The femur, also known as the thigh bone, is one of the largest and strongest bones in the body extending from the hip joint all the way down to the knee joint. Because it is so strong, it requires a significant force to break it.
With that being said, certain medical conditions can weaken the bone and make it more vulnerable to fracture. These include osteoporosis, tumors, infection, and even certain bisphosphonate medications used to treat osteoporosis. Breaks of these sorts are referred to as pathologic femur fractures. Pathological fracture of the femur is a debilitating complication in patients with advanced stage of malignancy.
Femur fractures are generally separated into three broad categories:
Proximal Femur Fractures
Proximal femur fractures, or hip fractures, involve the uppermost portion of the thigh bone just adjacent to the hip joint. These fractures are further subdivided into:2
Femoral neck fractures are those that occur when the ball of the ball-and-socket joint is broken at the top of the femur.
Intertrochanteric hip fractures occur just below the femoral neck and are more easily repaired than femoral neck fractures.
Femoral Shaft Fractures
A femoral shaft fracture is a severe injury that usually occurs as a result of a high-speed car collision or a fall from a great height.
The treatment almost always requires surgery. The most common procedure involves the insertion of a metal pole (known as an intramedullary rod) into the center of the thigh bone.3 This helps reconnect the two ends which are then secured with screws above and below the fracture. The intramedullary rod almost always remains in the bone but can be removed if needed.
A less common technique involves the use of plates and screws to secure the fracture which is then held in place by an external fixator. The fixator, which is situated outside of the leg but penetrates the skin to stabilize the bone segments, ensures that the femur is fully immobilized and better able to heal. External fixation is usually a temporary treatment for patients who have multiple injuries and cannot have a longer surgery to fix the fracture.3
External Fixation for Fractures
Supracondylar Femur Fractures
A supracondylar femur fracture, also called a distal femur, is a break in the bone that occurs just above the knee joint.4 These fractures often involve the cartilage surface of the knee joint and are most commonly seen in people with severe osteoporosis or those who have previously undergone total knee replacement surgery.
A supracondylar femur fracture is a problematic condition as it can increase the risk of developing knee arthritis later in life.4
The treatment of a supracondylar femur fracture is highly variable and may involve a cast or brace, an external fixator, an intramedullary rod, or the use of plates and screws.
A femur fracture is always considered a medical emergency requiring immediate evaluation and treatment in a hospital. The treatment is largely dependent on the location of the fracture and the pattern and extent of the break.