Dynamic Hip Screw (DHS) Plating for Intertrochanteric Femur Fractures: Step-by-Step Surgical Procedure
Critical Pre-Procedure Decision: Is DHS the Right Implant?
DHS plating should only be used for STABLE intertrochanteric fractures; unstable fractures, subtrochanteric fractures, and reverse obliquity patterns require cephalomedullary nail fixation instead. 1
- Stable fractures suitable for DHS include two-part fractures with intact posteromedial cortex and lesser trochanter 2, 3
- Unstable patterns requiring intramedullary nailing include comminuted fractures, reverse obliquity patterns, subtrochanteric extension, and fractures with posteromedial comminution 1, 3
- DHS is contraindicated in pathologic fractures, particularly when subsequent radiation is planned, due to lack of bone healing 2
Preoperative Preparation
Timing and Medical Optimization
- Surgery must be performed within 24-48 hours of admission to optimize outcomes and reduce mortality 2, 4
- Administer prophylactic antibiotics within one hour of skin incision to reduce surgical site infections 2, 4
- Do NOT use preoperative traction—this has no benefit and is specifically not recommended 1, 2
Anesthesia Selection
- Either spinal or general anesthesia is appropriate with no clear preference, though spinal may reduce postoperative confusion in elderly patients 2, 4
- Monitor depth of anesthesia with BIS monitoring to avoid cardiovascular depression in elderly patients 2
Pain Management Strategy
- Perform multimodal analgesia including peripheral nerve block (iliofascial block) in the emergency department or preoperatively 1
- Continue regular paracetamol throughout the perioperative period 2
Fluid and Temperature Management
- Administer preoperative intravenous fluids routinely, as many patients are hypovolemic; use cardiac output-guided fluid administration 2
- Implement active warming strategies intraoperatively and continue postoperatively to prevent hypothermia 2
Patient Positioning
- Position patient supine on a fracture table with the affected leg in traction 3
- Apply gentle traction to achieve length and alignment 5
- Position the unaffected leg in abduction and flexion to allow C-arm access 3
- Avoid excessive flexion and internal rotation of the non-operative hip to prevent pressure damage 2
- Ensure meticulous padding of all bony prominences to prevent pressure sores and neuropraxia, especially critical in elderly patients with fragile skin 2, 4
Surgical Approach and Exposure
Incision and Dissection
- Make a lateral incision centered over the greater trochanter, extending proximally and distally (typically 8-12 cm) 3
- Incise the fascia lata in line with the skin incision 3
- Split the vastus lateralis muscle fibers longitudinally or elevate anteriorly to expose the lateral femoral cortex 3
- Identify and protect the vastus lateralis ridge on the lateral femur 3
Fracture Reduction
Reduction Technique
- Achieve reduction using closed techniques with traction and internal rotation on the fracture table 5, 3
- Confirm reduction with AP and lateral fluoroscopic views before proceeding 5
- Anatomic reduction of the posteromedial cortex is critical to prevent varus collapse 5, 3
- If closed reduction fails, perform limited open reduction to restore the posteromedial buttress 5
- Proper fixation of the lesser trochanter and posteromedial bone fragments is essential to prevent complications 5
Common Pitfall
- Inadequate reduction, particularly varus malalignment or persistent posteromedial comminution, is a major cause of fixation failure 5, 3
Guide Wire Placement
Critical Technical Point: Wire Position Determines Success
- Insert a guide wire from the lateral femoral cortex into the femoral head under fluoroscopic guidance 6, 3
- The guide wire MUST be positioned in the postero-inferior and central position within the femoral neck and head on both AP and lateral views 6
- Anterior or superior positioning of the screw produces higher incidence of cut-out failure 6
- The ideal position is center-center or slightly inferior-posterior on both views 6, 3
- Aim for the guide wire tip to be within 5-10 mm of the subchondral bone of the femoral head 3
- Confirm position with perfect AP and lateral fluoroscopic images before proceeding 6, 5
Lag Screw Insertion
Reaming and Screw Placement
- Ream over the guide wire using the triple reamer system to create a path for the lag screw 3
- Measure the appropriate lag screw length using the calibrated guide wire or depth gauge 3
- Insert the lag screw over the guide wire to the predetermined depth 3
- The lag screw tip should be positioned within 5-10 mm of the subchondral bone but not penetrate the femoral head 6, 3
- Confirm final screw position with fluoroscopy in both AP and lateral views 6, 5
Critical Warning
- Screw penetration through the femoral head is a major complication occurring in up to 16.7% of cases when positioning is suboptimal 6
Barrel Plate Application
Plate Selection and Fixation
- Select the appropriate barrel plate length based on bone quality and fracture pattern (typically 4-hole or 5-hole plate) 3
- Slide the barrel plate over the lag screw and position it flush against the lateral femoral cortex 3
- Ensure the barrel is seated properly on the lag screw 3
- Insert the compression screw into the barrel to lock the lag screw to the plate 3
- Apply controlled compression by tightening the compression screw, allowing the lag screw to slide within the barrel 3
Distal Screw Fixation
- Insert cortical screws through the remaining plate holes into the femoral shaft 3
- Use at least 4 cortical screws in the distal fragment for adequate fixation 3
- Ensure bicortical purchase with all screws 3
- Confirm all screws are properly seated with fluoroscopy 5
Final Verification
Fluoroscopic Confirmation
- Obtain final AP and lateral fluoroscopic images to confirm 5:
- Adequate fracture reduction with restoration of the posteromedial cortex
- Lag screw position in the postero-inferior and central location within the femoral head
- Appropriate screw tip-to-subchondral bone distance (5-10 mm)
- No screw penetration of the femoral head
- Proper plate position and all screws adequately seated
Common Technical Errors to Avoid
- Nonstandard operative procedure and unsatisfactory reduction are major causes of complications 5
- Varus deformity occurs when posteromedial support is not restored 5
- Proximal femoral cortex fracture can occur during reaming or screw insertion if technique is not meticulous 5
Wound Closure
- Irrigate the wound copiously 4
- Close the vastus lateralis and fascia lata in layers 4, 3
- Close subcutaneous tissue and skin 4
- Apply sterile dressing 4
Postoperative Management
Immediate Postoperative Care
- Allow immediate weight-bearing as tolerated 1
- Implement early mobilization protocols to reduce complications 2
- Continue regular paracetamol for pain control 2
- Use opioids cautiously, especially in patients with renal dysfunction; avoid codeine due to constipation, emesis, and association with postoperative cognitive dysfunction 2
- Avoid NSAIDs in patients with renal dysfunction 2
Thromboprophylaxis
- Administer fondaparinux or low molecular weight heparin for DVT prophylaxis 2, 4
- Use sequential compression devices while hospitalized 1
- Continue pharmacologic prophylaxis for 4 weeks postoperatively 1
- Time low molecular weight heparin administration between 18:00-20:00 to minimize bleeding risk with neuraxial anesthesia 2
Blood Management
- Transfuse for symptomatic anemia (fatigue, hypotension) 1
- Use a transfusion threshold no higher than 8 g/dL in asymptomatic patients 1
Bone Health
- Order outpatient DEXA scan and refer to bone health clinic for osteoporosis evaluation and treatment 1
- Draw vitamin D, calcium, and parathyroid hormone levels while hospitalized 1
Complications and Prevention
Major Complications
- Screw cut-out through femoral head and neck (16.7% incidence) is prevented by optimal screw positioning in the postero-inferior and central location 6
- Varus deformity (occurs in up to 38% of complicated cases) is prevented by anatomic reduction and restoration of posteromedial support 5
- Femoral head necrosis is rare but can occur 5
- Wound infection (up to 23% of complications) is prevented by meticulous sterile technique and appropriate perioperative antibiotics 4, 5
- Nonunion is prevented by adequate reduction, proper fixation, and avoiding too early weight-bearing 5