Orthopaedic Surgery - Supracondylar Elbow Fracture

Basics

A supracondylar humerus fracture occurs through the:

Distal humeral metaphysis

just proximal to the:

Elbow joint.

The fracture commonly passes through the relatively thin region of bone surrounding the:

Olecranon fossa.

Age-Related Injury Pattern

The same hyperextension mechanism produces different injury patterns according to age.

In:

Children

it commonly produces a:

Supracondylar humerus fracture.

In:

Toddlers

injury may instead involve the:

Distal humeral physis.

In:

Adults

a comparable mechanism more commonly results in:

Elbow dislocation

or other distal humeral fracture patterns.

Classification by Mechanism

Supracondylar fractures are classified as:

Extension type

or

Flexion type.

Extension-Type Fracture

Approximately:

95%

are extension-type injuries.

They typically occur after a:

Fall on an outstretched hand

with the elbow forced into:

Hyperextension.

Flexion-Type Fracture

Flexion-type fractures are:

Uncommon.

They usually result from a direct fall onto a:

Flexed elbow.

Gartland Classification

The:

Gartland classification

is the most commonly used system for extension-type supracondylar fractures.

Gartland Type I

Type I fractures are:

Nondisplaced.

Overall alignment is maintained, although an occult fracture may be suggested by:

Elbow effusion or posterior fat-pad sign.

Gartland Type II

Type II fractures are:

Displaced but retain some cortical continuity.

A posterior cortical hinge is typically preserved.

Gartland Type III

Type III fractures are:

Completely displaced

with no meaningful cortical contact between the:

Proximal and distal fragments.

These injuries have a substantially greater risk of:

Neurovascular complications.

Gartland Type IV

Type IV fractures are unstable in both:

Flexion

and

Extension.

This multidirectional instability usually reflects:

Complete periosteal disruption.

Synonym

A broader term is:

Distal humerus fracture

although this includes several other fracture patterns besides supracondylar injuries.

Epidemiology

Supracondylar humerus fracture is one of the most common:

Elbow fractures in children.

Age

The mean age at injury is approximately:

6 years.

Most occur in children between approximately:

5 and 7 years of age.

Sex

The injury occurs in both sexes with an approximately:

Equal distribution.

Adults

True supracondylar fractures are:

Uncommon in adults.

Adult distal humeral fractures overall have historically occurred at rates around:

5–6 per 100,000 persons per year.

Risk Factors

The principal risk factor is:

Fall on an outstretched upper extremity.

Participation in activities associated with falls, such as:

Playground activity

Sports

and

Cycling

may increase exposure to the typical mechanism.

Etiology

The classic mechanism is:

Fall on an outstretched hand

with the elbow driven into:

Hyperextension.

Extension Mechanism

During hyperextension, the:

Olecranon

acts as a fulcrum against the:

Olecranon fossa.

This concentrates force through the thin distal humeral metaphysis and produces:

Fracture.

Flexion Mechanism

Rarely, a direct fall onto a:

Flexed elbow

drives the distal fragment:

Anteriorly

and produces a:

Flexion-type supracondylar fracture.

Associated Conditions and Injuries

Important associated injuries include:

Ipsilateral forearm fracture

Brachial artery injury

and injuries to the:

Median

Anterior interosseous

Radial

or

Ulnar nerves.

Floating Elbow

A supracondylar fracture associated with an ipsilateral:

Forearm fracture

is sometimes called a:

Floating elbow.

This combination requires particularly careful monitoring for:

Compartment syndrome.

Diagnosis

Diagnosis is based on:

Trauma history

Physical examination

and

Radiographs.

Signs and Symptoms

Patients usually present after an acute injury with:

Severe elbow pain

Swelling

and refusal or inability to:

Move the arm.

Deformity

Displaced fractures may produce obvious:

Elbow deformity.

Ecchymosis

Bruising may develop in the:

Antecubital fossa

within several hours after injury.

Nerve Injury

Neurologic injury may present as inability to perform normal:

Finger

Thumb

or

Wrist movements.

Arterial Injury

Brachial artery compromise may produce:

Absent pulse

Pallor

Coolness

Delayed capillary refill

and, in severe ischemia,

Loss of motor function.

Physical Examination

The examination should be systematic and include:

Inspection

Palpation

Motor testing

Sensory testing

and careful:

Vascular assessment.

Swelling

Substantial swelling around the:

Elbow

is common.

Rapidly increasing swelling requires concern for:

Vascular injury or compartment syndrome.

Type III Deformity

A completely displaced fracture may create an:

S-shaped appearance

around the elbow and can sometimes resemble:

Elbow dislocation.

Skin Assessment

Inspect for:

Skin puckering

Tenting

Open injury

or threatened:

Skin viability.

Neurovascular Examination

A thorough neurovascular examination should be performed:

Before and after any reduction.

Documentation is essential because nerve and vascular injury are relatively:

Common.

Motor Examination

Motor testing should include the:

Median nerve

Anterior interosseous nerve

Radial nerve

and

Ulnar nerve.

Anterior Interosseous Nerve

The anterior interosseous nerve can be tested by asking the patient to make an:

“OK” sign

using the:

Thumb and index finger.

Weakness may produce a flattened:

Pinch posture.

Median Nerve

Median nerve motor function can be assessed by:

Thumb opposition

or finger flexion, depending on the child’s cooperation.

Radial Nerve

Ask the patient to:

Extend the wrist or fingers.

Ulnar Nerve

Ask the patient to:

Abduct or adduct the fingers

when cooperation permits.

Sensory Examination

Sensation should be tested in the:

Median

Radial

and

Ulnar nerve distributions.

Vascular Examination

Assess:

Radial pulse

Skin color

Temperature

and

Capillary refill.

Pulseless Hand

A child may have a:

Pulseless but well-perfused hand

after supracondylar fracture.

This situation requires urgent orthopaedic evaluation and careful reassessment after:

Reduction.

Poorly Perfused Hand

A pulseless hand that is:

Pale

Cool

or has poor capillary refill represents a:

Vascular emergency.

Compartment Syndrome

Severe pain with passive stretch of the:

Fingers

may indicate evolving:

Forearm compartment syndrome.

Other concerning findings include:

Increasing analgesic requirement

Tense swelling

and worsening:

Neurovascular status.

Imaging

Plain Radiographs

Standard:

AP

and

Lateral radiographs

of the distal humerus and elbow are usually sufficient.

Imaging Technique

Because the injured child may be unable to fully extend the elbow, imaging should be centered carefully on the:

Distal humerus.

Posterior Fat-Pad Sign

In an occult nondisplaced fracture, the only radiographic clue may be a:

Posterior fat-pad sign.

Visualization of a posterior fat pad after trauma strongly suggests:

Intra-articular fracture.

Anterior Humeral Line

On the lateral radiograph, the:

Anterior humeral line

should normally pass through the middle portion of the:

Capitellum.

Posterior displacement of the distal fragment may cause the line to pass anterior to the:

Capitellum.

Baumann Angle

The:

Baumann angle

on the AP radiograph can help assess:

Coronal alignment

and risk of:

Varus malunion.

Differential Diagnosis

Important alternative diagnoses include:

Elbow dislocation

Lateral condyle fracture

Medial condyle fracture

Intercondylar or bicondylar distal humerus fracture

and, in toddlers,

Distal humeral physeal injury.

Treatment

Treatment depends on:

Fracture displacement

Stability

Neurovascular status

and

Soft-tissue condition.

Initial Stabilization

Until definitive orthopaedic assessment, the elbow should be immobilized in a:

Well-padded splint

with the elbow in modest flexion.

Flexion During Initial Splinting

Approximately:

20–30° of elbow flexion

may be used when swelling or vascular status is concerning.

The goal is to avoid additional:

Displacement

and

Neurovascular compromise.

Excessive Flexion

Elbow flexion beyond approximately:

90°

can increase:

Forearm compartment pressure

and potentially compromise:

Brachial artery flow.

Therefore, excessive flexion should be avoided, particularly in:

Swollen displaced fractures.

Gartland Type I Treatment

Type I injuries are generally treated with:

Immobilization.

A long-arm splint or cast is typically used for approximately:

3 weeks

depending on healing and symptoms.

Gartland Type II Treatment

Type II injuries may be treated with:

Closed reduction

followed by:

Casting

or

Percutaneous pin fixation

depending on:

Alignment

Rotational stability

Swelling

and reliability of:

Cast position.

Gartland Type III Treatment

Type III injuries generally require:

Closed reduction and percutaneous pinning.

Gartland Type IV Treatment

Type IV fractures are multidirectionally unstable and typically require:

Operative reduction and pin fixation.

Analgesia

Pain control may include:

Acetaminophen

and, when necessary,

Short-term opioid analgesia.

Physical Therapy

Formal physical therapy is generally:

Not routinely required in children.

Most children recover elbow motion spontaneously after:

Fracture healing and cast removal.

Adult Rehabilitation

In adults, structured physical therapy is more commonly used because elbow stiffness is:

More problematic.

Surgery

Closed reduction should be attempted under appropriate:

Sedation or anesthesia

for displaced unstable fractures.

Reduction Goals

The goals are to restore:

Sagittal alignment

Coronal alignment

Rotation

and normal relationship of the:

Distal humeral fragments.

Open Reduction

Open reduction may be required when:

Closed reduction fails

or when there is concern for:

Entrapped soft tissue

Open fracture

Persistent vascular compromise

or another mechanical block.

Timing of Surgery

In a child with a well-perfused limb and no urgent complication, fixation can often be performed:

Urgently but not necessarily immediately overnight.

A delay of less than approximately:

24 hours

has not consistently been associated with worse outcomes when:

Neurovascular status is stable.

Percutaneous Pinning

Unstable fractures are commonly stabilized with:

Kirschner wires.

Lateral Pinning

Two or three:

Lateral-entry pins

can provide stable fixation while avoiding direct risk to the:

Ulnar nerve.

Crossed Pinning

Crossed medial and lateral pins may provide excellent:

Mechanical stability

but placement of a medial pin increases the risk of:

Iatrogenic ulnar nerve injury.

Pin Selection

The configuration is chosen according to:

Fracture pattern

Stability after reduction

and surgeon:

Preference.

Flexion-Type Fractures

Flexion-type supracondylar fractures are generally treated with:

Reduction and pin fixation

when significantly displaced.

Postoperative Immobilization

After fixation, the elbow is usually immobilized for approximately:

3–4 weeks.

Pin Removal

Percutaneous pins are commonly removed around:

3–4 weeks

once adequate healing is present, although timing may vary according to:

Fracture pattern

and

Radiographic healing.

Vascular Injury

After reduction and fixation, perfusion should be reassessed by examining:

Pulse

Capillary refill

Color

and

Temperature.

Persistent Poor Perfusion

If the hand remains:

Pulseless and poorly perfused

after reduction, urgent:

Vascular exploration

may be necessary.

Compartment Syndrome

Prompt recognition of vascular compromise and excessive swelling helps reduce the risk of:

Compartment syndrome.

If established compartment syndrome develops, urgent:

Fasciotomy

is required.

Follow-Up

Children require clinical and radiographic follow-up to verify:

Maintenance of reduction

and

Fracture healing.

Early Monitoring

Early follow-up should reassess:

Neurovascular status

Cast or splint condition

and

Alignment.

After Healing

Following fracture union, the patient should be assessed for:

Elbow motion

Carrying angle

and residual:

Deformity.

Prognosis

The prognosis is generally:

Excellent

when alignment and neurovascular status are restored promptly.

Motion Recovery

Most children gradually regain near-normal:

Elbow range of motion

without formal therapy.

Malunion

Poor alignment during healing may cause:

Angular deformity.

The most characteristic is:

Cubitus varus.

Complications

Nerve Injury

Transient nerve injuries are relatively common.

The:

Anterior interosseous branch of the median nerve

is frequently affected in extension-type injuries.

The:

Radial nerve

and

Ulnar nerve

may also be injured depending on:

Fracture displacement and type.

Nerve Recovery

Most traumatic neurapraxias recover spontaneously over:

Weeks to months.

Persistent deficits require further:

Evaluation.

Brachial Artery Injury

The:

Brachial artery

may be stretched, kinked, trapped, or injured by displaced fracture fragments.

Compartment Syndrome

Compromised arterial flow or severe swelling may lead to:

Forearm compartment syndrome.

Volkmann Ischemic Contracture

Untreated compartment syndrome can result in:

Volkmann ischemic contracture

with permanent:

Muscle fibrosis

Joint contracture

and

Neurologic dysfunction.

Cubitus Varus

Malunion can produce:

Cubitus varus

or a:

Gunstock deformity.

This is primarily caused by:

Coronal and rotational malalignment

rather than growth disturbance.

Elbow Stiffness

Temporary stiffness is common after immobilization, but persistent stiffness is relatively:

Uncommon in children

when the fracture heals in good alignment.

Trochlear Osteonecrosis

Rarely, vascular disturbance of the trochlea may produce:

Osteonecrosis

and a late:

Fishtail deformity.

Iatrogenic Ulnar Nerve Injury

Medial pin placement can injure the:

Ulnar nerve.

This risk is reduced when fixation can be achieved using:

Lateral-entry pins alone.

Patient Monitoring

Patients should be monitored for:

Pain

Swelling

Neurovascular status

Alignment

Fracture healing

and recovery of:

Elbow motion.

Key Principle

Supracondylar humerus fracture is a common pediatric elbow injury occurring through the distal humeral metaphysis, usually after a fall on an outstretched hand with hyperextension.

The most widely used classification is the:

Gartland system, ranging from Type I nondisplaced fractures to Type IV multidirectionally unstable injuries.

The most important early concern is:

Neurovascular injury, particularly involving the brachial artery and anterior interosseous, median, radial, or ulnar nerves.

Type I fractures are usually treated with:

Immobilization, whereas displaced unstable Type II, Type III, and Type IV fractures commonly require:

Closed reduction and percutaneous pin fixation.

Major complications include:

Nerve palsy, vascular compromise, compartment syndrome, Volkmann ischemic contracture, cubitus varus, and rare trochlear osteonecrosis.