Clinical aspect of upper extremity

 

Surface anatomy

1 pectoralis major 2 floor of axilla

1 anatomical snuffbox 2 cubital fossa

1 triceps brachii 2 olecranon  3 flexor carpi ulnaris

 1 jugular notch 2 clavicle 3 acromion 4 nipple

1 inferior angle of scapula 3 medial epicondyle of humerus 4 lateral epicondyle of humerus 5 olecranon 

 1 brachioradialis 2 extensor carpi radialis brevis 3 extensor carpi radialis longus 4 biceps bachii 5 deltoid 6 pectoralis major 7 external oblique muscle of abdomen 8 trapezius

 

 

1 medial epicondyle of humerus 2 flexor carpi ulnaris

1 tendons of extensor digitorum 2 anatomical snuffbox 3 styloid process of ulna

 1 thenar eminence 2 hypothenar eminence

 

Clinical aspects of superficial upper extremity

Important structures in the upper extremity includes muscles, bones, and vessels, joints and nerves. We shall follows al the above sequence in dealing with abnormalities of the upper extremity.

 

Clinical examination.

In performing any clinical examination, always remember that inspection comes first, followed by palpation and hen percussion and finally auscultation.

Inspection:

Observations of surface myology is part of inspection. It is important to recognise muscle wasting, and deformities such as in Dupuytren’s contracture. Muscle disability can arise as a result of loss of nerve supply, blood supply or rupture due to trauma. It is important to remember the different types of nerves and their nerve roots in the identification of muscle paralysis.

In testing the power of individual muscles the Medical Research Council (Britain) recommends that the following gradings should be followed

 

0        active contraction

1        visible contraction without active movement

2        movement which is possible with gravity eliminated

3        movement which is possible against gravity

4        movement which is possible against gravity plus resistance but which is weaker than normal

5        normal power.

When muscle weakness is suspected due to nerve damage, in the process of testing, there is the need to perform a thorough neurological examination which involves the study and examination of the dermatomes supplied by the nerve roots that provide motor supply to the muscles under study.

  • To test the flexors of the fingers (flexor digitorum profundus and flexor digitorum superficialis) the fingers are flexed against resistance etc.

  • The lumbricals can be tested by causing flexion at the metacarpophalangeal joints and extension at the interphalangeal joint- ie the writing position.

  • The interossei are tested by asking for adduction or abduction of the fingers against resistance. Remember that all the muscles of the fingers are supplied by the ulnar nerve except LOAF – lateral two lumbricals, opponens pollicis brevis, abductor pollicis brevis, flexor pollicis brevis all of the thenar eminence. To test therefore the function of the median nerve in the hand m it is important to test the action of the thenar muscles.

  • The pen touching test helps to identify the paralysis of the abductor pollicis brevis, a thenar muscle. The hand is laid on the table and a pen is held a little above the thumb. With the thumb touching the ground, the subject is asked to raise the thumb in order to touch the pen. If he cannot do this, it means the abductor muscle is paralysed and the lesion is probably from the median nerve at the wrist.

  • The test of the function of the ulnar nerve at the hand is usually the function of the adductor pollicis which lies in its own compartment in the hand called the adductor pollicis compartment. This is performed by the paper handling test. When a newspaper is held with the thumb upwards, the paralysed thumb does not adduct with the rest of the fingers since the adductor muscle is paralysed. But a trick action o f the flexor pollicis longus flexes the thumb and in doing so prominently flexes the interphalangeal joint of the thumb and its easily recognised as Froment’s sign positive.

  • Extensor action on the fingers can be tested by asking the subject to extend the fingers against resistance.

  • Rupture of the tendons of insertion of the flexors and the extensors can occur. For example rupture of the collateral slip of the dorsal digital expansion which is inserted into the terminal phalanx, is called baseball or mallet finger. Rupture of the flexor tendons of the fingers may also arise –e.g. rupture of the flexor digitorum superficialis. It is commoner to have knife cut of the tendons. Rupture or division of both tendons cause loss of ability to flex the two interphalangeal joints while the rupture of only the profundus tendon affects the distal interphalangeal joint. Rupture of the superficialis alone (not common) only weakenes the act of flexion since the profundus can perform the action of flexion alone.

  • Testing the wrist joint range of movement involves the technique of extension to 70o and flexion to 80o in the normal range. If pain occurs in this range or if there is inability to make the range, then the extensors of the carpus (extensor carpi radialis longus and brevis, and other extensors of the wrist that cross the joint must be sought for. It also includes the technique of testing for the range of ulnar and radial deviations performed by the agencies of the extensor carpi radialis and the flexor carpi radialis (radial deviation) and the extensor carpi ulnaris and the flexor carpi ulnaris (for ulnar deviation).

  • Generally the test of muscle functions in the forearm may be performed in unison with the functional tests in the fingers. But also the test of pronation and supination gives a fast indication as to the possibility of lesion in the elbow or forearm or the wrist joint.

  • When the median nerve is damaged in the elbow around the cubital fossa, the Ochsner’s test can be performed. In this test, the patient is aked to clasps both hands. The index finger fails to flex if the test is positive because the flexor tendons to the index finger are weak.

  • In testing for the functions of the muscle of the elbow and the upper arm, the range of movement of the elbow joint must be taken into consideration. Normal range of flexion is about 30o and the normal range of extension is 150o. It is also important to note the equilateral triangle formed by the two epicondyles of the humerus and the olecranon at the posterior aspect of the elbow. If the points are not equidistant or palpable, then a fracture dislocation or other lesions may be suspected.

  • The muscles of the pectoral girdle and the shoulder can be tested by the range of movements affected by the shoulder joint. They are abduction, adduction, external rotation and internal rotation. Abduction and adduction will normally test the action of the pectoral muscle and the deltoid. Rotation will test the action of the rotator cuff muscles.

  • Raised arm test can be used in determining the integrity of the shoulder arc. For example when a patient is asked to raise his two arms up with the palm touching above, if normal he experiences no pain. If abnormal, then action causes pain at the range of 60o-120o and this may be caused by rupture of supraspinatus tendon and the condition is then termed the painful arc syndrome.

 

Miscellaneous conditions of upper extremity

  • Erbs-Duchenne paralysis is caused by the affectation of the nerve roots C5 and 6 resulting from excess displacement of the head and neck from the shoulder causing the stretching of the roots or a fall on the shoulder or as is often the case, forcible depression of the shoulder during delivery. The affected limb is placed in a characteristic waiter’s tip position due to failure or weakness of the elbow and shoulder musculature.

  • Klumpke’s paralysis occurs as a result of a lesion affecting nerve roots C8 and T1. It may occur as a result of a pull on the upper limb towards the head as in forcible delivery of a new born or any other form of injury. It then leads to the paralysis of all the intrinsic musculature of the hand and causes claw hand deformity.

  • Axillary nerve palsy is caused by damage to the axillary nerve in dislocation of the shoulder or fracture of he neck of the humerus. This causes atrophy of he deltoid muscle and abduction of he arm in the shoulder joint is impossible unless the patient helps himself by applying the other hand.

  • Long thoracic nerve palsy. This is caused by damage to the long thoracic nerve that supplies the serratus anterior. The damage may be caused accidentally during mastectomy or weight lifting. A push against a wall with the hand will cause the winging of the scapula on the affected side  - winged scapula.

  • Thoracodorsal nerve palsy may arise as a result of the damage to the nerve during radical mastectomy. All movements can be performed on the shoulder joint in this condition except a forcible adduction of the shoulder joint.

  • Radial nerve palsy is caused by the damage to the radial nerve- usually in the axilla. It may be caused by the extensive use of axillary crutches or in a condition known as Sarturday night paralysis in which a drunken man has slept on the chair with the base of the axilla of the affected limb against the handle of a chair for a considerable period of time.

  • Median nerve palsy. The median nerve can be commonly damaged at the wrist or at the cubital fossa leading to median nerve palsy . WE had mentioned earlier the Ochsner’s test which is expected to be positive in this condition. Also the pen-touching test, in which the thumb cannot be abducted to a pen placed above it as a result of the paralysis of the abductor pollicis brevis. The patient is also unable to pick up a pin with his thumb and index finger because of the paralysis of the opponens pollicis.

 

·                    Ulnar nerve palsy; This is caused by damage to the ulnar nerve at the wrist or ciubital fossa or above the elbow. Froment’s sign is positive- ie the paper holding test to demonstrate the action of the adductor pollicis. The patient also develops the ulnar claw hand deformity

·                   

 

 

  • Painful arc syndrome. We had mentioned this above. Rupture of the supraspinatus tendon which causes loss of abduction of the shoulder joint above 50o may cause this condition.

  • Subacromial bursitis. This is infection and enlargement caused by fluid in the subacromial bursa.

  • Rupture of the biceps brachii may occur as a result of weight-lifting. The biceps forms a diagnostic lump in the middle of the front of the arm.  

  • Elbow tunnel syndrome is caused by the affection of the ulnar nerve in its groove behind the elbow. It causes wasting of muscles supplied by the ulnar nerve to the hypothenar muscles

  • Carpal tunnel syndrome: This is caused by pressure on the median nerve as it crosses the carpal tunnel. It may be due to increased pressure as a result of abscess formation or the increased pressure in the tunnel may be of unknown cause. It causes mainly pain and acroparasthesia of the sensory supply areas of the median nerve.

  • Hand abscesses are usually confined to compartments of the hand unless a generalised cellulitis occurs. It may arise as a result of a tenosynovitis of a finger. If the tenosynovitis affects the little finger then the infection may spread to the ulnar bursa and subsequently to the space of Parona. Infections may also be confined to the thenar space or the hypothenar space, causing a ballooning of the areas affected.

  • Dupuytren’s contracture is a thickening of the palmar aponeurosis leading to flexion deformity in which the ring finger is severely affected.

  • Flexor tendon adhesion is often the sequelae of severe tenosynovitis leading to loss of the ability to flex or extend the fingers because of adhesions in the tendons.

  • Congenital contracture of the little finger may be similar to Dupuytren’s contracture but the thickening of the palmar aponeurosis is not present in this condition.

  • Volkmannn’s ischaemic contracture is caused by injury to the muscle’s blood supply in front of the forearm, caused by a tight application of bandage or plaster of Paris. It may lead to claw hand deformity.

 

Procedures

The most common clinical procedure in the upper limb include radial pulse detection, intravenous injections and blood letting, blood pressure recordings, intrarterial catheterisations, brachial plexus block, intravenous local anesthesia and local anesthetic injections to the digits.

  • Radial pulse can be obtained at the course of the radial artery near the wrist as it lies on the pronator quadratus in the interval between the abductor pollicis brevis and extensor pollicis longus on the lateral side, and the flexor carpi radialis tendon on the medial side. It then passes underneath the tendons of the abductor pollicis longus and the extensor pollicis brevis to enter the anatomical snuff box and disappear from view. At this point of its course in the forearm, the radial artery is most liable to injury by a knife cut stemming from suicide attempt or accident or homicide.

  • The ulnar pulse can also be obtained at similar position (near the wrist) but the artery is placed deeper than the radial artery. In this position it lies at the interval between the flexor digitorum superficialis and the flexor carpi ulnaris.

  • Antecubital venepuncture: The antecubital vein lies in the roof of the cubital fossa forming a communication between the basilic vein and the cephalic vein. It is separated from the content of the cubital fossa, especially at the medial aspect by the bicipital aponeurosis so that accidental puncture of the brachial artery may be less easy. This vein is also amenable to intravenous cut down procedure. Incision is made into the skin and the superficial fascia is identified and dissected to secure the vein. After the vein is secured, a small incision is made in its wall to allow the introduction of the intravenous cannula.

  • Venepuncture of small veins. Routine intravenous needling can be carried out with the use of the numerous tributaries of the dorsal venous arch which forms the cephalic vein. In children where the location of he tributaries may be difficult, a constant metacarpal tributary is found in the 4th metacarpal space between the 4th and 5th metacarpal bones and blind needling of this vein with a scalp vein set may well be rewarding.

  • Blood pressure recording. The brachial artery at the cubital fossa is used for the recording of blood pressure. This artery enters the cubital fossa at the lateral aspect of the median nerve.

Intravenous local anesthesia

  • This procedure is utlilised in surgical manouver of  the upper extremity which do not require a long period of time. A dorsal venous arch tributary or a metacarpal vein is selected for this procedure and the cuff of the blood pressure machine (sphygmomanometer) is utilised to deliver a pressure between the systolic and diastolic figures into the upper arm. By this method, the anesthetic solution remains in the limb since blood can enter the limb but will not be able to come out.

  • Brachial plexus block.  Anesthetic solution is administered at the apex of the axilla, just lateral to the anterior border after the identification of the outer border of the first rib.

  • Arterial punctures. For arterial punctures or catheterisations, the radial artery or brachial artery may be used in the upper extremity. The brachial artery is exposed in the upper extremity by an incision into the roof of the cubital fossa through the skin, superficial fascia and deep fascia, taken care to avoid the veins in the roof. The bicipital aponeurosis is then identified and divided to gain proper visual access to the brachial artery.

  • The radial artery is exposed by an incision into the skin  just a little below the wrist at its lateral side. The superficial and deep fasciae are cleared away and the artery is identified lateral to the flexor carpi radialis where it is secured.

Procedures on the digits

The digits are supplied by arteries and nerves which run along their medial and lateral borders. Injections of local anesthetic solution to deaden the nerves must be applied at the interdigital clefts with needle directed at the lateral and medial aspects of the digits, most especially but also around the circumference of the digits generally. This is the same for the lower extremity.

 

Surface myology of upper extremity

 

 

1 Pectoralis major 2 Rectus abdominis 3 Deltoid 4 Triceps brachii 5 Brahioradialis 6 Biceps brachii 7 External oblique muscle of abdomen

1 flexor carpi radialis 2 palmaris longus 3 flexor digitorum superficialis 4 flexor carpi ulnaris

 

Surgical approach to axilla

 

Usually the approach to the axilla is performed when the axillary artery is to be exposed. The axillary artery may be ligated at its first or third parts

1st part exposure: Incision is made into skin just below the clavicle and extending from the coracoid process to the sternoclavicular joint. The whole of the clavicular head of the pectoralis major is divided and then the pectoralis minor below it is retracted inferiorly to expose the content of the axilla.

3rd part exposure: Incision into the skin is placed on the surface marking of the brachial artery which is extended upwards to expose the coracobrachialis and the musculocutaneous nerve lying on it. This exposes the branches of the brachial plexus and the 3rd part of axillary artery.

 

 

Clinical aspects of brachial plexus

  • Brachial plexus palsy

    This has the following features-

    • Flaccid paralysis of the entire upper extremity

    • Complete anesthesia of the lower part of the arm, forearm and hand.

    • Subsequent wasting of muscles of the upper extremity

  • Injuries affecting parts of the brachial plexus can be divided into three main types

    • Upper radicular syndrome C5 and 6 (Erb-Duchenne paralysis)

    • Middle radicular syndrome (C7)

    • Lower radicular syndrome (C8 and T1) (Klumpe's paralysis

  1. Erb-Duchenne paralysis  is the commonest type of injury to the brachial plexus and it involves the upper trunk with roots C5 and C6 with damage during complicated child birth. The upper extremity is placed in a the classical waiter's tip position. It is also called upper radicular syndrome.

  2. Middle radicular syndrome affects the middle trunk of the brachial plexus causing paralysis of the radial nerve and its muscles of supply except the nerve to brachioradialis, which is spared. The coracobrachialis is also paralysed in this condition.

  3. Klumpke's paralysis affects the lower trunk of brachial plexus and it is caused by upward traction on the shoulder or during breech delivery. It causes paralysis of the intrinsic muscles of the hand and the flexor muscles of the digits leading  to the characteristic claw hand deformity. There is diminished sensation on the medial side of arm, forearm and hand along the supply of the ulnar nerve.

 

Neurology of the upper extremity

The following major nerves are found in the upper extremity

  • Radial nerve

  • Ulnar nerve

  • Musculocutaneous nerve

  • Median nerve

Radial nerve is injured commmonly in fractures of shaft of humerus, gunshot wounds of axilla and the arm and from axillary crutches and also from axilla being pressured over the edge of a chair as in the so called saturday night paralysis.

Characteristic wrist drop occurs in injuries in the axilla if the lesion occurs in the middle third of the humeus as a result of humeral fracture; it frequently spares the brachioradialis but also causes wrist drop.

Posterior interosseous nerve injury does not cause wrist drop because of the sparing of the extensores carpi radialis longus et brevis. On attempt to perform extension however, the hand maintains radial deviation. Because of the paralysis of the extensor digitorum, the patient is unable to prevent a forced flexion of the fingers.

 

Extensor apparatus

This is called dorsal digital expansion and it covers the dorsum of the proximal phalanx and then wraps around the dorsal and collateral aspects of the metacarpophalangeal joints. The base of the expansion is connected to the extensor digitorum tendon. It then forms a hood called extensor hood which is moveable. This hood is connected to the tendons of lumbricals and the palmar interossei distally and also to the dorsal interossei proximally. Because of the connections to the lumbricals and interossei, the apparatus is capable of extending the interphalangeal joints, while flexing the metacarpophalangeal joints. This is the writing position.

1 collateral slip 2 middle slip 3 lumbrical 4 palmar interossei 5 dorsal interossei 6 extensor digitorum tendon

When the ulnar nerve that supplies the lumbricals and interossei muscles, is damage, then the hand is placed in the position opposite to the writing one. The interphalangeal joints are flexed while the metcarpophalangeal joints are extended. The way to correct this effect is tendon transplant in which the tendons of the flexor digitorum superficialis (supplied wholly by median nerve) are split and connected in each finger to the extensor expansion. This then replaces the action of the lumbricals and interossei and allows the writing position to be maintained once more.

 

 

 

Imaging anatomy
Surgical anatomy
Anesthetic anatomy
Endoscopic anatomy

 

 

 

 

Dissector
Lymphatic drainage
Organ integration
Gross anatomy
Clinical examination

Shoulder joint complex

Glenohumeral joint

Acromioclavicular joint

Elbow joint

Superior radio-ulnar joint

Inferior radio-ulnar joint

Wrist joint

Intercarpal joints

Midcarpal

Carpometacarpal joint of thumb

Carpometacarpal of 2nd to 5th fingers

Intermetacarpal joints

Metacarpophalangeal joints

Interphalangeal joints
Pectoral girdle

 

Injuries to humerus Injuries to radius
Injuries to ulna
Injuries to carpus

See body map

 

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