- See:
        - Garden I & II
        - Garden III & IV

- Discussion:
    - refers to the angle of the compression trabeculae on AP view relative to the longintudinal axis of the femoral shaft and the angle of
             compression trabeculae on the lateral view relative to the femoral shaft;
             - on the AP this angle should be 160 deg vs 180 deg on the lateral;
    - acceptable reduction lies w/in range of 155-180 deg on both views;
             - acceptable reduction minimizes non-union and AVN;
             - when alignement index was < 155 deg or > 180 deg incidence of AVN rose from 7.3% to 53.8%;
             - valgus reduction > 20 deg results in increased rate of AVN;

- Lowell's Alignment Theory:
    - radiographic outline of femoral head & neck junction will have convex outline of femoral head meeting concave outline of femoral
             neck regardless on all radiographic views;
             - this outline produces image of S or reversed S curve;
             - hence, if outline reveals an unbroken C curve frx is not reduced