8. Elbow And Forearm Flashcards
3 JOINTS OF FOREARM:
- Elbow
- Proximal radio-ulnar
- Distal radio-ulnar
Bones of forearm
- Distal Humerus
- Radius
- Ulna
Elbow joint
3 articulations
- Humero- radial articualtion = radius and humerus
- Proximal radio – ulnar joint = Radial head and inside ulna
- Humero –ulnar artciulation
Capitulum – smaller lateral surface
• Radial heads fits into this
• Radial fossa above
On distal end of humerus
Trochlear
• Articualr surface around ulna
• Coronaoid fossa above
On distal end of humerus
Fossa
Fossas – small depression allowing bony protrusions to slot into them
Olecranon
Proximal ulna - olecranon process fits into eoecronon fossa
Coronoid process
• Anterior part of ulna
Occupies coronoid fossa
Proximal radius
- Head = cup like shape articulating with capitulum
* Inner side of radial head articulates iwht ulna on radial notch = proximal radio ulna joint
Hummer ulnar articulatiuon
- Trochlear notch ulna
* Trochlea of humerus
Humero radial articualtiuon
- Head radius
* Capitulum humerus
Proximal radio ulnar articualtion
- Head radius
* Radial notch ulna
Flexion of the elbow
- humerus coronoid fossa + ulna coronoid process
* humerus radial fossa + radius head
• humerus olecranon fossa +ulna olecranon
Joint capsule of elbow joint lines the
- radial fossa
- coronoid fossa
- olecranon fossa
- medialsurface trochlea
Joint capsule of elbow joint - structure
• Outer = fibrous
• Inner = synovial
Envelopes top of the radius
Fibrous
• Strongest around the sign
• Weakest in the middle
Fat pads
• Where fossa are that receive radial head and corocid process of ulna
Joint capsule of elbow joint purpose
Purpose = provide protective seal around the joint and structure to joint and synovial fluid
3 ligaments of elbow joint
—> Strengthen the capsule medially and laterally
- Ulnar collateral ligament
- Radial collateral ligament
- Annular ligament = wraps around radial head – jolds radius in psotion but allows movement in supination and pronation
Flexors at elbow joint
• Brachialis
• Biceps brachii
Brachioradialis
Extensors At elbow joint
• Triceps brachii
2 bones of forearm
Radius
ulna
Radius
- Thin at top
- Widens further down
- Only distal end or radius articulates with the wrist
- Styloid process at end or radius – near where you feel pulse
Ulna
- Longer than radius
- Wide at top
- Thin further down
Proximal radio-ulnar joint
- head radius + radial notch ulna
- anular ligament holds it in place
- articular cavity continuous with that of the elbow joint
- Articular disc off the end of radius so ulna articulates with it
Distal radio-ulnarjoint
- head ulna + ulnar notch radius
* articular disc
Supination
• Radius rotates laterally around its longitudinal axis Dorsum of the hand faces posteriorly Palm faces anteriorly
Pronation
• Radius rotates medially around its longitudinal axis Dorsum of the hand faces anteriorly Palm faces posteriorly
2 movements of radial ulnar joint
Supination
Pronation
Supination
2 muscles
- Supinator (when resistance is absent)
* Biceps brachii
Pronation
2 muscles
- Pronator quadratus (primarily) - base of forearm
* Pronator teres (secondarily)
Anterior compartment of forearm
- Contains all of the flexors
- Flex the wrist and digits
- Pronate the hand
posterior compartment of forearm posterior
- Extend the wrist and digits
* Supinate the hand
Anterior compartment contents
• Deep to the skin is
(1) subcutaneoustissue (superficial fascia) containing fat (2) deep fascia compartmentalizing muscles
Deep fascia of the forearm: antebrachial fascia
• extensor retinaculum
• flexor retinaculum
The flexor–pronator muscles are arranged in three layers:
Superficial
Intermediate
Deep
Superificial layer
Lateral (radial head) to medial
- pronator teres
- flexor carpi radialis
- palmaris longus
- flexor carpi ulnaris – supplied by ulna nerve
From lateral to medial – more input for ulna nerve
Other 3 All supply mainly from median nerve
Intermediate layer
• Flexor digitorum superficialis 2 heads • Radial head • Humero ulnar head Supplied by median nerve Controls all of the fingers but not the thumb
Deep layer
Superficial to deep
• Flexor digitorum profundus – dual innervation, laterally controlled by median nerve and medial side is innervated by ulna nerve)
• Flexor pollici longus – controls the thumb
• Pronator quadratis
Cubital fossa boundaries
- Pronator teres – medial
- Brachio radialis – lateral
- Between lateral and medial epicondyle = base
Contents of the cubital fossa
Lateral to medial • Tendon of biceps brachii • Brachial artery • Median nerve Radial nerve is also passing through but hidden under brachoradialis
Ulna nerve – passes behind medial epichondyle
Superior surface of cbital fossa
• Bicepital aponeurosis
Venipuncture in Cubital Fossa
The cubital fossa is the common site for • Blood sampling • Blood transfusion • Intravenousinjections • Introduction of cardiac catheters
because of the prominence and accessibility of veins
Arteries of the forearm
Apex of antecubital fossa
• Brachial artery splits into ulna and radial artery at antecubital fossa
• Ulna artery splits into interosseous artery and deep penetrating arteries
• Ulnar and radial arteries form deep and suoerficial palmar arch
Superifical veins
- Cephaoilic – outside of upper arm
- Basilic vein = inside of upper arm
- Join by medial cubital veins
2 Deep veins of fore curl
- Radial veins
- ulnar veins
- Connect to a deep palmar arch from distal part of hand up into forearm and upper limb
Superficial lymphatic vessels
- From lymphatic plexuses in the skin of the fingers, palm, and dorsum of the hand
- Ascend mostly with the superficial veins, such as the cephalic and basilic veins.
- Some vessels accompanying the basilic vein enter the cubital lymph nodes, located proximal to the medial epicondyle and medial to the basilic vein. Efferent vessels from these lymph nodes terminate in the humeral (lateral) axillary lymph nodes
- Most superficial lymphatic vessels accompanying the cephalic vein enter the apical axillary lymph nodes and deltopectoral lymph nodes.
Deep lymphatic vessels
- Less numerous than superficial vessels
- Accompany the major deep veins in the upper limb (radial, ulnar, and brachial)
- Terminate in the humeral axillary lymph nodes.
- Drain lymph from the joint capsules, periosteum, tendons, nerves, and muscles
Ulnar nerve
Supplies only one and a half muscles:
• the Flexor Carpi Ulnaris (FCU)
• the ulnar part of the Flexor digitorum profundus (FDP)
Median nerve
Principal nerve of the anterior compartment of the forearm
Supplies muscular branches directly to the muscles of the
• superficial and intermediate layers of forearm flexors (except the FCU)
• deep muscles (except for the medial [ulnar] half of the FDP)
via its branch, the anterior interosseous nerve.
Radial nerve
- Deep branch: motor –> Muscles post. compartment forearm
* Superficial branch:sensory —> Skin dorsum of the hand and fingers
3 examples of Traumatic injuries of elbow
- Supracondylar
- Elbow dislocation
- Pulled elbow
4 examples of Inflammatory disease in elbow
- Osteoarthritis
- Rheumatoid arthritis
- Tendinopathy
- Bursitis
Fractures of the elbow:
- Distal humerus
- Supracondylar
- Intercondylar
- Medial or lateral (epi)condyle
- Proximal radius
- Radial head
- Radial neck
- Proximal radius
- Proximal shaft
- Proximal ulna
- Olecranon
- Proximal ulna
- Processus coronoideus
- Proximal ulna shaft
Supracondylar fracture of distal humerus - cause
• Supracondylar = most common due to fall with oustretched hands
Supracondylar humerus fractures
- Most common traumatic injury of the elbow
- Typical age 5-7 years, fall on outstretched arm
• Risk of neurovascular injury(especially type 3)
• Gartland classification –degree of displacement
Type 1: undisplaced = fracture is place
Type 2: posterior cortex intact = one part intact
Type 3: displaced, no contact = 2 bones seperated
Extension fall
• Extension = falling on outstretched hand
Flexion fall
• Flexion = falling on point of elbow
Assessing Supracondylar humerus fractures
Asses for neurovascular injury:
- Median nerve > radial nerve > ulnar nerve (pin fixation) – neuropraxia AIN
- Brachial artery spasm/thrombus/tear: Pulseless warm or cold hand
- Volkmann’s (ischemic) contracture
Vascularity
• Pulse
• Capillary return filling time
• Neurology – ulnar, median (most commonly affected), radial
Pulseless warm hand
- Can’t feel pulse but hand is warm
* Reduce fracture and pulse should return
Cold hand
- Can’t feel pulse after reducing fracture
- Open it
- Hand is cold and white
- Volkmann’s (ischemic) contracture
• Soft tissue injury = increased pressure in forarm = compartment syndrome
Supracondylar humerus fracture Treatment
Type 1 = simple fracture with cast
Type 2 = cast
Type 3 fix gap using wires
Supracondylar humerus fracture Complications
acute
• Depedning on what injury is
long term
• Malunion = growth disturbance: varus or valgus deformity
• If not treated properly deformity round elbow
Pulled elbow (‘nursemaid’s elbow”)
= subluxation of radial head due to longitudinal traction in very young child with ligament laxity. (common 2-4 years)
• Common in very young childtren
• Slipping of radial head
• Annular ligament = attatches radial head to ulna
• Rotation used to put radial head in place
Elbow dislocation
Mechanism of injury:
- axial loading
- supination/externalrotation of the forearm
- valgus posterolateral force
“terrible triad injury”
- Elbow dislocation
- LUCL tear
- Radial head fracture and coronoid tip fracture
Elbow dislocation Treatment
Nonoperative
• closed reduction and splinting at least 90° for 5-10 days, early physiotherapy
indications
• acute simple stable dislocations
• recurrent instability after simple dislocations is rare (<1-2% of dislocations)
Elbow dislocation Treatment
Operative
• ORIF (coronoid, radial head, olecranon), LCL repair, +/- MCL repair
indications
• acute complex elbow dislocations
• persistent instability after reduction = elbow requires >50-60° to maintain reduction
• reduction cannot be performed closed( often due to entrapped soft tissue or osteochondral fragments)
Radial head and neck fractures
- Fall on outstretched hand(ext+pron)
- Pain, swelling and limited ROM
- Mason classification
- Type 1 = in place
- Type 2 = partially displace
- Type 3 = injur
Radial head and neck fractures Associated injuries
—> 35% have associated soft tissue or skeletal injuries including ligamentous injury
• lateral collateral ligament (LCL) injury
• medial collateral ligament (MCL) injury
• combined LCL/MCL
Radial head and neck fractures treatment
Non-operative(undisplaced)
- Short immobilization followed with Physiotherapy
* Good outcome
Radial head and neck fractures treatment
Operative (displaced/associated injuries)
• ORIF – Radial head replacement
2 types of Arthritis of the elbow
- Osteoarthritis
* Rheumatoid arthritis
Oa
- Uncommon primary OA, mostly secondary/ associated with traumatic degeneration or inflammatory disease such as Rheumatoid arthritis
- Clinical findings: crepitations, swelling, pain, locking (loose body)
Rheumatoid arthritis
– 1%of the population – Peak age onset 40-50y – Female > male – Autoimmune disease – Pannus formation (inflamed synovial cell proliferation)
Arthritis of the elbow - Rheumatoid arthritis
- MCP joints of the hands / PIP joints of the fingers Feet – metacarpal joint
- Cervical spine
- Large joint
- Associated organ infiltration: eyes, skin, lungs, heart, kidneys
Arthritis of the elbow - Rheumatoid arthritis
On scans
– Loss of jointspace
– Osteopenia
– Bone erosion
– Subluxation/deformity
Arthritis of the elbow - Rheumatoid arthritis
Treatment
medical/ corticoinjections /joint replacement
Tendinopathy
Inflaamtion of tendons around elbow
Tennis elbow
• “tennis elbow” = lateral epicondylitis
• Extensor tendonipathy ECRB- extensor carpus radialis braevis : stabilizes wrist with elbow extension overuse/inflammation
Self-limiting < 1y Activity modification
Golfers elbow
- = medial epicondylitis
- Flexor tendinopathy
- Repetitive valgus stress : FCR + pronator teres overuse/inflammation
- Self-limiting < 1y Activity modification
Bursitis causes
- Trauma
- Prolonged pressure
- Infection
- Medical conditions
Bursitis treatment
- NSAID
- Aspiration/corticoinjection
- Surgical removal
- Elbow pads
- Surgical drainage /AB (infectious)
Neurologica disorders of the elbow
Cubital tunnel syndrome
= ulnar nerve entrapment
Entrapment between two heads of FCU = tendinous arch enter cubital tunnel
Neurologica disorders of the elbow
Causes
- Prolonged bent position
- Complication of fracture/dislocation (malunion)
- Bone spurs/osteophytes
- Swelling/cyst/tumour
Neurologica disorders of the elbow
Symptoms
- Paraesthesia
- Muscles weakness
Clinical examination/diagnosis:
• Tinel’s test – tapping aorund nerve cause tingling
• Nerve conduction study
Neurologica disorders of the elbow
Treatment
- NSAID
- Bracing in extension at night
- Nerve sliding exercises
- Surgical release/transposition
Cubital tunnel
Epicondyleovecranon ligament / Osborne bone
Lateral - olecranon process of ulna
medial - medial epicondyce of humerus:
Coles fracture
Wrist and hand displaced posteriorly to fracture
Dinner forK deformity
Median nerve palsy
Unable to abduct or oppose thumb
Paralysis of thenar muscles
