What is the step-by-step procedure for treating a fracture of the lateral end of the clavicle using plating and coracoid process fixation with an Endobutton?

Surgical Procedure for Lateral End Clavicle Fracture with Plating and Coracoid Process Fixation Using Endobutton

The recommended surgical technique for lateral end clavicle fractures is open reduction and internal fixation using a manufacturer-contoured anatomic plate combined with coracoclavicular stabilization using an endobutton device, as this approach provides excellent union rates and functional outcomes with minimal complications. 1

Preoperative Planning

• Obtain upright radiographs to accurately assess the degree of displacement 1
• Evaluate for disruption of the coracoclavicular ligament complex, which is common in lateral clavicle fractures
• Select appropriate implants: manufacturer-contoured anatomic plate and endobutton device with fiber tape/suture material
• Position patient in beach chair position with affected shoulder elevated

Surgical Procedure

Step 1: Approach and Exposure

• Make a curvilinear incision along the superior aspect of the clavicle, centered over the fracture site
• Carefully dissect through subcutaneous tissue, identifying and preserving the supraclavicular nerves
• Expose the fracture site by developing full-thickness skin flaps
• Identify and protect the underlying neurovascular structures

Step 2: Fracture Reduction

• Debride the fracture site of hematoma and interposed soft tissue
• Reduce the fracture anatomically using reduction clamps
• Temporarily hold the reduction with K-wires if necessary

Step 3: Plate Fixation

• Select an appropriate manufacturer-contoured anatomic plate (anterior-inferior positioning is preferred over superior plating to reduce implant removal rates) 1
• Contour the plate to match the anatomy of the lateral clavicle if needed
• Position the plate and secure it with appropriate screws
• Ensure adequate screw purchase in the distal fragment, which is often small and osteoporotic 1

Step 4: Coracoclavicular Fixation with Endobutton

• Identify the coracoid process
• Drill a tunnel from the superior clavicle to the base of the coracoid process
• Pass the endobutton device through the tunnel
• Deploy the endobutton beneath the coracoid process
• Secure the fiber tape/suture to the clavicle, restoring the coracoclavicular distance

Step 5: Closure

• Irrigate the wound thoroughly
• Close the deltotrapezial fascia over the plate
• Close subcutaneous tissue and skin in layers
• Apply sterile dressing and place arm in a sling

Postoperative Management

• Immobilization with a sling is preferred over figure-of-eight bracing 1
• Begin passive range of motion exercises at 2 weeks
• Progress to active range of motion at 6 weeks based on radiographic healing
• Avoid heavy lifting for 3 months

Outcomes and Complications

• This technique produces good functional outcomes with Constant scores averaging 87.1 and DASH scores of 3.3 2
• Union rates are excellent, with most fractures healing within 4-6 months 2, 3
• Potential complications include:
  • Nonunion (risk factors: early mechanical stress, lateral fragment >3cm, delayed surgery) 4
  • Hardware irritation requiring removal
  • Post-traumatic shoulder stiffness 2

Technical Pearls

• Ensure anatomic reduction of the fracture before plate application
• Verify proper positioning of the endobutton beneath the coracoid with fluoroscopy
• Maintain appropriate tension in the coracoclavicular fixation to restore normal anatomy
• The coracoclavicular distance should match that of the contralateral side 5
• Avoid excessive soft tissue stripping to preserve blood supply to the fracture fragments

This technique combines the benefits of plate fixation for direct fracture stabilization with coracoclavicular fixation using an endobutton to address the ligamentous disruption, providing a comprehensive solution for these challenging fractures.