% Lesiones en Bienes de Interés Cultural
ANEJO 1 FICHAS DE RECONOCIMIENTO
Upon suspecting median nerve palsy, rule out ulnar and brachial neuritis Median nerve palsy
Motor
Wasted thenar eminence
Thumb is externally rotated into the plane of the thumb rather than perpendicular Pen-touch test (for abductor pollicis brevis)
Oschner clasping test (flexor digitorum superficialis)
Flexion of the terminal digit of the thumb (flexor pollicis longus)
Flexion of the terminal digit of the index finger (flexor digitorum profundus) Sensory
Test for reduced sensation in the lateral 31/2 fingers as well as thenar eminence.
Exclude ulnar and radial nerve palsy Aetiology
Tinel‟s sign Look for RA hands
Look at the wrist and forearm, elbow, arm and axilla for scars.
Test for function
Rule out Myxedema and acromegaly Presentation
Sir, this patient has an isolated unilateral right median nerve palsy with wasting of the right thenar eminence associated with an externally rotated thumb. There is weakness of abduction of the thumb as demonstrated by the pen touch test associated with reduced sensation to pinprick in the right lateral 3 1/2 fingers. Oschner‟s clasping test is negative and flexion of the terminal phalanx of the thumb and index fingers are preserved, indicating that the level of the lesion is at the wrist.
There is no ulna or radial nerve palsies.
In terms of aetiology, there is also no evidence of RA of the hands and patient does not have features of hypothyroidism or acromegaly. Tinel‟s sign is negative and there are no scars noted on the right upper limb.
Both fine and coarse motor functions are intact.
In summary, this patient has a right median nerve palsy at the level of the wrist. Possible aetiologies includes surgical causes such as compression, trauma or surgery or medical causes such as mononeuritis multiples, infection, inflammatory and ischaemic causes.
98 Questions
What is the course and branches of the median nerve?
It supplies all the muscles of the forearm except the flexor carpi ulnaris and the ulna half of the flexor digitorum profundus and LOAF (lateral 2 lumbricals, opponens pollicis, abductor pollicis brevis and flexor pollicis brevis)
Formed by lateral(C5-7) and medial(C8,T1) cords of the brachial plexus
Enters the arm closely related to the brachial artery with no branches above the elbow Enters the forearm lateral to the brachialis tendon and in between the pronator teres.
Gives off the anterior interosseous nerve
Above the wrist, gives off the palmar cutaneous branch
Enters the carpal tunnel and supplies LOAF and sensory branch to the lateral 3 ½ fingers.
Branches
Forearm – flexor carpi radialis, flexor digitorum superficialis (flexion of fingers at the PIPJ), pronator teres
AIN – Flexor pollicis longus (flexion of the DIPJ thumb), flexor digitorum profundus of the lateral 2 fingers (flexion of at the DIPJ), pronator quadratus
Palmar cutaneous (to the thenar eminence)
Terminal motor (LOAF) (NB for F for flexion at the MCPJ thumb) What are the various levels of lesions and the clinical correlation?
Wrist
Wasting of thenar, ext rotated thumb, pen touch test positive; sensory loss of the lateral 3 ½ fingers Cubital fossa
Above plus
Oschner clasping test positive and failure of flexing the terminal digits of the thumb and index finger Arm and axilla (same as cubital fossa)
(For forearm, depends where the lesion is eg AIN syndrome will affect flexor digitorum profundus and flexor pollicis longus only)
What are the causes?
Trauma Surgical Compression
Mononeuritis multiplex Infection – Leprosy Inflammatory – CIDP Ischaemic - Vasculitis
Causes of Carpal tunnel syndrome Idiopathic
Pregnancy, OCPs
Endocrine – Hypothyroidism, Acromegaly Hands – RA, gout, TB tenosynovitis, OA of carpus
Amyloidosis, CRF, sarcoidosis
What are the tests to demonstrate a median nerve palsy?
Tinel‟s sign (percussion)
Phalen‟s test (flexion at the wrist for 60 s) Hyperextension of the wrist (for 60 s)
Tourniquet test (sphygmomanometer for more than 2 mins above systolic)
Luthy‟s sign – Skinfold does not close tightly around a bottle or cup; secondary to thumb abduction paresis Durkan‟s test – apply direct pressure over the carpal tunnel
What are the other areas of nerve compression?
Median nerve (CTS) Ulna nerve (elbow tunnel)
Radial nerve (spiral or humeral groove)
Meralgia paraesthetica (lateral cut nerve of the thigh at the ing lig) Common peroneal nerve (head of the fibula)
Posterior tibial nerve (Tarsal tunnel syndrome)
Plantar nerves of the 3rd/4th toes (Morton‟s metatarsalgia) How would you investigate?
o Blood Ix o Imaging – X-rays
o Nerve conduction test demonstrating slow sensory conduction across the transverse carpal ligament.
How would you manage?
Education OT and wrist splint
Medications – treatment of underlying disease, withdrawing OCPs, IA steroid Surgical decompression
What is the prognosis?
o Neuropraxia with no disruption to the sheath or the axon Recovery complete and rapid (weeks)
o Axonotmesis with disruption of the axon but an intact Schwann sheath Recovery complete but slower (1mm/day)
o Neuronotmesis
Recovery is incomplete
100 45. Ulnar Nerve Palsy
Examination
Rule out median, radial and brachial neuritis Inspecting
Wasting of the muscles of the hands, hypothenar eminence and partial clawing of the 4th and 5th fingers, sparing of the thenar eminence, ulnar paradox
Proceed to tests for finger abduction and Froment‟s sign (weakness of the adduction of the thumb)
Test finger flexion of the 5th finger for flexor digitorum profundus involvement; test for wrist flexion at the ulna side and look for the tendon of the flexor carpi ulnaris
Rule out median nerve (thenar eminence and ext rot thumb, pen touch test and Oschner clasping test) and radial nerve Sensory testing in the medial 1 ½ fingers; test T1 sensory loss
Examine the wrist and elbows (feel for thickened nerve, wide carrying angle)) Function
Thickened nerve (cf with Pb for radial and Acromeg etc for median) Presentation
Sir, this patient has got a isolated left ulnar palsy as evidenced by a left ulnar claw hand with wasting of the small muscles of the hands with dorsal guttering as well as wasting of the hypothenar eminence. There is sparing of the thenar eminence.
There is weakness of finger abduction and Froment‟s sign is positive. There is preservation of the flexion of the DIPJ of the 4th and 5th fingers; when the hand is flexed to the ulna side against resistance, the tendon of the flexor carpi ulnaris is palpable. This is associated with reduced sensation to pinprick in the medial 1/1/2 fingers. There are no associated median or radial nerve palsies and T1 involvement.
In terms of aetiology, there is a scar at the wrist associated with a marked ulnar claw hand, demonstrating the ulna paradox. I did not find any signs to suggest leprosy such as thickened nerves, hypopigmentation patches or finger resorption.
Both coarse and fine motor function of the hand is preserved.
In summary, this patient has a left ulna claw hand due to a traumatic injury to the left wrist.
Questions
What is the anatomical course of the ulnar nerve?
It provides motor to all muscles of the hands except the LOAF; flexor carpi ulnaris and flexor digitorum profundus to the 4th and 5th fingers.
Sensory to the ulna 1 ½ fingers
Begins from the medial cord of the brachial plexus (C8 and T1) No branches in the arm
Enters the forearm via the cubital tunnel (medial epicondyle and the olecranon process) and motor supply to the flexor carpi ulnaris and ulna half of the flexor digitorum profundus
It gives off a sensory branch just above the wrist and enters Guyon‟s canal and supplies the sensory medial 1½ fingers and hypothenar as well as motor to all intrinsic muscles of the hands except LOAF.
What is the level of lesions and its clinical correlation?
Wrist – Hypothenar eminence wasting, Froment‟s positive, weakness of finger abduction, pronounced claw and loss of sensation
Elbow – less pronounced claw and loss of terminal flexion of the DIPJ and loss of flexor carpi ulnaris tendon on ulna flexion of the wrist
How do you differentiate ulnar nerve palsy vs a T1 lesion?
Motor – wasting of the thenar eminence in addition for T1 Sensory – loss in T1 dermatomal distribution
What is the ulna claw hand?
It refers to the hyperextension of the 4th and 5th MCPJ associated with flexion of the IPJs of the 4th and 5th fingers as a result of ulnar nerve palsy. It is due to the unopposed long extensors of the 4th and 5th fingers in contrast to the IF and MF which are counteracted by the lumbricals which are served by the median nerve.
What is the ulnar paradox?
It means that the ulnar claw deformity is more pronounced for lesions distally e.g. at the wrist as compared to a more proximal lesion e.g. at the elbow. This is because a more proximal lesion at the elbow also causes weakness of the ulnar half of the flexor digitorum profundus, resulting in less flexion of the IPJs of the 4th and 5th fingers.
What is Froment‟s sign?
Patient is asked to grasp a piece of paper between the thumbs and the lateral aspect of the index finger. The affected thumb will flex as the adductor pollicis muscles are weak. (Patient is trying to compensate by using the flexor pollicis longus supplied by median nerve)
What are the causes of an ulnar nerve palsy?
Compression or entrapment (Cubital tunnel at the elbow and Guyon‟s canal at the wrist) Trauma (Fractures or dislocation – cubitus valgus leads to tardive ulnar nerve palsy) Surgical
Mononeuritis multiplex Infection – leprosy Ischaemia – Vasculitis Inflammatory - CIDP How would you investigate?
Blood Ix to rule out DM if no obvious cause
X-rays of the elbow and wrist (both must be done to rule out double crush syndrome) (KIV C-spine and CXR)
EMG(axonal degeneration for chronic) and NCT(motor and sensory conduction velocities useful for recent entrapment as well as chronic) to locate level and monitor
How would you manage?
Education and avoidance of resting on elbow OT, PT
Medical – NSAIDs and Vit B6
Surgical decompression with anterior transposition of the nerve
NB: LOAF – lateral 2 lumbricals, opponens pollicis, abductor pollicis brevis and flexor pollicis brevis
102 46. Wasted Hands
Unilateral vs Bilateral (think of levels!) Unilateral
Think of (no myopathy, got brachial plexus) Peripheral nerve (median, ulnar or combined)
Mononeuropathy vs peripheral neuropathy (asymmetric involvement) Brachial plexus (trauma, tumor, radiation, Cx rib)
C8-T1 root lesions (Cx spondylosis) Anterior Horn Cell (Poliomyelitis) Cervical cord
Proceed as:
Long case – as per protocol, check also neck and chest Short case
On inspection, unilateral wasted hands noted Neurological hand screen
Examine for ulnar and median nerve palsies.
Check for sensory for nerve vs root (peripheral nerve vs brachial plexus) and no loss (ie anterior horn cell) Note sensory for ulnar, median and radial
Note sensory of peripheral neuropathy Note dermatomal sensory
Feel for thickened nerves, look for hypoaesthetic macules, fasciculations Look for scars in the axilla and neck (neck pain, tenderness), Cx rib Check function
Requests
Palpate for cervical rib and features of Pancoast‟s tumor (dullness to percussion, Horner‟s syndrome, hoarseness voice)
Check for winging of scapula (for brachial plexus involvement) If brachial plexus
Upper vs lower (wasting of muscles of hands) vs complete Surgical(Cx rib, Pancoast) vs medical cause(brachial neuritis) Test for proximal involvement
Serratus anterior (winging of scapula on pushing against wall) ie C5,6,7 Supraspinatus (abduction of UL from hands by your side position) C5 Infraspinatus (elbow flexed and push backwards) C5
Rhomboids (hand on hip and push backwards) C4,5,6 Reflexes (inverted supinator jerk)
Bilateral Think of
Rule out the obvious (hand screen) RA, gouty hands
Dystrophia myotonica
Levels (got myopathy, maybe brachial plexus if bilateral Cx ribs) Distal myopathy (reflexes normal; rare), dystrophia myotonica Peripheral nerve lesions
Combined CTS (see median nerve palsy) Combined ulnar and median nerve
Leprosy (resorption, hypoaesthetic macule and thickened nerve) HMSN (look at the feet for pes cavus deformities, thickened nerves) Peripheral motor neuropathy
(Not likely to be brachial plexus unless bilateral Cx ribs) Nerve roots
Cervical spondylosis (inverted supinator jerk, increased jerks for high cervical cord lesions) Anterior Horn cell (no sensory loss)
MND (fasciculations) Poliomyelitis SMA Spinal cord lesions
Intramedullary (Syringomyelia – dissociated sensory loss) Extramedullary
Request
LL – spastic paraparesis ( if suspect Cx cord, MND)
Lower cranial nerve (bulbar palsy – if suspect MND or syringomyelia) Proceed as
Long case
Proceed as per normal
Examine or request to examine the neck (pain tenderness and pain on neck movements), chest, CNs and LLs accordingly
Short case
Neurological hand screen
Median and ulnar nerve testing, and wrist drop( because this is also weak in C8 root lesions) Sensory – peripheral nerve vs neuropathy vs root
Check the elbows for thickened nerves
Look for fasciculations (peripheral nerve, neuropathy, MND), hypoaesthetic macules Inspect the neck
Quick glance at the face (NG tube – bulbar palsy, LLs – HMSN) Check function
Request for reflexes, percussion myotonia if deemed appropriate (if suspect Cx cord lesion or dystrophia myotonica)
104 Questions
What are the levels and causes?
Disuse atrophy (RA hands)
Myopathy (distal myopathies or dystrophia myotonica – usually forearms more affected) Peripheral neuropathy - motor (see causes in Neurology segment)
Mononeuropathy
Surgical, trauma or compression
Mononeuritis multiplex, infection, inflammatory and ischaemic Brachial Plexus
Surgical, trauma compression (Pancoast‟s, Cx rib) Brachial neuritis
Nerve root (Disc prolapse) Anterior Horn cell
MND, poliomyelitis, SMA Spinal cord
Intramedullary Extramedullary How would you Ix?
Blood Ix according to causes as above Imaging – X-rays, CT or MRI of spine NCT/EMG
What are the causes of a claw hand?
Partial claw
Ulnar nerve palsy (See Ulnar nerve) True Claw
Non-neurological RA
Severe Volkmann‟s ischaemic contracture Neurological (5)
Combined median and ulnar nerve
Leprosy (reflexes present. Pain loss, thickened nerves)
Lower brachial plexus ( C7-T1, selective loss of reflexes, pain loss) Poliomyelitis (reflexes selective, pain intact)
Syringomyelia (reflexes absent, pain loss)
47. Syringomyelia