• Limb-length symmetry

• Knee range of motion

• Presence/absence of rotational abnormality

• Hip examination for possible slipped capital femoral epiphysis (SCFE)

• An orthoroentgenogram is obtained to assess alignment, ± femoral deformity, and limb length discrepancy. Figure 1 shows a typical preoperative orthoroentgenogram, obtained with the patient facing anterior, delineating coronal tibial and/or femoral deformity and limb length discrepancy.

• Anteroposterior (AP) and frog-leg lateral radiographs are obtained to assess the hips. In Figure 2, the AP (Fig. 2A) and frog-leg lateral (Fig. 2B) radiographs demonstrate a right SCFE.

• An AP/lateral radiograph is obtained of the entire tibia, including the ankle joint. Figure 3 shows an orthoroentgenogram and lateral radiograph of the tibia in a 6-year-old.

• Computed tomography (CT) or magnetic resonance imaging (MRI) can be done if the patient is young or in a patient with long-standing problems to assess the joint surface. Figure 4 shows an MRI of the right proximal tibia delineating both the joint contour and the proximal physis.

• CT or MRI is also used for possible growth plate assessment.