Bilateral simultaneous total knee arthroplasty

Bilateral Total Knee Arthroplasty: Current Concepts Review

»

Bilateral total knee arthroplasty (BTKA) is an effective surgical treatment for bilateral knee arthritis and can be performed as a simultaneous surgery under a single anesthetic setting or as staged surgeries on separate days.

»

Appropriate patient selection is important for simultaneous BTKA with several factors coming into consideration such as age, comorbidities, work status, and home support, among others.

»

While simultaneous BTKA is safe when performed on appropriately selected patients, current evidence suggests that the risk of complications after simultaneous BTKA remains higher than for staged BTKA.

»

When staged surgery is preferred, current evidence indicates that complication risks are minimized if the 2 knees are staged at least 3 months apart.

»

Simultaneous BTKA is the economically advantageous treatment option relative to staged BTKA, primarily because of shorter total operative time and total hospital stay.

Staging Bilateral Total Knee Arthroplasties Reduces Alignment Outliers

BACKGROUND

Patients frequently present with bilateral symptomatic knee osteoarthritis and request simultaneous total knee arthroplasties (TKAs). Technical differences between simultaneous and staged TKAs could affect clinical and radiographic outcomes. We hypothesized that staged TKAs would have fewer mechanical alignment outliers than simultaneous TKAs.

METHODS

We reviewed 87 simultaneous and 72 staged TKAs with at least 2 years of follow-up. Radiographic assessment was done using standing long leg and lateral radiographs of the knee. Coronal and sagittal measurements were performed by 4 blinded observers on 2 separate occasions with an intraobserver agreement of 0.95 and interobserver of 0.92.

RESULTS

The first simultaneous knee had no difference in the probability of establishing the mechanical axis outside 3° of neutral (45%) compared to the first staged knee (54%, P = .337). However, the second simultaneous knee (49%) was more likely to establish the axis outside mechanical neutral compared to the second staged knee (28%; odds ratio 2.54, confidence interval 1.31-4.94, P = .006). There was an increased risk of deep venous thrombosis with staged TKA (odds ratio 2.96, confidence interval 1.28-6.84, P = .011), but other perioperative complication rates were not significantly different. There were no clinically significant differences in range of motion or Knee Society Score.

CONCLUSION

There is a significantly increased risk of establishing the second knee outside mechanical neutral during a simultaneous TKA compared to staged bilateral TKAs, possibly related to a number of surgeon-related and system-related factors. The impact on clinical outcomes and radiographic loosening may become significant in long-term follow-up.

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.

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.

Simultaneous single-stage versus two-staged bilateral total knee arthroplasty: a prospective comparative study

PURPOSE

The study aims to prospectively compare peri-operative morbidity and mortality of simultaneous single-stage bilateral total knee arthroplasty (SS BLTKA) with two-staged bilateral total knee arthroplasty (TS BLTKA) performed within 12 months of the first surgery. We hypothesized that SS BLTKA is as safe as TS BLTKA.

METHODS

Patients with a minimum follow-up of 12 months were included in this study. Oxford knee score and quality of life index SF12 was compared between the 2 groups at six weeks and six month follow-up.

RESULTS

SS BLTKA included 250 patients and TS BLTKA included 210 patients. The minimum time interval between two operations was three weeks (mean 1.6 months, range 3 weeks-12 months). There was no significant difference between the 2 groups in peri-operative mortality, surgical site infection, major peri-operative complications. There was no difference between the 2 groups in the Oxford knee score and quality of life index SF12 at 6-month follow-up. There was no difference in the range of knee flexion between the 2 groups at six months. Post-operative haemoglobin drop was significantly more in SS BLTKA patients and consequently, blood transfusion requirement was significantly higher in SS BLTKA. There was a significantly higher length of hospital stay and duration of surgery in TS BLTKA group.

CONCLUSION

There does not appear to be a difference in complication rates between the 2 groups. SS BLTKA seems to be a logical choice if both knees have severe osteoarthritis. Patients with severe cardiopulmonary compromise were excluded, and a unilateral procedure may be preferred in them.

One-staged combined hip and knee arthroplasty: retrospective comparative study at mid-term follow-up

Background

To date, few knowledge is available about safety and effectiveness of one-staged combined hip and knee arthroplasty. The aim of our study was to evaluate, in a comparative fashion, complications and outcomes in patients who underwent one-staged hip and knee arthroplasty.

Methods

Forty-two patients were enrolled and allocated into two groups of 21 patients each: one-staged hip and knee arthroplasty (group A) and two-staged hip and knee arthroplasty (group B). The follow-up averaged 50.2 months. Postoperative complications and implant survivorship were assessed prospectively. Outcomes were evaluated with Harris Hip score (HSS), Western Ontario Mc-Ministry score for the hip (h-WOMAC), Knee Society score (KSS), and Western Ontario Mc-Ministry knee score (k-WOMAC). Hip and knee range of motion (ROM) were measured both preoperatively and at the last follow-up.

Results

Two (9.5%) patients in group A and three (14.3%) patients in group B developed complications (P = 0.8). Although a significant decrease in postoperative haemoglobin (Hgb) values was found in group A patients during the hospital stay, no differences in blood transfusions were found (P = 0.8). No significant differences were found comparing clinical-functional outcomes between the two groups, while a significant reduction of hospital length of stay was shown in group A patients.

Conclusions

One-staged combined hip and knee arthroplasty could be considered in patients with co-existing severe hip and knee osteoarthritis, providing similar complications and mid-term outcomes of two-staged procedures. However, the reproducibility safety and reliability of these procedures should be confirmed in prospective comparative randomised trials with more numerous patients.

Trial registration

Retrospectively registered

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.

Simultaneous, same-anaesthetic bilateral total knee arthroplasty has low mortality and complication rates

PURPOSE

The benefits of simultaneous bilateral total knee arthroplasty (SBTKR) include reduced hospital costs, single anaesthetic exposure and in many cases is also the patient's preference. Despite these potential benefits, risk-adversity with respect to assumed complications and mortality make it difficult for the orthopaedic surgeon and patient to make an informed decision. This study aimed to address the inconsistencies and lack of consensus in previous literature regarding the short-term complications and clinical safety of SBTKR in patients with end-stage knee osteoarthritis (OA).

METHODS

A cohort of 950 knees (475 patients) undergoing surgery between 2008 and 2013 was extracted from a prospectively collected clinical database and retrospectively linked to the Australian Joint Replacement Registry and hospital records. Patients underwent sequential SBTKR by their treating surgeon under one anaesthetic. Basic demographic data and outcome data including complications and mortality were collected. All data were analyzed using descriptive statistics only.

RESULTS

A total of 413 patients and 826 knees were included. The average age of the cohort was 70 years with range between 46 and 88 years. 50% of patients were female. The overall mortality rate during the study follow-up period was 1.9%, with an average time to death postoperatively of 23.8 months. There were no cases of acute postoperative mortality (< 6 weeks). Medical complication rates were low.

CONCLUSIONS

In contrast to the higher mortality and complication rates suggested in previous literature, this study has demonstrated that SBTKR is safe, with low mortality and complication rates under the current surgical protocol.

LEVEL OF EVIDENCE

IV.

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.

Cost Analysis, Complications, and Discharge Disposition Associated With Simultaneous vs Staged Bilateral Total Knee Arthroplasty

BACKGROUND

Simultaneous vs staged bilateral total knee arthroplasty (BTKA) has long been debated. The primary objective of this study was to compare actual hospital costs and complication rates in patients undergoing simultaneous BTKA (simBTKA) and staged BTKA (staBTKA) at a single institution.

METHODS

A total joint arthroplasty database from a single hospital was used to identify all patients who underwent primary BTKA from 2013 to 2016 and divided into simultaneous and staged groups. StaBTKA patients were included if both procedures were performed within 1 year by the same surgeon. The combined total hospital cost of both procedures was used, and inpatient rehabilitation (IPR) costs were added for all patients discharged to IPR.

RESULTS

There were 225 simBTKA and 337 staBTKA patients. SimBTKA patients were younger (61 ± 8 vs 66 ± 8 years, P < .001), had lower body mass index (31.3 ± 5.9 vs 34.0 ± 7.2, P < .001), were more predominately male (48% vs 38%, P = .029), and more likely to require IPR as compared with staBTKA patients. There was no difference in total hospital cost for simBTKA as compared with staBTKA ($24,596 ± $5652 vs $24,915 ± $5756, P = .586). Complications were more prevalent in the simBTKA group, including venous thromboembolism (5.4% vs 1.4%, P = .006) and blood transfusions (15.8% vs 6.2%, P < .001).

CONCLUSION

There were higher complication rates with no significant cost savings in actual hospital costs associated with simBTKA, when accounting for the cost of IPR, as compared with staBTKA. The total cost analysis of simBTKA vs staBTKA, using actual cost data, merits further evaluation.

Comparison of postoperative complications and clinical outcomes between simultaneous and staged bilateral total knee arthroplasty

BACKGROUND

Controversy exists regarding the safety of simultaneous vs. staged bilateral total knee arthroplasty (TKA). The purpose of this study was to compare postoperative complication rate and clinical outcomes of simultaneous vs. staged bilateral TKA.

METHODS

A consecutive series of 1074 patients who underwent either simultaneous (759 patients) or staged bilateral (315 patients) TKA from 2004 to 2013 were enrolled in this study. Postoperative complications were categorized as minor or major. Clinical outcome was evaluated at the last follow-up using Knee Society Score (KSS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and range of motion (ROM).

RESULTS

Major complication rate was not statistically different between the two groups. However, minor complication rate was significantly (p < 0.05) higher in the staged TKA group compared to that in the simultaneous TKA group. The median length of stay (LOS) in hospital was 18.0 days after simultaneous TKA vs. cumulated LOS of 34.1 days in the staged group (p < 0.05). Clinical outcome results revealed that there was no significant difference in KSS, WOMAC scores, or ROM between the two groups.

CONCLUSIONS

Therefore, simultaneous bilateral TKA has some advantage such as less length of stay in hospital compared to staged bilateral TKA. However, this procedure should be conducted very carefully, particularly in high-risk patients.

Safety of simultaneous bilateral total knee arthroplasty using an extramedullary referencing system: results from 2098 consecutive patients

INTRODUCTION

Simultaneous bilateral total knee arthroplasty (TKA) has been associated with a high risk of morbidity and mortality. The orthopedic surgeon must, therefore, decide whether bilateral simultaneous TKA is a safe operation to perform and endeavor to decrease the risk of serious complications or even death.

METHODS

This retrospective review included 2098 consecutive patients who underwent bilateral simultaneous TKAs by the protocol used in our institution, including the use of extramedullary instruments to minimize medullary canal invasion and overlapping procedures for both knees to decrease operation time.

RESULTS

The incidence rate of occurred complications was 0.33 % for symptomatic pulmonary embolism, 0.62 % for deep surgical infection requiring revision surgery, 0.05 % for 14-day mortality, 1.14 % for adverse cardiac events, and 0.76 % for postsurgical delirium within the 1-year follow-up.

CONCLUSIONS

Our protocols, including the use of an extramedullary referencing system and overlapping procedures for both knees, may be considered to decrease the perioperative short-term morbidity and 14-day mortality rates in simultaneous bilateral TKA.

Concomitant Total Wrist and Total Elbow Arthroplasty in a Rheumatoid Patient

Background Concomitant arthroplasty has been described to have several benefits over multistage procedures. Ipsilateral total elbow and total shoulder arthroplasty has been reported with good outcomes in upper extremity concomitant arthroplasty. Case Description A 65-year-old woman presented with ipsilateral left-sided wrist and elbow joint degeneration as a result of longstanding rheumatoid arthritis. Concomitant total wrist and total elbow arthroplasty was performed with satisfactory results at both joints. She tolerated the procedure well and had an uneventful clinical course postoperatively. Literature Review Currently, no literature exists that describes one-stage total wrist and total elbow arthroplasty. Individually, total wrist and total elbow arthroplasty have both been reported to result in good outcomes and patient satisfaction. Previous studies have reported the utility of concomitant ipsilateral upper extremity procedures with a one-stage total elbow and total shoulder arthroplasty having been identified as a cost-saving procedure with expedited return to functionality versus a two-stage procedure. Clinical Relevance Patients with ipsilateral degenerative changes in the wrist and elbow should be considered on an individual case basis for concomitant total wrist and total elbow arthroplasty.

Tranexamic Acid Decreases Incidence of Blood Transfusion in Simultaneous Bilateral Total Knee Arthroplasty

Blood management for simultaneous bilateral total knee arthroplasty (TKA) patients is more challenging than in unilateral arthroplasty. We examined if administration of tranexamic acid (TXA) to patients undergoing simultaneous bilateral TKA would reduce blood loss and decrease allogeneic blood transfusion requirements. A retrospective review of 103 patients, 57 in the control and 46 in the TXA group, was performed. There was higher postoperative day 1 hemoglobin in patients receiving TXA (2.95±1.33 versus 4.33±1.19, P<0.0001). There was also a decrease in the transfusion incidence with administration of TXA (17.4% versus 57.9%, P<0.0001). In conclusion, we have shown that TXA is an effective tool in reducing the transfusion rates by almost 70% in simultaneous bilateral total knee arthroplasty.

Bilateral Simultaneous Total Knee Arthroplasty: A Patient-Matched Retrospective Observational Study

Bilateral total knee arthroplasty can be performed either as a staged or simultaneous procedure. We conducted a retrospective comparative study to compare the need for transfusion, the length of procedure, the length of stay, and complications of bilateral simultaneous knee arthroplasty with those of unilateral knee arthroplasty. Sixty-nine patients who underwent bilateral simultaneous knee arthroplasty procedures were compared with a matched control group of 69 patients who underwent unilateral knee arthroplasty. Receiver Operating Characteristic (ROC) curve was used to determine optimum cut-off values. Both groups of patients had a similar age and gender distribution, preoperative haemoglobin and ASA scores. Cumulative transfusion episodes were lower in the bilateral group than twice that of the unilateral group. In multivariate analysis the preoperative haemoglobin level and bilateral procedures were independent factors predicting the need for transfusion. The average length of procedure and length of hospital stay in the bilateral group was less than twice than that of the unilateral group. Advanced age and bilateral procedures were independent predictors of prolonged length of stay. A haemoglobin level of 12.5 g/dL and age of 70 were most suitable cut-off points to predict need for transfusion and occurrence of medical complications respectively. We conclude that bilateral simultaneous knee arthroplasties are safe and cost effective in appropriately selected patients. We recommend avoiding bilateral simultaneous procedures in patients over the age of 70 years and with significant comorbidities.

Perioperative Outcomes Following Unilateral Versus Bilateral Total Knee Arthroplasty

Simultaneous bilateral total knee arthroplasty (SB-TKA) is potentially a cost saving manner of caring for patients with bilateral symptomatic knee arthritis. We performed a retrospective analysis using the 2010-2012 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) to evaluate the risk of perioperative complication following SB-TKA. Demographic characteristics, comorbidities, and 30-day complication rates were studied using a propensity score-matched analysis comparing patients undergoing unilateral TKA and SB-TKA. A total of 4489 patients met the inclusion criteria, of which 973 were SB-TKA. SB-TKA was associated with increased overall complications (P = 0.023), medical complications (P = 0.002) and reoperation (OR 2.12, P = 0.020). Further, total length of hospital stay (4.0 vs 3.4 days, P < 0.001) was significantly longer following bilateral surgery.

Functional outcomes of simultaneous bilateral versus unilateral total knee arthroplasty

Many patients in need of total knee arthroplasty (TKA) have bilateral symptoms and require surgery to both extremities. Performance of a bilateral procedure under a single anesthetic provides a reduced hospitalization time, an isolated anesthesia risk, a single rehabilitation, and substantial cost savings. While most current research examines postoperative complication rates, the primary purpose of TKA is the alleviation of pain and improved quality of life. The purpose of this study was to assess pain and functional outcomes associated with simultaneous bilateral TKA. The authors believe that patients with advanced destructive arthritis to numerous joints cannot achieve complete restoration of their functional status until comprehensive treatment of their disease process occurs. A retrospective review of 697 TKAs in 511 consecutive patients with bilateral knee arthritis was performed. Patients underwent either simultaneous bilateral TKA (n=186), performed sequentially under the same anesthetic, or unilateral TKA (n=325). The same intra- and postoperative protocols were followed in each group. There was no statistically significant difference in postoperative pain, represented by Knee Society Score (P=.161). However, there was a significantly higher postoperative functional outcomes-including increased total range of motion (P=.001), flexion (P=.003), and function score (P<.001)-associated with bilateral TKA. Simultaneous bilateral TKA is an effective treatment option and may be worth possible added risk in appropriate patients because it produces a better functional outcome.

Disparate postoperative results in the first and second knees on simultaneous bilateral total knee arthroplasty

We hypothesized that the circumstances of the two consecutive operations of a simultaneous bilateral total knee arthroplasty (TKA) are different, and could lead to different outcomes of overlapping bilateral TKAs. Both knees of 420 subjects were evaluated in the current study. In the second TKA, there were more incidence rates of outlier in mechanical femoro-tibial angle (16.2% vs. 9.0%), more blood loss (735 vs. 656 mL), and longer operation time (61, 58 minutes respectively), as compared to the first TKA, while no significant differences in clinical outcomes. In conclusion, there were no significant differences in the clinical outcomes even though few distinct outcomes due to different circumstances of the surgery. Awareness of these findings can help the continued success of bilateral TKA in an increasing patient population.

Safety of bilateral total knee arthroplasty in morbidly obese patients

There has been an increase in the prevalence of morbid obesity and the demand for total knee arthroplasty (TKA). Physicians must help patients with bilateral knee arthritis to make informed decisions regarding whether to undergo staged, sequential, or simultaneous TKA. The purpose of this study was to evaluate the perioperative complications of 2-team simultaneous bilateral TKA in the morbidly obese. The authors performed a retrospective review of the records at a single tertiary hospital from 1997 to 2007 and identified 35 morbidly obese (body mass index [BMI] greater than 40 kg/m(2)) patients who had undergone unilateral TKA, as well as 42 morbidly obese and 79 nonobese (BMI less than 30 kg/m(2)) patients who underwent simultaneous bilateral TKA. Clinical, operative, and postoperative variables and complication rates were recorded. Clinical variables were similar between the morbidly obese TKA patients. The bilateral group had significantly increased operative times (132.4 vs 115.5 minutes; P<.01), intravenous fluids (2556.1 vs 2114.7 mL; P=.03), percentage transfused (64.2% vs 11.4%; P<.01), days in the hospital (3.6 vs 3.2 days; P=.03), and discharge rates to rehabilitation facility (72.7% vs 48.6%; P=.01). Major and minor complications were few and comparable, with the need for manipulation under anesthesia in unilateral TKA (11.4%; P=.04) as the only significant difference between groups, including when comparing bilateral nonobese TKAs with bilateral morbidly obese TKAs. The authors feel that morbidly obese patients may undergo 2-team simultaneous bilateral TKA after careful discussion regarding some of the differences in short-term outcomes.

Clinical outcomes of bilateral single-stage unicompartmental knee arthroplasty

BACKGROUND

Deciding whether to treat patients with bilateral arthritis with two-stage or bilateral single-stage arthroplasties is a cause of considerable debate in orthopaedic surgery.

METHODS

A total of 394 cemented Unicompartmental Knee Arthroplasties (UKA) were performed in this unit between 2006 and 2010. A retrospective review identified 38 patients (76 knees) who underwent bilateral Single-Stage Sequential UKA, performed by a single surgeon.

RESULTS

The mean BMI was 29.8 and the majority of patients were ASA grade 2. The mean duration of follow-up was 30 months. The mean total tourniquet time was 83 min. The mean post-operative haemoglobin was 11.8 and no patient required blood transfusion. The mean time to mobilisation was 18 h and the average length of stay was 3.5 days. This compares favourably with an institutional average length of stay of two days for a single UKA. There was a significant improvement in the mean pre- to post-operative OKS (from 14 to 34, p<0.0001). One patient required operative fixation of a tibial plateau fracture after sustaining a mechanical fall two months following surgery. There were no other major complications, including thrombo-embolic events or deep infections. Two patients required excision of a superficial suture granuloma.

CONCLUSIONS

Bilateral Single-Stage Sequential UKAs provide significant improvement in patient function and can be performed safely with a low complication rate. Patients can benefit from a single hospital admission and anaesthetic whilst the shorter total in-patient stay reduces costs incurred by the hospital.

LEVEL OF EVIDENCE

IV.

Comparison of clinical outcome between simultaneous-bilateral and staged-bilateral total knee arthroplasty: a systematic review of retrospective studies

The purpose of this study is to conduct a systematic review assessing the clinical outcome associated with Simultaneous bilateral and staged bilateral total knee arthroplasty (TKA). A literature search for eligible studies was conducted. Eighteen retrospective comparative studies were included. Pooled results showed that the prevalence of mortality at 30 days postoperatively, pulmonary embolism, blood transfusion rate were significantly higher in simultaneous TKA group. A significantly lower rate of deep infection and revision were found in simultaneous TKA. No significant difference was seen in regard to neurological complications, deep-vein thrombosis, cardiac complications, superficial infection. Compared with staged bilateral TKA, simultaneous bilateral TKA is associated with higher rates of mortality, pulmonary embolism and blood transfusion, while decreasing the risk of deep infection and revision rate.

Unilateral vs bilateral total knee arthroplasty risk factors increasing morbidity

Because surgeons are electing to perform simultaneous bilateral total knee arthroplasty (TKA), it is important to identify which patients are at increased risk. We performed a retrospective cohort analysis of 150 patients with unilateral TKA vs 150 patients with simultaneous bilateral TKA. The bilateral group demonstrated a 2.1 times greater mean overall complication rate as well as increased transfusion rates. Patients older than 70 years exhibited significantly higher complication rates. Having a preexisting pulmonary disorder in the bilateral cohort carried nearly a 3-fold risk of complications. Patients with body mass indices greater than 30 displayed a complication rate of 0.97 in the bilateral group as opposed to 0.44 in the control group. Our study demonstrated that age, body mass index, and a preexisting pulmonary disorder resulted in increased complications.

Perioperative complications of simultaneous versus staged unicompartmental knee arthroplasty

BACKGROUND

The complication risk of staged versus simultaneous total knee arthroplasty continues to be debated in the literature. Previous reports suggest unicompartmental knee arthroplasty provides a more rapid functional recovery than total knee arthroplasty. However, little data exist on whether simultaneous unicompartmental knee arthroplasty can be performed without increasing the perioperative risk compared with staged unicompartmental knee arthroplasty.

QUESTIONS/PURPOSES

We therefore asked if there is an increased risk of perioperative complications with bilateral simultaneous unicompartmental knee arthroplasty.

METHODS

We retrospectively compared 141 patients (282 knees) treated with staged unicompartmental knee arthroplasty with 35 patients (70 knees) treated with simultaneous unicompartmental knee arthroplasty to evaluate perioperative complications and short-term results assessed by Knee Society function scores and the Lower Extremity Activity Scale.

RESULTS

Patients who underwent simultaneous unicompartmental knee arthroplasty had a shorter cumulative operative time (109 versus 122 minutes), a shorter cumulative length of hospital stay (1.7 versus 2.5 days), higher Knee Society function scores at most recent followup (88 versus 73), and higher Lower Extremity Activity Scale (12.0 versus 10.2) without a difference in perioperative complications. The simultaneous cohort was younger (59 versus 63 years of age) and less obese (body mass index 31 versus 33 kg/m(2)) than the staged group.

CONCLUSIONS

Although we found a substantial bias for performing simultaneous unicompartmental knee arthroplasty in younger and less obese patients, these data suggest it can be performed without increasing perioperative morbidity or mortality in this patient population.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Perioperative safety of two-team simultaneous bilateral total knee arthroplasty in the obese patient

Background

Although the rates of perioperative morbidity and mortality with simultaneous bilateral total knee arthroplasty remain a concern, multiple studies have shown the procedure to be safe in selected patient populations. Evidence also remains mixed regarding the outcomes of total knee arthroplasty in obese patients. The purpose of this paper is to compare the rates of perioperative morbidity and mortality in consecutive obese patients undergoing two-team simultaneous bilateral total knee arthroplasty and unilateral total knee arthroplasty.

Methods

The records on all two-team simultaneous total knee arthroplasties and unilateral total knee arthroplasties from October 1997 to December 2007 were reviewed. A total of 151 patients with a body mass index (BMI) >30 undergoing two-team simultaneous total knee arthroplasty and 148 patients with a BMI >30 undergoing unilateral total knee arthroplasty were retrospectively reviewed and analyzed to determine perioperative morbidity and mortality as well as one-year mortality rates.

Results

Preoperative patient characteristics did not show any significant differences between groups. The simultaneous bilateral group had significantly longer operative times (127.4 versus 112.7 minutes, p < 0.01), estimated blood loss (176.7 versus 111.6 mL, p = 0.01), percentage of patients requiring blood transfusion (64.9% versus 13.9%, p < 0.01), length of hospital stay (3.72 versus 3.30 days, p < 0.01), and percentage of patients requiring extended care facility usage at discharge (63.6% versus 27.8%, p < 0.01). No significant difference between unilateral and bilateral groups was seen in regards to total complication rate, major or minor complication subgroup rate, or any particular complication noted. Doubling the variables in the unilateral group for a staged total knee arthroplasty scenario did create significant increases over the simultaneous data in almost every data category.

Conclusions

Two-team simultaneous total knee arthroplasty appears to be safe in obese patients, with similar complication rates as compared to unilateral procedures. Two-team simultaneous total knee arthroplasty also appears to have potential benefits over a staged procedure in the obese patient, although more study is required regarding this topic.

Clinical outcomes after simultaneous bilateral total knee arthroplasty: comparison to unilateral total knee arthroplasty and healthy controls

The purpose of this study was to evaluate the functional outcomes of persons who underwent simultaneous bilateral total knee arthroplasty (TKA) compared to subjects who underwent unilateral TKA and a healthy control group. Fifteen subjects who underwent primary bilateral TKA and 15 sex, age, and body mass index-matched subjects who underwent primary unilateral TKA were observed prospectively for 2 years. Subjects in both surgical groups showed significant improvement in Knee Outcome Scores, Short Form 36 physical component scores, Timed Up and Go, and stair-climbing tasks (P <or= .004). No differences in final outcomes were found between surgical groups. In addition, most 2-year clinical measures were no different between the surgical and control groups. Subjects medically appropriate for bilateral TKA should be afforded this option.

Simultaneous bilateral total knee replacement: a persistent controversy

The benefits and risks of Simultaneous Bilateral Total Knee Replacement (SBTKR) remain controversial. A review of the English speaking literature was undertaken and found that many papers took staunch positions either for or against the procedure. It was also noted that earlier papers supporting SBTKR suggested cost benefits. There was a huge disparity in the incidence of mortality and morbidity and it was not possible to compare many papers, because in some medically frail patients were excluded from the SBTKR cohorts. In large published series the proportion of patients having a SBTKR varied between 3% and 70%. Many, but not all, series highlighted age and co-morbidity as risk factors. Overall there was no clear case for or against SBTKR. The evidence suggested that careful preoperative assessment and patient selection on a strict protocol were essential. The procedure should be confined to hospitals where high dependency nursing is readily available and the literature indicated that the risk is less in high through-put units. By refining preoperative assessment and preparation it can be a safe and effective procedure in an appropriate clinical setting for postoperative care.

A comparison of two rehabilitation protocols after simultaneous bilateral total knee arthroplasty: a controlled, randomized study

Post-operative outcomes after simultaneous bilateral total knee arthroplasty in 115 patients randomly assigned to two rehabilitation protocols were compared. The traditional-protocol group performed a series of exercises on one leg and then repeated the same sequence on the other leg. The alternate-protocol group performed the same exercises, but alternated between legs with each individual repetition. Symptoms and function were assessed pre-operatively and at 1, 3, 6 and 12 months post-operatively. The alternate-protocol group had lower visual analogue pain scale scores in the early post-operative period, as well as higher Knee Society Scores and SF-12 physical and mental health summary scores after 1 and 3 months compared with the traditional-protocol group, but there were no differences between the two groups from 6 months post-operatively. There were no significant differences between the groups in terms of range of knee motion or incidence of deep vein thrombosis. The alternate-protocol for rehabilitation resulted in an early return to function and decreased pain levels following simultaneous bilateral total knee arthroplasty and was associated with the potential to produce more positive emotional states and earlier functional independence.

An acute care episode of a patient following bilateral total knee arthroplasty

More patients with bilateral joint problems are choosing to go through one surgery to replace both joints simultaneously rather than having two separate surgeries. The goals of physical therapy following the surgery are to decrease pain, maximize range of motion (ROM) and strength, improve ambulation, and improve overall function. Few studies have focused on the importance of the acute phase of rehabilitation and most concentrate instead on long-term outcomes and outpatient care. The patient was a 62-year-old male diagnosed with osteoarthritis of both knees. The day before the initial physical therapy evaluation, the patient underwent a bilateral total knee arthroplasty. By the end of his stay, active knee ROM increased to -6 degrees to 88 degrees on the right and -6 degrees to 83 degrees on the left. Passive ROM also increased to -5 degrees to 90 degrees on the right and -5 degrees to 86 degrees on the left. The patient was able to perform supine to sit transfers with supervision and sit to stand transfers with contact guard assistance and his ambulation progressed to wvalking 100 feet on level surfaces with a rolling walker and supervision. The positive gains of this patient suggest the potential value of high motivation combined with early aggressive physical therapy.

Staged bilateral hip or knee arthroplasties

PURPOSE

To compare the operating time, amount of blood transfused, length of hospital stay, and early complications (within 6 months) between 2-week staged bilateral arthroplasties and matched randomised controls undergoing unilateral arthroplasties.

METHODS

From October 1992 to October 2000, 90 patients who underwent bilateral hip or knee arthroplasties with a 2-week interval were compared with matched randomised controls undergoing unilateral arthroplasties. A single surgeon performed all procedures.

RESULTS

After the match-up process, 30 pairs of patients were included in the analysis. There were no significant differences in the operating times, amount of blood transfused, and early complication rates. The mean difference in length of hospital stay was significant (t=-3.552, df=29, p<0.001).

CONCLUSION

Compared to staged procedures with an interval months apart, staged sequential arthroplasty with a 7- to 10-day interval during one hospital admission is more efficient, as it facilitates earlier rehabilitation without higher complication rates, and entails shorter hospital stays.

Safety of simultaneous bilateral total knee arthroplasty. A meta-analysis

BACKGROUND

The safety of simultaneous bilateral total knee replacement remains controversial. Some studies have demonstrated a higher rate of serious complications, including death, following bilateral procedures, whereas others have suggested no increase in the complication rate. The objective of this meta-analysis was to compare the safety of simultaneous bilateral total knee replacement with that of staged bilateral and unilateral total knee replacements.

METHODS

A computerized literature search was conducted to identify all citations, from 1966 to 2005, concerning bilateral total knee replacement. All of the English-language abstracts were obtained. A multistage assessment was then performed to identify articles fulfilling the inclusion criteria for the study. All randomized, prospective studies reporting the outcome of bilateral total knee replacement were included. The details of the reported data were extracted, and an extensive analysis of relevant variables was carried out.

RESULTS

One hundred and fifty published articles were identified, and eighteen that included a total of 27,807 patients (44,684 knees) were included in the meta-analysis. There were 10,930 unilateral total knee replacements, 16,419 simultaneous bilateral total knee replacements, and 458 staged bilateral total knee replacements with at least three months between the operative procedures. The prevalences of pulmonary embolism (odds ratio = 1.8), cardiac complications (odds ratio = 2.49), and mortality (odds ratio = 2.2) were higher after simultaneous bilateral total knee replacement. The prevalence of deep venous thrombosis was lower after simultaneous bilateral total knee replacement, but this difference was not significant. The complication rates after the staged bilateral total knee replacements were similar to those in the patients who had undergone unilateral total knee replacement only.

CONCLUSIONS

Compared with staged bilateral or unilateral total knee replacement, simultaneous bilateral total knee replacement carries a higher risk of serious cardiac complications, pulmonary complications, and mortality. The period of time between staged procedures that would eliminate these increased risks could not be determined from this study.

LEVEL OF EVIDENCE

Therapeutic Level III.

The practice of bilateral, simultaneous total knee replacement in Scotland over the last decade. Data from the Scottish Arthroplasty Project

The issue of the safety of performing simultaneous, bilateral total knee replacement (SBTKR) for patients with bilateral knee osteoarthritis remains controversial. Several small series have reported inconclusive findings and the few large series published are contradictory. We present data retrieved from the Scottish Arthroplasty Project on over 19,000 total knee replacements (TKR) performed in Scotland between 1989 and 1999. The trends in the practice of SBTKR are shown together with the associated mortality from the procedure compared with unilateral or staged, bilateral TKR. The data shows that there was no statistically significant difference in the 90-day mortality between unilateral TKR, staged TKR or SBTKR. In addition, the length of stay for SBTKR has reduced, equaling that of unilateral TKR since 1993. Despite an initial increase in the percentage of consultants performing SBTKR early in the decade, since 1993, only approximately 25% of knee arthroplasty surgeons in Scotland per year ever performed a SBTKR.

Debate: simultaneous bilateral knee replacements: the outcomes justify its use

The purpose of this paper is to assess the morbidity, mortality, and clinical outcome of simultaneous bilateral total knee arthroplasty. We reviewed 4100 simultaneous bilateral total knee replacements. The knees were subjected to two Kaplan-Meier survival analyses, with failure equal to revision for aseptic loosening and failure equal to patient death. Complications and Knee Society scores were considered. The average Knee Society knee score was 90 points 3 years postoperatively and 87 points 10 years postoperatively. The complication rates were as follows: deep infection (0.8%), superficial infection (0.3%), cardiac (6 arrhythmia, 5 congestive heart failure, 1 cardiac insufficiency, 3 complete heart block, 2 myocardial infarction and cardiac arrest, and 14 myocardial infarction only) (1.5%), intestinal ileus (0.5%), gastrointestinal ulcer (0.4%), thrombophlebitis (0.9%), cerebrovascular accident (0.3%), and urinary (1 BPH-obstruction, 4 renal failure, 2 transurethral resection of the prostate, 16 urinary tract infection, and 2 urinary retention/incontinence) (1.2%). The 10-year prosthesis survival probability was 98.3%. The 10-year patient survival probability was 78.6%. Twenty-five (1.2%) patients died within the first postoperative year. The patients who died within 1 year postoperatively were older than the rest of the group. Higher age and male gender were factors related to increased mortality. The complication rates and clinical outcomes were similar to unilateral total knee arthroplasty. With regard to death early in the postoperative course, simultaneous bilateral total knee arthroplasty may pose a greater risk to the patient than a unilateral procedure. However, the early deaths may be related to older age at the time of surgery.

Debate: bilateral simultaneous total knee arthroplasty

Controversy persists regarding the value of doing bilateral simultaneous total knee arthroplasty. Advocates of this procedure focus on economic costs, patient satisfaction, and quicker return to function as compared with bilateral staged total knee arthroplasty. Those in opposition focus on increased complication rates that question the overall safety of this operative procedure. The purpose of this discussion is to review the orthopaedic literature, concentrating on the reported advantages and disadvantages of bilateral simultaneous total knee arthroplasty in hopes of providing the surgeon with information valuable in determining the safety and efficacy of this procedure.

Perioperative morbidity in bilateral one-stage total knee replacements

A retrospective review was done on 501 patients who had bilateral sequential one-stage total knee replacements from September 1995 to April 2000 to evaluate perioperative (inhospital) morbidity. One thousand two knee replacements were done with the patients receiving regional anesthesia, on 286 women and 215 men with an average age of 66 years. The average transfusion requirement was 2.8 units of blood per patient. There were no deaths, myocardial infarctions, or cerebrovascular accidents. The mean length of hospital stay was 7.2 days. One hundred forty-four perioperative complications were observed in 109 patients (21.8%). These complications included 27 arrhythmias (5%), one congestive heart failure (0.2%), 65 lower extremity deep venous thromboses (13%), 14 fat emboli (3%), and two pulmonary emboli (0.4%). Other major complications were pneumonia (1%), acute renal failure (0.4%), ileus (2%), and mental status changes (2%). Wound complications included two deep infections (0.4%), three hematomas (0.6%), and five delayed wound healings (0.9%). According to the current study the perioperative morbidity and mortality is acceptable if the procedure is used for selected patients. Patients with significant comorbidities should have a staged bilateral total knee replacement.

An evaluation of the safety and efficacy of simultaneous bilateral total knee arthroplasty

This study directly compared the clinical and radiographic results and patient satisfaction of a group of simultaneous, bilateral total knee arthroplasties (92) with a year of surgery matched unilateral total knee arthroplasties (92). Death within 1 month of surgery occurred in 1 bilateral patient and no unilateral patients. Significant cardiorespiratory complications were recorded in 6 bilateral patients and 2 unilateral patients. Patients with pre-existing cardiorespiratory conditions were particularly at risk. Analysis revealed a 98% 7-year survivorship for unilateral procedures and 97% for bilateral. In this study, 95% of bilateral patients stated they would choose the same option again.

Comparison of simultaneous bilateral with unilateral total knee arthroplasty in terms of perioperative complications

BACKGROUND

Previous studies have demonstrated an increased rate of perioperative complications and morbidity following simultaneous bilateral total knee arthroplasty compared with the rate following unilateral total knee arthroplasty. The purpose of this study was to compare the rate of perioperative complications and morbidity associated with simultaneous bilateral total knee arthroplasty with that associated with unilateral total knee arthroplasty.

METHODS

The records on all bilateral total knee arthroplasties performed between January 1994 and June 2000 and unilateral total knee arthroplasties performed between January 1995 and June 2000 were retrospectively reviewed. The records on 514 unilateral total knee arthroplasties and 255 bilateral total knee arthroplasties were analyzed to determine demographic information, preoperative comorbidities, perioperative complications, and thirty-day and one-year mortality rates.

RESULTS

The rates of some perioperative complications, including myocardial infarction, postoperative confusion, and the need for intensive monitoring, were greater after the bilateral arthroplasties. However, the thirty-day and one-year mortality rates and the risks of pulmonary embolism, infection, and deep venous thrombosis were similar for the two groups.

CONCLUSIONS

The risk of perioperative complications associated with bilateral simultaneous total knee arthroplasty was slightly increased compared with that associated with unilateral total knee arthroplasty, but the mortality rates were similar. Ultimately, the decision to proceed with simultaneous knee replacement should depend on patient preference through informed choice.

Simultaneous bilateral, staged bilateral, and unilateral total knee arthroplasty. A survival analysis

BACKGROUND

The rates of perioperative morbidity and mortality are areas of concern associated with simultaneous bilateral total knee replacement. The purpose of this paper was to compare the rates of morbidity and mortality and the clinical outcome in large groups of consecutive patients undergoing simultaneous bilateral total knee replacement, unilateral total knee replacement, or staged bilateral total knee replacement.

METHODS

A total of 6200 total knee replacements, performed in 3998 patients between 1983 and 2000, consisted of 2050 simultaneous bilateral, 1796 unilateral, and 152 staged bilateral total knee replacements. A review of each group was conducted to compare the rates of morbidity and mortality, the survival of the prosthesis, and the clinical outcome. Kaplan-Meier survival analyses were performed with failure defined as revision because of aseptic loosening and as patient death. Complications and Knee Society scores were compared throughout the fifteen-year follow-up period (average, 4.3 years of follow-up).

RESULTS

The unilateral group had significantly lower Knee Society scores than the simultaneous bilateral group (p < 0.0001 up to twelve years, and p = 0.0067 at fifteen years) across all postoperative time-intervals. The percentage of patients who had thrombophlebitis was significantly higher in the simultaneous bilateral group (0.9%) than in the unilateral group (0.3%) (p = 0.0326). No significant differences were found with regard to prosthetic failure, cardiac complications, and the rates of death in the three groups. Ten years postoperatively, the simultaneous bilateral group had a significantly higher rate of patient survival than did the unilateral group (78.6% compared with 72.0%) (p = 0.0062).

CONCLUSIONS

The significantly higher rate of thrombophlebitis in the simultaneous bilateral group compared with that in the unilateral group may represent a greater risk to those patients. However, we believe that when there are adequate indications for bilateral total knee replacement, simultaneous bilateral arthroplasty is beneficial to patients, with a minimal increase in the risk of death or other complications compared with that associated with unilateral and staged procedures.

The impact of medicare reimbursement policies on simultaneous bilateral total hip and knee arthroplasty

In October of 1992, Medicare reimbursement decreased by 50% for a second total hip or knee arthroplasty performed as part of a simultaneous bilateral procedure. The Medicare records of 67726 patients who underwent total hip and knee arthroplasty were reviewed using data from the New York State Department of Health in the period from October 1, 1989, to September 30, 1996. Simultaneous bilateral total hip arthroplasties represented 1.8% of the total number of total hip replacements performed in fiscal year 1991 (60 of 3418) compared with 1.7% (77 of 4547) performed in fiscal year 1994 (P=.902). Similarly, the number of simultaneous bilateral total knee arthroplasties did not change significantly, with simultaneous bilateral procedures representing 5.9% of the total number of total knee replacements performed in fiscal year 1991 (214 of 3620) compared with 6.2% (369 of 5,931) performed in fiscal year 1994 (P=.568).

A comparison of bilateral vs. unilateral total knee arthroplasty mobilised using a flexion regime

Fifty six consecutive, primary simultaneous bilateral total knee arthroplasties were prospectively compared to 172 consecutive, primary unilateral total knee arthroplasties. Outcome measures included length of stay, analgesic and blood requirement as well as range of movement and functional scores. All procedures were performed by a single surgeon using a uniform technique, including a postoperative flexion regime. Range of movement, analgesic requirement and complication rates were similar in each group. The bilateral cases stayed in hospital on average 1.7 days longer and required considerably more blood.

One-staged contralateral or ipsilateral total hip and total knee arthroplasty

One-staged ipsilateral and contralateral total hip and total knee arthroplasties were compared. A total of 103 patients underwent a 1-staged total knee arthroplasty and total hip arthroplasty between January 1975 and July 1997 (67 contralateral and 36 ipsilateral patients). No prostheses were found to be loose or revised. The contralateral group had a 10.5% hip dislocation rate, and the ipsilateral group had an 8.3% hip dislocation rate. Most of the patients were discharged home (contralateral, 66%; ipsilateral, 56%). There was no significant difference in survival between the contralateral and ipsilateral groups. There was only 1 death within 3 months of the operation. The severity of these patients' deformity may necessitate these procedures be done at 1 operation with consideration of mortality and morbidity risks.

Intraoperative monitoring for safety of bilateral total knee replacement

Cardiopulmonary hemodynamics in 79 consecutive patients who had one-stage bilateral total knee replacements were monitored prospectively with a pulmonary artery catheter. The pulmonary vascular resistance, wedge pressure, pulmonary artery pressure, and systemic vascular resistance were measured before skin incision, 5 to 10 minutes after implanting the first total knee replacement, and after the second knee replacement. The second knee replacement was cancelled in five patients because the pulmonary vascular resistance after the first knee replacement was more than double the baseline, or above 200 dyne/second/cm(5). No patient had clinical symptoms of fat embolism during the postoperative course. Patient predictive factors, or the use of pulse oximetry readings instead of a pulmonary artery catheter, were not predictive of intraoperative elevation of pulmonary vascular resistance. For this reason, the safety of this operation for the patient requires that intraoperative measurement of hemodynamic parameters of embolism be done.

Simultaneous bilateral total knee arthroplasties: who decides?

The purpose of the current retrospective review was to compare the results of 1498 patients having 1090 simultaneous bilateral total knee arthroplasties and 958 unilateral total knee arthroplasties in a 3-year period, focusing on perioperative complications, length of hospital stay, and discharge disposition. Gender, age, diagnosis, and weight were similar between the groups. Patients undergoing simultaneous bilateral total knee arthroplasties had statistically significant higher amounts of intraoperative blood loss, with more patients requiring blood transfusion, and a higher average number of units of blood transfused compared with patients undergoing unilateral total knee arthroplasty. Overall, a significantly higher incidence of gastrointestinal complications was reported in patients who had simultaneous bilateral knee arthroplasties compared with patients who had unilateral knee arthroplasty. Comparing age subgroups within the unilateral group revealed significantly higher incidences of pulmonary, neurologic, cardiac, and genitourinary complications among patients 80 years or older versus patients younger than 80 years. Patients having simultaneous bilateral arthroplasties who were 80 years or older had significantly higher incidences of pulmonary, neurologic, and cardiac complications than patients younger than 80 years in that same group. These results suggest that age, not procedure, has a more significant role in the perioperative morbidity of total knee arthroplasty. Based on the results from the current study and previous literature documenting patient preference, patient satisfaction, efficacy, and outcomes comparable with those of patients having unilateral total knee arthroplasty, the authors continue to offer patients the option of simultaneous bilateral total knee arthroplasties.

Is obesity a contraindication to bilateral total knee arthroplasties under one anesthetic?

Three-hundred sixteen patients who underwent 405 primary knee replacements between January 1994 and June 1999 were reviewed for the incidence of local wound and systemic complications after unilateral and simultaneous bilateral total knee arthroplasties. A body mass index of 30 or greater was used to define obesity, and patients were divided into four groups based on obesity and whether they were undergoing unilateral or bilateral total knee arthroplasties. Preoperative and postoperative knee scores were not significantly different for any patient group. Local wound complication rates did not differ between any of the study groups. Patients who were not obese who underwent unilateral total knee arthroplasty had lower systemic complication rates (3%) than the other groups; however, there was no significant difference in complication rates between patients with obesity who underwent unilateral or simultaneous bilateral total knee arthroplasties. Based on these findings, obesity does not seem to be a contraindication to bilateral total knee arthroplasties under one anesthetic.

Sequential bilateral total knee arthroplasty under 1 anesthetic in patients > or = 75 years old: complications and functional outcomes

The objectives of this study were to determine the perioperative surgical and medical risks associated with sequential bilateral total knee arthroplasty (TKA) in patients > or = 75 years old and to assess their functional status and overall level of satisfaction at follow-up. Study participants were 82 consecutive patients > or = 75 years old who underwent a sequential bilateral TKA and 82 matched patients who underwent a unilateral TKA. There were 46 postoperative complications in the bilateral TKA group compared with 27 in the unilateral TKA group (P = .003). Postoperative cardiovascular complications were significantly greater in the sequential bilateral TKA group and were associated significantly with preoperative cardiovascular comorbidity. The mean Modified Hospital for Special Surgery knee score was rated as good (mean, 63.5 out of 80), and 95% of patients rated their knees as excellent or good at follow-up. Sequential bilateral TKA in patients > or =75 years old results in high patient satisfaction and good functional status at follow-up; however, there is an increased risk of cardiovascular complications during the postoperative period in bilateral sequential TKA patients when compared with a matched cohort of unilateral TKA patients.

Patient outcomes after knee replacement

A prospective, observational cohort investigation was performed to help understand the impact of knee replacement on patients with knee osteoarthritis in community practice. Of those, 291 patients (330 knees) were eligible and willing to participate. Forty-eight orthopaedic surgeons referred 563 patients from 25 institutions within the state of Indiana. Demographics, patient completed health status, satisfaction, independent radiographic measures, surgeon reported intraoperative factors, hospital discharge factors, and independent physical examinations were recorded. A minimum 2-year followup was obtained in 92% of the patients. At followup, 88% were satisfied, 3% were neutral, and 9% were dissatisfied with the results of their knee surgery. The physical composite score improved from 27.4 +/- 0.4 (range, 13.3-50.3) to 37.7 +/- 0.7 (range, 12.9-61.3) at two years. Maximal improvement in physical composite score was seen in patients who had their surgery performed in institutions that performed greater than 50 knee replacements per year in patients with Medicare insurance; who had a better mental health status at baseline; who had surgery performed on Monday, Friday, or Saturday; who were older; who were treated with a posterior cruciate sparing device; and who had worse preoperative function. A lower likelihood of complications were found with surgeons who performed greater than 20 knee replacements per year; midweek surgeries; in patients with more severe preoperative knee dysfunction; patients with fewer comorbidities; patients with less preoperative stiffness; patients being treated by younger surgeons; and in patients undergoing unilateral knee replacement. Among voluntarily participating physicians, knee replacement can be a highly effective medical technology with high levels of patient satisfaction and low rates of complications.