The femur, or thigh bone, is the longest and strongest bone in the human body, extending from the hip to the knee. This bone is built to withstand significant forces, supporting the entire upper body weight during standing and movement. Because of its immense strength, a fracture typically results from high-energy trauma, such as a motor vehicle accident or a fall from a substantial height. The femur’s role as a major weight-bearing structure makes any break a serious orthopedic event that demands immediate medical attention.
Mobility After a Femur Fracture
Attempting to walk on a fractured femur is generally impossible and extremely dangerous due to the bone’s primary function in supporting body weight. A complete break compromises the structural integrity of the entire leg, leading to immediate instability and the inability to bear any load. The severe pain experienced upon injury prevents any weight application.
Applying weight to a broken femur risks displacing the bone fragments further, which can cause significant secondary damage. Sharp bone edges can sever major blood vessels and nerves running through the thigh, creating complications like severe blood loss or nerve damage. For this reason, immediate post-injury management involves strict non-weight-bearing status. The only exception is with non-displaced stress fractures, which are hairline cracks from overuse and may permit limited, protected weight-bearing under a doctor’s guidance.
Common Types of Femur Fractures
Femur fractures are classified based on their location along the bone and the nature of the break. The location significantly impacts treatment and potential complications.
Location-Based Classification
Proximal femur fractures occur near the hip joint, often called hip fractures, and include breaks in the femoral neck or between the trochanters. Femoral neck fractures are concerning because they can disrupt the blood supply to the head of the femur, potentially leading to bone death. Femoral shaft fractures involve the long, middle section of the bone, and these breaks are nearly always the result of high-energy trauma. Distal femur fractures happen in the area just above the knee joint, sometimes extending into the joint cartilage.
Fracture Pattern Classification
Fractures are also categorized by their pattern. These include transverse (straight across), spiral (caused by a twisting force), or comminuted, where the bone shatters into three or more pieces. An open or compound fracture is the most severe type, where bone fragments pierce the skin, increasing the risk of infection and soft tissue damage.
Immediate Steps Following Injury
A suspected femur fracture requires an immediate call to emergency services for professional medical transport. The injured person should be kept as still as possible to prevent further displacement of the bone fragments and minimize soft tissue injury. If the limb appears severely deformed, emergency medical personnel may apply gentle, inline longitudinal traction to temporarily realign and stabilize the extremity for transport.
The priority before hospital arrival is to manage the patient for shock, control any external bleeding, and prevent movement of the broken bone. Upon reaching the hospital, diagnostic imaging, typically X-rays and sometimes a CT scan, confirms the fracture location, pattern, and severity. This precise information is used by the orthopedic surgeon to plan the definitive repair.
Medical Intervention and Rehabilitation
Definitive treatment for most traumatic femur fractures involves surgical stabilization, usually performed within 24 to 48 hours of the injury. The most common procedure is open reduction and internal fixation (ORIF), where the bone fragments are realigned and secured with hardware. For shaft fractures, an intramedullary nail is often inserted down the center of the bone, while plates and screws are typically used for fractures near the hip or knee joint.
Following surgery, the recovery process is prolonged, beginning with a period of strict non-weight-bearing. Initial bone healing can take between six to twelve weeks, during which the patient uses crutches or a walker without putting weight on the injured leg. Physical therapy (PT) begins early, focusing on gentle range-of-motion exercises for the hip and knee to prevent stiffness.
The gradual progression to full weight-bearing is a multi-month process. It starts with partial weight-bearing only when the surgeon confirms sufficient bone healing, usually around six weeks to three months post-surgery. PT then shifts to intensive muscle strengthening, balance training, and gait re-education to restore function. Full bone healing often takes three to six months, but the return to pre-injury activity levels can take anywhere from six to twelve months.