Slipped Capital Femoral Epiphysis Hip Pinning

CHAPTER 46
Slipped Capital Femoral Epiphysis Hip Pinning

Kirk Aadalen and John F. Sarwark

Definitions

New terminology

Unstable slip: defined as clinical and radiographic evidence of slipped capital femoral epiphysis (SCFE) and inability to bear weight, even with assistive devices secondary to pain.

Stable slip: defined as clinical and radiographic evidence of SCFE and the ability to bear weight.

Indications

1. Mild, moderate, and some severe unstable (acute or acute-on-chronic) slipped capital femoral epiphysis (SCFE) (Figs. 46–1A and 1B)

2. Mild or moderate stable (chronic) SCFE

Contraindications

1. Severe acute on chronic SCFE

2. Severe chronic SCFE

Preoperative Preparation

1. Obtain hip radiographs including anteroposterior (AP) and true or cross table lateral views of the affected hip.

2. Appropriate medical and anesthesiology evaluation

3. Strict bed rest

4. Skin traction to affected limb for comfort

Special Instruments, Position, and Anesthesia

1. C-arm image intensifier fluoroscopy is required for percutaneous pinning.

2. A power driver with Kirshner wires and a 7.3-mm cannulated screw set is required.

3. The patient is placed supine on a radiolucent table or fracture table with the affected leg abducted 10–15 degrees and internally rotated moderately and without force (. 46–2).

4. Carefully pad all pressure points.

5. Place image intensifier between the patient’s legs in order to obtain AP and lateral hip images by simply rotating around the arc of the C-arm machine.

6. General anesthesia is used during the procedure.

1. Position the leg with 10–15 degrees of abduction and moderate internal rotation. This places the femoral neck as close as possible to a position parallel to the floor in order to obtain true AP and lateral views.

2. The starting point for the screw should be on the anterior surface of the femoral neck, not the lateral cortex of the proximal femur as in adult femoral neck fixation.

3. Commonly, as the proximal capital femoral epiphysis “slips” it rotates posteriorly. The more severe the slip, the more anterior the entry position of the guide pin on the femoral neck will need to be in order to achieve optimal, final, safe screw position (Fig. 46–1B).

4. The only safe location for screw placement is center-center with respect to the femoral head on the AP and lateral images. At least 5 mm of a margin from the femoral head surface should be seen.

5. A single larger 7.3-mm cannulated screw is technically easier and has better results than multiple screws.