Clinical History, Examination and Blood Test Results

  • Step 3 case 1 is a 61-year-old female who presented with bilateral painful Birmingham hip resurfacings in 2012. Primary hip operations were done in 2004. She had night pain in both hips.

  • Examination revealed an antalgic and slow gait.

  • CRP was 5 mg/L. Blood metal ion levels were raised.


Imaging Results

PRE-OP RADIOGRAPH

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This is an anteroposterior (AP) pre-operative radiograph demonstrating bilateral metal on metal hip resurfacings. There is osteolysis surrounding both of the implants, which was better quantified on computer tomography (CT) scan.

 

Diagnosis

  • Painful bilateral metal-on-metal Birmingham hip replacements secondary to metal ion induced synovitis and osteolysis causing micromovement of the components and bone pain.

    Revision is needed to avoid periprosthetic fracture.


Treatment

  • In April 2013 she had a revision of her right Birmingham hip resurfacing with acetabular allograft of bone defects, and a porous metal cup secured with two iliac screws.

  • In August 2013 she then had her left hip revised, however no bone grafting was required.


Imaging Outcomes

POST-OP RADIOGRAPH

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This post-operative AP radiograph of the pelvis from April 2014 demonstrates the bilateral revision with acetabular bone graft on the right hand side.

 

Clinical Outcomes

  • She returned to all normal daily activities within 6 months of revision surgery on both sides.

  • 12 months post-operative she attended aquafit classes three times a week and used the cross-trainer and exercise bike.


Learning Points

  • Metal on metal hips were introduced to solve the problem of polyethylene-induced osteolysis, however in some patients the osteolysis from MOM hips is severe within 10 years of the primary operation. Follow up with an AP plain radiograph at regular 3 yearly intervals after 5 years post operative will avoid uncontrolled osteolysis and allow straightforward revision surgery with good clinical outcome.