Figure 5

Definitions of the allowable and functional ROM of the new THR after simulated implantation. The allowable ROM was determined as the maximum angles of (a) flexion, (b) extension, (c) adduction, (d) abduction, and (e) internal and (f) external rotation of the femoral component within the acetabular component relative to the pelvic ACS without constraints or limitations from the bony structures. The functional ROM was those angles allowed by constraints from both the implants and the bony structures.