A lateral knee radiograph is taken with the patient lying or seated on the affected side, knee flexed about 20–30° so femoral condyles are superimposed and the patella is in profile. The X‑ray beam is directed horizontally, perpendicular to the joint space, and centered at the joint to include distal femur, proximal tibia and patella. Immobilize and position to avoid rotation.

Knee X‑rays are typically taken in three views: anteroposterior (AP), lateral and a skyline/sunrise view of the patella. Three views better assess joint space, fractures, alignment and the patella. In some situations—minor injury or basic screening—two views (AP and lateral) may be used, but three views are generally recommended for a full evaluation.

A Rosenberg view is a weight-bearing, posterior–anterior knee X‑ray taken with the patient standing and the knee flexed about 45°. This PA flexion view accentuates joint-space narrowing and osteoarthritic changes between femoral condyles and the tibial plateau, often revealing cartilage loss and joint degeneration not seen on routine AP or nonweight-bearing films. It’s commonly used to evaluate knee osteoarthritis.

A lateral view of the knee joint space is a side-on radiographic projection that images the patellofemoral and tibiofemoral compartments. It shows soft-tissue swelling or effusion, alignment of femoral and tibial condyles, joint-space height, cartilage loss, and occult fractures. Clinically it helps assess osteoarthritis, trauma, dislocation, and joint effusion, complementing AP and skyline views for comprehensive knee evaluation.

Position the patient so the body part is rotated 90° from the frontal plane and lies parallel to the image receptor. Place the side of interest adjacent to the detector (left lateral for chest when possible). Center the central ray perpendicular to the receptor over the area of interest, collimate tightly, use appropriate exposure settings, immobilize, instruct breath‑hold for chest/spine, apply shielding, and mark the side before exposure.

The skyline (sunrise) projection is an axial, tangential knee X‑ray taken with the knee flexed so the beam skims the patella. It visualizes the patellofemoral joint and patellar articular surface, helping detect fractures, subluxation or dislocation, chondral defects and joint space narrowing. Different beam angles and flexion degrees (eg 30–45°) optimize visualization of the trochlear groove.