UL conditions Flashcards
Which structures can supracondylar fractures damage?
Median N and Brachial A, most common in children
Which Nerve can humeral shaft fractures damage?
Radial N as it comes from post humerus round to ant humerus
Damage to Musculocutaneous Nerve?
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. 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.
Sensory functions – loss of sensation over the lateral side of the forearm.
Damage to Axillary Nerve?
The axillary nerve is most commonly damaged by trauma to the shoulder or proximal humerus – such as a fracture of the humerus surgical neck.
Motor functions: Paralysis of the deltoid and teres minor muscles. This renders the patient unable to abduct the affected limb. Sensory functions: The upper lateral cutaneous nerve of arm will be affected, resulting in loss of sensation over the regimental badge area. Patients may report parathesia in this area Characteristic clinical signs: In long standing cases, the paralysed deltoid muscle rapidly atrophies, and the greater tuberosity can be palpated in that area.
Damage to Median Nerve?
Compression of the median nerve within the carpal tunnel can cause carpal tunnel syndrome (CTS). It is the most common mononeuropathy, and is caused by an increased tissue pressure within the carpal tunnel. Clinical features include numbness, tingling, and pain in the distribution of the median nerve. Importantly, the palm is usually spared – as the palmar cutaneous branch does not travel through the carpal tunnel. Symptoms can wake the patient from sleep, and are usually worse in the morning. If left untreated, chronic CTS can cause weakness and atrophy of the thenar muscles.Tests for carpal tunnel syndrome can be performed during physical examination:
Tinel’s sign – tapping the nerve in the carpal tunnel to elicit pain in median nerve distribution.
Phalen’s manoeuvre – holding the wrist in flexion for 60 seconds to elicit numbness/pain in median nerve distribution. Treatment involves the use of a splint, holding the wrist in dorsiflexion overnight to relieve symptoms. If this is unsuccessful, corticosteroid injections into the carpal tunnel can be used. In severe case, surgical decompression of the carpal tunnel may be required
Damage to Ulnar Nerve?
Trauma at the level of the medial epicondyle (e.g. isolated medial epicondyle fracture, supracondylar fracture). It can also be compressed in the cubital tunnel.
All the muscles of innervated by the ulnar nerve are affected.
Flexion of the wrist can still occur, but is accompanied by abduction (due to paralysis of flexor carpi ulnaris and medial half of flexor digitorum profundus).
Abduction and adduction of the fingers cannot occur (due to paralysis of the interossei).
Movement of the 4th and 5th digits is impaired (due to paralysis of the medial two lumbricals and hypothenar muscles).Adduction of the thumb is impaired, and the patient will have a positive Froment’s sign (due to paralysis of adductor pollicis).Characteristic signs: Patient cannot grip paper placed between fingers, positive Froment’s sign, wasting of hypothenar eminence.
Sensory functions: All sensory branches are affected, so there will be a loss of sensation over the areas that the ulnar nerve innervates.
Injury to the brachial plexus can result in what types of palsy?
Upper Brachial Plexus Injury – Erb’s Palsy: Erb’s palsy commonly occurs where there is an excessive increase in the angle between the neck and shoulder, which stretches (or even tears) the nerve roots of C5 and C6. It can occur as a result of result of a difficult birth or shoulder trauma. erves affected: Nerves derived from solely C5 or C6 roots: musculocutaneous, axillary, suprascapular and nerve to subclavius.
Lower Brachial Plexus Injury – Klumpke Palsy. A lower brachial plexus injury results from excessive abduction of the arm (e.g. person catching a branch as they fall from a tree). It has a much lower incidence than Erb’s palsy. Nerves affected: Nerves derived from the T1 root – ulnar and median nerves.
What accounts for the most elbow joint dislocations?
The elbow is one of the most stable joints in the body thanks to the good ‘fit’ (congruity) between the trochlear notch of the ulna and trochlea of the humerus. Sports activities account for up to 50% of elbow dislocations and this type of injury is more commonly seen in adolescent and young adult populations
Posterior dislocation of the elbow- Causes, Associated findings, symptoms / signs , what N is injured?
80-90% of elbow dislocations. through the weak anterior part of the joint capsule
Causes: Fall onto hands with elbows flexed/Hyperextension (blow that drives ulna posteriorly or posterolateral. Associated findings: Ulnar collateral ligament torn. Fractures- head of radius, coronoid process, olecranon process/Ulnar nerve injury. Symptoms / signs of posterior dislocation: Severe pain in the elbow region, Elbow area appears to have become widened, Prominent olecranon process
Ulnar N injured therefore: numbness of medial part of palm and medial one and a half fingers AND weakness of flexion and adduction of the wrist
Bursitis: what are bursa? what is bursitis? symptoms?
Olecranon bursa protects the olecranon process of the ulna. Excessive, repeated pressure and friction over the olecranon can cause inflammation of the bursa. This causes swelling of the bursa which may be visible and is painful on palpation
Sometimes called ‘student’s elbow’
Epicondylitis: what is it? Types?
Inflammation (‘itis’) at the humeral epicondyles. Local tenderness. Pain radiates into forearm on along the affected muscles. Treatment: rest or injection of corticosteroids if pain severe
Medial epicondylitis = inflammation at attachment / origin of the wrist flexor tendons at the medial epicondyle= ‘golfer’s elbow’
Lateral epicondylitis = inflammation at attachment / origin of the wrist extensor tendons at the lateral epicondyle = ‘tennis elbow’
Where do clavicular fractures occur?
The clavicle acts to transmit forces from the upper limb to the axial skeleton. Given its relative size, this leaves it particularly susceptible to fracture. The most common mechanism of injury is a fall onto the shoulder, or onto an outstretched hand.
With the clavicle arbitrarily divided into thirds: 15% of fractures occur in the lateral third, 80% occur in the middle third, 5% occur in the medial third. After a fracture, the lateral end of the clavicle is displaced inferiorly by the weight of the arm, and displaced medially by the pectoralis major. The medial end is pulled superiorly by the sternocleidomastoid muscle.
Management of a clavicular fracture can be conservative (e.g. sling immobilisation) or operative (e.g. open reduction and internal fixation, ORIF). In ORIF, the supraclavicular nerves are often sacrificed – resulting in a post-operative numb patch over the shoulder.
What is the most common shoulder dislocation?
Anterior disclocation (95%) as rotator cuss stabilises superior aspect of shoulder so inferior is weak. Posterior dislocation- Very uncommon humerus every out lightbulb sign.
What can surgical neck fractures result in? signs?
Most common in the elderly can result in Axillary nerve injury: Wasting (atrophy) of deltoid/Reduced or loss of sensation over the C5 dermatome of the skin. Must assess deltoid function and sensation in these injuries. loss of arm abduction 15-90o, flat shoulder deformity due to deltoid atrophy.
What is Winging of the Scapula?
The medial border and inferior angle of scapula pull away from posterior thoracic wall due to Injury to long thoracic nerve – which innervates serratus anterior
Possible Causes:Penetrating injuries when arm abducted e.g. knife wound, Iatrogenic (accidentally caused by doctors) e.g. chest drain, breast surgery, Neuritis (inflammation of the nerve
