Carry out a neurological examination of this patient's upper limbs.
· Repeated trivial trauma to the elbow - the patient feels the 'funny bone'.
· Patient may be immobilized in the orthopaedic ward and use elbows to shuffle in bed.
· History of fracture of the upper arm in childhood (supracondylar fracture of humerus in childhood has an insidious course and
can result in acute ulnar nerve palsy 20-30 years later - tardy ulnar palsy).
· Generalized wasting of the small muscles of the hand.
· There may be features of ulnar claw hand, i.e. hyperextension at the metacarpo-phalangeal joints and flexion at the
interphalangeal joints of the fourth and fifth fingers.
· There is weakness of movement of the fingers, except that of the thenar eminence.
· There is sensory loss over the medial one and half fingers.
Proceed as follows:
· Examine the elbow for scars and signs of osteoarthrosis.
· Comment on the large carrying angle at the elbow, particularly in women (repeated extension and flexion of the arm can result
in damage to the olecranon and consequently the ulnar nerve).
This patient has wasting of the small muscles of the hand and claw hand with sensory loss over the medial one and half fingers
(lesion) due to ulnar nerve palsy caused by trauma (aetiology). She is unable to button her clothes (functional status).
What are the muscles supplied by the ulnar nerve?
The ulnar nerve is derived from the eighth cervical and first thoracic spinal nerves. It gives no branches above the elbow and
In the forearm:
· Flexor carpi ulnaris.
· Medial half of the flexor digitorum profundus.
In the hand:
· Movers of the little finger - abductor digiti minimi, flexor digiti minimi and opponens digiti minimi.
· Adductor pollicis (oblique and transverse heads).
· Dorsal and palmar interossei.
· Third and fourth lumbricals.
· Palmaris brevis.
· Inner head of flexor pollicis brevis.
How would you differentiate between a lesion above the cubital fossa and a lesion at the wrist?
· In lesions above the cubital fossa the flexor carpi ulnaris is involved.
· In lesions at the wrist, the adductor pollicis is involved.
How would you test the flexor carpi ulnaris?
· Ask the patient to keep her hand flat on a table with the palm facing upwards and then ask her to perform flexion and ulnar
deviation at the wrist.
How would you test the adductor pollicis?
Ask the patient to grip a folded newspaper between the thumb and index finger of each hand so that the thumbs are uppermost this
causes the adductor to contract. When the muscle is paralysed, the thumb is incapable of adequate adduction and becomes flexed
at the interphalangeal joint due to contraction of the flexor pollicis longus (innervated by the median nerve). This is known as
What is ulnar paradox?
The higher the lesion in the upper limb, the lesser is the deformity. A lesion at or above the elbow causes paralysis of the ulnar half
of the flexor digitorum profundus, interossei and lumbricals. Thus, the action of the paralysed profundus is not unopposed by the
interossei and lumbricals; as a result the ring and little fingers are not flexed and hence there is no claw, whereas a lesion at the
wrist causes an ulnar claw hand.
What causes the ulnar claw hand?
A lesion of the ulnar nerve at the wrist. The little and ring fingers are flexed at the
interphalangeal joints and hyperextended at the metacarpophalangeal joints. The index and middle fingers are less affected as the
first and second lumbricals are supplied by the median nerve.
What are the causes of claw hand?
True claw hand is seen in the following conditions:
· Advanced rheumatoid arthritis.
· Lesions of both the median and ulnar nerves, as in leprosy.
· Lesions of the medial cord of the brachial plexus.
· Anterior poliomyelitis.
· Amyotrophic lateral sclerosis.
· Klumpke's paralysis (lower brachial plexus, C7-8 involvement).
· Severe Volkmann's ischaemic contracture.
How is the ulnar nerve affected at the wrist?
The deep branch of the ulnar nerve is motor and may be compressed in Guyon's canal, which runs between the pisiform and hook of
the hamate. This results in wasting and weakness of the interossei, particularly the first and the adductor pollicis, but sensation is
spared. Also the hypothenar muscles are usually spared, although the third and fourth lumbricals may be affected. The nerve may
be com-pressed in Guyon's canal by a ganglion, neuroma or repeated trauma. Surgical exposure of the nerve may be necessary
when there is no history of trauma.
What is the most common cause of an ulnar nerve lesion at the elbow?
It is due to compression of the nerve by the fibrous arch of the flexor carpi ulnaris (the cubital tunnel) which arises as two heads from
the medial epicondyle and the olecranon.
What do you understand by the term 'tardy ulnar nerve palsy'?
This occurs as a result of injuries or arthritic changes at the elbow causing a delayed or slowly progressive involvement of the ulnar
How would you rapidly exclude an injury to a major nerve in the arm ?
· Radial nerve: test for wrist-drop.
· Ulnar nerve: test for Froment's sign (see above).
· Median nerve: Ochsner's clasping test.
Jules Froment (1876-1946), Professor of Clinical Medicine, Lyons, France.
A.J. Ochsner (b. 1896), a US surgeon, also investigated the role of tobacco in lung cancer.
Augusta Dejerine-Klumpke (1859-1927), a French neurologist, was the first woman to receive the title 'Internes des Hbpitaux' in
R. von Volkmann (1830-1889), Professor of Surgery in Halle, Germany.