-
Hip, spine, and pelvis move in coordination with one another during activity, forming the lumbopelvic complex (LPC).
-
These movements are characterized by the spinopelvic parameters sacral slope, pelvic tilt, and pelvic incidence, which define a patient’s morphotype.
-
LPC kinematics may be classified by various systems, the most comprehensive of which is the Bordeaux Classification.
-
Hip–spine relationships in total hip arthroplasty (THA) may influence impingement, dislocation, and edge loading.
-
Historical ‘safe zones’ may not apply to patients with impaired spinopelvic mobility; adjustment of cup inclination and version and stem version may be necessary to achieve functional orientation and avert complications.
-
Stem design, bearing surface (including dual mobility), and head size are part of the armamentarium to treat abnormal hip–spine relationships.
-
Special attention should be directed to patients with adult spine deformity or fused spine because they are at increased risk of complications after THA.