Orthopedic implants are made from different metal and plastic alloys, and are known to shed particles as a function of time and usage of the prosthetic joint. Analysis of the register data have demonstrated that factors such as design of the implant, type of alloy and usage of cement influence the survival time of the prosthesis [2, 10]. As the implants and surgical procedures has improved, so has the survival time of the prosthesis, but still a conservative estimate shows that more than 10% of all primary arthroplasties are revised within 15 years [1,2]. Factors such as younger age and male sex are associated with increased risk of revision, but patient age and sex do not influence the outcome of pain .
Orthogenics has identified a specific biomarker that is persistently detected in synovial tissue of the joint and correlate strongly with prosthesis failure. The biomarker is detected in several joint tissues with a high degree of reproducibility, and detection is strongly associated to specific mediators of inflammation.
The biomarker is strongly associated with a pro-inflammatory signature also found in synovial tissue, involving recruitment and activation of inflammatory cells to sites with osteolysis. Specific features of the disease process can be identified in blood samples not only by directly measuring pro-inflammatory signature proteins but also by analysis of gene expression and related molecular signaling pathways.
Development of immunodiagnostic detection tools, targeting the identified disease specific biomarkers in blood, facilitates an indirect detection of the pathology in the PL joint with no need for invasive tissue sampling.
The main scientific challenge ahead of us is to accurately confirm the correlation between the biomarker found in joint tissue to biological signatures in blood, and relate this to patient outcome, pain, function scores and survival time of the prosthesis.
This effort is expected to generate a prototype diagnostic test that will aid the identification of patients with aseptic PL due to osteolysis, and further generate documentation on how this test may allow early identification of these patients. It is anticipated that this innovation will be implemented for clinical use to aid clinicians in identification of surgical candidates and at-risk patients, who need increased attention and specialized treatment to stop or delay PL. The innovation will further allow clinical trials of novel therapies in the field of prosthesis loosening.