PMC5591987_01
AP radiograph demonstrating eccentric positioning of the femoral head component of the right total hip arthroplasty without evidence for subsidence of the stem and loosening of the components.
CRIOR2017-9123684.001.jpg
PMC5591987_01_CRIOR2017-9123684.001.jpg
fig1
Plain radiographs demonstrated a normal configuration of the acetabular component, albeit with an eccentric positioning of the head within the socket; there was no evidence for osteolytic lesions, subsidence of the stem, or loosening of the components (Figure 1).
AP radiograph, 6 weeks following revision arthroplasty, demonstrating a polyethylene cup combined with a cobalt-chromium (CoCr) femoral head.
CRIOR2017-9123684.002.jpg
PMC5591987_01_CRIOR2017-9123684.002.jpg
fig2
The acetabular shell was removed and replaced by a polyethylene (PE) SHP cup (Scientific Hip Prosthesis; Biomet, Warsaw, Indiana, USA) combined with a 28 mm cobalt-chromium (CoCr) alloy femoral head, with a matching taper (Figure 2).
AP radiograph, one year postoperative. Periarticular densities around all components with flattening of the femoral head.
CRIOR2017-9123684.003.jpg
PMC5591987_01_CRIOR2017-9123684.003.jpg
fig3
Additional plain radiographs showed a well-fixed reversed hybrid total hip prosthesis and impressive periarticular densities around the components combined with flattening of the femoral head component with loss of its sphericity (Figure 3).
MARS-MRI of the right hip with metal wear debris with comprehensive pseudotumor formation (arrow).
CRIOR2017-9123684.004.jpg
PMC5591987_01_CRIOR2017-9123684.004.jpg
fig4
Therefore, a magnetic resonance image (MRI) with metal artefact reduction sequence (MARS) was obtained which demonstrated metal wear debris with comprehensive pseudotumor formation surrounding the components of the total hip prosthesis (Figure 4).