posterior to medial epicondyle.
• Long haul biking can cause compression at Tunnel of Guyon.
• Severe injury may result in condition called “ulnar claw”.
• Presentation is extension at MCP & flexion of PIP’s & DIP’s.
• In present day, with excessive cell phone use & video games, flexor carpi ulnaris can show high MRT in majority of population, which results in compression of ulnar nerve.
What are nerves of the lower limb?
• Sciatic
• Common peroneal
• Superficial peroneal
• Deep peroneal
• Tibial
• Femoral
• Obturator
What is The lumbar plexus?
• Exits intervertebral foramen from T12 - L4
• Travels through psoas to exit pelvis either deep to inguinal ligament, through greater sciatic notch or through obturator foramen
• Branches of lumbar plexus supply sensory & motor innervation to entire lower limb
• Injuries at spinal level can lead to severe functional impairment including paraplegia & altered gait
What is the sciatic nerve?
• Largest nerve fibre in body is comprised of tibial & common peroneal nerves wrapped in one sheath.
• Exits pelvis through greater sciatic notch, passing deep to piriformis down posterior thigh.
• Gives motor innervation to hamstrings & posterior fibres of adductor magnus. Does’nt have any sensory supply to thigh, but it’s branches do in leg & foot.
• Just above level of popliteal fossa, sciatic nerve branches into tibial & common Peroneal nerves which supply leg & foot with both motor & sensory function.
Sensory innervation of the sciatic nerve (sural nerve)
Formed by branches of common fibular & tibial nerves
Sensory innervation of the sciatic nerve (deep fibular nerve)
Branch of common fibular nerve
Sensory innervation of the sciatic nerve (superficial fibular nerve)
Branch of common fibular nerve
Sensory innervation of the sciatic nerve (superficial fibular nerve medial calcaneal branches)
Branches off tibial nerve
What is Sciatic nerve damage/impingement/compression?
• Interruption to sciatic nerve can lead to severe pain & dysfunction.
• Most often caused by disc herniation, spondylolisthesis, spasm in musculature
(ie. piriformis pain syndrome), or stenosis (narrowing of intervertebral foramen).
• Obesity & pregnancy weight gain can both be possible factors causing “sciatica” d/t additional weight compressing IVD’s & bulging them into nerve roots.
• Forward flexion often increase symptoms, while extension exercises can help alleviate discomfort.
• Pain often described as shooting, burning, or electric patient may have difficulty controlling affected limb.
• Motor dysfunction typically presents with weightbearing on affected side.
What is the tibial nerve?
• Originates just above level of popliteal fossa & travels down posterior leg, into foot through tarsal tunnel (between medial malleolus & calcaneus)
• Gives motor supply to all muscles in superficial & deep posterior crural compartments of leg.
• Gives motor information to layers of sole of foot as well as sensory supply.
What is Tarsal tunnel syndrome?
• Compression of tibial nerve as it passes through tarsal tunnel (between medial malleolus & calcaneus).
• S/S present as numbness, tingling, shooting pain etc into sole of foot.
• Common causes include: RA, prolonged eversion, pes planus, direct trauma, tendonitis etc.
What are the The common, superficial and deep peroneal nerves?
• Only called common peroneal nerve from area where it bifurcates above popliteal fossa, until it wraps around neck of fibula, where it is most superficially exposed.
• Branches into deep peroneal nerve which innervates muscles of anterior compartment of leg, & superficial peroneal nerve which innervates
muscles of lateral compartment of leg.
• Deep peroneal nerve also gives sensory supply to web space between the 1st & 2nd toes on dorsum of foot.
• Superficial peroneal nerve provides sensation to anterolateral leg & majority of dorsum of foot, with above noted exception.
What is the obturator nerve?
• Exits pelvis through obturator foramen.
• Gives motor supply to adductor muscles with exception of pectineus (femoral n) & posterior fibres of adductor magnus (sciatic n).
• Provides sensation to majority of skin on medial aspect of thigh.
• Most commonly injured during abdominal or pelvic surgeries. Can cause loss of sensation on medial thigh & difficulty with gait, d/t lack of
adduction. May be observable abduction & external rotation with damage.
What is the femoral nerve?
• Femoral nerve provides motor information to anterior thigh, including quadriceps, pectineus, sartorius, & iliacus.
• Passes deep to inguinal ligament & through femoral triangle.
• Sensation to anteromedial thigh & medial leg comes from branches of femoral nerve.
• There is branch called lateral femoral cutaneous nerve (LFCN) that has clinical relevance in massage therapy.
What is Meralgia Parasthetica?
• Compression of LFCN as it exits pelvis, deep to inguinal ligament, just medial to ASIS.
• Characterized by burning, sometimes excruciating pain over anterolateral thigh. Some people report feeling of multiple bee stings.
• Populations affected include, pregnant people, police officers, construction workers, former hipsters, & obese.
• Often presents with anterior pelvic tilt.
• Find cause - treat cause.
• During massage, firm pressure often feels better than superficial techniques.
• Hip extension can exacerbate symptoms.
