Implants and surgical technique

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  Cannulated femoral nail (CFN)

  
  
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  Distal femoral nail (DFN)

  
  
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  Titanium elastic nails (TENs)

Cases

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  Diaphyseal adult femoral fracture (32-A3)

  
  
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  Diaphyseal adult femoral fracture (32-C3)

  
  
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  Diaphyseal children femoral fracture (32-A)

Introduction

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  The Müller AO/OTA Classification divides femoral diaphyseal fractures in adults into three groups:

  
  
  
  
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    32-A: simple—spiral, oblique, or transverse

    
    
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    32-B: wedge—with some continuity between main fragments

    
    
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    32-C: multifragmentary—no continuity between main fragments

  
  
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  Femoral fractures make up 2.5% of all fractures. They mainly occur in three groups of patients:

  
  
  
  
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    Children, as a result of twisting injuries, high-energy direct trauma, or nonaccidental injury

    
    
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    High-energy trauma in young, often male, adults—injuries are usually associated with other injuries

    
    
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    Low-energy trauma in osteopenic bone—usually sustained by the patient in a low-energy fall

  
  
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  Locked intramedullary nailing has revolutionized the management of diaphyseal fractures in adults.

  
  
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  Nails may be inserted antegrade through the piriform fossa, the tip of or the lateral part of the greater trochanter depending on the nail design, or in a retrograde direction through the knee.

  
  
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  While most adult femoral diaphyseal fractures are managed with locked nails, newer plates with locking head screws are gaining popularity in some osteoporotic fractures and are the treatment of choice in periprosthetic fractures.

  
  
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  Plating of the adult femoral shaft with absolute stability has few indications in fresh diaphyseal fractures, but is still widely used in the management of nonunion and malunion.

  
  
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  In the polytraumatized patient (ISS > 17), femoral fractures represent severe life-threatening injuries requiring urgent management and stabilization as early as possible. Patients who are physiologically stable may be managed with early total care and have immediate definitive fixation. In unstable patients a damage-control surgery strategy should be applied with stabilization of the long-bone fractures with external fixators followed by definitive internal fixation after a few days (see chapter 2.9).

  
  
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  In children with open-growth plates intramedullary nailing with “adult-type nails” is not recommended because of the risk of irreversible damage caused to the growth plate by nail insertion leading to growth arrest.

  
  
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  Flexible elastic nails have dramatically changed the management of femoral fractures in children and are the treatment of choice between 3 years and about 14 years.

Müller AO/OTA Classification—diaphyseal femur

3.12.1 Diaphyseal adult femoral fracture (32-A3): stabilization with cannulated femoral nail (CFN)

Surgical management

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  Closed (indirect) reduction and stabilization with cannulated femoral nail (CFN)

Alternative implants

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  Solid (unreamed) femoral nail (UFN)

  
  
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  Distal femoral nail (DFN)

  
  
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  Expert retrograde/antegrade femoral nail (R/AFN)

  
  
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  LC-DCP 4.5 broad or LCP 4.5/5 broad

  
  
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  Large external fixator

1 Introduction

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  Most intramedullary nails in the adult femur fractures are presently inserted in an antegrade direction with reaming of the medullary canal and interlocking.

  
  
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  The nail entry point has traditionally been in the piriform fossa which allows the implant to curve in just one plane—anteriorly.

  
  
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  Newer implants have been developed for a trochanteric (tip or lateral) entry point. The trochanter is easier to reach, particularly in obese patients, but requires the implant to have a proximal lateral bend and an anterior bow. The most recent lateral trochanter entry-point nails (expert lateral femoral nail—LFN) have also incorporated the slightly “corkscrew” shape of the natural femur.

  
  
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  Reaming of the femoral canal is accepted as standard, since there is good evidence that there is less implant failure and a higher and quicker rate of fracture union in comparison with implants inserted without reaming (chapter 2.4.5).

  
  
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  The use of nails inserted without reaming may still be recommended and/or indicated in a polytrauma patient with significant pulmonary injury and/or if the patient is known to have a cardiac shunt (which may be present in up to 25% of the healthy population).

  
  
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  Reamers have deep, sharp flutes to reduce overheating of the canal and subsequent bone necrosis. Some new reamers are even equipped with an irrigation system for direct cooling and an aspiration system to remove bone and marrow debris.

  
  
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  Reamer shafts that are solid and not “wound wire” reduce the incidence of reamer shaft failure or breakage during reaming as well as problems during cleaning and decontamination.

  
  
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  Reamers with solid shafts can be reserved to allow disimpaction of a jammed reamer. Reamers with a “wound wire” shaft must never be reversed as this leads to unwinding of the shaft wires and destruction of the reamer shaft.

2 Preoperative preparation

Operating room personnel (ORP) need to know and confirm:

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  Site and side of fracture

  
  
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  Type of operation planned

  
  
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  Ensure that operative site has been marked by the surgeon

  
  
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  Condition of the soft tissues (fracture: open or closed)

  
  
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  Implant to be used (with or without reaming)

  
  
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  Patient positioning

  
  
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  Details of the patient (including a signed consent form and appropriate antibiotic and thromboprophylaxis)

  
  
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  Comorbidities, including allergies

Instrumentation required:

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  Traction pin set for distal femoral metaphysis (if fracture table is used)

  
  
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  Nailing instrument set—CFN

  
  
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  CFN implant selection

  
  
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  Synream—reamer set

  
  
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  Two reaming rods, long, 1150 mm

  
  
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  Hand reamer set

  
  
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  Large distractor or external fixator (optional)

  
  
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  General orthopaedic instruments

  
  
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  Compatible air or battery drill with attachments

  
  
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  Radiolucent drive

Equipment:

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  Standard radiolucent operating table, which may be reconfigured as fracture table

  
  
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  Table and positioning accessories to assist supine/lateral position and individual position of both legs

  
  
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  Image intensifier

  
  
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  X-ray protection devices for personnel and patient

3 Anesthesia

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  This procedure is performed with the patient under general or regional anesthesia.

  
  
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  Long-lasting postoperative complete pain blocks for the patient with injured leg should be avoided as this could hide symptoms of a subsequent compartment syndrome.

4 Patient and x-ray positioning

Femoral nailing can be performed on a fracture table or on a standard radiolucent table in the lateral position. Both set-up methods are described:

Femoral nailing on a fracture table:

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  The skin of the distal femur is disinfected.

  
  
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  Drill a 2 mm K-wire through the distal femoral metaphysis at the level of the top of the patella (so as not to interfere with distal locking for the nail) and attach a traction bow to it.

  
  
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  Do not use a traction boot on the foot as the foot can slip out.

  
  
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  Reconfigure the table or transfer the patient to a fracture table.

  
  
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  Position the legs at different heights, close together. Alternatively, hang the unaffected leg beneath the affected side or elevate it in a padded gutter out of the way (Fig 3.12.1-2).

  
  
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  If possible reduce the fracture with traction and manipulation before preparing and draping the patient.

  
  
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  Pad all pressure points carefully (especially in the elderly).

  
  
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  Place the ipsilateral arm across the chest to be out of way and keep the upper body “windswept” to adduct the hip as much as possible to aid identifying the nail entry point.

  
  
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  Position the image intensifier on the opposite side of the injury and the operating surgeon.

  
  
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  Ensure that you can get good-quality AP and lateral x-ray views of the entry point (piriform fossa), fracture site, and distal femur before draping.

Femoral nailing on a standard radiolucent table in supine or lateral position:

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  In obese patients it may be technically easier to perform antegrade femoral nailing in a lateral position without skeletal traction.

  
  
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  Place the patient lateral (or supine with a large sandbag under the ipsilateral buttock) on a radiolucent table.

  
  
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  Adduct and slightly flex the affected leg anteriorly in front of the unaffected one.

  
  
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  Position the image intensifier from the opposite side. Check that adequate AP and lateral views can be obtained before draping.