What is the step-by-step procedure for treating a fracture of the neck of the humerus using Proximal Humerus Internal Locking System (PHILOS) plating?

From the Guidelines

The PHILOS plating procedure for treating a proximal humeral fracture begins with proper patient positioning in the beach chair position under general anesthesia with prophylactic antibiotics administered, as this approach has been shown to provide stable fixation and promote optimal outcomes in terms of morbidity, mortality, and quality of life 1.

Preoperative Preparation

The patient is positioned in the beach chair position to allow for easy access to the shoulder and humerus. General anesthesia is administered, and prophylactic antibiotics are given to minimize the risk of infection.

• The patient's medical history and current medications are reviewed to identify any potential risks or complications.
• Imaging studies, such as X-rays and CT scans, are reviewed to confirm the diagnosis and plan the surgical approach.

Surgical Approach

A deltopectoral approach is used, making an incision from the coracoid process extending distally along the deltopectoral groove.

• The cephalic vein is identified and protected, and the deltopectoral interval is developed.
• The cephalic vein is retracted laterally with the deltoid, and the fracture is exposed by identifying the long head of the biceps tendon as an anatomical landmark.

Reduction and Fixation

Reduction of the fracture is performed using K-wires for temporary fixation, with special attention to restoring the medial calcar and achieving anatomical alignment.

• The PHILOS plate is positioned approximately 5-8mm distal to the greater tuberosity and 2-4mm posterior to the bicipital groove.
• Multiple locking screws are inserted through the plate into the humeral head in divergent directions to enhance fixation, with care taken to avoid intra-articular screw penetration.
• The shaft portion is secured with at least three bicortical screws.

Postoperative Care

Fluoroscopic imaging in multiple planes confirms proper reduction and hardware placement.

• The rotator cuff and subscapularis tendon are repaired if damaged, followed by wound closure in layers.
• Postoperatively, the arm is immobilized in a sling for 2-3 weeks, followed by passive range of motion exercises at 2 weeks and active motion at 6 weeks.
• This technique provides stable fixation through angular stable locking screws that create a fixed-angle construct, particularly beneficial in osteoporotic bone where traditional screws might fail due to poor purchase, as noted in the management of patients older than 50 years with a fragility fracture 1.

From the Research

Step-by-Step Procedure for Treating a Fracture of the Neck of the Humerus using Proximal Humerus Internal Locking System (PHILOS) Plating

• Preoperative planning: Evaluate the patient's fracture using plain radiographs and computed tomography (CT) scans to assess the fracture pattern and displacement 2.
• Patient positioning: Position the patient in a beach chair position to allow for easy access to the shoulder and humerus 2.
• Surgical approach: Use a deltopectoral approach, which has been shown to provide better functional outcomes compared to the deltoid split approach 3.
• Incision and dissection: Make a skin incision and dissect the soft tissues to expose the proximal humerus, taking care to preserve the vascularity of the humeral head 4.
• Reduction and fixation: Reduce the fracture fragments and fix them using the PHILOS plate, which provides stable fixation and eliminates most hardware problems 5.
• Screw insertion: Insert screws into the plate to secure the fracture fragments, using an oblique screw to stabilize the medial column if necessary 2.
• Bone grafting: Bone grafting is not typically necessary, but may be considered in certain cases 2.
• Wound closure: Close the wound in layers, taking care to restore the soft tissues to their normal anatomy 2.
• Postoperative care: Initiate active-assisted and passive exercises of the shoulder on the second postoperative day, and allow active abduction to 90 degrees two weeks after surgery 2.

Potential Complications and Considerations

• Avascular necrosis: Meticulous surgical dissection is necessary to preserve the vascularity of the humeral head and prevent avascular necrosis 4.
• Implant failure: The PHILOS plate has been shown to provide stable fixation and eliminate most hardware problems, but implant failure can still occur 5.
• Malunion: Varus malunion is a potential complication, and careful attention to reduction and fixation is necessary to prevent this 4.
• Infection: Deep infection is a potential complication, and careful wound closure and postoperative care are necessary to prevent this 4.

Outcomes and Results

• Functional outcomes: The PHILOS plate has been shown to provide good functional outcomes, with mean Constant scores ranging from 76.1% to 79.5% 5, 2.
• Complication rates: The complication rate for PHILOS plating is relatively low, with few cases of avascular necrosis, implant failure, and deep infection reported 5, 2, 4.