Trauma and orthopaedics (5): The elbow Flashcards
osteology of the humerus
do a purpose games
The long bone of the upper arm
- Extends from the shoulder to the elbow
- Proximal aspect articulates with the glenoid fossa of the scapula- glenohumeral joint
- Distally, at the elbow joint, the humerus articulates with the head of the radius and trochlear notch of the ulnar
elbow joint
- Hinge-type synovial joint
2 separate articulations:
- Trochlear notch of the ulna and the trochlea of the humerus
- Head of the radius and the capitulum of the humerus
joint capsule of elbow
Like all synovial joints, the elbow joint has a capsule enclosing the joint
- Strong and fibrous- strengthening the joint
- Thickened medially and laterally to form collateral ligaments- stabilise the flexing and extending motion of the arm
bursae of the elbow
- Membranous sac filled with synovial fluid
- Acts as a cushion to reduce friction between the moving parts of a joint, limiting degenerative damage.
- Key bursae of the elbow
- Intratendinous- located within the tendon of the triceps brachii
- Subtendinous- between the olecranon and the tendon of the triceos brachii, reducing friction between the two structures during extension and flexion of the arm
- Subcutaneous (olecranon) bursa- between the olecranon and the overlying connective tissue
ligaments of the elbow
Joint capsule of the elbow is strengthened by ligaments medially and laterally.
-
Radial collateral ligament (lateral)
- Extends from the lateral epicondyle, blending with the annular ligament of the radius
- Ulnar collateral ligament (medial) originates from the medial epicondyle and attaches to the coronoid process and olecranon of the ulnar
arterial supply of the elbow joint
supply to the elbow joint is from the cubital anastomosis, which includes recurrent and collateral branches from the brachial and deep brachial arteries.
nervous supply of the elbow
Its nerve supply is provided by the median, musculocutaneous and radial nerves anteriorly, and the ulnar nerve posteriorly.
Movement of the elbow
Orientation of the bone forming the elbow joint produces a hinge type synovial joint- allows for extension and flexion of the forearm
- Extension- triceps brachii and anconeus
-
Flexion- brachialis, biceps brachii, brachioradialis
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the upper arm contains 4 muscle
do a purpose games
- 3 in the anterior compartment (biceps brachii, brachialis, coracobrachialis)
- 1 in the posterior compartment (triceps brachii)
All innervated by the musculocutaneous nerve. Good way to remember: BBC- Biceps, Brachialis, coracobrachialis. Arterial supply- muscular branches of the brachial artery.
areas of the elbow
cubital fossa
cubital fossa
An area of transition between the anatomical arm and the forearm- located as a depression the anterior surface of the elbow joint.
borders of the cubital fossa
Triangular shape:
- Lateral border- medial border of the brachioradialis
- Medial border- lateral border of the pronator teres muscle
- Superior border- hypothetical line between the epicondyles of the humerus
- Floor- formed proximally by the brachialis and distally by the supinator muscle
-
Roof- skin and fascia, reinforced by the bicipital aponeurosis
- Within the floor runs the median cubital vein- accessed for venepuncture
Olecranon bursitis
refers to inflammation and swelling of the bursa over the elbow. The olecranon is the bony lump at the elbow, which is part of the ulna bone.
pathophysiology of bursitis
Bursitis is inflammation of a bursa. This causes thickening of the synovial membrane and increased fluid production, causing swelling.
This inflammation can be caused by a number of things:
- Friction from repetitive movements or leaning on the elbow
- Trauma
- Inflammatory conditions (e.g., rheumatoid arthritis or gout)
- Infection – referred to as septic bursitis
olecranon bursitis also known as
“student’s elbow”, as students may lean on their elbow for prolonged periods while studying, resulting in friction and mild trauma leading to bursitis. It can also occur with people with occupations that require leaning on the elbow, such as plumbers or drivers.
presentation of olecranon bursitis
The typical presentation is a young/middle-aged man with an elbow that is:
- Swollen
- Warm
- Tender
- Fluctuant (fluid-filled)
It is important to identify where bursitis is caused by infection. Features of infection are:
- Hot to touch
- More tender
- Erythema spreading to the surrounding skin
- Fever
- Features of sepsis (e.g., tachycardia, hypotension and confusion)
management of bursitis
- Rest
- Ice
- Compression
- Analgesia (e.g., paracetamol or NSAIDs)
- Protecting the elbow from pressure or trauma
- Aspiration of fluid may be used to relieve pressure
- Steroid injections may be used in problematic cases where infection has been excluded
management when infection suspected or cannot be excluded
involves:
- Aspiration of the fluid for microscopy and culture
- Pus indicates infection
- Straw-coloured fluid indicates infection is less likely
- Blood-stained fluid may indicate trauma, infection or inflammatory causes
- Milky fluid indicates gout or pseudogout
- Antibiotics- fluxcloxacillin
patients systemically unwell with infected bursa
Patients that are systemically unwell (e.g., immunocompromised or have sepsis) need admission to hospital for further management, including:
- Bloods (including lactate)
- Blood cultures
- IV antibiotics
- IV fluids
olecranon process fracture RF
occur with a bimodal age distribution; occurring in the young following high energy injuries and in the elderly (more common) following low energy indirect injuries.
olecranon osteology
The olecranon is the region of the proximal ulna from its tip to the coronoid process. It articulates with the trochlea of the distal humerus, and all olecranon fractures are therefore intra-articular fractures by definition
The olecranon is the site of insertion for the triceps muscles.
cause of olecranon fracture
indirect trauma- FOOSH
- causes sudden pull of the triceps muscel
presentation of olecranon fracture
- FOODH
- elbow pain
- swelling
- reduced mobility
- disruption to tricep means there is an inability to extent the elbow against gravity
- shoulder and wrist joint should also be examined
investigations for olecranon fracture
- routine bloods- clotting and group and save
- plain AP and lateral X-ray
- joint and those above and below
- olecranon will usually have a degree of displacement
- CT for complex injury
management of olecranon fractue
- ATLS
- adequate analgesia
- non op management
- op management
non -op management of olecranon fractue
is usually indicated for displacement <2mm, with immobilisation in 60-90 degrees elbow flexion and early introduction of range of motion at 1-2 weeks
- There is increasing use of non-operative management for all patients over 75, irrespective of displacement, as whilst the degree of extension may be lost, the functional outcome is often appropriate
op management of olecranon fracture
is usually indicated for displacement >2mm, requiring (depending on fracture configuration) techniques such as tension band wiring (if fracture proximal to the coranoid process) or olecranon plating (if at level of, or distal to, the coranoid process) may be used
- There is a very high rate of removal of metalwork, as due to the very superficial nature of the injury, it often impacts the patient significantly
radial head fractue is the
most common fracture of the elbow
cause of radial head fracture
indirect trauma
axial loading causes radial head to be pushed against the capitulum of the humerus- FOOSH
This most commonly occurs with the arm in extension and pronation.
presentation of radial head fracture
- FOOSH
- pain and tenderness on palpation over lateral aspect of the low and radial head
- pain on supination and pronation
- swelling and bruising
- shoulder and wrist joints should be examined
investigations for radial head fractue
- routine blood tests, including a clotting screen and a Group and Save.
- AP and lateral X-ray
- joint above and below
- CT may be useful for more complex injiury and comminution
radial head fracture easily missed on Xray
- may only see elbow effusion
- on lateral projection known as ‘sail sign’
- shown as an elevation of anterior fat pad
classification of radial head fracture
- Mason Type 1 – Non-displaced or minimally displaced fracture (<2mm).
- Mason Type 2 – Partial articular fracture with displacement >2mm or angulation.
- Mason Type 3 – Comminuted fracture and displacement (a complete articular fracture).
management of radial head fracture
- ATLS
- analgesia
- check for neurovascular compromise
- definitive management guided by mason classification
management of radial head fracture based on Mason classification
- Mason type 1 injuries – treated non-operatively, with a short period of immobilization with sling (less than 1 week) followed by early mobilisation
- Mason Type 2 injuries – if no mechanical block then can be treated as per a type 1 injury, whilst if a mechanical block is present then these may need surgery (typically an open reduction internal fixation (ORIF))
- Mason Type 3 injuries – will nearly always warrant surgical intervention, either via ORIF or radial head excision or replacement (especially in highly comminuted fractures)
