It is delimited by the upper limit of the femoral head superiorly and the anterior acetabular wall inferiorly. The upper medial zone shows the highest bone density due to the superimposition of both acetabular walls on the upper femoral head. The radiological density of the femoral head can be divided into 3 zones, reflecting the superimposition of the anterior and posterior acetabular walls and their oblique orientation ( Fig. 6 ). The head is partially covered by the acetabulum, which is obliquely oriented in the coronal and axial planes. The femoral head varies in thickness due to its spherical shape and it contains a thin sclerotic line that corresponds to the remnant of the physis (also called the physeal scar). The radiographic appearance of the hip joint is largely influenced by its anatomy. The physician interpreting conventional hip radiographs should first focus on alterations in radiological bone density. Normal Radiological Density of the Femoral Head Other limitations of conventional radiography of the hip include limited sensitivity for the detection of trabecular bone and medullary changes and the inability to show joint effusion ( Fig. 5 ). Because conventional radiography corresponds to a bidimensional projection of 3-D structures, however, it can only detect cortical changes to which the x-ray beam is tangent (see Figs. ( H, I ) Greater trochanter ( asterisk ) superimposed on the femoral neck ( thick arrow ) the lesser trochanter ( thin arrow ) also is seen.Ĭonventional radiography yields a high spatial resolution that enables detecting subtle changes in cortical contours and joint space width. The posterior ( thick arrow ) and the anterosuperior ( arrowhead ) aspects of the joint space are adequately depicted. ( F, G ) Anterior acetabular rim ( thin arrow ). ( D, E ) The anterior acetabular wall ( thick arrow ), acetabular fossa ( thin arrow ), and the ischiopubic ramus ( asterisk ). ( B, C ) Pubic bone ( asterisk ) and the iliopubic ramus ( arrows ). ( A ) Off-lateral view (Lequesne false profile) of the left hip and ( B, D, F, H ) corresponding sagittal CT reformats with ( C, E, G, I ) schematic drawings, from anterior to posterior. Poor evaluation of acetabulum and joint space Not for evaluation of joint space and acetabulum True lateral neck of femur (cross-table lateral view) The greater trochanter can obscure the head-neck anatomy. Profiles the head-neck junction adequatelyĪnterior and posterior aspects of the joint space are not evaluatedĤ5° posterior oblique, (Lauenstein projection)Įvaluation of the ilioischial column and anterior acetabular rimĮvaluation of the posterior acetabular rim and the iliopubic column Off lateral view (Lequesne false profile)Įvaluation of the anterior and posterior joint spaceĪllows a comparison with the contralateral side It allows analyzing the most anterior and posterior aspects of the joint space that are not depicted on the AP and the other lateral radiographs, at the expense of a decrease in the overall quality of the image.

The off-lateral view (also called false profile of Lequesne) is a unique radiograph that provides an evaluation of the hip joint in a near sagittal plane, with the femur in an anatomic position ( Fig. 4 ). Most of the lateral radiographs are obtained with different degrees of hip abduction and flexion providing a lateral view of the proximal femur. Several different lateral views of the hip can be obtained, the choice of which may depend on the clinical situation ( Fig. 3, Table 1 ). In the authors’ institution, an AP hip radiograph usually is obtained because of the high quality of the bony details secondary to beam collimation.

The added value of an AP hip radiograph to complement pelvic radiograph is open to debate except after total hip replacement. Standing hip radiograph does not provide additional information on the joint space except in severe hip dysplasias, opposite to the knee joint, for which proper assessment of the joint space width requires weight-bearing radiographs. When obtained in a standing position, it enables detecting leg length discrepancy but provides a less satisfactory analysis of the bone structure. The AP pelvic radiograph should be obtained with the patient lying supine, the lower limbs medially rotated (20 degrees). Moreover, by allowing the comparative analysis of both hips, it enhances the detection of subtle bone and joint abnormalities. The pelvic radiograph allows the assessment of the entire pelvic girdle, providing an overview of the entire region. Radiological work-up of the hip includes an anteroposterior (AP) radiograph of the pelvis and a lateral radiograph of the symptomatic hip.

Xray normal hip lat