Diagnosis and Treatment of Adverse Local Tissue Reactions at the Head-Neck Junction.

Modular junctions in total hip arthroplasty are susceptible to mechanically assisted crevice corrosion, leading to the release of metal wear debris. Adverse local tissue reactions result from an immune-mediated biological reaction to this debris and can have a profound effect on the surrounding periarticular soft tissue envelope. Patients often present with pain or muscle weakness and demonstrate elevated serum cobalt and chromium levels. Serum inflammatory markers and synovial fluid tests help distinguish these reactions from deep infection in the majority of cases; however, the presence of amorphous material or fragmented cells can lead to difficulty in some cases. Advanced cross-sectional imaging is essential in establishing the diagnosis. Early revision surgery is generally the treatment of choice for symptomatic adverse local tissue reaction from corrosion at the modular head-neck junction. The existing stem is retained, and a new ceramic head is placed on the existing trunnion whenever possible. This strategy generally leads to short-term improvement of symptoms with reliable clinical outcomes; however, longer term results are presently lacking.