Summary Distal femur fractures are traumatic injuries involving the region extending from the distal metaphyseal-diaphyseal junction to the articular surface of the femoral condyles. Diagnosis is made radiographically with CT studies often required to assess for intra-articular extension. Treatment is generally operative with ORIF, intramedullary nail, or distal femur replacement depending on available bone stock, age of patient, and patient activity demands. Epidemiology Incidence common login to view 2 more bullets Demographics bimodal distribution login to view 2 more bullets Pathophysiology Mechanism young patients login to view 1 more bullet older patients login to view 1 more bullet Anatomy Osteology anatomical axis of the distal femur is 6-11 degrees of valgus login to view 1 more bullet distal femur becomes trapezoidal in cross-section towards the knee login to view 1 more bullet posterior halves of both condyles are posterior to the posterior cortex of femoral shaft Muscles key deforming forces login to view 4 more bullets Ligaments anterior cruciate ligament (ACL) posterior cruciate ligament (PCL) medial collateral ligament (MCL) lateral collateral ligament (LCL) Biomechanics hamstring and quadriceps login to view 1 more bullet adductor magnus login to view 2 more bullets gastrocnemius login to view 2 more bullets Classification Descriptive supracondylar intercondylar OTA: 33 A: extraarticular B: partial articular login to view 2 more bullets C: complete articular login to view 1 more bullet Presentation History patients commonly present after fall or traumatic event Symptoms common symptoms login to view 2 more bullets Physical exam inspection login to view 5 more bullets neurovascular exam login to view 6 more bullets Imaging Radiographs recommended views login to view 2 more bullets additional views login to view 6 more bullets findings login to view 11 more bullets CT scan indications login to view 3 more bullets findings login to view 3 more bullets Angiography indications login to view 3 more bullets findings login to view 3 more bullets Treatment Nonoperative immobilization with hinged knee brace login to view 6 more bullets Operative closed reduction and external fixation (ExFix) login to view 11 more bullets open reduction internal fixation (ORIF) login to view 13 more bullets closed reduction and intramedullary fixation (IMN) login to view 11 more bullets arthroplasty login to view 17 more bullets Techniques Hinged knee brace technique login to view 4 more bullets complications login to view 2 more bullets External Fixation technique login to view 2 more bullets complications login to view 1 more bullet Open Reduction Internal Fixation (ORIF) approach login to view 25 more bullets technique login to view 30 more bullets complications login to view 2 more bullets Retrograde intramedullary nail approach login to view 11 more bullets technique login to view 7 more bullets complications login to view 3 more bullets Arthroplasty and distal femoral replacement approach login to view 2 more bullets technique login to view 1 more bullet complications login to view 5 more bullets Complications Knee pain/stiffness treatment login to view 2 more bullets Symptomatic hardware risk factors login to view 5 more bullets treatment login to view 1 more bullet Malunions risk factors login to view 5 more bullets treatment login to view 2 more bullets Nonunions incidence login to view 1 more bullet risk factors login to view 1 more bullet treatment login to view 2 more bullets Infection risk factors login to view 1 more bullet treatment login to view 3 more bullets Implant failure incidence login to view 1 more bullet risk factors login to view 3 more bullets Loss of fixation varus collapse (most common) login to view 2 more bullets Proximal (diaphyseal) screw failure login to view 1 more bullet