Utility of Upright Weight-bearing Imaging in Total Hip Arthroplasty

Abstract

Planning for total hip arthroplasty (THA) has traditionally been performed using static supine anteroposterior radiographs of the pelvis. Recent advances in imaging technology and the understanding of human spinopelvic kinematics have made weight-bearing radiography an important adjunct to supine imaging. Hip surgeons can use weight-bearing imaging to optimize THA component position to prevent hip instability and early component wear. The goal of this narrative review is to delineate the fundamentals of spinopelvic kinematics, the benefits of surgical planning using weight-bearing radiography, and the underpinnings of upright full-body stereoradiography as a useful adjunct to traditional supine radiographs.

Effects of pelvic obliquity and limb position on radiographic leg length discrepancy measurement: a Sawbones model

“…Despite this, surgical planning for THA has traditionally preferred supine AP radiographic images of the pelvis. Standing images, when obtained, are typically used as an adjunct and not a replacement for supine imaging [ 43 ]. This is largely attributable to the significant differences in pelvic tilt and acetabular anteversion and inclination seen between supine and standing positions [ 43 ].…”

“…For patients requiring absolute precision, magnification markers of known diameter can be positioned along the patient’s coronal plane at the level of the greater trochanter [ 45 ]. The X-ray beam itself is commonly centered on a point midway between the superior border of the patient’s pubic symphysis and a line drawn connecting the anterior superior iliac spines [ 43 , 46 ]. Lowering the X-ray beam to be aligned centered near the pubis ensures that the whole proximal third of the femurs are visible and are more or less located in the same horizontal plane as the X-ray source.…”

“…Standing images, when obtained, are typically used as an adjunct and not a replacement for supine imaging [43]. This is largely attributable to the significant differences in pelvic tilt and acetabular anteversion and inclination seen between supine and standing positions [43]. If tilt or rotation of the pelvis is evident with the patient lying supine, suspicion and diagnosis of hip contracture or lumbosacral pathology is more readily established [27].…”