The femur, or thigh bone, is the longest, heaviest, and strongest bone in the human body. Fractures usually result from a high-energy impact, such as a motor vehicle accident or a significant fall. Because of the tremendous force involved and the resulting instability, a broken femur in an adult almost always requires surgical intervention for proper healing and recovery. Non-operative treatment is typically reserved only for specific, rare exceptions or for patients too medically fragile to undergo an operation.
Why Immediate Stabilization is Necessary
The powerful muscles surrounding the thigh, including the quadriceps and hamstrings, naturally pull the fractured bone fragments out of alignment when the femur breaks. This displacement causes shortening, angulation, and rotational instability, which cannot be adequately overcome by an external cast or splint. Unstable fractures must be stabilized surgically to restore the bone’s proper length, alignment, and rotation.
Failure to achieve stable fixation can lead to severe complications, such as malunion (healing in an incorrect position) or nonunion (failure to heal altogether). Early surgical stabilization is also associated with a reduction in systemic complications and mortality, especially in patients with multiple injuries, by allowing for earlier mobilization. Furthermore, immediate stabilization prevents sharp bone fragments from damaging nearby blood vessels and nerves.
Standard Surgical Procedures
The most common method for treating fractures of the femoral shaft is Intramedullary (IM) Nailing. This technique involves inserting a long, specialized metal rod into the marrow cavity that runs down the center of the femur, passing across the fracture site. Screws are then used at the top and bottom of the rod to lock it into the bone, which prevents shortening and rotation during the healing process.
IM nailing is favored because it shares the weight-bearing load with the bone and minimizes disruption to the surrounding soft tissues, which accelerates healing and allows for earlier weight-bearing. For fractures occurring near the ends of the bone, such as the distal femur near the knee or the proximal femur near the hip joint, plates and screws are often used instead. This hardware is fixed to the outer surface of the bone to hold the fragments in place, which is useful for complex fractures that extend into the joint.
Non-Surgical Treatment Exceptions
Although surgery is the standard, non-surgical management is an option in rare and specific situations, primarily for select pediatric fractures. Children possess a remarkable ability for bone remodeling, meaning some fractures can heal without perfect alignment, especially if the fracture is stable and non-displaced. Treatment may involve prolonged immobilization using a spica cast or skeletal traction, where weights and pulleys are used to align the bone.
For adults, non-operative management is generally limited to two scenarios: a patient who is non-ambulatory with significant medical comorbidities that make surgery too risky, or a rare, completely stable and non-displaced hairline fracture. Even in these exceptional cases, the patient must be monitored closely with frequent X-rays, as there is a risk of the fracture displacing during the healing period, which would then necessitate emergency surgery. Non-operative management of hip fractures, which occur at the top of the femur, is associated with high rates of complications and mortality, reinforcing that surgery is the accepted treatment.
Recovery and Rehabilitation Timeline
Recovery following a broken femur is lengthy and depends heavily on the severity of the fracture and the patient’s overall health. Initial bone healing, where a hard callus begins to form, typically takes about three to six months for a successful union. Immediately after surgery, patients begin a period of non-weight bearing or partial weight bearing, with the surgeon determining the progression based on the stability of the fixation and radiographic evidence of healing.
Physical therapy (PT) begins early to manage pain, restore range of motion in the hip and knee, and prevent muscle atrophy. The first six weeks often focus on gentle range-of-motion exercises before progressing to muscle strengthening and balance training. Most patients can return to everyday activities around four to six months after the surgery, but a full functional recovery commonly takes six months to a year. In some instances, the hardware used for fixation may be removed in a subsequent surgery once the bone has completely healed.