Summary Femoral shaft fractures are high energy injuries to the femur that are associated with life-threatening injuries (pulmonary, cerebral) and ipsilateral femoral neck fractures. Diagnosis is made radiographically with radiographs of the femur as well as the hip to rule out ipsilateral femoral neck fractures. Treatment generally involves intramedullary nailing which is associated with >95% union rates. Epidemiology Incidence common 37.1 per 100,000 person annually Etiology Mechanism traumatic high-energy login to view 2 more bullets low-energy login to view 3 more bullets Fracture patterns transverse pure bending moment spiral rotational moment oblique uneven bending moment segmental 4-point bending moment comminuted high-speed crush or torsion mechanism Associated conditions orthopaedic ipsilateral femoral neck fracture login to view 4 more bullets bilateral femur fractures login to view 2 more bullets ipsilateral tibial shaft fractures ipsilateral acetabular fracture thoracic pulmonary injury login to view 3 more bullets cerebral hemorrhage, subdural hemorrhage early surgical treatment can exacerbate neurologic injury login to view 1 more bullet Anatomy Osteology largest and strongest bone in the body femur has an anterior bow linea aspera rough crest of bone running down middle third of posterior femur attachment site for various muscles and fascia acts as a compressive strut to accommodate anterior bow to femur Muscles 3 compartments of the thigh anterior login to view 2 more bullets posterior login to view 3 more bullets adductor login to view 4 more bullets Biomechanics musculature acts as a deforming force after fracture proximal fragment login to view 4 more bullets distal segment login to view 4 more bullets Classification Winquist and Hansen Classification Type 0 No comminution Type I Insignificant amount of comminution Type II Greater than 50% cortical contact Type III Less than 50% cortical contact Type IV Segmental fracture with no contact between proximal and distal fragment AO/OTA Classification 32A - Simple A1 - Spiral A2 - Oblique, angle > 30 degrees A3 - Transverse, angle < 30 degrees 32B - Wedge B1 - Spiral wedge B2 - Bending wedge B3 - Fragmented wedge 32C - Complex C1 - Spiral C2 - Segmental C3 - Irregula Presentation Initial evaluation Advanced Trauma Life Support (ATLS) should be initiated adequate resuscitation login to view 12 more bullets compensated shock login to view 7 more bullets Symptoms pain in thigh Physical exam inspection tense, swollen thigh login to view 3 more bullets affected leg often shortened tenderness about thigh motion examination for ipsilateral femoral neck fracture often difficult secondary to pain from fracture neurovascular must record and document distal neurovascular status Imaging Radiographs recommended views AP and lateral views of entire femur AP and lateral views of ipsilateral hip login to view 1 more bullet AP and lateral views of ipsilateral knee CT indications may be considered in midshaft femur fractures to rule-out associated femoral neck fracture Ipsilateral femoral neck rule-out protocol dedicated 10° internal rotation AP hip radiographs placed femoral neck in profile fine-cut CT of the hip 2 mm cuts CT Capsular Sign login to view 1 more bullet intraoperative fluoroscopic exam of the ipsilateral hip dedicated post-operative radiographs of the affected while patient is still in operating room Labs Septic nonunion ESR CRP most sensitive to the presence of a occult infection CBC WBC Adequate resuscitation IL-6 less than 500 pg/dL serum lactate less than 2.5 mmol/L base deficit within -2 or +2 Treatment Nonoperative long leg cast or hip spica cast indications login to view 2 more bullets Operative antegrade intramedullary nail indications login to view 1 more bullet outcomes login to view 8 more bullets retrograde intramedullary nail indications login to view 12 more bullets contraindications login to view 3 more bullets outcomes login to view 2 more bullets external fixation with conversion to intramedullary nail within 2-3 weeks indications login to view 3 more bullets outcomes login to view 3 more bullets open reduction internal fixation with plate indications login to view 3 more bullets outcomes login to view 4 more bullets Techniques Long leg cast or hip spica cast hip spica casting typically used in pediatric patients <5 years of age with length stable fractures long leg casting can be used in adult patients who are not surgical candidates need frequent follow-up for skin checks Antegrade intramedullary nail approach 3 cm incision proximal to the greater trochanter in line with the femoral canal technique positioning login to view 8 more bullets starting points login to view 21 more bullets entry reamer with soft tissue protector or awl pass ball-tip guidwire to desired depth/length of nail reaming login to view 8 more bullets femoral rod insertion login to view 4 more bullets interlocking screws login to view 9 more bullets reamed nailing has been associated with higher union rates compared to unreamed nailing reaming disrupts endosteal blood supply, but stimulates soft tissue and periosteal blood supply to fracture login to view 1 more bullet reaming extrudes medullary contents into fracture site login to view 1 more bullet increased micro emboli to lungs with reaming login to view 1 more bullet mild increases in marrow pressure with reaming login to view 3 more bullets reaming allows a larger diameter nail to be placed login to view 1 more bullet increases the area of isthmic contact with nail no increase in infection rates after reaming open fractures postoperative care weight-bearing as tolerated range of motion of knee and hip is encouraged pros 98-99% union rate low complication rate login to view 1 more bullet cons not indicated for use with ipsilateral femoral neck fracture increased rate of HO in hip abductors with antegrade nailing increased rate of hip pain compared with retrograde nailing mismatch of the radius of curvature of the femoral shaft and intramedullary nails can lead to anterior perforation of the distal femur Retrograde intramedullary nail approach 2 cm incision starting at distal pole of patella medial parapatellar versus transtendinous approaches nail inserted with knee flexed to 30-50 degrees technique positioned supine on radiolucent table login to view 3 more bullets entry point login to view 8 more bullets entry reamer with soft tissue protecting sleeve pass ball-tip guidewire login to view 1 more bullet ream femoral canal login to view 8 more bullets insert femoral nail login to view 1 more bullet place interlocking screws login to view 4 more bullets postoperative care weight-bearing as tolerated range of motion of knee and hip is encouraged pros technically easier allows for addressing other injuries surgically without changing patient position allows for direct comparison of rotation and leg length to nonoperative extemity union rates comparable to those of antegrade nailing no increased rate of septic knee with retrograde nailing of open femur fractures cons knee pain increased rate of interlocking screw irritation cartilage injury cruciate ligament injury with improper starting point External fixation with conversion to intramedullary nail within 2-3 weeks technique safest pin location sites are anterolateral and direct lateral regions of the femur 2 pins should be used on each side of the fracture line pros prevents further pulmonary insult without exposing patient to risk of major surgery may be converted to IM fixation within 2-3 weeks as a single stage procedure cons pin tract infection knee stiffness login to view 1 more bullet Open reduction and internal fixation with plate technique submuscular plating login to view 2 more bullets direct lateral approach login to view 8 more bullets Special considerations ipsilateral femoral neck fracture priority goes to fixing femoral neck because anatomic reduction is necessary to avoid complications of AVN and nonunion technique login to view 10 more bullets Complications Heterotopic ossification incidence 25% treatment rarely clinically significant Pudendal nerve injury incidence 10% when using fracture table with traction Femoral artery or nerve injury incidence rare femoral artery is medial to femur if proximal locking screw is placed proximal to lesser trochanter in retrograde nails cause can occur when inserting proximal interlocking screws during a retrograde nail Malunion and rotational malalignment most accurately determined by the Jeanmart method angle between a line drawn tangential to the femoral condyles and a line drawn through the axis of the femoral neck login to view 4 more bullets malrotation up to 15 degrees is usually well tolerated incidence proximal fractures 30% distal fractures 10% risk factors use of a fracture table increases risk of internal rotation deformities when compared to manual traction fracture comminution night-time surgery treatment if noticed intraoperatively, remove distal interlocking screws and manually correct rotation if noticed after union, osteotomy is required Delayed union treatment dynamization of nail with or without bone grafting Nonunion incomplete healing within 9 months of injury or no evidence of healing on successive radiographs over 3 months incidence <10% risk factors postoperative use of nonsteroidal anti-inflammatory drugs smoking is known to decrease bone healing in reamed antegrade exchange nailing for atrophic non-unions broken distal interlock screws can be seen on radiographs race between healing and implant failure is lost distal interlock screws are exposed to the greatest stresses undergo 4-point bending stress login to view 1 more bullet treatment reamed exchange nailing login to view 1 more bullet plate augmentation with nail retention login to view 2 more bullets compression plating login to view 3 more bullets Infection incidence < 1% treatment removal of nail and reaming of canal external fixation used if fracture not healed Weakness quadriceps and hip abductors are expected to be weaker than contralateral side Iatrogenic fracture etiologies risk factors antegrade starting point 6mm or more anterior to the intramedullary axis login to view 3 more bullets failure to overream canal by at least .5 mm Mechanical axis deviation (MAD) lengthening along the anatomical axis of the femur leads to lateral MAD shortening along the anatomical axis of the femur leads to medial MAD Anterior cortical penetration due to mismatch of the radius of curvature of the nail to the radius of curvature of the femur average radius of curvature of human femur is 120 +/- 36 cm starting points that are too posterior (especially piriformis start points) with relatively straight nails Compartment syndrome literature suggests this is significantly more common in ballistic injuries compared to blunt injuries