Cephalomedullary Nail Insertion Procedure
Cephalomedullary nail insertion is a relatively straightforward intramedullary nailing procedure performed under general or regional anesthesia, requiring careful attention to entry portal location, guide wire placement, and reduction maintenance throughout the procedure. 1
Preoperative Assessment and Planning
Critical preoperative imaging of the entire femur is mandatory to identify any proximal lesions (particularly femoral neck pathology) that could lead to implant failure or necessitate alternative fixation strategies. 1, 2 A long bone survey or bone scan within 2-3 months is recommended when treating pathologic fractures to detect other disease sites that may affect weight-bearing. 1
Key preoperative assessments include: 1
- Life expectancy estimation
- Mental and mobility status
- Pain level and metabolic status
- Skin condition and nutritional status
- Renal function (affects anesthetic and analgesic choices)
Anesthesia and Patient Positioning
Either spinal or general anesthesia is appropriate with no clear preference. 3 Prophylactic antibiotics must be administered within one hour of skin incision. 3
Position the patient carefully to avoid excessive flexion and internal rotation of the non-operative hip, which can cause pressure damage, particularly in elderly patients with fragile skin. 3
Surgical Technique: Key Steps
Entry Portal Location
Locating the correct entry portal is technically challenging and critical for success. 4 The entry point is typically at or slightly medial to the tip of the greater trochanter, accessed through a small proximal incision.
Guide Wire Insertion
The most common technical difficulty is preventing the guide wire from deviating superiorly away from the femoral calcar. 5
To achieve proper guide wire placement: 5
- Once the guide wire passes through the tack hole of the nail, slightly tap the nail rod down further
- Allow the superior border of the tack hole to contact the guide wire, using it as a presser to prevent upward deviation
- This directs the wire toward the femoral calcar rather than the superior femoral head
- After proper positioning, pull the nail rod back slightly to center the wire in the tack hole
Reaming and Nail Insertion
Small femoral canal size is a critical factor that can cause reduction loss during nail insertion. 6 In patients with narrow canals:
- Consider reaming the isthmus before nail insertion 6
- Alternatively, select a smaller diameter cephalomedullary nail 6
- External rotation of the intramedullary nail during insertion reduces malreduction risk in bowed femurs 2
The nail should be inserted carefully to avoid: 4
- Driving the nail through the intercondylar notch
- Causing reduction loss of the entire proximal fragment (not just the superolateral femoral neck) 6
Reduction Maintenance
Patients with smaller femoral canal size experience increased calcar distance and poorer reduction quality. 6 Maintain anatomic reduction throughout the procedure, as reduction loss during nail insertion is common and leads to increased corrected neck-shaft angles that tend to worsen during follow-up. 6
Proximal Locking
Insert the lag screw or helical blade through the tack hole, ensuring it: 5
- Achieves good purchase at the femoral calcar
- Reaches within 5-10mm of subchondral bone
- Avoids placement in the superior femoral head
Distal Locking
Static locking is typically performed in most cases. 7 Ensure proper distal screw placement to prevent nail migration or backing out of proximal screws. 4
Technical Pitfalls to Avoid
The procedure requires a high degree of accuracy and technical expertise with a definite learning curve. 4, 8 Common complications include: 4
- Proximal screw loosening and backing out (occurs when calcar purchase is inadequate)
- Malreduction requiring revision surgery 8
- Nail fracture (rare but catastrophic)
- Cutting out of screws in the femoral head
Postoperative Considerations
The procedure typically requires a hospital stay of approximately 2 days. 1 Immediate postoperative management includes: 3
- DVT prophylaxis with fondaparinux or low molecular weight heparin
- Regular paracetamol for pain control
- Cautious opioid use, especially in renal dysfunction
- Early mobilization protocols with immediate weight-bearing as tolerated
Case series demonstrate excellent outcomes with complete pain relief and resumption of ambulation in a large proportion of patients, though these results may reflect careful patient selection. 1