Adding false-profile radiographs improves detection of developmental dysplasia of the hip, data from the CHECK cohort

Abstract

The aim of this study was to determine the additional value of the false-profile (FP) view radiograph in the diagnosis of developmental dysplasia of the hip (DDH), as compared with an anteroposterior (AP) pelvic radiograph only, and evaluate the correlation between the Wiberg-lateral center edge angle (W-LCEA) and Wiberg-anterior center edge angle (W-ACEA). We used baseline data from a nationwide prospective cohort study (Cohort Hip and Cohort Knee). DDH was quantified on AP pelvic and FP hip radiographs using semi-automatic measurements of the W-LCEA and W-ACEA. A threshold of <20° was used to determine DDH for both the W-LCEA and the W-ACEA. The proportion of DDH only present on the FP view determined the FP view additional value. The correlation between the W-LCEA and W-ACEA was determined. In total 720 participants (1391 hips) were included. DDH was present in 74 hips (5.3%), of which 32 were only present on the FP view radiograph (43.2%). The Pearson correlation coefficient between W-LCEA and W-ACEA of all included hips was 0.547 (95% confidence interval: 0.503–0.591) and 0.441 (95% confidence interval: 0.231–0.652) in hips with DDH. A mean difference of 9.4° (SD 8.09) was present between the W-LCEA and the W-ACEA in the hips with DDH. There is a strong additional value of the FP radiograph in the diagnosis of DDH. Over 4 out of 10 (43.2%) individuals’ DDH will be missed when only using the AP radiograph. In hips with DDH a moderate correlation between W-LCEA and W-ACEA was calculated indicating that joints with normal acetabular coverage on the AP view can still be undercovered on the FP view.

Determining anterior hip coverage in patients with hip dysplasia using the anterior center-edge angle on Lequesne’s false-profile radiograph and on computed tomography

“…Based on their different characteristics, ACEA FP could be more suitable for determining anterior hip stability [ 18–20 ] because ACEA FP was taken in a standing position. That is the position in which the patient’s hip joint is actually performing its weight-bearing function [ 21 ]. While ACEA CT describes the morphology of the anterior hip joint more precisely, it is more suitable for evaluating the potential impingement which may occur after hip reorientation [ 19 , 22–25 ].…”

Anterior Center-Edge Angle Is Less Reliable Than Anterior Wall Index to Predict Anterior Coverage of the Femoral Head

“…8,22 A recent multicenter prospective cohort study suggested that obtaining a false-profile radiograph adds strong value to the diagnosis of hip dysplasia in the young adult in cases that would otherwise remain missed with a single anteroposterior view. 12 However, Herfkens et al 12 have emphasized that the Lequesne view is often unsuitable because of superimposition of osseous structures caused by alterations in tilt and rotation (of both the acetabulum and the femur), which cannot be adjusted for as in an anteroposterior view. Different studies have used ACEA to understand outcomes and prognosis after surgical treatment of femoroacetabular impingement and hip dysplasia.…”

Pincer Morphology Is Not Associated With Hip Osteoarthritis Unless Hip Pain Is Present: Follow‐Up Data From a Prospective Cohort Study

“…Next, a vertical line is drawn perpendicular to a horizontal reference line connecting both femoral heads (Figure 2). The LCEA is the angle between the vertical line and a line drawn from the center of the femoral head to the lateral acetabular rim 32,33 . The ACEA is constructed from the FP radiograph in a similar way, except that the vertical line is drawn perpendicular to the horizontal line of the radiographic film (Figure 3).…”

“…The LCEA is the angle between the vertical line and a line drawn from the center of the femoral head to the lateral acetabular rim. 32,33 The ACEA is constructed from the FP radiograph in a similar way, except that the vertical line is drawn perpendicular to the horizontal line of the radiographic film (Figure 3). 29,34 Pincer morphology was defined as LCEA ≥ 40 , ACEA ≥ 40 , or both the ACEA and LCEA ≥ 40 .…”