E1240. Postoperative Hip: Radiographic Review of Common Surgical Interventions and Their Complications
  1. Benjamin Reeves; University of Alabama at Birmingham
  2. Rachel Bass; University of Alabama at Birmingham
  3. Mason Frazier; University of Alabama at Birmingham
  4. Yulia Melenevsky; University of Alabama at Birmingham
Radiography is recommended by the American College of Radiology (ACR) Appropriateness Criteria as the initial imaging modality of choice in the postoperative setting, following surgical interventions on the hip. Over 800,000 hip arthroplasties were performed in the United States in 2020, and this number is projected to increase. As such, while postoperative complications are overall uncommon, they are routinely encountered in a busy clinical practice. Recognition of complications on routine screening and diagnostic radiographs have important clinical implications, and some more subtle or less common abnormalities may be easily missed by an unexperienced radiologist. This educational exhibit comprehensively reviews the radiographic appearance of surgical interventions on the hip for degenerative disease, trauma, and osteonecrosis, as well the radiographic appearance of complications and their clinical implications.

Educational Goals / Teaching Points
The goal of this educational exhibit is to review radiographic appearances of commonly performed surgical interventions of the hip in the treatment of degenerative disease, osteonecrosis, trauma, and prior hardware failure with revision. This exhibit will educate radiologists on the radiographic appearance of immediate and delayed complications, and highlight less common but important complications such as metallosis, displaced acetabular liner, and disruption of the retainer wire, along with the clinical implications.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Radiographic cases of complications following primary and revision hip arthroplasty in this exhibit include periprosthetic fracture of the femoral shaft and trochanters, hardware malposition, hardware failure, particle disease, and infection. Cases of other less commonly encountered complications such as metallosis and dislocation of the non-radiopaque acetabular liner are also presented, as they can be missed or misinterpreted with important clinical implications. This exhibit also reviews cases of post-traumatic fixation complications including femoral neck fracture subsidence with intra-articular migration of a compression screw, femoral head osteonecrosis following femoral neck fracture fixation, and acetabular hardware failure. Finally, a case of worsening osteonecrosis following core decompression with subsequent collapse is presented.

Radiographs are commonly performed in the postoperative evaluation of the hip. Understanding the common, immediate, and delayed postoperative complications are imperative to identify obvious and subtle findings that affect clinical management.