Knee X-ray Radiology

Knee Xray Radiology

Normal bone anatomy of right knee

Anterior view of right knee

Medial view of right knee

Posterior view of right knee

Mechanical axis

Mechanical axis of lower limb

X-ray Knee

Anteroposterior view: Supine position with fully extended knee and central X-ray beam directed vertically at a 5-7° cephalad angulation.

Notch (tunnel) view: Prone position with 40° knee flexion and the Xray beam is directed caudally toward the knee at a 40° angle from the vertical.

Weight-bearing AP view is preferable.

Standing flexion views at 30°-40° allows assessment of articular wear in deeper flexion that is may not be apparent on standard AP views in early degenerative knee arthritis.

Anterior view of right knee

AP Xray view of right knee

Xray Right Knee

Anterior view of right knee

AP Xray view of right knee

Standing flexion views

Standing weight-bearing flexion

Medial joint space narrowing with lateral joint space preservation.

Weight-bearing views

Standing AP

Medial joint space narrowing with preservation of lateral compartment.

Standing Lateral

Assess tibia wear pattern and determine tibia slope

Stress radiologic views

Valgus stress applied. Lateral joint space preservation.
Intact MCL (medial collateral ligament).

Varus stress applied demonstrating medial joint space narrowing. Intact LCL (lateral collateral ligament).

Lateral view: Lateral position with 30° knee flexion. The Xray beam is directed medially at 5°-7° cephalad angulation.

Lateral view of the knee

Radiological Patellar views

Standing anterior-posterior (AP) and lateral views
Merchant view of patella
CT in select cases (assess TT-TG)

Patellar position

Sunrise view: Prone position with knee flexed to 115° the beam is directed at a 15° cephalad angulation toward patella.
Merchant view: Supine position with 45° knee flexion the beam is directed at a 60° caudal angle through patella.