Orthopaedic Surgery - Metatarsal Fracture

Basics

Metatarsal fractures are fractures of the forefoot metatarsal bones and may involve the head, neck, shaft, or base.

They may result from:

Acute trauma, inversion injury, repetitive overuse, or abnormal foot mechanics.

Stress fractures most commonly involve the second and fifth metatarsals.

Classification

Metatarsal fractures can be classified according to:

Anatomic location

Traumatic versus stress mechanism

Specific fifth-metatarsal fracture pattern

Metatarsal Head, Neck, and Shaft Fractures

These fractures may result from:

Direct impact, axial loading, crush trauma, or twisting injury.

The degree of displacement and especially the sagittal alignment are important in determining treatment.

Stress Fractures

Metatarsal stress fractures result from repeated loading that exceeds the bone’s ability to remodel.

They occur most frequently in:

The second metatarsal

and

The fifth metatarsal.

They are especially common after a sudden increase in running, marching, or other repetitive weight-bearing activity.

Fifth Metatarsal Fractures

Proximal fifth-metatarsal fractures are particularly important because prognosis and treatment vary according to location.

Avulsion Fracture

An avulsion fracture involves the tuberosity at the proximal fifth metatarsal.

It is often called a pseudo-Jones fracture.

These fractures generally have good healing potential.

Jones Fracture

A Jones fracture occurs at the metaphyseal-diaphyseal junction of the fifth metatarsal.

This region has a relatively poor blood supply and therefore carries an increased risk of:

Delayed union and nonunion.

Jones fractures are generally less stable than tuberosity avulsion fractures.

Diaphyseal Stress Fracture

Stress fractures may also develop more distally in the proximal fifth-metatarsal diaphysis.

They are commonly associated with repetitive loading and may behave like chronic stress injuries with delayed healing.

Synonyms

Terms used in this group of injuries include:

Jones fracture

Pseudo-Jones fracture

Stress fracture

March fracture

Prevention

Preventive measures include:

Avoiding unnecessary foot trauma

Increasing running or training volume gradually

Avoiding abrupt changes in exercise intensity

Using appropriate footwear

Replacing excessively worn running shoes

Training errors should be corrected when stress injury is suspected.

Epidemiology

Metatarsal fractures occur in:

Both males and females and across all age groups.

They are among the more common fractures of the foot.

Athletes

Fifth-metatarsal fractures are particularly common in athletes involved in:

Running, jumping, cutting, and pivoting sports.

Osteoporosis

Metatarsal fractures are also common in individuals with reduced bone density, particularly:

Older women with osteoporosis.

Risk Factors

Important risk factors include:

Sudden increase in training volume

Repetitive impact loading

High-level athletic activity

Abnormal biomechanics

Osteoporosis

Poorly conditioned bone

Etiology

The major mechanisms include:

Direct trauma

Inversion injury

Repetitive overuse

Axial loading

Direct Trauma

A direct blow or crush injury may produce:

Metatarsal head, neck, or shaft fractures, sometimes involving multiple rays.

Inversion Injury

An inversion mechanism commonly produces an avulsion fracture at the base of the fifth metatarsal.

The peroneus brevis and lateral plantar structures may contribute to the avulsion force.

Overuse

Stress fractures result from repeated loading before sufficient bone remodeling can occur.

This commonly follows:

Rapid increases in running distance, marching, jumping, or other repetitive activity.

Associated Conditions

Metatarsal fractures may occur with:

Lisfranc injury

Other midfoot fractures

Rarely, compartment syndrome

Multiple fractures should increase suspicion for a more complex forefoot or midfoot injury.

Diagnosis

Signs and Symptoms

Typical findings include:

Pain

Swelling

Ecchymosis

Deformity

Difficulty bearing weight

Localized tenderness over the involved metatarsal

Stress Fracture Symptoms

Stress fractures often present more gradually with:

Activity-related pain that becomes progressively more persistent.

Early in the course, pain may disappear with rest.

History

Important historical information includes:

Direct trauma

Inversion mechanism

Crush injury

Recent increase in training

Running or marching volume

Previous stress fracture

Bone-health risk factors

Physical Examination

The examination commonly demonstrates:

Point tenderness directly over the involved metatarsal.

Swelling

Acute fractures may cause marked swelling of the entire forefoot.

Bruising may occur on the:

Dorsal, plantar, or lateral aspect of the foot.

Alignment

Inspect for:

Angular deformity

Forefoot widening

Loss of normal metatarsal alignment

Associated midfoot deformity

Neurovascular Examination

Document:

Distal sensation

Toe motor function

Capillary refill

Pedal pulses

Skin Examination

Open wounds, severe swelling, or skin tenting should be identified because they may alter urgency and treatment.

Imaging

Plain Radiographs

Plain radiographs are usually diagnostic.

Standard views include:

AP

Lateral

Oblique

foot radiographs.

Lateral View

The lateral radiograph is particularly important because sagittal displacement or angulation can lead to abnormal plantar loading.

Occult Stress Fracture

Early stress fractures may not appear on initial radiographs.

If clinical suspicion remains high, additional imaging may include:

MRI

or, less commonly,

Bone scintigraphy.

MRI is particularly useful because it can identify:

Bone marrow edema and an early fracture line.

Pathological Findings

Acute fractures demonstrate:

Cortical and trabecular disruption with hematoma formation.

With healing, callus forms and gradually remodels.

Delayed Union and Nonunion

Chronic fifth-metatarsal injuries, particularly Jones and proximal diaphyseal stress fractures, may demonstrate:

Sclerosis

Widening of the fracture line

Delayed callus

Nonunion

Differential Diagnosis

Important alternatives include:

Soft-tissue contusion

Foot sprain

Lisfranc injury

Tendon injury

Stress reaction without complete fracture

Treatment

General Principles

Treatment depends on:

Fracture location

Displacement

Angulation

Number of involved metatarsals

Articular involvement

Patient activity level

Healing potential

Isolated Neck or Shaft Fractures

Stable isolated fractures can often be managed with:

A stiff-soled or postoperative shoe, walking boot, or short-leg cast.

Weight bearing is usually permitted as tolerated if the fracture pattern is stable.

Immobilization

Immobilization commonly lasts approximately 3–4 weeks, followed by transition to:

A supportive, well-padded shoe.

Unnecessarily prolonged casting should be avoided because it can contribute to stiffness and deconditioning.

Reduction

Closed reduction may be required when there is:

More than approximately 10° of significant angulation, unacceptable displacement, or malalignment.

Some unstable fractures require percutaneous stabilization after reduction.

Importance of Sagittal Alignment

Sagittal-plane alignment is particularly important.

A malunited metatarsal that heals excessively:

Plantarflexed or dorsiflexed

may alter forefoot loading.

This can result in:

Transfer metatarsalgia, plantar pain, or dorsal shoe irritation.

Transverse Displacement

Some transverse-plane displacement of the central second through fourth metatarsals may be tolerated if:

Length, sagittal alignment, and rotation remain acceptable.

First and Fifth Metatarsals

Alignment of the first and fifth metatarsals is more critical because these rays form the medial and lateral borders of the forefoot.

Malalignment may cause:

Abnormal weight bearing or difficulty with shoe wear.

Multiple Metatarsal Fractures

Multiple fractures are more likely to be unstable.

They may require:

Open reduction and internal fixation or percutaneous pinning.

Restoration of the normal metatarsal parabola and forefoot architecture is important.

Metatarsal Head Fractures

Metatarsal head fractures are uncommon and usually result from direct trauma.

Closed reduction may be successful when displacement is limited.

If reduction is unstable, fixation may be required to restore:

Articular congruity and alignment.

Fifth-Metatarsal Avulsion Fractures

Most tuberosity avulsion fractures heal successfully with:

A stiff-soled shoe, walking boot, or symptomatic support.

Weight bearing is typically advanced according to pain.

Jones Fracture

Jones fractures require more cautious treatment because of their elevated risk of delayed union and nonunion.

Nonoperative Treatment

A nondisplaced Jones fracture may be managed with:

Immobilization and restricted or non-weight bearing, often for approximately 6–8 weeks depending on healing.

Displacement

Historically, displacement greater than approximately 2 mm has been considered an indication for operative stabilization.

Athletes and Highly Active Patients

Because faster and more predictable union is desirable, surgical fixation is frequently considered for:

Competitive athletes and highly active individuals, even with minimally displaced acute Jones fractures.

Stress Fractures

Metatarsal stress fractures are initially managed with:

Activity modification and protection from repetitive loading.

A boot, cast, or orthosis may be used when pain is substantial.

Relative rest commonly lasts at least 3–4 weeks, but return to activity should depend on clinical healing.

Pediatric Considerations

Physeal injuries of the metatarsals are uncommon but can occur when:

The growth plate or epiphysis is involved by avulsion or fracture.

Treatment

Stable pediatric injuries can generally be treated with:

A below-the-knee walking cast or boot for approximately 3–4 weeks.

Growth Disturbance

Significant growth inhibition is uncommon.

When growth disturbance occurs, relative overgrowth has historically been observed more often than major shortening.

Physical Therapy

Routine formal physical therapy is not required for most uncomplicated metatarsal fractures.

Once healing has occurred, most patients regain normal daily function without difficulty.

Rehabilitation

When needed, rehabilitation may emphasize:

Ankle and toe motion

Strength

Balance

Progressive gait training

Gradual return to running and sport

Medication

Analgesia is used as needed.

Common options include:

Acetaminophen and other appropriate pain medications.

Older teaching discouraged NSAIDs because of concern about possible effects on fracture healing; in clinical practice, the significance of short-term NSAID use remains debated and should be individualized.

Surgery

The objective of surgery is to restore the weight-bearing architecture of the forefoot while permitting reliable healing.

Surgical Indications

Possible indications include:

Unacceptable shortening

Sagittal displacement

Malrotation

Unstable multiple metatarsal fractures

Displaced intra-articular fractures

Open fractures

Delayed union or nonunion

High-risk Jones fractures

Shortening and Elevation

Historically, approximately 2–4 mm of shortening or dorsal elevation of the central metatarsals has been used as a relative threshold for considering operative correction.

Less deformity is typically accepted in the first and fifth rays because malalignment there more directly alters forefoot function.

Open Reduction and Internal Fixation

Fixation options include:

Plates and screws

Intramedullary K-wires

Percutaneous pins

Intramedullary screws

Choice depends on fracture location and pattern.

Plate Fixation

Metatarsal shaft fractures may be stabilized through a dorsal approach using a small plate and screws.

The goal is to restore:

Length, rotation, and sagittal alignment.

Intramedullary Kirschner Wires

K-wires can be passed intramedullary through the metatarsal and may exit distally through the toe.

They are particularly useful for selected:

Neck, shaft, and multiple metatarsal fractures.

Jones Fracture Fixation

Jones fractures are often stabilized using a long intramedullary screw.

This provides compression and stability across the fracture.

Postoperative Weight Bearing

After stable operative fixation of a Jones fracture, weight bearing may be advanced gradually according to:

Pain, radiographic healing, fracture characteristics, and surgeon protocol.

Nonunion

Symptomatic nonunion may require:

Débridement of nonviable or sclerotic bone

Correction of malalignment

Stable fixation

Possible bone grafting

Bone Grafting

Bone graft may be particularly useful for:

Chronic stress fractures, established nonunion, or bone loss.

Follow-Up

Patients commonly benefit from:

Crutches, a walker, or another walking aid during the early postinjury period.

Radiographic Follow-Up

After reduction, radiographs are often obtained at approximately:

1 week to confirm maintenance of alignment.

Additional imaging is commonly performed around:

4–6 weeks, depending on fracture type and symptoms.

Healing Assessment

Radiographic healing is suggested by:

Callus formation and progressive disappearance of the fracture line.

Clinical healing is suggested when:

Local tenderness has resolved and weight bearing is comfortable.

Prognosis

The prognosis is generally good when:

Sagittal alignment is preserved and union occurs uneventfully.

Jones Fracture Prognosis

Jones fractures have a less predictable course because of the vascular characteristics of the metaphyseal-diaphyseal junction.

Delayed union and nonunion are more common than with simple fifth-metatarsal tuberosity avulsion fractures.

Complications

Potential complications include:

Transfer metatarsalgia

Delayed union

Nonunion

Malunion

Forefoot pain

Difficulty with shoe wear

Neuroma symptoms

Post-traumatic arthritis in articular fractures

Transfer Metatarsalgia

If one metatarsal heals too short or abnormally elevated, pressure may be transferred to adjacent metatarsal heads.

This can produce:

Painful plantar overload and callus formation.

Patient Monitoring

Follow-up should assess:

Pain

Tenderness

Weight-bearing tolerance

Alignment

Radiographic healing

Return to normal gait

Return to Activity

Full activity should resume only when the patient demonstrates:

Minimal or no tenderness

Pain-free walking

Adequate strength

Appropriate radiographic healing when indicated

For stress fractures and Jones fractures, return to running and sport should be gradual to reduce the risk of recurrence.

Key Principle

The most important objectives in treating metatarsal fractures are to preserve:

Metatarsal length, sagittal alignment, forefoot width, and normal weight distribution.

Particular attention should be given to Jones fractures, because their location predisposes them to delayed union and nonunion.