What is the step-by-step procedure for treating an intertrochanteric femur fracture using Dynamic Hip Screw (DHS) plating?

Dynamic Hip Screw (DHS) Plating for Intertrochanteric Femur Fracture: Step-by-Step Procedure

The Dynamic Hip Screw remains the standard surgical treatment for stable intertrochanteric femur fractures, providing stable fixation that enables early mobilization to reduce morbidity and mortality. 1

Patient Selection and Fracture Assessment

Before proceeding with DHS plating, confirm fracture stability using classification systems:

• Use DHS for stable intertrochanteric fractures (AO/OTA 31-A1 and stable 31-A2 patterns) 2
• Switch to cephalomedullary nailing for unstable fractures, reverse oblique patterns, or subtrochanteric extension 2
• Unstable fractures with severe osteoporosis (Singh grade ≤3) have failure rates exceeding 50% with DHS and should be treated with intramedullary devices instead 3
• Watch for lateral wall comminution or reverse obliquity patterns that indicate instability 4

Preoperative Preparation

Timing and Medical Optimization

• Perform surgery within 24-48 hours of admission to reduce mortality risk 2
• Administer prophylactic antibiotics within one hour of skin incision 5, 1, 2
• Do not use preoperative traction 2

Anesthesia Selection

• Choose either spinal/epidural or general anesthesia—both are equally appropriate 2
• Consider peripheral nerve blocks for enhanced postoperative pain control 1
• Monitor depth of anesthesia with BIS monitoring to avoid cardiovascular depression, particularly in elderly patients 5

Fluid Management and Warming

• Administer preoperative intravenous fluids routinely, as many patients are hypovolemic 5
• Implement active warming strategies intraoperatively and continue postoperatively to prevent hypothermia, especially critical in elderly patients 5, 1
• Use cardiac output-guided fluid administration to optimize outcomes 5

Surgical Procedure: Step-by-Step Technique

Step 1: Patient Positioning

• Position patient supine on a fracture table with the affected leg in traction 4
• Place the unaffected leg in abduction and flexion to allow C-arm access 4
• Avoid excessive flexion and internal rotation of the non-operative hip to prevent pressure damage 5
• Ensure sympathetic positioning to prevent pressure sores and neuropraxia in elderly patients with fragile skin 5

Step 2: C-Arm Setup and Closed Reduction

• Position the C-arm to obtain clear anteroposterior (AP) and lateral fluoroscopic views 4
• Achieve anatomic reduction in the coronal plane without varus angulation before proceeding 4
• Scrutinize for posterior displacement of the fracture, which can occur when supine on the fracture table 4
• Confirm reduction quality on fluoroscopy—reduction quality is more critical than implant choice 4

Step 3: Sterile Preparation and Lateral Hip Approach

• Perform sterile preparation and draping of the operative field 4
• Make a lateral incision centered over the greater trochanter, extending distally along the femoral shaft 4
• Split the tensor fascia lata (TFL) in line with its fibers 4
• Reflect the vastus lateralis anteriorly, controlling bleeding from perforators with 2-0 silk ties rather than cautery alone to prevent recurrent bleeding 4

Step 4: Guide Pin Insertion

• Create a 4.5-mm drill hole in the lateral femoral cortex to allow minor adjustments of the guide pin position 4
• Insert the guide pin under fluoroscopic guidance aiming for the center-center or inferior-center position in the femoral head on both AP and lateral views 4
• Avoid superior placement, which results in poor tip-apex distance and higher screw cut-out rates 4
• Prevent guidewire penetration into the hip joint 4
• Multiple entry attempts can weaken the lateral cortex and propagate fracture into the subtrochanteric region 4

Step 5: Triple-Reaming the Proximal Femur

• Perform sequential reaming over the guide pin using three progressively larger reamers 4
• If the guide pin is inadvertently withdrawn with the reamer, place a lag screw backward in the reamed hole and pass the guide pin back through it 4
• Ensure adequate reaming depth to accommodate the lag screw length 4

Step 6: Sliding Hip Screw Insertion

• Insert the lag screw over the guide pin into the femoral neck and head 4
• Monitor for loss of reduction or femoral head malrotation during lag screw insertion 4
• Confirm optimal screw position with fluoroscopy before final seating 4

Step 7: Side Plate Application and Fixation

• Engage the barrel of the side plate with the sliding hip screw 4
• Contour the plate to the lateral femoral shaft if necessary 4
• Fix the plate to the femur with cortical screws, ensuring bicortical purchase 4
• For unstable 4-part fractures with greater trochanter comminution, consider adding a trochanteric stabilizing plate (TSP) to prevent lateralization and excessive shortening 6

Step 8: Lag Compression Screw (If Appropriate)

• Insert a lag compression screw through the plate if fracture pattern allows for interfragmentary compression 4
• This step is optional and depends on fracture configuration 4

Step 9: Final Fluoroscopic Confirmation and Closure

• Obtain final AP and lateral fluoroscopic images to confirm hardware position and fracture reduction 4
• Irrigate the wound thoroughly 4
• Close the vastus lateralis, fascia lata, subcutaneous tissue, and skin in layers 4
• Use absorbable sutures (such as PDS) for deep layers 4

Postoperative Management

Thromboprophylaxis

• Administer fondaparinux or low molecular weight heparin for DVT prophylaxis 5, 1, 2
• Time low molecular weight heparin administration between 18:00-20:00 to minimize bleeding risk with neuraxial anesthesia 5
• Use thromboembolism stockings or intermittent compression devices 5

Pain Management

• Continue regular paracetamol throughout the perioperative period 5, 1, 2
• Use opioids cautiously, especially in patients with renal dysfunction—reduce both dose and frequency (e.g., halve the dose) 5, 1
• Avoid oral opioids in renal dysfunction; use intravenous routes with dose adjustment 5
• Do not administer codeine due to constipation, emesis, and association with postoperative cognitive dysfunction 5
• Use NSAIDs with extreme caution and avoid in renal dysfunction 5

Mobilization and Rehabilitation

• Implement early mobilization protocols to reduce complications and improve outcomes 1
• Regional anesthesia may facilitate earlier mobilization by reducing DVT risk 5

Common Pitfalls and Complications

Technical Complications to Avoid

• Varus malreduction: Ensure anatomic alignment before fixation 4
• Screw cut-out: Maintain optimal tip-apex distance by avoiding superior screw placement 4
• Lateral cortex weakening: Limit guide pin insertion attempts 4
• Vascular injury: Be aware of profunda femoris artery proximity; pseudoaneurysm formation is rare but serious 7

Implant-Related Issues

• Patients treated with DHS may experience more residual pain and implant irritation compared to intramedullary nailing 8
• By 6 months postoperatively, 91% of stable fractures achieve radiographic union 4
• Monitor for loss of reduction (varus angulation >10°), screw perforation, or >20mm screw extrusion 3

Bone Cement Implantation Syndrome (BCIS)

• Although more relevant to cemented arthroplasty, be aware of hypoxia, hypotension, or loss of consciousness during prosthesis manipulation 5
• Risk reduction includes good surgical technique with medullary lavage and femoral venting 5