Clinical Outcomes Following Revision Total Knee Arthroplasty: Minimum 2-Year Follow-up

Can individual functional improvements be predicted in osteoarthritic patients after total knee arthroplasty?

PURPOSE

Total knee arthroplasty (TKA) is an effective treatment for advanced osteoarthritis, and achieving optimal outcomes can be challenging due to various influencing factors. Previous research has focused on identifying factors that affect postoperative functional outcomes. However, there is a paucity of studies predicting individual postoperative improvement following TKA. Therefore, a quantitative prediction model for individual patient outcomes is necessary.

MATERIALS AND METHODS

Demographic data, radiologic variables, intraoperative variables, and physical examination findings were collected from 976 patients undergoing TKA. Preoperative and 1-year postoperative Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were assessed, and multivariate regression analysis was conducted to identify significant factors influencing one-year WOMAC scores and changes in WOMAC scores. A predictive model was developed on the basis of the findings.

RESULTS

The predictive accuracy of the model for 1-year WOMAC scores was poor (all adjusted R2 < 0.08), whereas the model for changes in WOMAC scores demonstrated strong predictability (all adjusted R2 > 0.75). Preoperative WOMAC scores, sex, and postoperative knee range of motion significantly affected all pain, stiffness, and physical function aspects of the WOMAC scores (all P < 0.05). Age, cerebrovascular disease, and patellar resurfacing were associated with changes in physical function (all P < 0.05).

CONCLUSIONS

The developed quantitative model demonstrated high accuracy in predicting changes in WOMAC scores after TKA. The identified factors influencing postoperative improvement in WOMAC scores can assist in optimizing patient outcomes after TKA.

Big data analysis reveals significant increases in complications, costs, and hospital stay in revision total knee arthroplasty compared to primary TKA

INTRODUCTION

Despite significant advancements in total knee arthroplasty (TKA), some patients require revision surgery (R-TKA) due to complications such as infection, mechanical loosening, instability, periprosthetic fractures, and persistent pain. This study aimed to explore the specific causes leading to R-TKA, associated complications, including infection, mechanical failure, and wound issues, as well as costs, mortality rates, and hospital length of stay (LOS) using data from a large national database.

METHODS

Data from the nationwide inpatient sample (NIS), the largest publicly available all-payer inpatient care database in the United States were analysed from 1 January 2016 to 31 December 2019. The study included 44,649 R-TKA cases, corresponding to 223,240 patients, with exclusions for nonelective admissions. Various statistical analyses were used to assess clinical outcomes, including in-hospital mortality, postoperative complications, LOS, and hospitalization costs.

RESULTS

Among 2,636,880 TKA patients, 8.4% underwent R-TKA. R-TKA patients had higher rates of chronic conditions, including mental disorders (36.4%) and renal disease (9.9%). Additionally, these patients often experienced instability, necessitating revision surgery. Infection (22.3%) was the primary reason for R-TKA, followed by mechanical loosening (22.9%) and instability. Compared to primary TKA patients, R-TKA patients exhibited higher in-hospital mortality (0.085% vs. 0.025%), longer LOS (3.1 vs. 2.28 days), and higher total charges ($97,815 vs. $62,188). Postoperative complications, including blood transfusion (4.6% vs. 1.3%), acute kidney injury (4.4% vs. 1.8%), venous thromboembolism (0.55% vs. 0.29%), infection, and wound problems, were significantly higher in R-TKA patients.

CONCLUSIONS

This study provides detailed insights into t LOS, costs, and complications associated with specific etiologies of revision TKA. Our findings emphasize the need for targeted preoperative optimization and patient education. This approach can help reduce the incidence and burden of R-TKA, improve patient care, optimize resource allocation, and potentially decrease the overall rates of complications in revision surgeries.

LEVEL OF EVIDENCE

Level III.

Risk factors associated with re-revision following revision total knee arthroplasty: a systematic review

Aims

The aim of this study was to perform a systematic review and bias evaluation of the current literature to create an overview of risk factors for re-revision following revision total knee arthroplasty (rTKA).

Methods

A systematic search of MEDLINE and Embase was completed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The studies were required to include a population of index rTKAs. Primary or secondary outcomes had to be re-revision. The association between preoperative factors and the effect on the risk for re-revision was also required to be reported by the studies.

Results

The search yielded 4,847 studies, of which 15 were included. A majority of the studies were retrospective cohorts or registry studies. In total, 26 significant risk factors for re-revision were identified. Of these, the following risk factors were consistent across multiple studies: age at the time of index revision, male sex, index revision being partial revision, and index revision due to infection. Modifiable risk factors were opioid use, BMI > 40 kg/m2, and anaemia. History of one-stage revision due to infection was associated with the highest risk of re-revision.

Conclusion

Overall, 26 risk factors have been associated with an increased risk of re-revision following rTKA. However, various levels of methodological bias were found in the studies. Future studies should ensure valid comparisons by including patients with identical indications and using clear definitions for accurate assessments.

Risk factors for early septic failure after two-stage exchange total knee arthroplasty for treatment of periprosthetic joint infection

BACKGROUND

The cause of early septic failure after two-stage exchange revision total knee arthroplasty (TKA) for chronic periprosthetic joint infection (PJI) and the factors affecting it are not well known. The purpose of this study was to determine the surgical outcomes and the risk factors for early septic failure after two-stage revision TKA for chronic PJI.

METHODS

We identified a total of 246 adult patients who met the Musculoskeletal Infection Society (MSIS) diagnostic criteria for chronic PJI at two academic tertiary hospitals from March 2012 to December 2018. Finally, 151 patients who consecutively received two-stage exchange revision TKA for chronic PJI and who had a minimum 3-year follow-up were enrolled and retrospectively reviewed. Successful surgical treatment was evaluated for two-stage revision TKA and risk factors for early septic failure were identified.

RESULTS

Early septic failures occurred within 3 years after reimplantation in 48 patients (31.8%). After accounting for potentially confounding variables, we found that male patient [odds ratio (OR): 2.753, 95% confidence interval (CI) 1.099-6.893, p = 0.031], fungus or mycobacterial infection (OR: 5.224, 95% CI 1.481-18.433, p = 0.01), and positive culture at reimplantation (OR: 4.407, 95% CI 1.255-15.480, p = 0.021) were independently associated with early septic failure after two-stage exchange revision TKA.

CONCLUSION

Male patients, fungus or mycobacterial infection, and positive culture at reimplantation were independently associated with an increased risk of early septic failure after two-stage exchange revision TKA despite normal C-reactive protein values prior to reimplantation. Further prospective and high-quality studies are needed to determine the risk factors of two-stage exchange revision TKA for chronic PJI.

LEVEL OF EVIDENCE

level IV; retrospective comparison; treatment study.

A mapping review on preoperative prognostic factors and outcome measures of revision total knee arthroplasty

To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration. We performed a systematic literature search in MEDLINE, Embase, and Web of Science. The search string included multiple synonyms of the following keywords: "revision TKA", "outcome" and "prognostic factor". We searched for studies assessing the association between at least one prognostic factor and at least one outcome measure after rTKA surgery. Data on sample size, study design, prognostic factors, outcomes, and the direction of the association was extracted and included in an evidence map. After screening of 5,660 articles, we included 166 studies reporting prognostic factors for outcomes after rTKA, with a median sample size of 319 patients (30 to 303,867). Overall, 50% of the studies reported prospectively collected data, and 61% of the studies were performed in a single centre. In some studies, multiple associations were reported; 180 different prognostic factors were reported in these studies. The three most frequently studied prognostic factors were reason for revision (213 times), sex (125 times), and BMI (117 times). Studies focusing on functional scores and patient-reported outcome measures as prognostic factor for the outcome after surgery were limited (n = 42). The studies reported 154 different outcomes. The most commonly reported outcomes after rTKA were: re-revision (155 times), readmission (88 times), and reinfection (85 times). Only five studies included costs as outcome. Outcomes and prognostic factors that are routinely registered as part of clinical practice (e.g. BMI, sex, complications) or in (inter)national registries are studied frequently. Studies on prognostic factors, such as functional and sociodemographic status, and outcomes as healthcare costs, cognitive and mental function, and psychosocial impact are scarce, while they have been shown to be important for patients with osteoarthritis.

Bone Hook Reduction Technique Combined with Lateral Parapatellar Arthrotomy for Periprosthetic Distal Femoral Fractures Following Total Knee Arthroplasty: A Technical Note

OBJECTIVE

To report a bone hook reduction technique combined with lateral parapatellar arthrotomy for periprosthetic distal femoral fractures following total knee arthroplasty (TKA).

METHODS

From April 2012 to June 2018, a total of 31 knees who underwent this technique for the treatment of periprosthetic distal femoral fractures following TKA were retrospectively reviewed. Through a lateral parapatellar arthrotomy, the vastus lateralis fascia was dissected from the muscle belly to allow anteromedial mobilization of the muscles. With direct visualization of the posteriorly angulated distal fragment, a bone hook was placed on the anterior flange of the femoral component. The hook was then elevated to correct the posteriorly angulated and shortened distal fragment. The coronal and sagittal alignments of the distal segment with the femoral shaft were confirmed using fluoroscopic images, and internal fixation was performed using an anatomically pre-contoured lateral locked plate. Once the overall length and sagittal plane alignment were restored, the plate was inserted via the previous articular approach. The plate was centered on the femur using anteroposterior and lateral fluoroscopy and then fixed.

RESULTS

A total of 28 patients underwent internal fixation using the bone hook reduction technique combined with lateral parapatellar arthrotomy for the treatment of periprosthetic distal femoral fractures following TKA. The average age at operation was 70.9 years (range, 62-83 years), and the average follow-up period was 17.5 months (range, 12-48.5 months). Fractures were classified as Su type I (13/28 [46.4%]), type II (11/28 [39.3%]), and type III (4/28 [14.3%]). Bone union was confirmed radiographically in all patients.

CONCLUSION

The bone hook reduction technique is a simple and effective method to reduce the distal fragment in periprosthetic distal femoral fractures following TKA.

A novel open synovectomy technique using an arthroscopy shaver blade in revision surgery to treat infected total knee arthroplasty: a technical note

Background

This article introduces a novel open synovectomy technique using an arthroscopy shaver blade to effectively remove intra-articular synovitis during revision surgery for infected primary total knee arthroplasty.

Methods (techniques)

Open synovectomy is performed using a 4.2-mm arthroscopy shaver blade, and the handpiece is connected to suction drainage. Suction is supplied through the central cylinder of the shaver blade to bring the debrided fragments of soft tissue into the window. Grossly inflamed, reddened, diseased synovium is debrided to reveal yellowish, healthy synovium. The inflamed tissues of the knee joint (suprapatellar pouch, medial and lateral gutters, and peripatellar area) are debrided. Then, with maintaining full flexion of the knee joint, a shaver equipped with a longer bar can be used to easily access the medial and lateral posterior compartments, which are generally difficult to access.

Results

During a mean of 13.5-month follow-up, there was no recurrent infection in either group; however, patients who underwent the novel technique improved significantly faster in terms of acute serological markers during the first period.

Conclusions

This technique yielded favorable outcomes compared with the conventional technique. In particular, it may facilitate the approach to the posterior joint space, which is difficult to access.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03024-5.