Femur Immobilization – Indications, Contraindications

Femur Immobilization is primarily due to fractures and dislocations. Each of these injuries dictates a specific immobilization and stabilization technique. In the acute phase of the injury, the application of external devices may facilitate transportation and other treatment necessities of the polytrauma patient. The most common cause of the 2 injuries is trauma which may cause an open or closed fracture, but both can typically be immobilized with the same principles. Later in the course of the treatment, other stabilization options are available.

Anatomy and Physiology

The femur is the long bone of the thigh and the largest and strongest bone in the human anatomy. The proximal femur has large muscle attachments and a joint at the pelvis forming the hip. The distal femur also has large muscle-group attachments and forms the knee joint with the proximal tibia. The sites of fractures are often named in relation to the anatomy where the fracture occurs.

The femur has many common names and medical names which describe different portions of the bone. The femoral shaft is the diaphysis and is commonly fractured in trauma. The head of the femur is the proximal-most portion of the bone which directly joins to the pelvis forming the hip joint. The femoral neck is the region of bone joining the head to the femoral shaft. The greater and lesser trochanter are protuberances of bone on the proximal end of the femur, and each aid in defining the location of fractures. The distal femur has structures involved in the knee joint called condyles and epicondyles for muscle attachment.

Examining the anatomy of the injured limb should include all systems involved, including circulation, peripheral nerves, and motor function. Injuries often affect these non-boney structures due to the force causing the fracture or dislocation of the femur, also injuring surrounding anatomy. Absent or decreases in the circulation or sensation of the lower limb could direct care and should be carefully monitored before and after immobilization.[rx][rx]

Indications of Femur Immobilization

Early diagnosis may not be feasible with non-displaced fractures or when it is unclear if there is a fracture or dislocation or both.

• In the pre-hospital setting, immobilization should be considered with obvious deformities, pain, swelling, and shortened limb and patients unwilling to use actively move the proximal lower extremity.
• Patients who hold the limb in a fixed position, such as shortened with internal or external rotation, or have other signs of injury should also be considered for immobilization.
• Often patients with femur fractures will have a significant decrease in pain by manual traction and subsequent traction splint placement.
• In the hospital, dislocations should be reduced early, if possible. If the reduction is not successful or there are other life-threatening conditions that need treatment, immobilization is not necessary but is preferred to support the affected limb in a position of comfort until the patient can go to the operating room for definitive treatment.
• The location of the fracture or the need to treat other more urgent and life-threatening injuries may direct the initial immobilization in the emergency department.[rx]

Contraindications of Femur Immobilization

• Situations in which caution must be exercised include the presence of thermal or electrical burns, open fractures, grossly contaminated wounds, and significant soft tissue swelling.
• Injuries that violate the skin or open wounds. Antibiotic administration should be considered for these patients depending on the severity of the lesion.[rx] These patients also require additional soft tissue care, which may necessitate tissue debridement and skin closure before splint application.
• Injuries that result in sensory or neurologic deficits. The complications of splint placement such as compartment syndrome, pressure injuries, or malreduction may go unnoticed if the patient has a concurrent nerve injury. These patients should undergo evaluation by a surgeon before splint application as neurologic findings may be a sign of a surgical emergency.
• Injuries to the vasculature require special attention by vascular surgeons, as these may require urgent operative intervention. Furthermore, evaluation of the vasculature is essential both before and after splint application, as the reduction of some fractures may result in acute arterial injury or obstruction if trapped between the fracture fragments.
• Patients with peripheral vascular disease or neuropathy. Special care should be taken when applying lower extremity splints in these patients since their baseline sensation may be altered. These patients have difficulty detecting pressure sores, skin irritation, and possible vascular compromise.
• There are few contraindications, primarily if the patient refuses a splint or other immobilization. Some splints are better suited for specific fractures, but if a fracture is suspected or diagnosed, using standard splinting guidelines has no absolute contraindications.
• It may be difficult to place traction splints in the lower extremity multiple injuries, especially when ankle or other foot injuries make the straps impossible to attach or too uncomfortable. Certain situations like this may contraindicate some immobilization techniques, but with multiple options available, another option should be chosen.[rx]

Equipment of Femur Immobilization

At the most basic level, anything placed with adequate strength, size, and length may be considered as an immobilization option. These should immobilize the hip and the knee as well to prevent movement and further injury. In a non-medical environment, these basic principles should guide the placement of an improvised device.

There are multiple devices that may be used in immobilizing the femur. Pre-hospital providers often use commercial traction splints which have a rigid element with straps to attach to the patient and then apply traction using cords and tension devices. In the hospital, weighted traction splints may be placed on the patient. One of the 2 methods creates this traction. The non-invasive method is to use a strap on the ankle and keeping the injured lower extremity straight weight is hung from the end of the bed typically using a frame and pulley system. Some fractures in the multiply injured patient may require transfemoral or transtibial pins to be placed which then allow skeletal traction. These pins are placed with careful sterile preparation and need specialized equipment typically found in orthopedic operating trays.[rx][rx][rx]

Personnel

One person may place some splints, but traction splints require 2 or more people. One person should hold manual traction while the other person places the splint. Analgesia and sedation are needed to place transfemoral/transtibial skeletal traction pins, and this will require potentially other physicians, nursing support, and possibly respiratory therapy or other support staff where available.[rx]

Preparation

Assembling all the appropriate equipment is often all that is needed and extra staff to hold the extremity and place the splint.

Extra preparation is needed if placing invasive pins for traction immobilization. The skin should be carefully cleaned using sterile technique. A sterile field should be created if possible, and analgesia and sedation should be administered.[rx]

Document the neurovascular exam before any immobilization device is placed and any time the limb is manipulated, or the immobilization is changed to a different device.

Technique

Most traction splints involve an ankle harness and some sort of cord or rigging to create the tension. Prior to placement, a neurovascular exam should be assessed to determine the patient’s current baseline neurovascular status. Make a note of any abnormalities and make sure the placement of any splint does not further compromise to neurovascular status. Reevaluate the neurovascular states distal to the splint, or any device placed immediately after and with serial exams to ensure changes are promptly discovered and treated appropriately.

Each splint has specific directions for use but can often be deciphered by the need for securing the splint to the patient and the need for traction to be applied. There are 2 basic forms of this and many places the affected limb in the anatomic position, but there are some which use a flexed hip at 30 to 45 degrees and the knee flexed between 60 to 90 degrees.[rx]

Complications

Improper placement of a splint may cause complications due to the straps or parts of the rigid structure of the splint causing local injuries. Once immobilization has been achieved, continually test distal circulation, sensation, and motor. Perform frequent interval reevaluation of the neurovascular status as changes often occur in the acute phase of the injury as swelling increases. Complications most commonly occur in relation to one of these areas.

Swelling may also cause local and distal complications, and the patient should be frequently evaluated for compartment syndrome.

Transfemoral/transtibial pins may have a localized infection or bleeding. Routine pin site care should address these to prevent these potential complications.[rx][rx]