What is a key X-ray finding for a slipped capital femoral epiphysis (SCFE)?

In the context of slipped capital femoral epiphysis (SCFE), a significant radiographic finding is Klein's line not intersecting with the epiphysis. Klein's line is drawn along the superior border of the femoral neck, and in a normal hip, this line should intersect with the epiphysis of the femoral head. However, in cases of SCFE, where there is a slippage of the femoral head relative to the neck, this line no longer intersects with the epiphysis, indicating an abnormal relationship between the femoral head and neck.

This finding helps to confirm the diagnosis of SCFE as it highlights the displacement of the capital femoral epiphysis. A failure of Klein's line to intersect signifies that the femoral head has moved posteriorly and inferiorly relative to its normal anatomical position, which is characteristic of SCFE. Recognizing this key X-ray finding is crucial for accurate diagnosis and timely management of the condition, which is particularly important in pediatric patients to prevent further complications such as avascular necrosis.

The other choices do not characterize SCFE effectively. Increased joint space may occur due to various conditions but is not specifically indicative of SCFE. A fracture line in the femur is not a