Learning objectives
To review the different types of hip replacement.
To illustrate imaging findings in the evaluation of prostheses,
emphasizing useful data for the orthopedic surgeon.
To describe normal postoperative imaging findings and signs of complications.
To review the most important topics to report.
Background
Hip joint replacement surgery has been one of the most common type of orthopedic operation for nearly 25 years,
with approximately 1 million hip arthroplasties performed worldwide annually.
Types of hip replacements
There are two general types of hip replacements,
hemiarthroplasty and Total Hip Arthroplasty (THA).
Hemiarthroplasty
Refers to replacement of only the femoral side of the hip joint.
This type of prosthesis is indicated when the native acetabulum is unaffected.
A unipolar hemiarthroplasty consists of a femoral stem with a fixed head,
which articulates...
Findings and procedure details
Analysis of a hip arthroplasty
Evaluation of the arthroplasty should include a frontal view of the pelvis,
either a “frog leg” or cross-table lateral.
Radiographs must include a margin around the prosthesis to evaluate the adjacent bony and soft tissue estructures.
Initial placement of the prosthetic components should mimic the normal positions of the native acetabulum and femoral head and neck.
Specific anatomical landmarks and measurements are used to verify correct placement.
The initial evaluation,
should include: leg length,
vertical and horizontal centre of rotation,...
Conclusion
Hip arthroplasty has become the standard treatment for end-stage hip disease.
Despite improved longevity,
the majority of implants eventually have complications with time.
Owing to the increasing utilization and evolution of materials,
techniques and numbers of hip arthroplasty procedures performed,
this technique becomes more challenging for radiologist evaluation.
There is also a growing demand for an accurate diagnosis of symptoms related to hip arthroplasty implants and for a way to monitor patients at risk.
The demonstration and characterization of arthroplasty-related complications contribute important information for...