Total Hip Arthroplasty with a Cementless Acetabular Component and Impaction Bone Grafting for Dysplastic Osteoarthritis Complicated by Multiple Myeloma.

Total hip arthroplasty (THA) for pathologic and impending fracture due to periacetabular multiple myeloma (MM) lesions has been reported. We report a case of radiographic progression of dysplastic osteoarthritis, complicated by periacetabular MM lesions, treated by THA. A 69-year-old female with a 13-year history of MM presented with right hip pain. Plain radiographs and CT showed that dysplastic osteoarthritis had progressed, while the periacetabular MM lesions remained unchanged. Pathologic fracture was not observed on MRI. THA with a cementless acetabular component and impaction bone grafting was done. Bone graft incorporation was confirmed on CT at 1 year after surgery. There were no signs of bone absorption or implant loosening at last follow-up 3 years after surgery. Due to the advances in the treatment of MM and antiresorptive drugs, cementless acetabular component and impaction bone grafting may be an option for dysplastic osteoarthritis complicated by acetabular bone loss due to MM.