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Pseudoacetabulum a subtle radiological feature of a chronic dislocated total hip replacement
Saurabh Odak1, Jitendra Mangwani, John Ivory
1Royal Liverpool University Hospital, Warrington, UK. saurabhsodak@gmail.com
BMJ Case Reports
|October 10, 2012
Summary
A rare pseudoacetabulum formed in a dislocated total hip arthroplasty due to heterotopic ossification. This unusual finding indicates chronic hip instability and dislocation in patients.
Area of Science:
- Orthopedic Surgery
- Radiology
- Medical Imaging
Background:
- Total hip arthroplasty (THA) is a common procedure to address hip joint issues.
- Chronic dislocation of THA can lead to significant complications.
- Heterotopic ossification (HO) is the abnormal formation of bone in soft tissues.
Observation:
- A case of an elderly patient with a dislocated and asymptomatic total hip arthroplasty was observed.
- Radiographs revealed a unique pseudoacetabulum formation around the dislocated femoral head.
- Previous imaging confirmed heterotopic ossification in the surrounding soft tissues.
Findings:
- The dislocated femoral head was encased by a well-defined, radio-opaque shadow, forming a pseudoacetabulum.
- This radiological feature was associated with chronic instability and previous dislocations.
- Successful reduction of the dislocated joint was achieved under general anesthesia.
Implications:
- Pseudoacetabulum formation is a significant radiological sign of chronic instability after total hip arthroplasty.
- Recognizing this feature aids in diagnosing and managing complications of hip arthroplasty.
- Understanding the role of heterotopic ossification in pseudoacetabulum development is crucial for orthopedic surgeons.
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