Abstract
Correct interaction between the spine, pelvis, and hip is an essential condition for
successful progress after total hip replacement. Spinal pathologies, such as degeneration,
fractures,
and spinopelvic imbalance with and without lumbar fusions, are closely associated
with an increased risk of impingement or even dislocation of the prosthesis. To significantly
reduce this
risk, various parameters are required to quantify the risk groups. Knowledge on the
presence of stiffness of the spine (change in pelvic tilt between standing and sitting
at < 10°) and
sagittal spinal deformity (pelvic incidence–lumbar lordosis mismatch > 10° or 20°)
is essential in identifying patients with corresponding risk. The individual risk
profile can be
assessed through a specific history and examination. Before total hip arthroplasty,
a routine preoperative workup is recommended for high-risk patients: using information
from standardised
preoperative radiographs while sitting and standing (pelvis, anteroposterior view,
lying and standing; spine and pelvis, lateral view, standing and sitting). Important
changes can be made
during the surgery. If the spine is stiff, attention should be paid to the position
of the cup, with increased anteversion, sufficient offset, and larger head that is
secure to dislocation –
to reduce the risk of dislocation. In the case of a sagittal spinal deformity, the
functional coronary pelvic level must be carefully controlled so that it is better
to use double mobility
cups. Digital systems, such as navigation and robotics, can optimise component positioning
although, so far, there is little evidence that the complication rate decreased. Therefore,
further
studies are warranted.
Key words
Hip-spine syndrome - total hip arthroplasty - dislocation - cup position - pelvic
tilt
