The Emerging Role of Musculoskeletal Ultrasound in Fracture Follow-Up

Radiographic fracture identification and sonographic follow-up assessment.

Introduction

Diagnostic ultrasound is traditionally associated with evaluation of muscles, tendons, ligaments, nerves, and superficial joints.

However, growing evidence suggests that ultrasound may also provide valuable information regarding fracture healing and bone remodeling.

A recent case report followed a distal fibular fracture using serial ultrasound examinations at:

• 2 weeks

• 1 month

• 3 months

• 7 months

demonstrating progressive healing and callus formation over time.  

Why Fracture Follow-Up Matters

Patients often return to activity before complete healing has occurred.

This is particularly relevant for:

• Fibular fractures

• Fifth metatarsal fractures

• Stress injuries

• Athletes returning to sport

Traditionally, monitoring relies on radiography.

However:

• repeated radiation exposure

• cost

• accessibility

remain limitations.  

 Initial AP and oblique radiographs of the right ankle demonstrating a nondisplaced distal fibular fracture at the lateral malleolus with preserved alignment and no evident syndesmotic involvement.

What Can Ultrasound See?

Normal cortical bone appears as:

✔ bright hyperechoic cortical line✔ posterior acoustic shadow

When a fracture occurs:

✔ cortical disruption develops✔ irregularity becomes visible✔ fracture gap may be identified

As healing progresses:

✔ soft callus develops✔ mineralization increases echogenicity✔ cortical continuity gradually returns

This allows ultrasound to visualize the biological healing process in real time.  

Serial musculoskeletal ultrasound examinations of a distal fibular fracture performed at 2 weeks, 1 month, 3 months, and 7 months post-injury. Progressive healing is visualized through reduction of cortical disruption, maturation of callus formation, restoration of cortical continuity, and remodeling of the fracture site over time.

Understanding the Stages of Healing

1. Inflammatory Phase

• hematoma formation

• inflammatory signaling

• cellular recruitment

2. Reparative Phase

• soft callus formation

• fibrocartilage development

• early ossification

3. Remodeling Phase

• woven bone replaced

• cortical architecture restored

• mechanical strength improves

Ultrasound findings evolve alongside these biological stages.

Schematic representation of the biological stages of fracture healing. The process progresses from hematoma formation and inflammation, through fibrocartilaginous callus development and ossification, to final cortical remodeling and restoration of bone structure.

Potential Advantages of Ultrasound

Ultrasound offers several practical advantages:

✔ no ionizing radiation✔ portable✔ relatively inexpensive✔ repeatable serial assessments✔ real-time imaging

Previous studies have even suggested that ultrasound may identify callus formation before radiographic evidence becomes apparent.  

Clinical Implications for Sports Medicine

For sports medicine clinicians, diagnostic ultrasound may provide an additional tool to:

• monitor healing progression

• guide loading decisions

• assess cortical remodeling

• improve patient education

• support return-to-activity discussions

The future role of ultrasound in fracture management may extend beyond diagnosis into longitudinal monitoring.

Conclusion

Diagnostic ultrasound has become an indispensable tool for evaluating soft tissue injuries.

Emerging evidence suggests it may also provide meaningful information regarding fracture healing and bone remodeling.

While radiography remains the standard for fracture diagnosis and follow-up, ultrasound offers a radiation-free, accessible, and dynamic adjunct that may help clinicians monitor healing progression over time.

As ultrasound technology and research continue to evolve, its role in musculoskeletal medicine may extend well beyond tendons and ligaments.