Femur fractures (Orthopaedic Trauma Association classes 31, 32, 33)1 are common childhood injuries, occurring at a rate of 19 per 100,000 children in the United States.2 Peak occurrence is bimodal at ages 2 and 17 years. The most common mechanism of injury in children under 6 years is a fall, and hip spica casting is the preferred treatment modality in this group.3-5
A bar connecting the legs of the spica cast has been shown to facilitate patient transport5 and significantly decrease mechanical failure of the spica cast.6 This bar often consists of a broom handle or pipe that must be cut to size during the case and subsequently incorporated into the cast—tasks that are often inconvenient and time-consuming for on-call or emergency department staff unfamiliar with orthopedic tools.
In this article, we review a spica cast application that incorporates a low-cost, lightweight technique for fabricating a connecting bar from existing fiberglass casting material. The Institutional Review Board at Connecticut Children’s Medical Center approved this work.
Technique of Double-Leg Spica Casting With Fiberglass Bar
A spica casting table (Orthopedic Systems) with a well-padded post is placed on the operating room table and adjusted to the length of the patient from perineum to just below the shoulders. With the patient under general anesthesia, folded towels are used to provide 2 to 4 cm of padding on the anterior torso, atop which a waterproof pantaloon is applied. The patient is transferred to the spica table, and the patient’s arms are gently secured to the casting table with cast padding or tape in an abducted position at the shoulders. A surgeon controls the legs by holding the feet with the long fingers just above the heels, the index fingers on the anterior ankle, and the thumbs on the soles of the feet. Cast padding is wrapped from the nipple line to the supramalleolar region on each leg. The bony prominences of the malleoli, patella, fibular head, femoral condyles, iliac crests, and coccyx are well padded.
Fiberglass is then rolled without compression onto the patient, beginning with the torso and perineal areas. The injured leg is wrapped to its final length above the malleoli while the uninjured leg is kept free. Maintaining the position of the injured leg with simultaneous molding at the fracture site, typically to promote valgus, allows fracture reduction. The fracture position is then checked under image intensification. For femur fractures, hip abduction and flexion are set to 45° and 90°, respectively, while knee flexion is between 50° and 90°. The uninjured leg is then wrapped with fiberglass. Additional strips of fiberglass can be used to reinforce weak junctional regions between the torso and the legs, posteriorly over the “intern’s triangle” and anteriorly along the hip crease.
A connecting fiberglass bar is then created using a fiberglass roll once the cast is hardened. A 2-inch fiberglass roll is wrapped around one leg to secure its position (Figure 1A) and then rolled around the second limb (Figure 1B). Fiberglass is then pulled taut and rolled around the bridge that has been created in order to thicken the bar (Figure 2). The roll is again brought around the closest limb, wrapped back across the bridge to the other limb, and rolled out to its full length. Last, the legs are abducted 1 to 2 cm to tension the bar (Figure 3). Although this does not produce enough movement to cause a crease and a resultant ulcer, careful inspection of common pressure points (eg, popliteal fossa) should be performed after the cast is complete.
The chest towels are removed, and the final cast is inspected clinically and fluoroscopically at the fracture site before extubation. The cast is trimmed as needed to ensure room for perineal care, as well as full ankle flexion and extension without impingement. Cast edges are further petaled with plastic tape (Hy-Tape International) to provide padding and prevent the waterproof lining from tearing.
Postoperative care involves overnight observation and caregiver practice in perineal care. Frequent rotation from supine to prone is encouraged. Nurses confirm car-seat fit before discharge. If needed, radiographs are obtained 7 to 10 days later to help with wedging adjustment. The cast is removed in the clinic when adequate callus is appreciated on subsequent radiographs.
Case Series
Our experience with this technique in 16 unilateral femur fractures has been favorable (Table). Patient age ranged from 5 months to 3 years. Mean pretreatment angulation was 13° varus and 11° procurvatum. The majority of fractures were femoral shaft fractures; 1 was proximal, 2 distal.