Intertrochanteric Hip Fracture - Dynamic Hip Screw Technique
- 27244(open treatment of IT, pertrochanteric or subtrochanteric femoral fracture with plate / screw)
- Stable intertrochanteric femur fracture (posteromedial cortex intact/minimal comminution)
- Reverse obliquity IT fracture: use IMHS.
- Unstable IT fracture (posteromedial comminution): use IMHS.
- Nonambulatory with minimal pain / medically unstable
- Nonoperative treatment (early mobilization is key, varus shortened malunion).
DHS Pre-op Planning / Special Considerations
- Generally use 135° 2-hole plate. No biomechanical or clinical advantage has been seen with longer plates (Bolhofner BR, JOT 1999;13:5).
- Ensure tip-apex-distance (TAD) is <25mm. TAD=distance from the tip of the scew to the apex of the femoral head on the A/P view added to that of the lateral view. (Baumgaertner MR, JBJS 1995;77A:1058).
- Use regular length barrel unless fracture line will cross barrel, then consider short barrel. Generaly need >10mm available for sliding. IF using 85mm lag screw or shorter consider using short barrel.
- Add superior derotation screw for basicervical fractures.
- Case Card.
- Pre-operative antibiotics, +/- regional block
- General endotracheal anesthesia
- Supine position on fracture table. Well padded sacral post. All bony prominences well padded. Ensure there is no impingement of the labia or scrotum.
- Fracture reduced under c-arm guidance. Generally gentle longitudinal traction with leg externally rotated followed by internal rotation. Make neck and shaft perpendicular to the perineal post which will make them parallel to the floor and aid in guide wire placement.
- Uninvolved leg is flexed, abducted and externally rotated to allow lateral views with c-arm.
- Ensure there is no residual varus angulation / posterior sag / or malrotation prior to prepping and drapping.
- Prep and drape in standard sterile fashion.
- Use guidewire to draw a line along the anterior hip/thigh in the desired position for the screw.
- Straight lateral incision starting at the vastus ridge and slighlty posterior to the midline
- Elevate vastus lateralis off intermuscular septum.
- Place guide pin in center-center position on both A/P and lateral views within 1cm of subchondral bone using the 135° angle guide.
- Measure screw length.
- Ream femoral neck under c-arm guidance. Ensure pin does not advance.
- Tap the entire screw path to prevent femoral head rotation with screw placement.
- Place plate and impact against lateral cortex. Clamp plate with reduction forceps.
- Release traction. Impact fracture with several taps on leg.
- Insert screws in plate.
- Insert compression screw if there is risk of screw-barrel disengagement (if its difficult to see screw within the barrel). Compression screw is generally not needed.
- Close in layers.
- Screw cut-out: associated with tip-apex distance >25mm, increasing age of the patient, an unstable fracture, a poor reduction, & use of a high-angle (150deg) side-plate
- Loss of fixation
- Malunion (malrotation)
- Osteonecrosis of the femoral head
- Femoral shaft fracture (IMHS)
- Painful hardware
DHS Follow-up care
- Post-op: WBAT. DVT prophylaxis is indicated.
-Time to functional return is faster for patients who are allowed to weight bear early, presumably because those patients unable to maintain a strict non weight bearing status are left in bed for extended periods of time. (Koval KJ, JBJS 1998A;80:357).
-Cognitively intact elderly patients with no other significant comorbidities, stable fracture patterns, and a well placed fixation device should be allowed to be either partially or fully weight bearing within 24-36 hrs after surgery.
-No study has shown immediate weight bearing to contribute to mechanical failure of the implant, however several studies demonstrate that the muscle forces across the hip joint required to maintain a strict non weight bearing status are greater than those with partial or full weight bearing.
-Elderly pts with fragility fractures should be evaluated for osteoporosis.
- 7-10 Days: Wound check, eval reduction on xrays.
- 6 Weeks: Evaluate reduction / fracture union / consolidation on xrays.
- 3 Months:Evaluate reduction / fracture union / consolidation on xrays.
- 6 Months:Evaluate reduction / fracture union / consolidation on xrays.
- 1Yr: Assess outcomes, evaluated xrays for posttraumatic osteonecrosis.
- 2Yr: Assess outcomes, evaluated xrays for posttraumatic osteonecrosis.
- 3Yr: Assess outcomes, evaluated xrays for posttraumatic osteonecrosis.
- After hip fracture the vast majority of patients require assistance in performing ADLs. Only 20% to 35% of patients who were independent in ADLs before fracture will regain their prefracture ADL independence. Factors predictive of recovery of function in ADL are younger age, absence of dementia or delirium in nondemented patients, and a strong social network. (Koval KJ, JAAOS 1994;2:141).
DHS Review References