Periprosthetic osteolysis: an immunologist's update

Area of Science:

• Orthopedics and Biomedical Engineering
• Immunology and Drug Development

Background:

• Inflammation-induced osteolysis is a significant challenge in inflammatory arthritis and total joint arthroplasty.
• While drug therapies have advanced for inflammatory arthritis, periprosthetic osteolysis treatment remains limited.

Purpose of the Study:

• To provide an updated review of the current state of periprosthetic osteolysis.
• To highlight recent advancements in understanding, imaging, and therapeutic development for osteolysis.

Main Methods:

• Review of preliminary clinical trial data for AMG-162, a RANK ligand inhibitor.
• Analysis of validated volumetric 3D and MRI imaging techniques for osteolysis quantification.
• Examination of immunological findings, including lymphocytic infiltrates, cobalt allergy, and T helper cell subsets (e.g., IL-17 secreting cells).

Main Results:

• AMG-162 demonstrates safety and potent osteoclast inhibition in early trials, with potential for treating inflammation-induced osteolysis.
• Advanced imaging techniques are validated for detecting and quantifying periprosthetic osteolysis.
• Evidence suggests a potential role for metal allergy and newly discovered T helper cells in periprosthetic osteolysis.

Conclusions:

• Significant progress has been made in understanding periprosthetic osteolysis.
• Developments in imaging technology and drug discovery offer new avenues for treatment.
• Clinical translation of these advances is now feasible and recommended.