From the Guidelines
Intramedullary (IM) nailing is the recommended treatment for midshaft humerus fractures, and it should be performed as early as possible, ideally within the first 24 hours, to reduce morbidity and mortality, as suggested by the guidelines for acute care of severe limb trauma patients 1. The procedure for IM nailing of midshaft humerus fractures involves several steps:
- Patient positioning: The patient is positioned in either a beach chair or lateral decubitus position under general anesthesia.
- Incision and approach: A 3-5 cm incision is made at the anterolateral acromion for antegrade nailing or at the distal humerus for retrograde approach.
- Access to the fracture site: The rotator cuff is split (for antegrade) or the triceps is split (for retrograde) to access the entry point.
- Guide wire insertion: A guide wire is inserted under fluoroscopic guidance through the fracture site to the opposite end of the humerus.
- Reaming and nail insertion: The medullary canal is reamed incrementally to 1mm larger than the planned nail diameter, typically 7-9mm, and the appropriate length nail is inserted over the guide wire.
- Interlocking screws: Interlocking screws are placed proximally and distally to prevent rotation, typically two screws at each end using a targeting device.
- Wound closure: The incision is irrigated with normal saline, and the rotator cuff or triceps is repaired with absorbable sutures, followed by skin closure with subcuticular stitches or staples.
- Postoperative care: Patients receive prophylactic antibiotics (often cefazolin 1g IV) for 24 hours and appropriate pain management, and physical therapy begins with pendulum exercises at 2 weeks, progressing to active range of motion at 4-6 weeks, as recommended by the guidelines for acute care of severe limb trauma patients 1. The key to successful IM nailing is to perform the procedure as early as possible, while ensuring the patient's clinical status is stable, to minimize the risk of systemic complications and promote faster healing, as emphasized by the guidelines 1.
From the Research
Step-by-Step Procedure for Treating a Midshaft Humerus Fracture with Intramedullary (IM) Nailing
- Preoperative preparation: The patient is positioned on a radiolucent table to allow for fluoroscopic imaging during the procedure 2.
- Approach: The approach for IM nailing of the humerus can be either antegrade (through the shoulder) or retrograde (through the elbow) 3.
- Reduction: The fracture is reduced, and the nail is inserted into the medullary canal of the humerus 4.
- Nail placement: The nail is advanced into the distal fragment, and the proximal fragment is reduced onto the nail 5.
- Locking: The nail is locked in place with screws or bolts to stabilize the fracture 6.
- Confirmation: Fluoroscopic imaging is used to confirm the correct placement of the nail and the reduction of the fracture 2.
Potential Complications and Considerations
- Radial nerve palsy: This is a potential complication of IM nailing, especially with antegrade approaches 2, 3.
- Nonunion: This is a potential complication of IM nailing, although the risk is similar to that of plate fixation 3, 5.
- Shoulder stiffness: This is a potential complication of IM nailing, especially if the nail is not properly positioned or if the patient does not undergo adequate rehabilitation 5.
- Infection: This is a potential complication of any surgical procedure, including IM nailing 2, 5.
Comparison with Plate Fixation
- IM nailing and plate fixation have similar union rates and complication rates 3, 5.
- Plate fixation may be associated with better shoulder function and reduced pain, but also has a higher risk of nerve injury and reoperation 5.
- The choice of fixation method should be tailored to the individual patient and fracture characteristics 6.