Figure 1
A 60-year-old man with ankylosing spondylitis. (A) X film showed a massive periprosthetic osteolytic lesion associated with huge soft tissue mass around a failed total hip replacement that has taken up the left periumbilical region. Pathological fracture occurred at the distal part of femoral stem. (B) CT scan confirmed huge soft tissue component in the pelvis. (C) We performed a hemipelvic amputation and non-significant polyethylene wear was detected. (D) Histology afterward revealed no sarcoma, but inflammatory tissue.