Common sites of peripheral nerve entrapmentcompression Common peripheral

Common sites of peripheral nerve entrapment/compression

Common peripheral entrapment/compression neuropathies - UE Axillary nerve: 1. glenohumeral dislocation 2. in quadrangular space Radial nerve: 1. in axilla (Crutch/Sat. Night palsy) 2. triangular space 3. spiral groove of the humerus 4. supinator syndrome Median nerve: 1. carpal tunnel syndrome 2. pronator teres syndrome Ulnar nerve: 1. medial epicondyle/cubital tunnel 2. tunnel of Guyon Musculocutaneous nerve: 1. in coracobrachialis

Common peripheral entrapment/compression neuropathies - LE 1. Lateral femoral cutaneous nerve – under inguinal ligament (meralgia paresthetica) 2. Sciatic nerve – in piriformis (Piriformis syndrome) 3. Common peroneal nerve – at fibular neck 4. Tibial nerve – at medial ankle (Tarsal tunnel syndrome)

Median nerve entrapment/compression neuropathy 1. Pronator teres syndrome 2. Carpal tunnel syndrome

Median nerve entrapment/compression neuropathy 1. pronator teres syndrome Motor weakness: *forearm muscles *flexor carpi radialis (FCR) *flexor digitorum profundus (2 nd & 3 rd fingers) – DIP jt *thenar eminence muscles *opponens pollicis *abductor pollicis brevis Sensory alteration in territories of both palmar cutaneous branches and digital sensory branches

Median nerve sensory territory

Median nerve entrapment/compression neuropathy 2. carpal tunnel syndrome Motor: Forearm muscles - SPARED (FCR, FDP -2 nd/3 rd DIP jts) Thenar muscle weakness *opponens pollicis *abductor pollicis brevis Sensation: *palmar cutaneous branch - SPARED *digital branches affected

Ulnar nerve entrapment/compression neuropathy 1. Medial epicondyle/cubital tunnel 2. Tunnel of Guyon

Ulnar nerve entrapment/compression neuropathy 1. medial epicondylar groove / Cubital tunnel Motor – weakness: forearm muscles *Flexor Carpi Ulnaris (FCU) *Flexor Digitorum Profundus (4 th-5 th digits, DIP jt) hypothenar eminence muscles *opponens digiti minimi interossei (finger AD/ABductors) Sensory alteration in both ventral & dorsal branches

Ulnar nerve entrapment/compression neuropathy 2. Tunnel of Guyon Motor: forearm muscles - SPARED *Flexor Carpi Ulnaris (FCU) *Flexor Digitorum Profundus (4 th-5 th digits, DIP jt Weakness of: *hypothenar eminence muscles *opponens digiti minimi *interossei (finger AD/ABductors) Sensory alteration in ventral branch Sensation in DORSAL branch SPARED

Radial nerve entrapment/compression neuropathy 1. Axilla “Crutch palsy” “Sat. Night palsy” 2. Triangular space 3. Spiral groove of the humerus 4. Supinator syndrome

Radial nerve entrapment/compression neuropathy 1. crutch palsy Weakness from triceps down *triceps *brachioradialis *supinator *wrist extensors *finger extensors

Radial nerve entrapment/compression neuropathy 3. spiral groove of the humerus (“lover’s palsy”, “honeymooner’s palsy”) *triceps spared *weakness from brachioradialis down: *brachioradialis *supinator *wrist extensors *finger extensors

Radial nerve entrapment/compression neuropathy 2. triangular space Weakness from triceps down: *triceps (may be partially spared) *brachioradialis *supinator *wrist extensors *finger extensors

Radial nerve entrapment/compression neuropathy 4. Supinator syndrome (posterior interosseous branch of the radial nerve) *triceps, brachioradialis, supinator spared *wrist extensors may be partially spared *weakness of: *wrist extensors (partial) *finger extensors

Sensory loss in radial nerve compression lesions – cont. Proximal compression (axilla, triangular space) will affect all the sensory branches. Sensory loss in the arm & forearm, will often be masked due to the significant overlap of the sensory territories of adjacent nerves, and diminished sensation may only be discovered in the dorsal web of the hand (superficial radial nerve territory). Compression in the spiral groove of the humerus will affect the posterior antebrachial cutanteous nerve, and the superficial radial nerve. Again, sensory loss may only be discovered in the dorsal web of the hand. Since the superficial radial branch comes off proximal to the supinator muscle, entrapment will spare all the sensory branches of the radial nerve, and there should be no sensory loss.

Sensory loss in radial nerve compression lesions The radial nerve gives off several sensory branches as it travels down the arm: 1. 2. 3. Posterior brachial cutaneous nerve Posterior antebrachial cutaneous nerve Superficial radial nerve

Axillary nerve entrapment/compression neuropathy (quadrangular space, GH dislocation) Motor weakness: *deltoid (abduction) *teres minor (ext. rotation) Sensory alteration: *lateral aspect of proximal arm

Musculocutaneous nerve entrapment/compression neuropathy compression in the coracobrachialis Motor weakness: *biceps brachii Sensory alteration: *lateral forearm (ant & post)