Radial Head Fractures

Incidence

• Fracture of the radial head can restrict forearm rotation, compromise the stability of the forearm or elbow, and in relatively rare cases, cause radiocapitellar arthrosis.

Classification

Mason

Type	Description
I	Undisplaced fracture
II	Displaced partial articular fracture
III	Comminuted fracture involving the whole head
IV (Johnston)	Radial head fracture with elbow dislocation

Original publication Mason ML. Some observations on fractures of the head of the radius with a review of one hundred cases. Br J Surg. 1954;42(172):123-32.

• Hotchkiss modification grades by displacement, mechanical block and reconstructability

Aetiology

• Fall on outstretched hand with elbow extended and forearm pronated
• Axial load with valgus force
• Component of elbow dislocation and terrible triad injury
• Component of Essex Lopresti injury

Pathology

• Radial head is a secondary valgus stabiliser after the MCL
• Radiocapitellar joint transmits about 60% of axial load across the elbow
• Associated MCL, LCL, coronoid and capitellar cartilage injuries
• Interosseous membrane and DRUJ injury in Essex Lopresti lesions

History

• Low Energy vs High Energy

Examination

• Tenderness over the radial head and elbow effusion
• Assess for a mechanical block to forearm rotation
• Aspirate haemarthrosis and inject local anaesthetic to distinguish pain from block
• Check MCL, interosseous membrane and DRUJ tenderness
• Neurovascular examination including PIN function

Investigations

X-rays

• AP and lateral elbow
• Anterior and posterior fat pad signs indicate an occult fracture
• Radiocapitellar (Greenspan) view profiles the radial head
• Wrist X-rays when the DRUJ or forearm is tender

Treatment

Aims

• The primary goal of treatment is to ensure forearm rotation.
• Incongruity of the radial head in the proximal radioulnar joint causes loss of rotation.

Depends on Injury Pattern

• Isolated Partial Radial-Head Fractures
  • slightly displaced
    • do well with non-operative management
    • does it cause a block to forearm rotation?
      • difficult to assess in acute setting
        • Options
          1. Aspirate haemarthrosis and inject local anaesthetic to examine
          2. Reassess 4-5 days after injury
• Partial Radial-Head Fracture as Part of a Complex Injury
  • Pattern
    1. anterolateral aspect of the radial head is fractured with resultant loss of the anterior buttress of the ulnohumeral joint.
    2. Displaced, partial radial-head fractures are common among patients with posterior olecranon fracture dislocations – older, osteoporotic women
• Fractures Involving the Entire Head of the Radius

Non-operative

• Undisplaced and minimally displaced fractures with no mechanical block
• Sling for comfort with early active motion within days
• Aspiration of haemarthrosis for pain relief
• Follow up X-rays to detect displacement

Operative

• ORIF
  • Indications
    • retaining the fractured radial head amidst complex combined injury with instability of the forearm or elbow,
      1. Essex-Lopresti injury (radial head fracture and rupture of the interosseous ligament of the forearm)
      2. terrible triad injury (posterior dislocation of the elbow with fractures of the radial head and coronoid process)

Complications

• Stiffness
  • Operative fixation can restrict forearm rotation either via
    1. implant prominence,
    2. scarring,
    3. heterotopic bone formation
• Nerve
  • PIN
    • How to avoid
      1. retractors should not be placed around the radial neck,
      2. the forearm should be pronated during exposure of the radial neck
      3. If distal dissection and internal fixation are needed, the nerve should be identified and protected.
• Instability
  • Injury to the lateral collateral-ligament complex, leading to posterolateral, rotatory, elbow instability

Prognosis

• Fracture of the radial head can restrict forearm rotation, compromise the stability of the forearm or elbow, and in relatively rare cases, cause radiocapitellar arthrosis.
• Radial Head Excision:
  • the incidence, severity, and consequences of proximal migration of the radius after excision of isolated radial-head fractures have long been a source of debate

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.