June 17, 2010
Drs. Kevin Ong and Steve Kurtz from Exponent's Biomechanics/Medical Device Practice in Philadelphia, and Mr. Edmund Lau from Exponent's Center for Epidemiology and Computational Biology in Menlo Park, recently published a paper in Clinical Orthopaedics & Related Research, a publication of the Association of Bone and Joint Surgeons. The paper, "Risk of Subsequent Revision after Primary and Revision Total Joint Arthroplasty", addressed the relative risk of rerevision and risk factors that can help identify patients at high risk who may require closer postsurgical care after revision total joint arthroplasty which is technically more demanding than primary total joint arthroplasty (TJA).
The research evaluated the risk of subsequent revision after primary and revision TJA in the elderly (65 years or older) patient population and identified corresponding patient risk factors. Using the 5% Medicare claims data set (1997–2006), a total of 35,746 patients undergoing primary Total Hip Arthroplasty (THA) and 72,913 undergoing primary Total Knee Arthroplasty (TKA) were identified. From this data, 1,205 who had THAs and 1,599 who had TKAs underwent initial revision surgery. The rerevision rate after primary and revision TJAs was analyzed by the Kaplan-Meier method. The relative risk of revision surgery for primary and revision TJAs was compared using hazard ratio analysis.
The 5-year survival probabilities were 95.9%, 97.2%, 81.0%, and 87.4% for primary THA and TKA and revision THA and TKA, respectively. Patients with revision arthroplasty were five to six times more likely to undergo rerevision (adjusted relative risk, 4.89 for THA; 5.71 for TKA) compared with patients with primary arthroplasty. Age and comorbidities were associated with initial revision after primary THA and TKA.
The results showed that patients should undergo stringent preoperative screening for preexisting health conditions and careful patient management and followup postoperatively so as to minimize the risk of an initial revision, which otherwise could lead to a significantly greater likelihood of subsequent rerevisions.
The abstract and the article can be found here (registration required).