Radial Head Fractures: Anatomy, Classification, Clinical Features, Treatment and Complication

Radial head and neck fractures are the most common fractures of the elbow joint

These fractures could be isolated or could be associated with elbow instability, a mechanical block to elbow motion, an injury to distal radioulnar joint and injury to the interosseous membrane

Diagnosed clinically and by plain radiographs and treated non operatively or operatively depending on many factors

Mechanism of injury

Fall on the elbow or a fall on the outstretched hand with the elbow extended and forearm pronated

Anatomy of proximal radius

Radius is the lateral and shorter forearm bone
Proximal end of the radius composed of a short head, neck and medially directed tuberosity
Radial head articulate with the capitulum of the humerus proximally to form radiocapitellar joint and with the radial notch of the ulna medially to form proximal radioulnar joint

DrJanaOfficial, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons

Radial tuberosity is where the biceps tendon insert
The shaft of the radius gradually become bigger and bigger as it passes distally (opposite to ulna)

Classification

Mason classification (modified by Hotchkiss and Broberg-Morrey) on four types:

Type I
Type II
Type III
Type IV

Type I

non displaced or minimally displaced < 2mm, no mechanical block to pronation and supination

Type II

Displaced > 2mm or angulated, possible mechanical block to pronation and supination

Type III

comminuted and displaced fractures, there is mechanical block to pronation and supination

Mason Type III injury; DrJanaOfficial, CC BY-SA 4.0, via Wikimedia Commons

Type IV

any radial head fracture + elbow dislocation

Clinical features

Symptoms

Patient present with elbow pain
they also complain that they can’t rotate their forearm

Physical examination

Look

Elbow swelling
Ecchymosis
Deformity if there is associated elbow dislocation

Feel

there is tenderness on pressure over the radial head
Pain at the distal radioulnar joint is suggestive of an Essex-Lopresti fracture dislocation (explained later) so make sure to palpate the distal radioulnar joint

Move

Assessment of the range of movement at the elbow is important to check for mechanical block and that is done using the local anesthesia test and assessing flexion/extension and pronation/supination

Imaging

AP and lateral elbow X rays: there maybe a clear abnormality or sometimes both views are normal in occult undisplaced fractures
CT or MRI can help better understand the injury and plan the operative management

AP elbow X-ray showing non displaced radial head fracture; by Thomas Zimmermann (THWZ), CC BY-SA 3.0 DE https://creativecommons.org/licenses/by-sa/3.0/de/deed.en, via Wikimedia Commons

Associated injuries

Lateral (80%) and medial collateral ligaments injuries
Other fractures: coronoid, olecranon and carpal fractures
Essex-Lopresti injury (interosseous membrane)
Monteggia fracture dislocation
Terrible triad injury

Essex-Lopresti injury

The combination of a radial head fracture, an injury to the distal radio-ulnar joint and interosseous membrane injury

Can result in progressive forearm displacement and usually requires surgical treatment

Radial head excision can’t be done if this injury is present, because it would result in secondary wrist problems

Monteggia fracture dislocation

The combination of a radial head dislocation (with or without radial head fracture) and proximal ulnar fracture

Radial excision can’t be done if this injury is present, because it would result in elbow instability

Terrible triad injury

Combination of a radial head fracture with ulnar cornoid process fracture and an elbow dislocation

Treatment

Non operative

Indications:

Most of the isolated fractures
Mason type I fractures
Mason type II fractures that are not associated with block to forearm rotation (pronation/ supination)

Fracture immobilized by sling for 1 week, re assessment by X rays to make sure no further displacement occurred

Exercises started as soon as possible and Patients are advised to move the arm freely within the limits of comfort to prevent stiffness

There is loss of the last 5-10 degrees of elbow extension in most cases

Prognosis is good in 90% of patients

Operative

Indications:

Mason type II fractures with mechanical block to forearm rotation
Mason type III fractures
Persistent radiocapitellar crepitus or pain

Operative options:

ORIF
Fragment excision
Prosthetic replacement
Radial head excision: for older patients with low demand

Fractures with two substantial head fragments are best fixated, while more comminuted fractures are treated with either prosthetic replacement of radial head excision

Fragment excision is indicated when there is joint obstruction with a small fragment that is too small to be fixated

In presence of other injuries (Monteggia, Essex-Lopresti) or where there is suspicion of elbow instability then radial head excision is contraindicated and ORIF or prosthetic replacement has to be done

Elbow instability is suspected when there is Loss of the cortical contact of the radial head fragment or a fragment that is greater than a quarter of the radial head surface => should be reduced and fixated

In all operative cases associated with lateral ligament avulsion, this injury should be treated with suture anchor repair back to the humerus

Complications

Elbow stiffness
Loss of elbow range of motion, mostly the last 5-10 degrees of extension occur in most cases
Stiffness is caused by capsular contractures and ossification and the hardware used in fixation
Post traumatic arthritis
This complication occurs due to some incongruity that remained between the joint surfaces
Late complication
Patient complain of pain and restriction of movement
Treated with radial head excision
Malunion and non union
Elbow instability
Surgical site infection
Secondary displacement
Posterior interosseous nerve injury secondary to the operation

Course Menu

This article is apart from The Elbow and Forearm Trauma Free Course; This course contains a number of lectures listed below:

Course Introduction

Distal humerus Fractures

Radial head Fractures

Olecranon Fractures

Elbow Dislocation

Radius and Ulna Shaft Fractures

Monteggia Fracture Dislocation

Galeazzi Fracture Dislocation

Elbow X-ray Interpretation