Flynn_Ch030.indd

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Operative Techniques in Pediatric Orthopaedic Surgery

Positioning

■ The patient is positioned supine on the operating table ( FIG 3 ). ■ The fluoroscopy machine can be brought in from the op- posite side of the table so that it is out of the surgeon’s way. ■ A small bump placed under the ipsilateral hip is helpful to counter external rotation of the femur so that the patella is pointed directly up. ■ The approach for treatment of tibial fractures depends on the technique used. ■ Elastic nails and external fixation pins are placed through stab incisions. ■ Open reduction and internal fixation approaches are the same as described for adult injuries elsewhere in this text.

Elastic intramedullary nails External fixator plate

Cannulated screws K-wires External fixator Extraphyseal plate

Approach

FIG 2 ● Suggested fixation techniques for the pediatric tibia.

■ It is used at our institution primarily for distal-third fractures. ■ After successful use in the treatment of pediatric femur frac- tures, the elastic intramedullary nail technique has also been successfully applied to the tibia. 3,6,14 Preoperative Planning ■ Full-length radiographs of the tibia and fibula should be obtained. ■ Views of the contralateral side can be helpful to determine proper length in comminuted fractures. ■ A clinical examination of the well side can guide the sur- geon in determining rotational alignment. ■ The choice of fixation is determined by fracture location, comminution, and soft tissue envelope ( FIG 2 ).

FIG 3 ● Positioning for operative treatment of tibia fractures. The hip is elevated on a towel roll so that the patella points directly anteriorly. The fluoroscopic unit is brought in from the opposite side of the table to avoid interference with the surgeon.

T E C H N I Q U E S

■ External Fixation ■ In the supine position, traction is used to roughly align the fracture. ■ Pins are placed using fluoroscopic guidance to avoid the physis. ■ Particular care is required when placing the most proximal pin. ■ The tibial tubercle physis is not easily seen on the AP radiograph. ■ A lateral view is required to avoid injury to this structure and a late procurvatum deformity. ■ An array of pin sizes should be available. ■ Full-sized adolescents may require 5-mm pins as in adults, but smaller children require smaller pins to avoid an overly stiff construct. ■ Four-millimeter pins should be used for younger children (ie, younger than 10 years old), and I have found an adult wrist external fixator with 2.5-mm pins useful for treatment of toddlers with open injuries requiring fixation such as lawnmower injuries. ■ Multiple pins are placed on each side of the fracture, one close (within several centimeters of the fracture line) and one far (at least 2 to 3 cm away from the physis).

■ Children’s bone is often quite hard. Despite using “self-drilling” pins, I prefer to predrill the anterior cortex before placing the pin. ■ Ring sequestra may develop from the heat generated in hard bone if pins are drilled directly in some children. ■ The roughly triangular shape of the tibia should be noted (see FIG 1A ). ■ The pins should be started on the tip of the anterior tibia or just medial and aimed slightly medially. ■ Laterally aimed pins may be unicortical, as the lateral cor- tex of the tibia is vertically oriented. ■ The fracture is then manually reduced, using the pins for traction if necessary, and the frame is connected ( TECH FIG 1A ). ■ In cases of soft tissue injury requiring the ankle to be immobi- lized, extending the frame to the first or fifth metatarsal can allow easier wound management ( TECH FIG 1B ). ■ The pin sites are covered with iodine-soaked gauze. ■ I have caregivers begin cleaning the pin sites with half- strength hydrogen peroxide once or twice daily after the 1-week follow-up visit. ■ A posterior splint is applied to immobilize the ankle and allow soft tissue healing. It is removed after 2 to 3 weeks to begin ankle range of motion.