Hip replacement

The world of orthopaedics is continuously evolving with advancements that promise increased patient mobility and quality of life. One such advancement is total hip arthroplasty (THA), commonly known as hip replacement surgery. Despite the general success of this procedure, complications such as aseptic loosening (AL) and periprosthetic joint infection (PJI) can arise, necessitating meticulous diagnostic and management strategies. A seminal study published in the “Journal of Clinical Orthopaedics and Trauma” sheds light on the efficacy of joint aspirations in detecting PJI in cases with normal serological markers [DOI:10.1016/j.jcot.2018.09.011].

This article aims to provide an in-depth review of the recent research led by Erik E. Schiffner et al. from the Department of Trauma and Handsurgery, Heinrich Heine University Duesseldorf, and its implications for orthopaedic practice. Our focus will elaborate on the study’s design, findings, and contributions to the field of orthopaedic surgery, addressing the critical question: Do patients showing signs of loosening after THA, but with normal C-reactive protein (CRP) and white blood cell (WBC) counts, need a joint aspiration to rule out PJI?

The Study at a Glance

The study included 108 symptomatic patients with radiographic signs of prosthetic loosening and hip pain after undergoing THA. Patients underwent standardized serological testing and preoperative joint aspirations. Intraoperatively, samples for microbiological testing were taken and compared against the gold standard for differential diagnosis. Among the patients, 85 were diagnosed with AL, and 23 with PJI. Interestingly, within the PJI subgroup, 44% had normal levels of CRP and WBC.

The Implications for Clinical Practice

The study highlights a critical aspect of post-THA management: the reliance on CRP and WBC levels to screen for infection must be reconsidered. As the authors note, despite normal serological results, a significant proportion of patients with clinical signs of loosening may indeed have PJI, which joint aspirations can successfully detect.

This finding has profound implications for clinical decision-making. Traditionally, elevated CRP and WBC counts are considered red flags for infection; however, this study suggests that serology alone cannot be the sole determinant of PJI. It underscores the importance of joint aspiration, a procedure where synovial fluid is extracted from the joint space for analysis, as a more reliable method for PJI detection.

The Value of Early and Accurate Diagnosis

Accurate diagnosis of joint infections is paramount. Delayed or misdiagnosis can lead to severe complications, including prolonged physical discomfort, additional surgeries, and a rise in healthcare costs. The effectiveness of joint aspirations, even when serological markers are normal, offers a pathway to more timely and precise diagnoses, improving patient outcomes.

In support of joint aspirations, it is essential to highlight the research by Caton et al. which demonstrated the long-term success of Charnley’s total hip arthroplasty, underscoring the significance of maintaining this success by preventing complications such as PJI [1]. Similarly, studies by Austin et al. shed light on the complexities of diagnosing periprosthetic infection [5], further solidifying the need for thorough diagnostics beyond serological markers.

Future Perspectives and Research

There is a growing recognition of the need for improved diagnostic algorithms that include joint aspirations. Continuing national and international discussions among orthopaedic experts and researchers to refine these protocols is necessary for enhanced patient care. Future research should focus on the development of more precise biomarkers for infection detection and the evaluation of other diagnostic tools complementary to joint aspirations.

Conclusion

The research by Schiffner et al. represents a pivotal point in orthopaedic diagnostics. As this study shows, reliance solely on CRP and WBC can be misleading in the evaluation of THA patients for PJI, warranting the additional step of joint aspiration. This practice offers a more comprehensive approach to diagnosing potential complications following hip replacement surgery and can protect the achievement of THA by minimizing the adverse outcomes related to PJI.

Keywords

1. Total Hip Arthroplasty Complications
2. Periprosthetic Joint Infection Diagnosis
3. Joint Aspiration Reliability
4. CRP WBC THA Screening
5. Diagnostic Algorithm for Hip Replacement

References

1. Caton, J., & Prudhon, J. L. (2011). Over 25 years survival after Charnley’s total hip arthroplasty. International Orthopaedics, 35(2), 185-188. doi:10.1007/s00264-010-1134-9
2. Austin, M. S. (2008). A simple, cost-effective screening protocol to rule out periprosthetic infection. The Journal of Arthroplasty, 23(1), 65-68. doi:10.1016/j.arth.2007.05.044
3. Nagoya, S. (2008). Diagnosis of peri-prosthetic infection at the hip using triple-phase bone scintigraphy. The Journal of Bone and Joint Surgery. British volume, 90(2), 140-144. doi:10.1302/0301-620X.90B2.20257
4. Chalmers, P. N., Sporer, S. M., & Levine, B. R. (2014). Correlation of aspiration results with periprosthetic sepsis in revision total hip arthroplasty. The Journal of Arthroplasty, 29(2), 438-442. doi:10.1016/j.arth.2013.08.023
5. Schiffner, E. E., Latz, D., Thelen, S., Grassmann, J. P., Karbowski, A., Windolf, J., Schneppendahl, J., & Jungbluth, P. (2019). Normal CRP and WBC values in total hip arthroplasty (THA) with signs of loosening. Do we need a joint aspiration? Journal of Clinical Orthopaedics and Trauma, 10(3), 566-570. doi:10.1016/j.jcot.2018.09.011