Background Revision surgery for failed total knee arthroplasty (TKA) continues to pose a substantial burden for the United States healthcare system. The predominant etiology of TKA failure has changed over time and may vary between studies. This report aims to update the current literature on this topic by using a large national database. Specifically, we analyzed: (1) etiologies for revision TKA; (2) frequencies of revision TKA procedures; (3) various demographics including payer type and region; and (4) the length of stay (LOS) and total charges based on type of revision TKA procedure. Methods The Healthcare Cost and Utilization Project (HCUP) National Inpatient Sample (NIS) database was used to identify all revision TKA procedures performed between 2009 and 2013. Clinical, economic, and demographic data were collected and analyzed for 337,597 procedures. Patients were stratified according to etiology of failure, age, sex, race, US census region, and primary payor class. The mean LOS and total charges were also calculated. Results Infection was the most common etiology for revision TKA (20.4%), closely followed by mechanical loosening (20.3%). The most common revision TKA procedure performed was all component revision (31.3%). Medicare was the primary payor for the greatest proportion of revisions (57.7%). The South census region performed the most revision TKAs (33.2%). The overall mean LOS was 4.5 days, with arthrotomy for removal of prosthesis without replacement procedures accounting for the longest stays (7.8 days). The mean total charge for revision TKAs was $75,028.07. Conclusion Without appropriate measures in place, the burden of revision TKAs may become overwhelming and pose a strain on providers and institutions. Continued insight into the etiology and epidemiology of revision TKAs may be the principle step towards improving outcomes and mitigating the need for future revisions.

Current Epidemiology of Revision Total Knee Arthroplasty in the United States

Total knee arthroplasty (TKA) is a cost effective and extremely successful operation. As longevity increases, the demand for primary TKA will continue to rise. The success and survivorship of TKAs are dependent on the demographics of the patient, surgical technique and implant-related factors. Currently the risk of failure of a TKA requiring revision surgery ten years post-operatively is 5%. The most common indications for revision include aseptic loosening (29.8%), infection (14.8%), and pain (9.5%). Revision surgery poses considerable clinical burdens on patients and financial burdens on healthcare systems. We present a current concepts review on the epidemiology of failed TKAs using data from worldwide National Joint Registries.

The epidemiology of failure in total knee arthroplasty: avoiding your next revision.

The number of revision Total Knee Arthroplasty (TKA) is rising in many countries. The aim of this study was the prospective assessment of the underlying causes leading to revision TKA in a tertiary care hospital and the comparison of those reasons with previously published data. In this study patients who had revision TKA between 2010 and 2015 were prospectively included. Revision causes were categorized using all available information from patients’ records including preoperative diagnostics, intraoperative findings as well as the results of the periprosthetic tissue analysis. According to previous studies patients were divided into early (up to 2 years) and late revision (more than 2 years). Additional also re-revisions after already performed revision TKA were included. We assessed 312 patients who underwent 402 revision TKA, 89.6% of them were referred to our center for revision surgery. In 289 patients (71.9%) this was the first revision surgery after primary TKA. Among the first revisions the majority was late revisions (73.7%). One hundred thirteen patients (28.1%) had already had one or more revision surgeries before. Overall, the most frequent reason for revision was infection (36.1%) followed by aseptic loosening (21.9%) and periprosthetic fracture (13.7%). In a specialized arthroplasty center periprosthetic joint infection (PJI) was the most common reason for revision and re-revision TKA. This is in contrast to population-based registry data and has consequences on costs as well as on success rates in such centers.

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Analysis of Total Knee Arthroplasty revision causes.

Although large series from national joint registries may accurately reflect indications for revision TKAs, they may lack the granularity to detect the true incidence and relative importance of such indications, especially periprosthetic joint infections (PJI) Using a combination of individual chart review supplemented with New Zealand Joint Registry data, we asked: (1) What is the cumulative incidence of revision TKA? (2) What are the common indications for revising a contemporary primary TKA? (3) Do revision TKA indications differ at various followup times after primary TKA? We identified 11,134 primary TKAs performed between 2000 and 2015 in three tertiary referral hospitals The New Zealand Joint Registry and individual patient chart review were used to identify 357 patients undergoing subsequent revision surgery or any reoperation for PJI All clinical records, radiographs, and laboratory results were reviewed to identify the primary revision reason The cumulative incidence of each revision reason was calculated using a competing risk estimator The cumulative incidence for revision TKA at 15 years followup was 61% (95% CI, 51%–71%) The two most-common revision reasons at 15 years followup were PJI followed by aseptic loosening The risk of revision or reoperation for PJI was 20% (95% CI, 17%–23%) and aseptic loosening was 12% (95% CI, 07%–16%) Approximately half of the revision TKAs secondary to PJI occurred within 2 years of the index TKA (95% CI, 08%–12%), whereas half of the revision TKAs secondary to aseptic loosening occurred 8 years after the index TKA (95% CI, 04%–07%) In this large cohort of patients with comprehensive followup of revision procedures, PJI was the dominant reason for failure during the first 15 years after primary TKA Aseptic loosening became more important with longer followup Efforts to improve outcome after primary TKA should focus on these areas, particularly prevention of PJI Level III, therapeutic study

/pdf/periprosthetic-joint-infection-is-the-main-cause-of-failure-t1k9i02089.pdf

Periprosthetic Joint Infection Is the Main Cause of Failure for Modern Knee Arthroplasty: An Analysis of 11,134 Knees.

Background Arthrofibrosis is a debilitating postoperative complication of total knee arthroplasty (TKA). It is one of the leading causes of hospital readmission and a predominant reason for TKA failure. The prevalence of arthrofibrosis will increase as the annual incidence of TKA in the United States rises into the millions. Methods In a narrative review of the literature, the etiology, economic burden, treatment strategies, and future research directions of arthrofibrosis after TKA are examined. Results Characterized by excessive proliferation of scar tissue during an impaired wound healing response, arthrofibrotic stiffness causes functional deficits in activities of daily living. Postoperative, supervised physiotherapy remains the first line of defense against the development of arthrofibrosis. Also, adjuncts to traditional physiotherapy such as splinting and augmented soft tissue mobilization can be beneficial. The effectiveness of rehabilitation on functional outcomes depends on the appropriate timing, intensity, and progression of the program, accounting for the patient's ability and level of pain. Invasive treatments such as manipulation under anesthesia, debridement, and revision arthroplasty improve range of motion, but can be traumatic and costly. Future studies investigating novel treatments, early diagnosis, and potential preoperative screening for risk of arthrofibrosis will help target those patients who will need additional attention and tailored rehabilitation to improve TKA outcomes. Conclusion Arthrofibrosis is a multi-faceted complication of TKA, and is difficult to treat without an early, tailored, comprehensive rehabilitation program. Understanding the risk factors for its development and the benefits and shortcomings of various interventions are essential to best restore mobility and function.

Arthrofibrosis Associated With Total Knee Arthroplasty

article i nfo The purpose of this study was to determine the frequency and cause of failure after total knee arthroplasty and compare the results with those reported by our similar investigation conducted 10 years ago. A total of 781 revision TKAs performed at our institution over the past 10 years were identified. The most common failure mechanisms were: loosening (39.9%), infection (27.4%), instability (7.5%), periprosthetic fracture (4.7%), and arthrofibrosis (4.5%). Infection was the most common failure mechanism for early revision (b2 years from primary) and aseptic loosening was the most common reason for late revision. Polyethylene (PE) wear was no longer the major cause of failure. Compared to our previous report, the percentage of revisions performed for polyethylene wear, instability, arthrofibrosis, malalignment and extensor mechanism deficiency has decreased. © 2014 Published by Elsevier Inc.

Why Are Total Knee Arthroplasties Failing Today—Has Anything Changed After 10 Years?

Revision total knee arthroplasty (TKA) in the setting of bone deficiency requires varied levels of constraint to restore knee stability. However, the outcomes between different levels remain controversial. Clinical outcomes for 183 AORI Type I knees, 168 Type II knees and 124 Type III knees utilizing posterior stabilized (PS), unlinked constrained (UC) or hinged prostheses were evaluated with standardized clinical assessment tools and radiographic results over an average of 7.4 years. PS yielded superior knee scores in AORI Type I patients (P<0.05), UC in Type II and III aseptic patients (P<0.05), and a hinge was preferred in septic Type II or III knees (P<0.05). Revision TKA conducted with increased constraint appears effective in the setting of increased bone deficiency.

Revision Knee Arthroplasty for Bone Loss: Choosing the Right Degree of Constraint

Mechanical strength and corrosion resistance are needed for Mg based BMs in the application of biomedical fields. In the present study, a high-strength biodegradable Mg-Gd alloys with an ultrafine microstructure successfully were prepared by equal channel angular pressing (ECAP). The high tensile strength of ECAPed Mg-Gd alloys was attributed to ultrafine DRX grains and fragmented secondary phases. During ECAP, the grain structure was refined by dynamic recrystallization (DRX), and the size of the DRX grains was approximately 300 nm. The secondary phase with lamellar structures was fragmented into fine particles of submicrometer size after ECAP process. As the number of ECAP passes increased, the distribution of the fragmented secondary phase has been changed into a uniform distribution. The corrosion rates calculated from the hydrogen evolution test demonstrated that the 8p-ECAP Mg-Gd alloy with an ultrafine microstructure possessed better corrosion resistance. Cell and osteogenesis induction experiments confirmed that Mg-Gd alloys processed by ECAP exhibited good biocompatibility. This study provides a new method for preparing high-strength Mg alloys with good corrosion resistance and biocompatibility.

https://iopscience.iop.org/article/10.1088/2053-1591/acc0e0/pdf

Chao Shen

Papers

Why Are Total Knee Arthroplasties Failing Today—Has Anything Changed After 10 Years?

Revision Knee Arthroplasty for Bone Loss: Choosing the Right Degree of Constraint

Preparing high-strength and osteogenesis-induced Mg-Gd alloy with ultra-fine microstructure by equal channel angular pressing