Is bilateral total knee arthroplasty staged at a one-week interval safe? A matched case control study

No differences in terms of complications, readmissions, reoperations, and patient-reported outcomes in simultaneous bilateral versus staged bilateral total knee arthroplasty in selected patients

BACKGROUND

The safety and the clinical success of simultaneous bilateral total knee arthroplasty (BTKA) is controversial. The aim of this study was to compare complications and patient-reported outcomes following simultaneous BTKA (simBTKA) versus staged BKTA (staBTKA) in patients affected by bilateral symptomatic end-stage knee osteoarthritis (OA).

METHODS

Data from patients who underwent simBTKA or staBTKA at a single institution from January 2017 to December 2020, with a minimum 1-year follow up period were retrospectively collected. Differences in terms of complications and clinical success were compared among the simBTKA and staBTKA patient groups. Alpha was set at 0.05.

RESULTS

A total of 173 patients were included in this study. The results revealed no statistically significant differences between the two groups in terms of mortality, revision rate, readmission rate, local and systemic complications and patient-reported outcomes. SimBTKA group had a shorter operating room time (96 (73-119) vs. 195 (159-227); P < 0.0001), and length of hospital stay (4 (3-5) vs. 7 (6-9); P < 0.0001) compared with the staBTKA group.

CONCLUSIONS

SimBTKA performed in a selected patient population at a high-volume center can be considered comparable to staBTKA in terms of safety, postoperative complications, 30-day readmissions and patient satisfaction. Consequently, reduced operating room time and hospital stay renders simBTKA a cost-effective and advantageous option, not only for patients, but also for healthcare institutes. Furthermore, the current study also highlights the importance of correct patient selection based on clinical preoperative characteristics.

Incidence of Postoperative Infection Following Simultaneous Bilateral Knee Arthroplasty: A Systematic Review and Meta-Analysis

Total knee arthroplasty is one of the most common orthopedic procedures. Simultaneous bilateral knee arthroplasty involves performing total knee arthroplasty on both knees in a single anesthetic session. This systematic review and meta-analysis followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. A primary search was performed using PubMed, EBSCO, Scopus, Web of Science, Clarivate, and Google Scholar databases. Quantitative data synthesis was performed using MedCalc® Statistical Software version 20.115 to determine the pooled prevalence of the infection among patients who underwent simultaneous bilateral knee arthroplasty. The Newcastle-Ottawa Scale was used to assess study quality. We included 30 studies in our quantitative data synthesis, with a total population of 118,502 patients (237,004 knees). The pooled prevalence of superficial infection, deep infection, and unspecified surgical site infection was estimated to be 0.86% (95% confidence interval: 0.62-1.13%), 0.84% (95% confidence interval: 0.64-1.05%), and 1.18% (95% confidence interval: 0.45-2.27%), respectively. There was significant heterogeneity (I2 >50%) in all analyses, and inspection of funnel plots revealed a symmetrical distribution of plotted data. We found that the infection rates following simultaneous bilateral knee arthroplasty were relatively low but heterogeneous, as the data showed marked variability. Superficial infections were more common than deep infections; however, there was a small difference in their prevalence. Furthermore, the reliability of our findings was limited owing to significant heterogeneity.

Use of Grafts on an Open Gap Is Advantageous for Preventing Correction Loss in 1-Week Staged Bilateral Open-Wedge High Tibial Osteotomies

One-week staged bilateral open-wedge high tibial osteotomies (OWHTOs) can be a safe procedure, with the added advantage of fast functional recovery, cost saving, and reduced hospital stay. However, there can be concerns about correction loss after 1-week staged OWHTOs because high loading is inevitably applied to osteotomy sites during postoperative weight bearing. Although leaving the osteotomy site with no grafts is possible in OWHTOs, the use of grafts can provide additional stability to the osteotomy site and prevent correction loss. We compared the amount and incidence of correction loss between 1-week staged bilateral OWHTOs with and without allogenic bone grafts. Seventy-five patients who underwent 1-week staged bilateral OWHTOs with a locking spacer plate (Nowmedipia, Seoul, Korea) by a single surgeon were retrospectively reviewed. Allogenic cancellous bone grafts were applied in 53 patients (group G; 106 knees, operated consecutively between 2012 and 2017) but not in 22 patients (group N; 44 knees, operated consecutively between 2017 and 2019). Demographics were similar between the groups. Radiographically, the mechanical axis (MA), medial proximal tibial angle (MPTA), and posterior tibial slope (PTS) were evaluated preoperatively and within 1 year postoperatively. Unstable hinge fracture was investigated using computed tomography in all cases. The incidence of correction loss (MPTA loss ≥ 3 degrees) was determined. There were no significant differences in the MA, MPTA, and PTS between the groups preoperatively and 2 weeks postoperatively. The incidence of unstable hinge fractures did not differ. The losses in MA, MPTA, and PTS during the first postoperative year were significantly greater in group N than in group G (MA, -5.5 vs. -2.3 degrees; MPTA, -3.0 vs. 0 degrees; PTS, -2.0 vs. -0.7 degrees; p < 0.05 on all parameters). The correction loss incidence was 6.6% (7/106) and 31.8% (14/44) in groups G and N, respectively (p < 0.001). Appropriate treatment is necessary to prevent correction loss in 1-week staged bilateral OWHTOs. Grafting, which provides additional stability to the osteotomy site, is a recommended method. Level of evidence is IV.

Mortality Following Simultaneous Versus Staged Bilateral Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

Bilateral total knee arthroplasty (BTKA) is a common intervention for bilateral knee osteoarthritis, and the choice between simultaneous (SimBTKA) and staged (StaBTKA) procedures remains a critical decision. This meta-analysis systematically reviews and analyzes the existing literature to compare mortality outcomes associated with SimBTKA and StaBTKA. A comprehensive search was conducted across major databases for studies reporting mortality outcomes in SimBTKA and StaBTKA. Inclusion criteria encompassed studies published up to the cutoff date of January 2023, and a total of 37 studies were included in the quantitative synthesis. Meta-analysis was performed using a random-effects model to calculate odds ratios (ORs) with 95% confidence intervals (CIs) using the Review Manage 5.4 software. The meta-analysis included 86,333 SimBTKA cases and 115,146 StaBTKA cases. The overall mortality rate in SimBTKA was 0.66%, while StaBTKA's was 0.43%. The pooled OR for mortality in SimBTKA versus StaBTKA was 1.55 [1.16, 2.08], indicating a statistically significant higher mortality risk in SimBTKA. Our findings suggest that SimBTKA is associated with an increased risk of mortality compared to StaBTKA. This meta-analysis provides valuable insights into the comparative mortality outcomes of SimBTKA and StaBTKA. While SimBTKA may offer potential advantages, including a single anesthesia event and shorter recovery time, clinicians should consider the increased mortality risk associated with this approach. Future research should focus on prospective studies with standardized reporting to further elucidate the nuanced factors influencing mortality outcomes in bilateral knee arthroplasty.

No Difference in Perioperative Complications for Bilateral Total Knee Arthroplasty Staged at 1 Week Compared With Delayed Staging

INTRODUCTION

Controversy exists regarding the safety of simultaneous bilateral total knee arthroplasty (TKA) versus two TKA procedures staged months apart in patients with bilateral knee arthritis. Here, we investigated a third option: bilateral TKA staged 1 week apart. In this study, we examined the rate of complications in patients undergoing bilateral TKA staged at 1 week compared with longer time intervals.

METHODS

A retrospective review of 351 consecutive patients undergoing bilateral TKA at our institution was conducted. Patients underwent a 1-week staged bilateral procedure with planned interim transfer to a subacute rehabilitation facility (short-staged) or two separate unilateral TKA procedures within 1 year (long-staged). Binary logistic regression was used to compare outcomes while controlling for year of surgery, patient age, body mass index, and Charlson Comorbidity Index.

RESULTS

Two hundred four short-staged and 147 long-staged bilateral TKA patients were included. The average interval between procedures in long-staged patients was 200.9 ± 95.9 days. Patients undergoing short-staged TKA had a higher Charlson Comorbidity Index (3.0 ± 1.5 versus 2.6 ± 1.5, P = 0.017) with no difference in preoperative hemoglobin ( P = 0.285) or body mass index ( P = 0.486). Regression analysis demonstrated that short-staged patients had a higher likelihood of requiring a blood transfusion (odds ratio 4.015, P = 0.005) but were less likely to return to the emergency department within 90 days (odds ratio 0.247, P = 0.001). No difference was observed in short-term complications ( P = 0.100), 90-day readmissions ( P = 0.250), or 1-year complications ( P = 0.418) between the groups.

CONCLUSION

Bilateral TKA staged at a 1-week interval is safe with a comparable complication rate with delayed staged TKA, but allows for a faster total recovery time.

LEVEL OF EVIDENCE

Level III.

A nationwide comparison of staggered and simultaneous bilateral knee arthroplasty during a single hospitalization: Trends, risks and benefits

Background

We aimed to: (1) perform a nationwide trend analysis of staggered and simultaneous bilateral knee arthroplasty (KA); (2) investigate patient demographics and hospital characteristics in two groups; and (3) compare the outcomes of two groups with a focus on complications, length of stay (LOS) and hospitalization costs.

Methods

Utilizing the Hospital Quality Monitoring System, we included patients who underwent bilateral KA during a single hospitalization between 2013 and 2019. Patient demographics and hospital characteristics were compared between two groups. Outcomes were compared between propensity-score matched groups using logistic and linear regression.

Results

During the study period, 6291 staggered bilateral KA and 6284 simultaneous bilateral KA were performed. From 2013 to 2019, the proportion of staggered bilateral KA increased from 32.74% to 59.08%. Patients who were older, were single, had more comorbidities and had a non-osteoarthritis indication for surgery tended to receive staggered bilateral KA. Compared with 3327 propensity-score matched patients undergoing simultaneous bilateral KA, patients undergoing staggered bilateral KA were associated with a significantly lower incidence of wound infection (odds ratio [OR] ​= ​0.22; 95% confidence interval [CI], 0.07–0.65), and readmission within 30 days (OR ​= ​0.73; 95%CI, 0.54–0.99) and 90 days (OR ​= ​0.70; 95%CI, 0.55–0.89). However, staggered bilateral KA had higher odds of blood transfusion (OR ​= ​1.20; 95%CI, 1.02–1.40) and deep venous thrombosis (DVT) (OR ​= ​2.62; 95%CI, 1.82–3.98). Moreover, staggered bilateral KA can lead to higher costs (108,316.21 Chinese yuan [CNY] vs 103,367.60 CNY) and longer LOS (17.29 days vs 12.18 days) than simultaneous bilateral KA.

Conclusion

Our study indicates that staggered bilateral KA has become more common than simultaneous bilateral KA in China. Compared to simultaneous bilateral KA, staggered bilateral KA was associated with a lower incidence of wound infection and readmission. Staggered bilateral KA may be an alternative for patients who can't tolerate simultaneous surgery.

The translational potential of this article: Our study indicates that staggered bilateral KA is a safe and economical option for elderly patients who require bilateral KA but are at high clinical risk. The rising proportion of staggered bilateral KA will be a new trend in bilateral KA.

Age-adjusted Charlson comorbidity index as a novel guideline for patient selection between unilateral versus bilateral simultaneous total knee arthroplasty

PURPOSE

The aim of this study was to validate the age-adjusted Charlson comorbidity index as a clinical practice guideline for patient selection between unilateral total knee arthroplasty (UTKA) and bilateral simultaneous total knee arthroplasty (BSTKA).

METHODS

A consecutive series of 1016 patients undergoing UTKA (402 patients) or BSTKA (614 patients) was analysed. The age-adjusted Charlson comorbidity index (ACCI) was measured for all the patients and graded as low (0-2 score), moderate (3-4 score) and high risk (≥ 5 score). The complications occurring within 3 months of surgery were compared between UTKA and BSTKA recipients.

RESULTS

Following surgery, the complication rate was comparable between both the groups. However, among high-risk patients, there was significant difference in the complication rates between UTKA and BSTKA groups (12% versus 30.76%, minor; 8% versus 23.07%, major complication). The high-risk patients who had bilateral surgery were at more than three times greater risk of developing major and minor complications than those who had unilateral surgery.

CONCLUSION

The BSTKA procedure is associated with significantly higher risk of post-operative complications than UTKA procedure in patients with ≥ 5 ACCI scores.

The BTK Safety Score: A Novel Scoring System for Risk Stratifying Patients Undergoing Simultaneous Bilateral Total Knee Arthroplasty

Selection of appropriate candidates for simultaneous bilateral total knee arthroplasty (si-BTKA) is crucial for minimizing postoperative complications. The aim of this study was to develop a scoring system for identifying patients who may be appropriate for si-BTKA. Patients who underwent si-BTKA were identified in the National Surgical Quality Improvement Program database. Patients who experienced a major 30-day complication were identified as high-risk patients for si-BTKA who potentially would have benefitted from staged bilateral total knee arthroplasty. Major complications included deep wound infection, pneumonia, renal insufficiency or failure, cerebrovascular accident, cardiac arrest, myocardial infarction, pulmonary embolism, sepsis, or death. The predictive model was trained using randomly split 70% of the dataset and validated on the remaining 30%. The scoring system was compared against the American Society of Anesthesiologists (ASA) score, the Charlson Comorbidity Index (CCI), and legacy risk-stratification measures, using area under the curve (AUC) statistic. Total 4,630 patients undergoing si-BTKA were included in our cohort. In our model, patients are assigned points based on the following risk factors: +1 for age ≥ 75, +2 for age ≥ 82, +1 for body mass index (BMI) ≥ 34, +2 for BMI ≥ 42, +1 for hypertension requiring medication, +1 for pulmonary disease (chronic obstructive pulmonary disease or dyspnea), and +3 for end-stage renal disease. The scoring system exhibited an AUC of 0.816, which was significantly higher than the AUC of ASA (0.545; p < 0.001) and CCI (0.599; p < 0.001). The BTK Safety Score developed and validated in our study can be used by surgeons and perioperative teams to risk stratify patients undergoing si-BTKA. Future work is needed to assess this scoring system's ability to predict long-term functional outcomes.

Short Interval Staged Bilateral Total Knee Arthroplasty: Safety Compared to Simultaneous and Later Staged Bilateral Total Knee Arthroplasty

BACKGROUND

Simultaneous bilateral total knee arthroplasty (sim-BTKA) is reported to be safe in a select group of patients. Patients with symptomatic bilateral knee arthritis who are not candidates for sim-BTKA require staged surgery (stag-BTKA). This study aimed to compare the safety and complications associated with sim-BTKA with stag-BTKA performed at 2 time intervals.

METHODS

This retrospective study of prospectively collected data includes bilateral TKA cases performed between 2001 and 2019. A cohort of sim-BTKA (n = 2728) was compared to a cohort of stag-BTKA (n = 1658). The staged group was subdivided according to the interval between surgeries: ≤90 days (early) and ≥91 days (later). Multivariate logistic regression analyses were used to adjust for confounding variables.

RESULTS

In-hospital complication rates were lower in both arms of the stag-BTKA groups vs the sim-BTKA. The sim-BTKA group had higher odds ratio of anemia, electrolyte disturbances, pulmonary embolism, and respiratory, urinary, gastrointestinal, and neurological complications. Lower rates of all-cause revision were found in stag-BTKA vs sim-BTKA groups. There was a trend toward revision due to deep infection when increasing the interim before the second stag-BTKA procedure. No differences in complication rates after the second surgery were detected between the early and later stag-BTKA.

CONCLUSION

This study demonstrates that sim-BTKA is associated with more complications and revisions when compared to stag-BTKA. Performing the second-stage TKA at 90 days or less after the first TKA is not associated with increased risk of complications. Performing sim-BTKA, simply for convenience, is not warranted and should be reserved for a select group of patient matching specific criteria.

Comparison of the Effect and Complications of Sequential Bilateral Arthroplasty at Different Time Intervals and Simultaneous Bilateral Total Knee Arthroplasty: A Single-Centre Retrospective Cohort Study

INTRODUCTION

To the authors' knowledge, there is no current consensus regarding the optimal interprocedural interval for patients who have undergone bilateral total knee arthroplasty (BTKA). The purpose of this study is to evaluate complication rates and functional outcome in patients who have undergone BTKA (simultaneous or sequential at different time intervals), and to determine an optimal time frame for the second knee.

METHODS

Data from 315 patients who were able to tolerate simultaneous BTKA according to the anaesthesiologist's preoperative assessment between 2016 and 2020 were analysed retrospectively. According to the operative time interval, they were divided into simultaneous, ≤ 1-month sequential, 1- to 3-month sequential, and ≥ 3-month sequential BTKA groups. The primary outcomes were revision and readmission rates during the follow-up period, and the secondary outcomes were hospital length of stay (LOS), transfusion and postoperative complications.

RESULTS

There was no difference in the implant survival or readmission rate between the groups (p > 0.05). Multivariable linear regression showed that interprocedural interval and body mass index (BMI) affected LOS; the LOS of simultaneous BTKA was the shortest (p < 0.05). BMI was associated with an increased LOS of 0.25 days (95% CI 0.02-0.48, p = 0.03). A modified Poisson regression model showed that the odds of blood transfusion were reduced in sequential BTKAs of any interval (p < 0.05), and preoperative haemoglobin (Hb) was also a risk factor (RR 0.96, 95% CI 0.95-0.98, p < 0.001). The interprocedural interval was not a risk factor for postoperative cardiovascular and cerebrovascular complications.

CONCLUSION

For appropriate patients, simultaneous BTKA is beneficial. However, higher preoperative haemoglobin was required to mitigate the high blood transfusion rate associated with simultaneous surgeries. If suitable patients refuse simultaneous BTKA for other non-medical reasons, sequential BTKA with an interval greater than 1 month is recommended.

Comparison of functional outcome of simultaneous and staged bilateral total knee arthroplasty : systematic review of literature

Safety of simultaneous bilateral TKA (simBTKA) and staged BTKA (staBTKA) have been compared in previous systematic reviews but functional outcome remains neglected aspect of the debate. We performed a systematic review of contemporary literature to compare the functional outcome of simBTKA and staBTKA. We searched PubMed/MEDLINE, EMBASE and Cochrane Central Database to identify all articles published between 2000 and July 2020 that evaluated the outcome of patients undergoing BTKA either in simultaneous or staged manner. Ten articles were identified which met the inclusion criteria. Functional outcome was reported in terms of Knee Society score (KSS), range of motion (ROM), Oxford Knee Score (OKS) and Western Ontario and McMaster University score (WOMAC) in seven, five, four and two studies respectively. KSS gained on average 66.6 points (47.5-95.3) for simBTKA and 65.1 points (44.4-97.2) for staBTKA without significant difference between two groups. There was no difference in post-operative ROM (maximum post-operative flexion being 124.4 and 125.1 for simBTKA and staBTKA groups respectively). Mean improvement in OKS ranged from 20 to 32.6 for simBTKA and 21.6 to 33.1 for staBTKA. There was moderate evidence to suggest that both simultaneous BTKA and staged BTKA produce equivalent improvement in functional scores.

Simultaneous Bilateral Total Knee Arthroplasty Is Associated With Shorter Length of Stay but Increased Mortality Compared With Staged Bilateral Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

Primary total knee arthroplasty (TKA) is associated with high patient satisfaction. However, controversy remains regarding the safety and efficacy of conducting simultaneous bilateral (simBTKA) versus staged bilateral TKA (staBTKA). The objective of this systematic review and meta-analysis was to evaluate the current evidence for simBTKA versus staBTKA and compare clinical outcomes including mortality, complications and length of stay (LOS).

METHODS

A search was performed of PubMed, MEDLINE, EMBASE and Cochrane central databases between January 2000 and March 2020. Search terms included "simultaneous," "staged," and "bilateral TKA." Inclusion criteria comprised studies comparing outcomes of simBTKA versus staBTKA. Quality of included studies was assessed and meta-analyses of pooled data was conducted.

RESULTS

29 articles published between 2001 and 2020 were included in qualitative synthesis from 927 potentially relevant titles, comprising 257,284 patients. 104,207 patients underwent simBTKA and 153,632 patients underwent staBTKA. simBTKA was associated with significantly increased 90-day mortality rate (P < .00001, OR 2.24, 95% CI 1.79-2.81), increased incidence of pulmonary embolism (P < .00001, OR 1.69, 95% CI 1.51-1.89), venous thrombosis (P < .00001, OR 1.33, 95% CI 1.23-1.43), and neurological complications (P = .002, OR 1.42, 95% CI 1.13-1.77). Incidence of superficial and deep infection was significantly increased with staBTKA (P = .02, P < .00001 respectively). Revision rate within one year was equivocal. Mean LOS was 2.1 days shorter for simBTKA.

CONCLUSION

SimBTKA was associated with decreased incidence of infection and LOS but increased incidence of 90-day mortality, venous thromboembolism and neurological complications. Revision rates were equivocal. Patients should be selected and counseled based on the risks respective to each strategy.

Staggered bilateral total knee arthroplasty during a single hospitalization: is it still an option? a systematic review

BACKGROUND

Bilateral knee osteoarthritis requiring total knee arthroplasty (TKA) can be addressed simultaneously in one surgical setting, staggered a few days apart during a single hospitalization, or staged several weeks to months apart. Several studies have reported on the complications and clinical outcomes of staggered bilateral TKA (BTKA) in a single hospitalization. However, there is no consensus regarding the safety and efficacy of this practice.

MATERIALS AND METHODS

We performed a systematic review of the literature, utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and identifying articles that reported the clinical outcomes and postoperative complications following staggered BTKA.

RESULTS

Overall, six articles were included for analysis, including 43,892 patients in total. Females (n = 25,931; 59% of all patients) outnumbered males (n = 17,961; 40.1% of all patients), and most patients were middle-aged or elderly (mean age: 68.0 years). The majority of studies (83%) used a 1-week interval as the maximum time for single-hospitalization staggered BTKA. Five studies (83%) reported no difference in mortality rates between staggered, simultaneous, or staged BTKA. Compared to staged BTKA, staggered BTKA conferred an increased rate of blood transfusions. There was no consensus that staggered BTKA led to reduced complications rates, compared to simultaneous or staged BTKA.

CONCLUSIONS

Single-hospitalization staggered BTKA does not appear to be safer than the well-established simultaneous or staged procedures. Overall, the data suggest that staggered BTKA will continue to decline in utilization, as staggered BTKA does not appear to yield clinical advantage over simultaneous BTKA in a medically appropriate patient. LEVEL OF EVIDENCE III: systematic review (lowest level of studies included).

Cost analysis of staged versus simultaneous bilateral total knee and hip arthroplasty using a propensity score matching

BACKGROUND

Total joint arthroplasty (TJA), including total knee arthroplasty (TKA) and total hip arthroplasty (THA), is required for many patients. This study aimed to evaluate the medical costs, length of stay (LOS), blood transfusion and in-hospital complications in patients undergoing simultaneous and staged TJA.

METHODS

All patients who underwent primary bilateral TJA from 2013 to 2018 in our institute were included. The propensity score matching analysis was performed between simultaneous and staged TJA patients. The difference in medical costs, LOS, blood transfusion and in-hospital complications was compared between simultaneous and staged groups.

RESULTS

Except for materials fees and general therapy fees, medical costs (bed fees, general therapy fees, nursing care fees, check-up and laboratory test fees, surgical fees and drug fees) were significantly lower in the simultaneous TKA, THA and TJA group. The total average medical costs in simultaneous and staged TKA groups were $15 385 and $16 729 (p<0.001), respectively; THA groups were $14 503 and $16 142 (p=0.016), respectively; TJA groups were $15 389 and $16 830 (p<0.001), respectively. The highest and lowest costs were materials fees and nursing care fees. No significant differences were found for five common comorbidities and postoperative complications between the two subgroups. The simultaneous groups had a shorter LOS and the differences from the staged group for TKA, THA and the TJA group were 8, 6 and 8 days, respectively. The incidence of blood transfusion is higher for simultaneous groups and the difference from the staged group for TKA, THA and TJA is 32.69%, 18% and 29.3%, respectively.

CONCLUSIONS

Our results indicate that simultaneous TKA and THA with a shorter LOS would cost fewer (costs incurred during hospitalisation) than staged TKA and THA. Complication rates were not affected by the choice for staged or simultaneous arthroplasty, but the incidence of blood transfusion was higher in the simultaneous groups.

Does the Timing of the Second Surgery of a Staged Bilateral Total Joint Arthroplasty Affect the Rate of Hospital Adverse Events and Perioperative Outcomes?

BACKGROUND

The optimal timing of the second surgery in primary staged bilateral total hip/knee arthroplasty remains uncertain. Perioperative hospital adverse events represent a significant issue, even "minor events" lead to substantial costs in workup tests, interconsultations, and/or increased hospital length-of-stay (LOS). Therefore, we sought to ascertain whether the timing of the second arthroplasty affects perioperative outcomes and/or rates of adverse events.

METHODS

We retrospectively reviewed a consecutive series of 670 primary staged bilateral total hip/knee arthroplasty performed by 2 surgeons (2010-2016) at a single institution. The days between both arthroplasties were calculated for each pair of hips or knees. We evaluated demographics and LOS, discharge disposition, adverse events (ie, nausea, pulmonary embolism), and transfusion rates. The second arthroplasties (n = 335) were set apart in 2 groups based on the time they were done with respect to their corresponding contralateral first arthroplasty using 3 different thresholds: (1) ≤90 vs >90 days, (2) ≤180 vs >180 days, and (3) ≤365 vs >365 days.

RESULTS

No significant differences in outcome comparisons were observed using either 90 or 180 days thresholds. However, using the 365 days thresholds, the mean LOS (2.21 vs 1.92 days, P = .015), adverse event (26% vs 15.3%, P = .021), total transfusion (7.4% vs 1.5%, P = .020), and allogeneic transfusion (6.9% vs 1.5%, P = .033) rates were significantly higher in second arthroplasties performed at or less than 1 year apart from the first, respectively.

CONCLUSION

Staging the second arthroplasty more than a year apart from the first one seems to offer better LOS and rates of hospital adverse events, transfusions. However, unless patients are willing to wait a year between surgeries, our data also suggest no increased risk in regards to adverse events when proceeding before or after 90/180 days.

LEVEL OF EVIDENCE

Level III.

Unilateral versus bilateral total knee arthroplasty: A registry study on survival and risk factors

BACKGROUND

Bilateral cases, representing at least 25% of total knee arthroplasties (TKA), could convey a statistical bias linked to dependency. Registries allow exploring this issue, susceptible to question surgeon validated protocols. Do bilateral total knee arthroplasties behave differently than unilateral knees in terms of implant survival?

HYPOTHESIS

Bilateral TKA have a better survival than unilateral TKA.

PATIENTS AND METHODS

A number of 14,652 bilateral and 27,440 unilateral TKAs were compared. Influencing factors were tested with hazard ratios applied on bilateral knees.

RESULTS

Bilateral knees had a better survival (p<0.001). Delay between first and second side surgeries had an influence on survival of the first knee: if below a year, the first knee survival was superior to the second knee; more than three years between both arthroplasties significantly decreased the survival of the first implant. If the first knee was revised, the hazard ratio for revision of the second implant was 3.5.

DISCUSSION

Series should include separate evaluations of bilateral cases, because they have a better survival than unilateral knees. A long delay between both knee replacements could impact both implant survivals. Level of Evidence III, Cohort Comparative Study.

Bilateral total knee arthroplasty: Simultaneous or staged? A systematic review and meta-analysis

BACKGROUND

Total knee arthroplasty (TKA) is one of the most successful orthopedic surgeries performed in recent decades. However, controversies still exist between conducting simultaneous or staged bilateral TKA. The objective of this study is to conduct a systematic review assessing the clinical outcome associated with simultaneous bilateral and staged bilateral total knee arthroplasty (BTKA).

METHODS

A search was applied to CNKI, Embase, Medline, and Cochrane central database (January 2000-July 2018). All studies that compared simultaneous bilateral TKA (simBTKA) with staged bilateral TKA (staBTKA) without language restriction were reviewed, and qualities of included studies were assessed using the Newcastle-Ottawa Scale. Data were pooled and a meta-analysis completed.

RESULTS

The 18 studies were identified to be eligible. The 18 comparative studies published from 2001 to 2018, covered 73617 participants in the simBTKA group and 61838 in the staBTKA group, respectively. Results of meta-analyses indicated that simBTKA showed a lower risk of deep infection and respiratory complications, but increased mortality, pulmonary embolism (PE), and deep-vein thrombosis (DVT) compared with staBTKA. There were no significant differences in revision, superficial infection, arthrofibrosis, cardiac complications, neurological complications and urinary complications between procedures.

CONCLUSIONS

Since there are risks and benefits to both procedures, these potential complications must be interpreted in light of each individual patient's needs and concerns. Further research must be conducted, in the form of a randomized clinical trial, to evaluate the outcomes mentioned in this review.

Comparing the 30-Day Risk of Venous Thromboembolism and Bleeding in Simultaneous Bilateral vs Unilateral Total Knee Arthroplasty

BACKGROUND

Simultaneous bilateral total knee arthroplasty (SBTKA) may offer certain benefits; however, its overall safety is still disputed. This study aimed at comparing the risk of thromboembolism and bleeding in patients who underwent SBTKA vs unilateral total knee arthroplasty (TKA).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database from 2008 to 2015 was used to investigate the short-term postoperative complications and their risk factors following SBTKA as compared to unilateral TKA. Demographics, comorbidities, and 30-day outcomes were analyzed. Complications with an increased incidence following SBTKA were stratified to identify subgroups of patients at high risk.

RESULTS

A total of 155,022 patients were identified, of which 150,581 underwent unilateral TKA and 4441 underwent SBTKA. The SBTKA group was found to be at a higher risk of venous thromboembolism (VTE), bleeding, and composite morbidity. Stratification analysis revealed that SBTKA subgroups at higher risk of VTE include patients of black or Asian origin, obese patients, and those who underwent anesthesia other than general or spinal/epidural. SBTKA subgroups at higher risk of bleeding include patients older than 85 years, those with race other than white, underweight and obese patients, and patients who underwent anesthesia other than spinal/epidural. Although none of the subgroups were protected from bleeding, patients who underwent spinal/epidural anesthesia had a lower risk of bleeding compared to other types of anesthesia.

CONCLUSION

SBTKA confers an increased risk of postoperative VTE, bleeding, and composite morbidity at 30 days, with no increase in mortality.

Staggered Rather Than Staged or Simultaneous Surgical Strategy May Reduce the Risk of Acute Kidney Injury in Patients Undergoing Bilateral TKA

BACKGROUND

The strategy for bilateral total knee arthroplasty (TKA) depends on the timing of surgery for each knee. The purpose of this study was to determine whether the type of surgical strategy for bilateral TKA (staggered, staged, or simultaneous) influences the incidence of acute kidney injury (AKI) and related complications.

METHODS

Enrolled patients from a single tertiary teaching hospital were divided into 3 groups according to the surgical strategy for bilateral TKA: staggered (≤7 days between the first and second procedure; n = 368), staged (8 days to 1 year between the first and second procedure; n = 265), or simultaneous (n = 820). The incidence of AKI as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria was assessed. The rates of major postoperative complications, major adverse cardiovascular and cerebral events, intensive care unit (ICU) admissions, and mortality were also evaluated. To reduce the influence of possible confounding factors, inverse probability of treatment weighting based on propensity-score analysis was used.

RESULTS

The primary outcome was the incidence of AKI according to surgical strategy. The staggered group had a lower rate of AKI compared with the other 2 groups (p < 0.001): 2.4% (9 of 368 patients), 6.0% (16 of 265), and 11.2% (92 of 820) in the staggered, staged, and simultaneous groups, respectively.

CONCLUSIONS

The type of bilateral TKA strategy was an independent risk factor for the development of AKI. The assessment of additional risk factors for the development of AKI is essential before deciding on surgical strategy.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

No difference in the functional improvements between unilateral and bilateral total knee replacements

Background

Differences between staged bilateral total knee replacement (TKR) and simultaneous bilateral TKR have been investigated, but few studies have investigated differences in the functional improvements resulting from these methods. Therefore, this study investigates the different functional improvements between staged bilateral total knee TKR and simultaneous bilateral TKR.

Methods

Among 144 potential bilateral TKR patients who were included in this study, 93 (64.6%) patients selected unilateral TKR and 51 (35.4%) selected bilateral TKR. Functional improvements were assessed using the Western Ontario and McMaster University osteoarthritis index (WOMAC) and the Medical Outcomes Trust Short Form-36 (SF-36), and patients were interviewed pre-operatively and after 6 months. A generalized equation was used to test for differences in functional improvements.

Results

After TKR, pain, stiffness, function and total WOMAC scores were significantly reduced in both groups, with mean changes from − 26.6 to − 41.4 and from − 27.5 to − 42.2.The mean health change of SF-36 scores, physical component and mental component scores changed to 45.2 ± 18.2, 74.0 ± 15.4 and 77.0 ± 9.6, respectively, in Group 1 and 47.1 ± 17.1, 74.0 ± 15.2 and 75.5 ± 12.1, respectively, in Group 2.

Unilateral and simultaneous bilateral TKR produce similar functional improvements, although current work status may be a novel impact factor.

Conclusion

No differences in functional improvements were identified between patients who selected unilateral versus bilateral TKR, indicating no recommendation for one procedure over the other.

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2006-x) contains supplementary material, which is available to authorized users.

Comparison of the outcome between unilateral and bilateral open wedge high tibial osteotomy in the bilateral varus knees

INTRODUCTION

Bilateral open wedge high tibial osteotomy (OWHTO) can be performed in a staged manner to enable the healing and rehabilitation of each limb separately after surgery. However, the effects of staged bilateral OWHTO on the pattern of recovery and changes over time for each limb have not been established. Additionally, there is a lack of information regarding the optimal timing for staged surgery.

METHODS

Twenty-two patients (44 knees) in the bilateral OWHTO group and 42 patients (42 knees) in the unilateral OWHTO group were analyzed. Clinical and radiological results were evaluated and compared between the two groups. For the alignment change assessment, the hip-knee-ankle (HKA) angle and weight-bearing line (WBL) ratio were measured preoperatively and at postoperative 6 weeks, 3 months, 6 months, and 1 year.

RESULTS

The correction loss of HKA angle in the bilateral OWHTO group was significantly larger than that in the unilateral OWHTO group (0.5° ± 1.4° vs 1.3° ± 2.0°, p = 0.049). The correction loss of WBL ratio was significantly greater in the patients with staged bilateral OWHTO within a 3-month interval compared to those with staged bilateral OWHTO in an interval longer than 3 months (WBL ratio; 7.5% vs 2.1%, p = 0.01). There was no significant difference in the clinical scores and range of motion at the last follow-up.

CONCLUSION

The smaller loss of correction in the unilateral OWHTO group occurred compared to the bilateral OWHTO group. Additionally, surgeons should keep in mind that the amount of correction loss may be greater if staged bilateral OWHTO is performed at intervals of 3 months or less.

Simultaneous bilateral total knee arthroplasty in patients with end-stage hemophilic arthropathy: a mean follow-up of 6 years

To investigate the safety, cost-effectiveness, and clinical outcomes of simultaneous bilateral total knee arthroplasty (TKA) in hemophilic arthropathy (HA), the requirements for transfusions, complications, costs, hospital stays, Hospital for Special Surgery (HSS) knee scores, knee range of motion (ROM) and revision rates were compared between simultaneous bilateral and unilateral TKA in HA patients. A total of 36 patients and 54 knees were included. Compared to the unilateral group, the bilateral group did not require more transfusions (2.39 ± 3.13 vs 0.83 ± 1.38 units of RBCs, p > 0.05) or consumption of coagulation factors (50091.67 ± 25168.5 vs 46477.78 ± 11348.32 IU, p > 0.05), complications rate (13/36 vs 6/18, p > 0.05), hospital stay (32.39 ± 19.77 vs 29.11 ± 12.67 days, p > 0.05), or costs excluding prostheses (14945.41 ± 6634.35 vs 14742.12 ± 5746.78 US dollars, p > 0.05). Additionally, the two groups exhibited similar medium-term knee HSS scores (83.67 ± 7.11 vs 81.00 ± 10.35, p > 0.05) and ROM (89.39° ± 13.66° vs 88.91° ± 12.90°, p > 0.05). Our data indicate that bilateral TKA is a safe and cost-effective treatment for HA with similar medium-term results compared to unilateral TKA.