MSK Clinical Conditions Flashcards
What is thoracic outlet syndrome?
The apex of the axilla region is an opening between the clavicle, first rib and the scapula. In this apex, the vessels and nerves may become compressed between the bones – this is called thoracic outlet syndrome.
What is axillary lymph node enlargement in women an indicator of?
Non-specific indicator of breast cancer
What are some common causes of thoracic outlet syndrome?
Common causes of TOS are trauma (e.g fractured clavicle) and repetitive (seen commonly in occupations that require lifting of the arms)
How does an individual with thoracic outlet syndrome present?
Individual often presents with pain in the affected limb, (where the pain is depends on what nerves are affected), tingling, muscle weakness and discolouration
About how much of the lymph from the breast drains into the axillary lymph node?
Approximately 75% of lymph from the breast drains into the axilla lymph nodes
Why might the lymph in the axillary lymph node be biopsied?
Approximately 75% of lymph from the breast drains into the axilla lymph nodes, so can be biopsied if breast cancer is suspected
If breast cancer is confirmed in a patient who has excessive lymph in their axillary lymph node what is the first step in their treatment?
If breast cancer is confirmed, the axillary nodes may need to be removed to prevent the cancer spreading. This is known as axillary clearance.
During axillary clearance, what nerve may be damaged and what is the result of this?
Long thoracic nerve
Winged scapula
What is the clinical relevance of the cubital fossa and blood pressure?
Brachial artery
The brachial pulse can be felt by palpating immediately medial to the biceps tendon in the cubital fossa. When measuring blood pressure, this is also the location in which the stethoscope must be placed, to hear the korotkoff sounds
What is the clinical relevance of the cubital fossa and venepuncture?
The median cubital vein is located superficially within the roof of the cubital fossa. It connects the basilic and cephalic veins, and can be accessed easily – this makes it a common site for venepuncture
What is a supraepicondylar fracture?
It is a transverse fracture, spanning between the two epicondyles.
When does a supraepicondylar fracture occur?
A supraepicondylar fracture occurs by falling on a flexed elbow
How does a supraepicondylar fracture affect the cubital fossa?
The displaced fracture fragments may impinge and damage the contents of the cubital fossa.
What happens as a result of a supraepicondylar fracture?
Direct damage, or post-fracture swelling can cause interference to the blood supply of the forearm from the brachial artery. The resulting ischaemia can cause Volkmann’s ischaemic contracture –
What artery is damaged in a supraepicondylar fracture?
Brachial artery
What is Volkmann’s ischaemic contracture and what causes it?
Uncontrolled flexion of the hand, as flexors muscles become fibrotic and short
Ischaemia as a result of a supraepicondylar fracture can cause it
What nerves may be damaged in a supraepicondylar fracture?
Median and radial nerve
What is the carpal tunnel syndrome?
Compression of the median nerve within the carpal tunnel can cause carpal tunnel syndrome (CTS). It is the most common mononeuropathy and can be caused by thickened ligaments and tendon sheaths
What is the cause of carpal tunnel syndrome?
Mostly unknown (idiopathic) Trauma Rheumatoid arthritis Acromegaly Myxoedema Pregnancy
Others are diabetes neoplasm amyloidoses
If untreated, what will carpal tunnel syndrome cause?
Weakness and atrophy of the thenar muscles
How will a patient with carpal tunnel syndrome present?
Numbness, tingling and pain in the distribution of the median nerve.
The pain will usually radiate to the forearm.
Symptoms are often associated with waking the patient from their sleep and being worse in the mornings.
What two tests can be performed during physical examination, when suspecting carpal tunnel syndrome?
Tapping the nerve in the carpal tunnel to elicit pain in median nerve distribution (Tinel’s Sign)
Holding the wrist in flexion for 60 seconds to elicit numbness/pain in median nerve distribution (Phalen’s manoeuvre)
What treatment is available for carpal tunnel syndrome?
Treatment involves the use of a splint, holding the wrist in dorsiflexion overnight to relieve symptoms. If this is unsuccessful, corticosterioid injections into the carpal tunnel can be used. In severe case, surgical decompression of the carpal tunnel may be required.
What pulse can be palpated in the anatomical snuff box?
The radial pulse can be palpated in some individuals by placing two fingers on the proximal portion of the anatomical snuffbox.
What carpal bone is most prone to fracture within the anatomical snuff box?
Scaphoid bone
What two bones articulate in the anatomical snuff box to form the wrist joint?
The scaphoid and the radius
What can cause a fracture to the scaphoid bone?
A blow to the wrist (e.g falling on a outstretched hand) where the scaphoid takes most of the force
What is the main indication of a fracture to the scaphoid bone?
Localised pain in the anatomical snuffbox
Why is a scaphoid fracture sometimes considered a clinical emergency?
The scaphoid has a unique blood supply, which runs distal to proximal. A fracture of the scaphoid can disrupt the blood supply to the proximal portion – this is an emergency. Failure to revascularise the scaphoid can lead to avascular necrosis, and future arthritis for the patient.
How common are fractures to the scapula?
Relatively uncommon
Trauma to which region of the body is seen with a fractured scapula?
Chest trauma
In what incidents are fractured scapulae most commonly seen?
High speed road collisions
Crushing injuries
Sports injuries
Why does a fractured scapula not necessarily require an intervention?
The fractured scapula does not require much intervention, as the tone of the surrounding muscles holds the pieces in place for healing to occur.
What may be caused by damage to the long thoracic nerve?
Winged scapula- the scapula protrudes out of the back when pushing with the arm
Paralysis of serratus anterior muscle
What may cause damage to the long thoracic nerve?
Trauma to the shoulder, repetitive movements involving the shoulder or by structures becoming inflamed and pressing on the nerve Surgical procedures (such as axillary clearance) where damage to LTN may occur
What function of the clavicle contributes to it being one of the most fractured bones?
It transmit forces from the upper limb to the axial skeleton
How can a fracture to the clavicle occur?
Fractures commonly result from a fall onto the shoulder, or onto an outstretched hand
What is the most common fracture site on the clavicle?
The most common point of fracture is the junction of the medial 2/3 and lateral 1/3.
After a fracture to the clavicle, how do the muscles solace the clavicle?
After fracture, the lateral end of the clavicle is displaced inferiorly by the weight of the arm, and medially, by the pectoralis major. The medial end is pulled superiorly, by the sternocleidomastoid muscle
What nerves may be damaged when the clavicle is fractured and what muscle does this nerve innervate?
The suprascapular nerves (medial, intermedial and lateral) may be damaged by the upwards movement of the medial part of the fracture.
These nerves innervate the lateral rotators (suprapinatus, infraspinatus and teres minor) of the upper limb at the shoulder
How may an individual with a fracture to their clavicle present and why?
Waiters tip position
Damage to suprascapsular nerve
These nerves innervate the lateral rotators of the upper limb at the shoulder – so damage results in unopposed medial rotation of the upper limb – the ‘waiters tip’ position.
Medial fragment pulled superiorly by sternocleidomastoid muscle
Trapezius can’t pull lateral fragment superiorly due to weight of upper limbs so shoulder drops
Adduction muscles (pec major) pull lateral fragment medially
What is a fracture of the surgical neck?
When a fracture occurs at the surgical neck of the humerus (most common site of fracture in humerus)
When can a surgical neck fracture of the humerus occur?
this occurs by a direct blow to the area, or by falling on an outstretched hand
What nerve is at most risk of damage in a surgical neck fracture of the humerus?
Axillary nerve
What artery is at most risk of damage in a surgical neck fracture of the humerus?
Posterior circumflex humeral artery (branch of axillary artery)
Damage to the axillary nerve in a surgical neck fracture of the humerus will affect which muscles and what movement?
Deltoid
Teres minor
Patient unable to abduct arm
Damage to the axillary nerve in a surgical neck fracture of the humerus will affect which region of skin?
The axillary nerve also innervates the skin over the lower deltoid (known as the regimental badge area), and so sensory innervation here could be lost.
What is a mid shaft fracture of the humerus?
When a fracture occurs in the shaft region of the humerus
Most commonly in region of radial groove
What nerve and artery can be damaged in a mid shaft fracture and why?
Radial nerve
Profunda brachii artery
These are tightly bound to the radial groove
What muscles does the radial nerve innervate in the forearm and how are these affected in a mid shaft fracture?
The radial nerve innervates the extensors of the wrist. In the event of damage to this nerve, the extensors will be paralysed. This results in unopposed flexion of the wrist occurs, known as ‘wrist drop’
How will a patient with damage to their radial nerve present?
Wrist drop- since extensor muscles of forearm are no longer innervated
Sensory loss over dorsal surface of hand and proximal ends of lateral 3 and a half fingers dorsally
What are the two most common distal humeral fractures?
Supraepicondylar fractures
Medial epicondyle fractures
What nerve can become damaged in a medial epicondyle fracture?
Ulnar nerve
When the ulnar nerve is damaged (as in medial epicondyle fracture) how will a patient present?
Claw hand
A deformity known as ulnar claw is the result. There will be a loss of sensation over the medial 1 and 1/2 fingers of the hand, on both the dorsal and palmar surfaces.
What can cause a fracture of the ulna bone?
Fracture occurs as a result of the ulna being hit by an object
What region of the ulna is the most common site for fracture?
The shaft
How will an ulna shaft fracture affect the appearance of the forearm?
Normal muscle tone will pull the proximal ulna posteriorly
When a fracture in the ulnar has occurred why is it necessary to check for a fracture in the radius bone?
Ulna and radius bone are attached by the interosseous membrane.
The force of a trauma to one bone can be transmitted to the other via this membrane.
Thus, fractures of both the forearm bones are not uncommon.
Polo mint analogy
What is a monteggia fracture of the Ulna bone and what causes it?
Monteggia’s Fracture – Usually caused by a force from behind the ulna. The proximal shaft of ulna is fractured, and the head of the radius dislocates anteriorly at the elbow.
What is a Galeazzi’s fracture of the ulna bone?
Galeazzi’s Fracture – A fracture to the distal radius, with the ulna head dislocating at the distal radio-ulnar joint.
What is a Colles fracture of the radius?
The most common type of radial fracture.
Fracture of distal 2cm of radius.
The structures distal to the fracture (wrist and hand) are displaced POSTERIORLY
What can cause a Colles fracture of the radius?
A fall onto an outstretched hand causing a fracture of the distal radius.
How would a patient who has suffered a Colles fracture present?
It produces what is known as the ‘dinner fork deformity’
Describe fractures of the radial head
This is characteristically due to falling on an outstretched hand. The radial head is forced into the capitulum of humerus, causing it to fracture.
What is a smiths fracture of the radius?
A fracture caused by falling onto the back of the hand.
Fracture to distal 2cm of radius
It is the opposite of a Colles’ fracture, as the distal fragment is now placed ANTERIORLY
What two carpal bones are the most commonly fractured?
Lunate and scaphoid
What is the most common cause of a carpal fracture?
Falling on an outstretched hand
What is the main clinical observation of a scaphoid bone fracture?
Pain/ tenderness in anatomical snuffbox
What artery is at risk of damage in a scaphoid bone fracture?
Radial artery
What nerve is at risk of damage in a scaphoid bone fracture?
Radial nerve
In a scaphoid fracture, what can occur as a result of radial artery damage?
Avascular necrosis as blood supply is cut off to a proximal part of bone
When can a lunate fracture occur?
A lunate fracture occurs when falling on a outstretched hand causes hyperextension at the wrist.
What nerve is at risk of damage in a lunate bone fracture?
Median nerve
What is the carpal tunnel syndrome?
The carpal tunnel contains many tendons and the median nerve
Compression of the median nerve within the carpal tunnel can cause carpal tunnel syndrome (CTS).
It is the most common mononeuropathy.
What is the cause of carpal tunnel syndrome?
Its exact cause is not known, but it is thought to be due to thickening of the ligaments and synovial tendon sheaths of the tendons, brought on by overuse or increased pressure on this wrist.
What are the typical symptoms of carpal tunnel syndrome?
Pins and needles in the sensory distribution of the median nerve
Weakness of thenar muscles
The patients history will comment on numbness, tingling and pain in the distribution of the median nerve. The pain will usually radiate to the forearm. Symptoms are often associated with waking the patient from their sleep and being worse in the mornings.
How can a patient with Carpal tunnel syndrome be treated?
Treatment involves the use of a splint, holding the wrist in dorsiflexion overnight to relieve symptoms.
If this is unsuccessful, corticosterioid injections into the carpal tunnel can be used.
In severe case, surgical decompression of the carpal tunnel may be required- cutting into the flexor retinaculum, relieving the pressure
What are the two most common fractures of the metacarpal bones?
Boxers fracture
Bennetts fracture
What is Bennett’s fracture of the metacarpal bones and what is it caused by?
Caused by hyperabduction of the thumb, fracture normally occurs close to the carpometacarpal joint
What is the Boxers fracture of the metacarpal bones and what is it caused by?
Usually caused by a clenched fist striking a hard object.
It is a fracture of the neck of the 5th and occasionally the 4th metacarpal bones. The fingers look shorter as the distal fragments are pushed proximally.
What’s the best way to test the accessory nerve?
By testing how well the trapezius is functioning- Can be achieved by getting the patient to elevate their shoulder against resistance
What muscle does the accessory nerve supply?
The trapezius muscle
In what position does the tendon of the supraspinatus muscle and the coraco-acromial arch rub together? And what bursa normally reduces this friction?
When the arm is abducted, the tendon of the supraspinatus muscle ‘rubs’ against the coraco-acromial arch.
The friction is reduced by the subacromial bursa.
What can cause the painful arc syndrome?
Under repetitive use and abduction, there are degenerative changes in both the subacromial bursa and the supraspinatus tendon.
What is the characteristic sign of painful arc syndrome?
The chracteristic sign is the ‘painful arc’ – pain in the middle of abduction, where the affected area comes into contact with the acromion
What can cause the humerus to irritate the coraco-acromial arch and in turn what else can this cause?
Repetitive use of the rotator cuff muscles can cause the head of the humerus and the muscles to irritate the coraco-acromial arch, which in turn causes inflammation of the rotator cuff. Over a long period of time this can develop into rotator cuff tendonitis.
How common is the rupturing of a tendon in the body?
A complete rupture of any tendon in the body is rare.
How common is the rupture of the biceps brachii tendon?
the long head of the biceps brachii is one of the more common tendons to rupture
What sign would a patient who has a ruptured biceps brachii tendon present with and what other symptoms?
This produces a characteristic sign on flexing the elbow – a bulge where the muscle belly is, called the ‘Popeye Sign’. The patient would not notice much weakness in the upper limb due to the action of the brachialis and supinator muscles.
What is lateral epicondylitis?
Lateral epicondylitis (or tennis elbow) refers to inflammation of the periosteum of the lateral epicondyle.
What is the peak age of onset of lateral epicondylitis?
40-50 years old
What is lateral epicondylitis also known as?
Tennis elbow
What is the cause of lateral epicondylitis?
It is caused by repeated use of the superficial extensor muscles, which strains their common tendinous attachment to the lateral epicondyle.
Tennis players
What is wrist drop a clinical sign of?
Radial nerve injury
In which two regions does radial nerve damage most commonly occur?
Axilla – injured via humeral dislocations or fractures of the proximal humerus.
Radial groove of the humurus - injured via a humeral shaft fracture.
What happens to all of the muscles of the posterior extensor compartment of the forearm when the radial nerve is damaged and how does this cause wrist drop?
These muscles are paralysed
Flexor muscles of anterior forearm are unaffected since they are supplied by the median and ulnar nerve
Therefore the tone of the flexor muscles produces unopposed flexion at the wrist joint and consequently wrist drop
What is the most common cause of axillary nerve injury?
Anterior dislocation of the humerus at the glenohumeral joint, or a fracture of the humerus at the surgical neck.
Injury to the Axillary nerve affects which muscles and movement?
Paralysis of the deltoid and teres minor muscles. This renders the patient unable to abduct the affected limb.
Which branch of the axillary nerve will be non-functional and thus which area of skin will lose sensation in axillary nerve injury?
A branch of the axillary nerve, the lateral cutaneous nerve of arm will be non functional, resulting in loss of sensation over the regimental badge area.
What is a characteristic clinical side of axillary nerve damage?
In long standing cases, the paralysed deltoid muscle rapidly atrophies, and the greater tuberosity can be palpated in that area.
What is the most common cause of musculocutaneous nerve damage?
An injury to the musculocutaneous nerve is relatively uncommon, as it is well protected within the axilla. The most common cause is a stab wound to the axilla region.
Injury to the musculocutaneous nerve affects which muscles and movements?
The coracobrachialis, biceps brachii and brachialis muscles are paralysed. Flexion at the shoulder is weakened, but can still occur due to the pectoralis major. Flexion at the elbow is also affected, but can still be performed because of the brachioradialis muscle. Also, supination of the affected limb is greatly weakened, but is produced by the supinator muscle.
Which area of skin loses innervation when the musculocutaneous nerve is damaged?
Loss of sensation over the lateral side of the the forearm.
If untreated what can carpal tunnel syndrome cause?
If left untreated, CTS can cause weakness and atrophy of the thenar muscles.
What two tests for carpal tunnel syndrome can be performed in physical examination?
Tests for CTS can be performed during physical examination:
Tapping the nerve in the carpal tunnel to elicit pain in median nerve distribution (Tinel’s Sign)
Holding the wrist in flexion for 60 seconds to elicit numbness/pain in median nerve distribution (Phalen’s manoeuvre)
In what to places can the median nerve be damaged?
At the elbow
At the wrist
How can median nerve damage at the elbow occur?
Supracondylar fracture of the humerus
Injury to the median nerve at the elbow joint can affect which muscles and movements?
The flexors and pronators in the forearm are paralysed, with the exception of the flexor carpi ulnaris and medial half of flexor digitorum profundus. The forearm constantly supinated, and flexion is weak (often accompanied by adduction, because of the pull of the flexor carpi ulnaris).
Flexion at the thumb is also prevented, as both the longus and brevis muscles are paralysed.
The lateral two lumbrical muscles are paralysed, and the patient will not be able to flex at the MCP joints or extend at IP joints of the index and middle fingers.
Which area of skin loses innervation when the median nerve is damaged at the elbow joint and wrist?
Lack of sensation over the areas that the median nerve innervates.
What is a characteristic sign of median nerve damage at the elbow joint and wrist?
The thenar eminence is wasted, due to atrophy of the thenar muscles. If patient tries to make a fist, only the little and ring fingers can flex completely. This results in a characteristic shape of the hand, known as hand of benediction
How can median nerve damage occur at the wrist joint?
Lacerations just proximal to the flexor reticaculum
In median nerve injury at the wrist joint which muscles and movements are affected?
Thenar muscles paralysed, as are the lateral two lumbricals. This affects opposition of the thumb and flexion of the index and middle fingers.
In what four regions can radial nerve damage occur?
In the Axilla
In the Radial Groove
Deep Branch of Radial Nerve
Superficial Branch of the Radial Nerve
How can damage to the radial nerve occur in the axilla region?
Dislocation of humerus at the glenohumeral joint or fractures of proximal humerus. Can also happen via excessive pressure on the axilla, e.g. a badly fitting crutch.
In radial nerve injury in the axilla region which muscles and movements are affected?
Triceps brachii and muscles in posterior compartment are paralysed. The patient is unable to extend the forearm, wrist and fingers. Unopposed flexion of wrist occurs, known as wrist drop.
Which area of skin loses sensation when the radial nerve is damaged in the axilla region?
All four cutaneous branches of the radial nerve are affected. There will be a loss of sensation over the lateral and posterior upper arm, posterior forearm, and dorsal surface of the lateral three and a half digits.
How can damage to the radial nerve occur in the radial groove?
Fracture of the shaft of the humerus – damaging the radial nerve when it is bound in the radial groove.
In radial nerve injury in the radial groove which muscles and movements can be affected?
The triceps brachii may be weakened, but is not paralysed. The deep branch of the radial nerve is affected, so the muscles in the posterior compartment of the forearm are paralysed. The patient is unable to extend the wrist and fingers. Unopposed flexion of wrist occurs, known as wrist drop.
Which area skin loses sensation when the radial nerve is damaged in the radial groove?
The cutaneous branches to the arm and forearm have already arisen. The superficial branch of the radial nerve will be damaged, resulting in sensory loss on the dorsal surface of the lateral three and half digits, and their associated palm area.
How can damage to the deep branch of the radial nerve occur?
Fractures of the radial head, or a posterior dislocation of the radius at the elbow joint.
In injury to the deep branch of the radial nerve which muscles and movements are affected?
Muscles in posterior compartment of the forearm are affected – except for the supinator and extensor carpi radialis longus. The extensor carpi radialis longus is a strong extensor at the wrist, and so wristdrop does not occur.
Which area of skin loses sensation when damage to the deep branch of the radial nerve occurs?
None, as it is a motor nerve.
How can damage to the superficial branch of the radial nerve occur?
Stabbing or laceration of the forearm.
In damage to the superficial branch of the radial nerve, which muscles and movements are affected?
None, as it is a sensory nerve.
Which area of skin loses sensation when the superficial branch of the radial nerve is damaged?
Loss of sensation over the lateral and posterior upper arm, posterior forearm, and dorsal surface of the lateral three and a half digits.
In what two regions can ulnar nerve damage occur?
At elbow
At wrist
How can damage to the ulnar nerve at the elbow occur?
The nerve is most vulnerable to injury at the medial epicondyle, so fracture of the medial epicondyle is the most common way of damaging the ulnar nerve
In damage to the ulnar nerve at the elbow which muscles and movement for affected?
Flexor carpi ulnaris and medial half of flexor digitorum profundus paralysed. Flexion of the wrist can still occur, but is accompanied by abduction. The interossei are paralysed, so abduction and adduction of the fingers cannot occur. Movement of the little and ring fingers is greatly reduced, due to paralysis of the medial two lumbricals.
Which area of skin loses sensation when the ulnar nerve is damaged at the elbow?
All sensory branches are affected, so there will be a loss of sensation over the areas that the ulnar nerve innervates.
What is a characteristic sign of ulnar nerve injury at the elbow?
Patient cannot grip paper placed between fingers.
How can damage to the ulnar nerve occur at the wrist?
Lacerations to the wrist
In ulnar nerve injury at the wrist which muscles and movements are affected?
The interossei are paralysed, so abduction and adduction of the fingers cannot occur. Movement of the little and ring fingers is greatly reduced, due to paralysis of the medial two lumbricals. The two muscles in the forearm are unaffected
Which area of skin loses sensation when ulnar nerve injury to the wrist occurs?
The palmar branch and superficial branch are usually severed, but the dorsal branch is unaffected. Sensory loss over palmar side of medial one and a half fingers only.
What is a clinical sign of ulnar nerve injury in the wrist?
Patient cannot grip paper placed between fingers. For long-term cases, a hand deformity called ‘Ulnar Claw’ develops
What does the ulnar claw look like?
Hyper-extension of the metacarpophalangeal joints of the little and ring fingers – this is because of the paralysis of the medial two lumbricals, and the now unopposed action of the extensor muscles
Flexion at the interphalangeal joints of the little and ring fingers- because of the unopposed action of FDP (only visible when injury is at wrist and FDP is still functional)
If the lesion has occurred close to the elbow, this might not be evident as the flexor digitorum profundus will be paralysed and so little and ring fingers cannot flex