Orthopaedics Flashcards
Musculocutaneous: Nerve root? Common injury site? Motor supply? Sensory supply?
C5-C7
Injury rare as passes beneath the biceps
Supplies elbow flexion = biceps and brachioradialis
Lateral forearm
Axillary: Nerve root? Common injury site? Motor supply? Sensory supply?
C5-C6 Beneath shoulder joint and wraps around humeral head. Injured in: Fracture of surgical neck Anterior dislocation Crutch palsy
Deltoid and teres minor
Lateral shoulder
Radial: Nerve root? Common injury site? Motor supply? Sensory supply?
C5-T1 Travels down spiral groove of humerus, then passes anterior to lateral epicondyle Injury: Fracture to humerus mid-shaft Anterior cubital fossa trauma Tight plaster
Motor = posterior compartment of the forearm = extensions:
Anconeus = extends elbow
Extensor carpi longs and brevis = extend and abduct wrist
Extensor carpi ulnari = Extend and adduct wrist
Extension of fingers
Numbness of skin over the posterior forearm and dorsal thumb and first 2.5 fingers (not tips)
Median: Nerve root? Common injury site? Motor supply? Sensory supply?
C5-T1 Runs medially down posterior arm, into anterior cubital fossa via two heads of pronator teres. Then through anterior forearm Injury: Supracondylar fracture of humerus Trauma to antecubital fossa Deep wrist lacerations Carpal tunnel
motor = anterior forearm = Wrist and finger flexion
Flexor carpi radialis = Flex and abduct wrist
Palmaris longus = wrist flexion
FDS = flex fingers at PIP
Lateral 2 FDP = flex index/middle at DIP
Flexor polices longus = Flex thumbs at IPJ
LOAF: Lateral 2 lumbrical = Flex at MCPJs Opponens pollicis = oppose thumb Abbductor pollicis brevis = Abduct thumb Flexor pollicis brevis = Flex thumb at MPCJ
Sensory = Palmar aspect of thumb and first 2.5 fingers
Ulnar: Nerve root? Common injury site? Motor supply? Sensory supply?
C8-T1
Passes behind medial epicondyle of humerus
Travels through the anterior compartment beneath Flexor carpi ulnaris and enters hand via Guyon’s canal
Injury:
Supracondylar fracture
Trauma to medial epicondyle
Wrist trauma
Motor = flexion and intrinsic hand muscles
Flexor carpi ulnari = Flex and adduct wrist
medial 2 FDP = flex at DIPJ’s
Intrinsic hand = HILA
Hypothenar eminence = oppose flex and abduct little finger
Interossei = finger adduction and abduction
Medial two lumbrical = flex MCPJ’s
Adductor poliicis = adducts thumb
Sensory = Numbness of hypothenar eminence
Lateral cutaneous: Nerve root? Common injury site? Motor supply? Sensory supply?
L2 L3
Travels obliquely to ASIS and passes under the lateral part if inguinal ligament to become cutaneous
Injury = Meralgia paraesthetica, Compression
Supplies skin of lateral thigh
Femoral: Nerve root? Common injury site? Motor supply? Sensory supply?
L2-L4
Leaves pelvis anteriorly under inguinal ligament. Then branches into femoral cutaneous and saphenous
Injury = hip and pelvic fractures
Motor = knee extension and hip flexion
Vastus medialis, intermedius and lateralis
Also supplies sartorial, illiacus, rectus femurs and pectinous
Sensory = skin over medial thigh and saphenous = medial calf
Obturator: Nerve root? Common injury site? Motor supply? Sensory supply?
L2-L4
Passes through obturator foramen to reach medial thigh
Injury = anterior hip dislocation
Motor = Hip adductors
Adductor brevis and longus
Obturator externus
Gracillis
Sensory = skin of medial thigh
Superior gluteal: Nerve root? Common injury site? Motor supply? Sensory supply?
L4-S1
Leaves pelvis above the piriformis
Injury = anterior approach during hip replacement
motor = hip abduction
Gluteus medius and minimus, and tensor fascia lata
Inferior gluteal: Nerve root? Common injury site? Motor supply? Sensory supply?
L5-S2
Leaves pelvis below piriformis
Injury = posterior hip approach
Supplies gluteus maximus = Hip extension
Sciatic: Nerve root? Common injury site? Motor supply? Sensory supply?
L4-S3
Travels deep to hamstrings and divides above knee into common peroneal and tibial nerves
Tibial nerve lies in popliteal fossa and continues posteriorly between muscles of calf = deep and well protected
Common perineal travels with biceps femoris laterally where it passes around neck of fibula
Injury:
Misplaces gluteal injection
Posterior hip approach
Peroneal = Sit cross legged or trauma to posterior knee
Motor:
Sciatic = Hamstrings and adductor magnus
Tibial = Gastrocnemius, soleus and plantar flexors = flexor hallucis longus and digitorum longus, tibialis posterior
Common peroneal = Short head of biceps femoris
Superficial = Peroneus longus and brevis = evertors
Deep = Tibialis anterior, extensor hallucis longus, extensor digitorum lomgus/brevis = dorsiflexors
Sensory:
Peroneal = lateral leg and dorsum of foot
Tibial = lateral ankle and foot
How does L3 or a L4nerve root compression present?
Sensory loss over anterior thigh
Weak quads
Reduced knee reflex
Positive femoral stretch gets
L5 nerve root compression?
Sensory loss of dorsum of foot
Weakness in foot and big toe dorsiflexion
Reflexes intact
Positive sciatic stretch test
S1 root compression?
Sensory loss on posterolateral aspect of the leg
Weakness in plantar flexion
Reduced ankle reflex
Positive sciatic stretch test
