Etiology |
Mechanical abrasion of metal surfaces causing microscopic debris with associated inflammatory response. |
Incidence |
Exact incidence is unknown [5], but has been reported at 23% after TKA with metal- backed patellar components [6] (which are no longer in common use). |
Gender ratio |
No known gender predilection. |
Age predilection |
Older patients (related to presence of arthroplasties in this population). |
Risk factors |
Biomechanical stresses on polyethylene liner insert that can lead to excess wear [6]. |
Treatment |
Surgical debridement, arthroplasty revision depending on extent of involvement |
Prognosis |
Good if early arthroplasty revision to prevent progressive joint destruction |
Findings on imaging |
Metal-line sign, bubble sign, cloud sign; periprosthetic osteolysis; often a joint effusion. |