Component position:
1. Acetabular inclination: Angle between horizonatl base line and actabular orifice is usually 40-50 degrees. More angle = verticle inclination, less angle = horizaontal inclination
2. Acetabular anteversion: on true lateral view, angle between axis of acetabulum and a line perpendicular to the base line
2. Verticle position of the femur: Perpendicluar distance between centre of hip and interteardrop line
3. Mediolateral position of the femur: Distance between centre of hip and interteardrop line
4. Femoral stem: should be within the centre of medullar canal or slightly medially.
5. Length: Distance between proximal edge of lesser trochonter and base of ischial tuberosity
Component fixation:
Lucent lines between cement and bone usually stabilise in 2 years, measuring 0.1 to 1.5 mm. More 2 mm indicates loosening.
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
