COurtesy: Ashok Shyam, IORG, OrthoTV

Supracondylar Fracture of the Humerus: Complete Revision

Classification

Based on displacement

• Extension type (approximately 95%).
• Posteromedial displacement is commonly associated with radial nerve injury.
• Posterolateral displacement is commonly associated with median nerve or anterior interosseous nerve injury.
• Flexion type fractures are uncommon.
• Flexion type injuries have a higher risk of ulnar nerve injury.

Gartland classification

• Type I: Undisplaced fracture.
• Type IIA: Angulation without rotation.
• Type IIB: Angulation with rotational deformity.
• Type III: Completely displaced fracture.
• Type IV: Multidirectional instability due to complete periosteal disruption.

Bahk classification

• Typical transverse fracture.
• Medial oblique fracture.
• Lateral oblique fracture.
• High transverse fracture.
• Sagittal oblique fracture.
• Atypical fracture patterns are more unstable and often require modification of pin configuration.

Clinical Evaluation

Neurovascular examination

• Rock sign assesses the radial nerve.
• Paper test assesses the ulnar nerve.
• Scissors or OK sign assesses the median nerve and anterior interosseous nerve.

Clinical warning signs

• Puckering sign suggests brachialis muscle interposition and predicts a difficult reduction.
• Early compartment syndrome is suggested by the three A’s:
  • Anxiety.
  • Agitation.
  • Increasing analgesic requirement.

Radiographic Evaluation

Anterior humeral line

• Should pass through the capitellum on the lateral radiograph.

Baumann angle

• Normal value is approximately 70 to 75 degrees.

Rotational deformity

• Unequal fragment width on the anteroposterior radiograph suggests a Gartland Type IIB fracture.

Management

Type I fractures

• Immobilization in a cast.
• Medial column comminution is an indication for percutaneous pin fixation.

Type IIA fractures

• Cast treatment if the anterior humeral line intersects the capitellum.
• Closed reduction and percutaneous pinning if reduction is unsatisfactory.

Type IIB fractures

• Closed reduction and percutaneous pinning.

Type III and Type IV fractures

• Closed reduction and percutaneous pinning is the treatment of choice.

Closed Reduction Technique

• Apply longitudinal traction.
• Correct coronal plane displacement.
• Flex the elbow while applying pressure over the olecranon.
• Maintain reduction with forearm positioning.
• Pronation stabilizes posteromedial displacement.
• Supination stabilizes posterolateral displacement.

Pinning Principles

Preferred construct

• Two or three divergent lateral pins.
• Cross pinning for unstable fractures.

Principles of K wire fixation

• Obtain bicortical purchase.
• Engage both proximal and distal fragments.
• Diverge the pins across the fracture site.
• Avoid intramedullary pin placement.

Indications for medial pinning

• Medial column comminution.
• Oblique fracture patterns.
• Persistent instability.

Difficult Fracture Patterns

High supracondylar fractures

• Lateral pins may become intramedullary.
• Increased risk of varus collapse.
• Consider transolecranon pinning or crossed pin fixation.

Type IV fractures

• Joystick reduction technique is often useful.

Flexion type fractures

• Reduce with the elbow in extension.
• Transolecranon pinning may occasionally be required.

Irreducible fractures

Causes

• Brachialis muscle interposition.
• Neurovascular bundle entrapment.

Management

• Mini open anterior approach.

Nerve Injuries

Common nerve injuries

• Median nerve and anterior interosseous nerve are the most commonly injured.
• Radial nerve is the second most common.
• Ulnar nerve injuries occur in flexion type fractures and may be iatrogenic during medial pinning.

Recovery

• Approximately 90 percent recover spontaneously.
• Recovery usually occurs within 2 to 6 months.

Indications for nerve exploration

• No recovery after 3 to 6 months.
• Persistent radial nerve palsy.
• Multiple nerve injuries.

Iatrogenic ulnar nerve palsy

• Observation is usually appropriate.
• Routine removal of the medial pin is not recommended.

Vascular Injury

Pulseless pale hand

• Surgical emergency.
• Immediate fracture reduction.
• Immediate vascular exploration if perfusion does not improve.

Pulseless pink hand

• Perform fracture reduction first.
• Reassess vascular status after fixation.

Observation is appropriate when

• Hand remains well perfused.
• No associated neurological deficit.

Vascular exploration is indicated when

• Poor perfusion persists.
• Median nerve injury is present.
• Circulation deteriorates during observation.

Late Presentation

Less than 10 days

• Attempt closed reduction and percutaneous pinning.

Between 10 and 20 days

• Accept the best possible reduction.

More than 20 days

• Avoid forceful reduction.
• Correct residual deformity later with osteotomy if required.

Reduction aids

• Intrafocal K wire.
• Joystick technique.
• Artery forceps reduction.

Avoid

• Aggressive open reduction because of the risk of stiffness and myositis ossificans.

Acceptable Reduction

Deformities that must be corrected

• Coronal plane deformity.
• Rotational deformity.

Acceptable residual deformity

• Mild sagittal plane angulation.
• Translation of approximately 20 to 30 percent.

Complications

• Cubitus varus deformity.
• Nerve injury.
• Compartment syndrome.
• Elbow stiffness.
• Myositis ossificans.
• Volkmann ischemic contracture.

Exam Pearls

• Medial column comminution increases the risk of cubitus varus.
• The intact periosteal hinge guides fracture reduction.
• Properly inserted lateral pins provide stability comparable to crossed pins in many fractures.
• Adhere strictly to the principles of K wire fixation.
• Always assess the Baumann angle after fixation.
• Confirm that the anterior humeral line intersects the capitellum.

SUPER Approach

• S – Study the fracture.
• U – Understand the fracture personality.
• P – Plan the reduction.
• E – Execute stable fixation.
• R – Review the final outcome.