A detailed history and physical examination should be performed. Many patients with femur fractures have serious associated limb or life-threatening injuries. Patients with femoral shaft fractures should be evaluated using the Advanced Trauma Life Support (ATLS) protocols to ensure that shock and other critical injuries are identified and treated. A multidisciplinary approach is required in the multiply injured patient to optimize patient care. Virtually all patients with an acute femur fracture have a very painful leg that is swollen. The limb is usually shortened and externally rotated. Motion of the affected hip and knee is resisted secondary to pain. The condition of the soft tissues and limb compartments as well as the neurovascular status should be evaluated and clearly documented. If orthopedic surgery is delayed >12 hours, a skeletal traction pin through the distal femur or proximal tibia is indicated to relieve pain and restore limb length. Isolated femoral shaft fractures should be treated within 12 to 24 hours whenever possible. Open fractures require emergent irrigation and débridement with fracture stabilization with a nail or temporary external fixator.

Full-length AP and lateral radiographs of the entire femur are mandatory. Dedicated x-rays of the hip and knee are often required to rule out intercondylar extension or an ipsilateral femoral-neck fracture based on the clinical exam and initial x-rays. Computerized tomography (CT) of the knee is recommended in patients with supracondylar femur fractures to rule out an unrecognized intercondylar split or coronal plane fracture of the femoral condyle (Hoffa fracture). Most trauma patients undergo CT scanning of their abdomen and pelvis as part of the ATLS protocol. These scans should be carefully reviewed to assess the integrity of the hip and rule out an occult femoral neck fracture. In comminuted and displaced fractures, traction views or fluoroscopic radiographs in the operating room, with the patient anesthetized, may be helpful in clarifying the fracture geometry or to identify subtle injuries to the hip or knee joint.

Full-length films are necessary to allow measurement of the length and diameter of the femur. Patients of small stature, persons of Asian descent, and those with developmental problems often have very narrow canals. Most manufacturers do not make retrograde nails smaller than 9 or 10 mm in diameter. This must be recognized prior to surgery so that either a nail of appropriate diameter is available or other surgical options are considered. It is important to ensure that there is a full complement of nails available at the time of surgery. Many studies have shown that the best results following retrograde femoral nailing are achieved when a full-length canal fill nail is utilized.

The decision to use a percutaneous or limited open approach for nail insertion is dictated by the status of the distal femoral fragment. When it is intact, a percutaneous approach is preferred. If the distal fragment is displaced with fracture extension into the knee joint, a more extensile approach is usually necessary. Occasionally, a nondisplaced split between the femoral condyles can be treated with independent cannulated screws inserted through small stab incisions laterally. The presence of an intra-articular split in the femoral condyles should be a major priority when planning the approach. Visualization and fixation of the articular surface may be compromised by an incorrectly placed incision. Cannulated screws of similar metallurgy to the retrograde nail should be used as well as any hardware if an associated hip fracture is present. In a patient with an ipsilateral femoral-neck fracture, important decisions must be made prior to surgery about the type of table and patient position for this combined injury. In patients with other extremity fractures, preoperative planning is necessary for positioning and draping to optimize resources.

Intramedullary nailing is usually performed under general anesthesia, but in isolated injuries particularly in the elderly with medical comorbidities, a spinal may be preferable. We prefer general anesthesia because it allows predictable muscle paralysis for fracture reduction and fixation. Preoperative antibiotics, usually a first-generation cephalosporin, are administered and continued for 24 hours postsurgery. Vancomycin or clindamycin is used in patients with penicillin allergies. Arterial lines, central venous catheters, and the need for a Foley catheter are inserted on a case-by-case basis.

Retrograde femoral nailing is performed with the patient supine on a radiolucent table. Some surgeons prefer a bolster beneath the torso, but care must be taken to avoid excessive pelvic obliquity that can lead to rotational errors. The optimal position for nailing is with the patient supine and the patella pointing straight upward. The limb is sterilely prepped and draped from the toes to the iliac crest. It is important to have the entire leg exposed to allow for evaluation of length and rotation as well as for placement of the proximal anterior-posterior locking screws (Fig. 23.2).

The ability to flex the knee between 40 and 50 degrees is very important. Too little knee flexion does not allow correct position of the guide pin or passage of the reamers and nail. Furthermore, inadequate knee flexion risks damage to the tibial plateau from contact with the instruments (Fig. 23.3). Too much knee flexion makes radiographic visualization of the distal-femoral entry site difficult and puts the patella in the way of the insertion, which can lead to articular damage. Protection sleeves should always be used to minimize injury to the patellar tendon or tibial plateau. We favor the use of sterile radiolucent triangles to maintain precise knee flexion during the case. If this is not available, a sterile bolster can be used.

For the percutaneous approach, a 2- to 3-cm incision is made just medial to the patellar tendon. Alternatively, a patellar tendon-splitting approach can be used. The joint capsule is opened, and the fat pad and synovium are bluntly dissected in the intercondylar region with a scissors or long hemostat. With the C-arm in the anterior-posterior and tilted 20 degrees cephalad, a trochar-tipped guide pin is positioned in the center of the
intercondylar notch. On the lateral view, the guide pin is centered just anterior to the tip of the inverted V formed by Blumensaat’s line and the femoral groove (Fig. 23.4A,B). The guide pin is then advanced 4 to 5 cm into the distal femoral metaphysis under fluoroscopic control to ensure that the pin is centered in both projections. The distal femur is then opened with a cannulated 12-mm straight reamer while the patellar tendon is protected with retractors or a sleeve (Fig. 23.5). The guide pin is then removed.

A 3.2-mm ball-tipped guide wire with a slight bend at the tip is inserted into the opening in the distal femur. The fracture is reduced by strong longitudinal traction with muscle paralysis. Once the length is restored, alignment can be improved by positioning sterile bolsters under the thigh or using external devices to apply force. When traction alone does not reduce the fracture, percutaneous insertion of 5-mm self-drilling Schanz pins proximally and distally is a simple and expedient technique of reduction that restores length and allows passage of the guide wire (Fig. 23.6A,B). Alternatively, a strategically placed femoral distractor may be helpful in comminuted fractures to maintain length during reaming and nail placement or when a scrubbed assistant is unavailable. When a distractor is used, the most distal pin is placed distal and anterior in the distal fragment at the level of the epiphyseal scar to allow unimpeded passage of the reamers and the nail. The proximal pin is placed as proximal as possible, usually
just proximal to the lesser trochanter, to allow unimpeded reamer and nail passage (Fig. 23.7). The femoral distractor should be placed with the distraction rod anterolateral to allow for distal interlocking with the distractor in place. Another technique for reduction is to place an intramedullary reduction device over the guide rod in the distal fragment, manipulate the fracture, and pass the guide rod retrograde to the intertrochanteric region of the femur.