Bilateral Hip Arthroplasty: When Is It Safe to Operate the Second Hip? A Systematic Review

Simultaneous bilateral total hip arthroplasty-a survey of Irish orthopaedic surgeons' practice

BACKGROUND

Bilateral total hip arthroplasty may be performed simultaneously (SIMTHA) or in two staged operations.

AIM

To assess attitudes towards and utilization of SIMTHA in Irish orthopaedic practice, and to assess patient and surgeon factors which are associated with the management of bilateral hip arthritis.

METHODS

A 16-question electronic survey (Google Forms) was distributed via email to consultant Irish orthopaedic surgeons who perform total hip arthroplasty, followed by a reminder 1 month later. A p value < 0.05 was considered significant.

RESULTS

There were 53 responses from arthroplasty surgeons, with 28% reporting they never perform SIMTHA, 26% have performed ≤ 5 SIMTHA, and 46% do ≥ 1 SIMTHA per year. Amongst the 15 surgeons who do not do SIMTHA, 60% reported a preference for staged arthroplasty, 20% felt it was not feasible in their institution, and a third reported a lack of experience with SIMTHA. There was a significant association between not performing SIMTHA and years of consultant experience (p = 0.002). There were no institutional guidelines on eligibility criteria for SIMTHA. The most common time interval for staged bilateral arthroplasty was 6-12 weeks (60%). Overall, 56% of surgeons felt SIMTHA is underutilised in the Irish healthcare system; this was associated with greater SIMTHA volume (p = 0.023).

CONCLUSION

Half of the Irish arthroplasty surgeons report SIMTHA is a regular aspect of their practice. Performing SIMTHA is associated with greater arthroplasty volume, more recent consultant appointments, and a perception that the operation is underutilised.

Bilateral Total Ankle Arthroplasty

Patients with bilateral ankle arthritis have higher rates of primary and secondary/inflammatory arthritis and a more debilitating condition than those with unilateral pathology. The limited bilateral total ankle arthroplasty (TAA) literature supports both 1-surgeon and 2-surgeon team bilateral TAAs as safe and effective with comparable improvements in patient-reported outcome measures (PROMs), complications, reoperations, and prosthesis survival as unilateral TAA and staged bilateral TAA. Additional benefits of bilateral arthroplasty supported in the hip and knee literature include cost reduction, noninferior and even superior perioperative complication profiles, improved PROM and satisfaction, shorter recovery time, early rehabilitation, and less time away from employment.

Outcomes following staged bilateral total hip replacement: does first-side surgery predict the second?

INTRODUCTION

Patient-reported outcome measures (PROMs) for bilateral staged total hip replacements (THRs) were reviewed to determine whether first-side surgery can predict second-side outcomes.

METHODS

A retrospective review was undertaken of a consecutive cohort of staged bilateral THRs using the same approach, implant and technique, from August 2009 to February 2020. Minimal important change (MIC) in PROMs was set at ≥5.

RESULTS

A total of 296 consecutive staged bilateral THRs were performed in 148 patients. Mean time interval between sides was 25 months (range 2-102). Mean age was 63.2 years for the first side and 65.3 years for the second; 62.8% of patients were female. Mean body mass index was 31.08 for the first side, increasing to 31.57 for the second side (p = 0.248). One-year follow-up PROMs were available for 96.6% and 92.5% of the first and second side, respectively. Mean PROMs improvement at 1 year was 26.4 for the first side and 25.1 for the second side (p = 0.207). Some 97.9% of patients achieved MIC for the first side and 96.3% for the second side (p = 0.092). Eight patients failed to reach an MIC on one side, all were female (p < 0.001); however, MIC was achieved for the contralateral side. Seven of eight patients (87.5%) achieved MIC by 2 years.

CONCLUSIONS

This study identified no significant difference between first- and second-side PROMs improvements following staged bilateral THRs at 1-year follow-up. Failure to reach MIC on one side does not preclude success on the other. Female patients were more prone to not reach MIC at 1 year, but improvement was still subsequently achieved in the majority of cases. The informed consent process is able to reflect this expectation.

Perioperative nursing care for hip arthroplasty patients with concomitant hypertension: A minireview

Hip replacement (HA) is mainly indicated for the elderly, who generally suffer from various underlying diseases such as hypertension. This article provides a review of the key points of perioperative nursing care for patients with hypertension undergoing HA. It analyzes the key points of care during the perioperative period (preoperative, intraoperative, and postoperative) and proposes directions for the development of perioperative nursing care for HA. The prognosis for patients can be improved through the modification of traditional medical approaches and the application of new technologies and concepts.

Unilateral versus simultaneous bilateral total hip arthroplasty. The Belgian experience

Bilateral hip osteoarthritis is frequent. The safety and patient selection for simultaneous bilateral total hip arthroplasty (SBTHA) are still debated. The purpose of this article is to share our experience and assess if performing SBTHA carries more risk than unilateral total hip arthroplasty (UTHA).

METHODS

A retrospective data analysis was performed on 468 patients who underwent either UTHA (418 patients) or SBTHA (50 patients) using a direct anterior approach between June 2016 and December 2020. Apart from SBTHA patients being significantly younger, there was no significant preoperative difference in demographics, comorbidities, surgical variables and biological values between the two groups. Primary outcomes were 90-days emergency room (ER) visit and readmission, as well as 90-days minor and major complications. Secondary outcomes were length of stay (LOS), operative time and blood loss.

RESULTS

90-days ER visit (p=0.244), 90- days readmission (p=0.091), overall complications rate (p=0.376), minor complications (p=0.952) and major complications (p=0.258) were not statistically different between the two groups. Operative time and average LOS were significantly longer in the SBTHA group (p<0.001). Blood loss was significantly higher (p<0.001) in the SBTHA group. However, no difference in the transfusion rate between the two groups was observed (p=0.724).

CONCLUSION

Complication rate, 90- days hospital readmission and 90-days ER visit were similar between the two groups. This study shows that performing SBTHA is a safe, effective, and doesn't carry additional risks for patients with bilateral symptomatic osteoarthritis.

Comparison of postoperative outcomes between bikini-incision via direct anterior approach and posterolateral approach in simultaneous bilateral total hip arthroplasty: a randomized controlled trial

The purpose of this study was to compare an oblique bikini-incision via direct anterior approach (BI-DAA) to a conventional posterolateral approach (PLA) during simultaneous bilateral total hip arthroplasty (simBTHA) in terms of early patient outcomes, postoperative functional recovery, and complications. From January 2017 to January 2020, 106 patients receiving simBTHA were enrolled and randomly allocated to the BI-DAA or PLA group. Primary outcomes were measured using hemoglobin (HGB) drop, transfusion rate, the length of stay (LOS), the visual analog scale (VAS) for pain, the Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index, and the scar cosmesis assessment and rating scale. Secondary outcomes were the operative time, radiographic measurements, including femoral offset, femoral anteversion, stem varus/valgus angle, and leg length discrepancy (LLD). The occurrence of postoperative complications was also recorded. There were no differences in demographic or clinical characteristics before surgery. Compared to the PLA, the patients in the BI-DAA group had lower HGB drop (24.7 ± 13.3 g/L vs. 34.7 ± 16.7, P < .01) and transfusion rates (9/50 vs. 18/50, P = .04) and a shorter LOS (5.12 ± 1.5 vs. 6.40 ± 2.0 days, P < .01) without increasing the operative time (169.7 ± 17.3 vs. 167.5 ± 21.8 min, P = .58). The BI-DAA group yielded a smaller LLD (2.1 ± 2.3 vs. 3.8 ± 3.0 mm, P < .01) and less variability in component orientation than the PLA group (100% vs. 93%, P = .01). As for the scar, the BI-DAA group produced a shorter incision length (9.7 ± 1.6 vs. 10.8 ± 2.0 mm, P < .01) and higher postoperative recovery satisfaction than the PLA group. Furthermore, the BI-DAA group had a reduced VAS score one week after surgery and had better functional recovery in three months postoperatively. The BI-DAA group had a higher incidence of LFCN dysesthesia (12/100 vs. 0/100 thighs, P < .01), while other complications did not differ significantly between the two groups. For simBTHA, the bikini incision offers early recovery, less variance in components orientation, better postoperative outcomes, and scar healing than the PLA. Therefore, the bikini incision could be a safe and feasible option for simBTHA recipients.

Outcomes after bilateral shoulder arthroplasty: a systematic review

The purpose of this systematic review was to report outcomes after bilateral shoulder arthroplasty including bilateral total shoulder arthroplasty (TSA), bilateral reverse shoulder arthroplasty (RSA), and ipsilateral TSA with contralateral RSA (TSA/RSA). Two reviewers independently performed a PRISMA-guided systematic search using MEDLINE/PubMed, Embase, and Cochrane Database of Systematic Reviews up to May 11, 2021. The databases were queried using the following search terms: (["bilateral" OR "contralateral"] AND "shoulder" AND ["arthroplast∗" OR "replacement"]). A total of 486 titles/abstracts were screened for eligibility and 19 studies were included in the final analysis. Risk of bias was assessed using Methodological Index for Nonrandomized Studies and Modified Coleman Methodology scores. Analysis compared overall results for bilateral shoulder arthroplasty and sub-group analyses compared TSA (all shoulders from bilateral TSA patients and the TSA shoulder in TSA/RSA patients) to RSA (all shoulders from bilateral RSA patients and the RSA shoulder in TSA/RSA patients), first shoulder arthroplasty to second contralateral shoulder arthroplasty, and interval between arthroplasty (IBA) <20 months to IBA ≥20 months. Nineteen studies analyzed bilateral TSA (n = 3), bilateral RSA (n = 7), and TSA/RSA (n = 8). The mean Methodological Index for Nonrandomized Studies was 18 and mean Modified Coleman Methodology Score was 74, with 63.2% of studies demonstrating level III evidence. A total of 2729 patients (30.4% male; mean age 72.2 years, mean follow-up 47.3 months, mean IBA 20 months) were analyzed. Postoperative forward flexion (142.0° vs. 129.6°), external rotation (ER) (42.5° vs. 25.6°), and internal rotation (60% reaching T12-T8 vs 85.7% reaching L3-L1) were higher for TSA when compared to RSA. Patient reported outcome measures such as Constant-Murley (73.2 vs. 59.2), American Shoulder and Elbow Surgeons (87.9 vs. 77.7), and Single Assessment Numeric Evaluation (SANE) (86.9 vs. 67.8) were higher for TSA when compared to RSA. Patients with IBA ≥20 months demonstrated greater ER and patient satisfaction than patients with IBA <20 months. Postoperative complication rates were 15.1% for TSA and 10.6% for RSA, while reoperation and revision rates were 13.7% for TSA and 7.1% for RSA. Bilateral shoulder arthroplasty results in improvements in motion, strength, pain, function, and high satisfaction. Bilateral TSA is associated with greater improvement in motion and function than bilateral RSA but higher complication, reoperation, and revision rates. IBA ≥20 months is associated with greater ER and satisfaction than IBA <20 months.

Simultaneous Bilateral Total Hip Arthroplasty with Straight-Stems and Short-Stems: Does the Short One Do a Better Job?

BACKGROUND

Total hip arthroplasty (THA) is known to be the most successful orthopaedic surgery of the last century, but it is still struggling with controversies concerning one-stage bilateral THA. The current study aimed to compare the clinical outcome of patients with unilateral or simultaneous bilateral THA by using short-stem and straight-stem designs and focusing on operation time, blood loss, and length of hospital stay (LOS).

MATERIAL AND METHODS

Between 2006 and 2018, 92 patients were enrolled in this study. Forty-six patients underwent a bilateral THA in one session, and forty-six matched patients underwent a unilateral THA. In each of the two groups (unilateral vs. bilateral), 23 patients received either a straight (unilateral: 10 females, 13 males, mean age 63; bilateral: 12 females, 11 males, mean age 53 years) or short stem (unilateral: 11 females, 12 males, mean age 60 years; bilateral: 12 females, 11 males, 53 mean age 62 years). The blood count was checked preoperatively as well as one and three days after surgery. Furthermore, the operation time and LOS were investigated.

RESULTS

Compared to THA with straight-stems, short-stem THA showed significantly less blood loss; there was no difference in the LOS of both groups. A significantly shorter operative time was only observed in the bilateral THA.

CONCLUSION

The current study showed that simultaneous bilateral THA appears to be safe and reliable in patients without multiple comorbidities. In addition, short-stem THA appears to be beneficial in terms of clinical performance and outcome, and it appears to be superior to straight-stem THA, regardless of whether the patient underwent unilateral or simultaneous bilateral THA.

Perioperative safety assessment of patients undergoing unilateral or bilateral hip replacements

Introduction

Due to the aging of the world population and the increase of obesity rate, it is expected that the number of joint replacement surgery will continue to increase in the next few years. This study evaluated the safety differences between unilateral and bilateral hip replacement surgeries.

Methods

The data for patients who underwent hip arthroplasty in 2021 and 2022 were examined. The data set included 68 patients who were grouped according to the type of hip replacement needed, sex, age, and body mass index. Total blood loss and operative time were the safety-related indicators used to compare the groups.

Results

Regardless of whether the unilateral replacement group was compared with the overall bilateral replacement group or separately with the staged and simultaneous bilateral replacement groups, simultaneous bilateral replacement surgeries were equally safe as the other types of hip replacements. The total blood loss and operative time for the simultaneous bilateral replacement group were not significantly different from those in the unilateral and staged bilateral replacement groups. For overweight patients, the operative time for simultaneous bilateral replacements was significantly shorter than that for unilateral replacements.

Conclusions

These findings suggest that for patients requiring bilateral hip replacements, the blood loss risk for patients undergoing simultaneous bilateral hip replacements was similar to that for patients undergoing either unilateral or staged bilateral hip replacements. Thus, simultaneous bilateral total hip replacement (THR) are safe and should be considered for candidate patients.

The Safety of Bilateral Simultaneous Hip and Knee Arthroplasty versus Staged Arthroplasty in a High-Volume Center Comparing Blood Loss, Peri- and Postoperative Complications, and Early Functional Outcome

Purpose: In recent years, there has been increasing interest in the use of simultaneous hip and knee arthroplasty compared to staged procedures in patients with bilateral pathology. The aim of this study was to compare simultaneous and staged hip and knee arthroplasty in patients with bilateral pathology by assessing the transfusion rate, postoperative hemoglobin drop, length of stay (LOS), in-hospital complications, 30-day readmissions and early functional outcome. Methods: We conducted a retrospective cohort study that included all patients who were undergoing primary TKA, THA and UKA by a single surgeon in a high-volume arthroplasty center between 2015 and 2020 as simultaneous or staged procedures. Staged bilateral arthroplasties were performed within 12 months and were stratified by the time between procedures. Data were acquired through the electronic files at the Orthopädische Chirurgie München (OCM). For functional outcome, the ability of the patients to walk independently on the ward was compared with the ability to walk a set of stairs alone, which was recorded daily by the attending physiotherapist. Results: In total n = 305 patients were assessed for eligibility and included in this study. One hundred and forty-five patients were allocated to the staged arthroplasty group. This group was subdivided into a hip and a knee group, whereas the knee group was split into TKA and UKA. The second staged procedure was performed within 12 months of the first procedure. One hundred and sixty patients were allocated to the simultaneous arthroplasty group. This group was also subdivided into a hip and knee group, whereas the knee group was split again into a TKA and UKA group. No statistical difference was found between the two groups regarding demographic data. Primary outcome measurements: There was no significant difference in the transfusion rate or complication rate. Secondarily, no statistically significant difference was found between the postoperative hemoglobin drop and the functional outcome, or in the length of stay (LOS) between both groups. Walking the stairs showed a significant difference in the knee group. Conclusions: There were no significant differences observed in the transfusion rate in-hospital complications, or readmission rate between both groups. The early functional outcome showed no significant difference in mobility for all groups. Simultaneous arthroplasty for knee or hip is as safe as a staged procedure, with no higher risk for the patient, in a specialized high-volume center. Level of evidence: Level IV.

The Symmetry and Predictive Factors in Two-Stage Bilateral Hip Replacement Procedures

Background: Approximately 10–25% of total hip replacement patients undergo a bilateral procedure. The purpose of this study was to compare selected parameters associated with the first and second hip arthroplasty in patients undergoing two-stage treatment due to bilateral hip osteoarthritis and establish the predictive factors for the second procedure. Methods: This study compared the data on bilateral total hip replacement surgeries conducted in the period between 2017 and 2021 (42 patients). The following parameters from the first and second procedure were compared: the prosthetic stem, head, and insert cup size; type of cup insert; duration of anesthesia; duration of hospitalization; and the number of complications. Results: The mean duration of hospital stay at the time of the first total hip arthroplasty was 5.83 days and 5.4 days during the second stay. The mean stem sizes used during the first and second total hip replacement procedures were 7.11 and 7.09, respectively. The mean sizes of endoprosthetic cups used at the first and second total hip replacement procedures were 52.64 and 53.04, respectively. There were no significant differences between the mean prosthetic head size at the first and second surgery. The cup type used during the first and second surgery showed no difference. The mean duration of anesthesia used during the first and second total hip replacement surgery was 108.09 min and 104.52 min, respectively. We recorded a mean of 0.07 complications per patient at the first surgery and 0.02 at the second surgery. Conclusions: Our study results showed symmetry duration of anesthesia, length of hospital stay, number of complications per patient, stem size, prosthetic head size, cup insert size, and cup insert type at the first and second surgery in patients with two-stage bilateral total hip arthroplasty. We observed a strong correlation between the stem sizes of the first and second hip endoprostheses. There was also a strong correlation between the cup sizes used during the first and second surgery.

Outcomes of simultaneous bilateral total hip arthroplasty for 256 selected patients in a single surgeon's practice

AIMS

Total hip arthroplasty (THA) using the direct anterior approach (DAA) is undertaken with the patient in the supine position, creating an opportunity to replace both hips under one anaesthetic. Few studies have reported simultaneous bilateral DAA-THA. The aim of this study was to characterize a cohort of patients selected for this technique by a single, high-volume arthroplasty surgeon and to investigate their early postoperative clinical outcomes.

METHODS

Using an institutional database, we reviewed 643 patients who underwent bilateral DAA-THA by a single surgeon between 1 January 2010 and 31 December 2018. The demographic characteristics of the 256 patients (39.8%) who underwent simultaneous bilateral DAA-THA were compared with the 387 patients (60.2%) who underwent staged THA during the same period of time. We then reviewed the length of stay, rate of discharge home, 90-day complications, and readmissions for the simultaneous bilateral group.

RESULTS

Patients undergoing simultaneous bilateral DAA-THA had a 3.5% transfusion rate, a 1.8 day mean length of stay, a 98.1% rate of discharge home, and low rates of 90-day infection (0.39%), dislocation (0.39%), periprosthetic fracture (0.77%), venous thromboembolism (0%), haematoma (0.39%), further surgery (0.77%), and readmission (0.77%). These patients were significantly younger (mean 58.2 years vs 62.5 years; p < 0.001), more likely to be male (60.3% vs 46.5%; p < 0.001), and with a trend towards having a lower mean BMI (27.8 kg/m² vs 28.4 kg/m²; p = 0.071) than patients who underwent staged bilateral DAA-THA.

CONCLUSION

Patients selected for simultaneous bilateral DAA-THA in a single surgeon's practice had a 3% rate of postoperative transfusion and a low rate of complications, readmissions, and discharge to a rehabilitation facility. Simultaneous bilateral DAA-THA appears to be a reasonable and safe form of treatment for patients with bilateral symptomatic osteoarthritis of the hip when undertaken by an experienced arthroplasty surgeon with appropriate selection criteria. Cite this article: Bone Joint J 2021;103-B(7 Supple B):116-121.

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.

Are the First or the Second Hips of Staged Bilateral THAs More Similar to Unilateral Procedures? A Study from the Swedish Hip Arthroplasty Register

BACKGROUND

Bilateral THAs performed in the same patient should not be considered independent observations, neither biologically nor statistically. As a result, when surgical results are reviewed, it is common to analyze only the first of the two hips, assuming that the first, and not the second hip of a staged bilateral THA, better resembles unilateral THAs. This assumption has not been empirically justified.Question/purposes (1) In patients with staged bilateral THA, is the first or second hip more similar to a unilateral THA in terms of age at surgery, presence of any preoperative Charlson comorbidity, and risk of postoperative reoperation? (2) Should the date of a first or second hip surgery of a staged bilateral THA be used as a starting point for patient survival to better resemble patients with unilateral THA?

METHODS

We identified 68,357 THAs due to osteoarthritis in 63,613 patients from the Swedish Hip Arthroplasty Register (SHAR) in 1999-2015. Of those THAs, 14,780 concerned the first hip of a staged bilateral procedure performed between 1999 and 2004; 28,542 were unilaterals from 2004 to 2008, and 25,035 concerned the second hip of a staged bilateral procedure performed 2008 to 2015. We excluded patients who underwent one-stage bilateral THAs. We used different inclusion periods to distinguish unilateral procedures from the first and second hips from staged bilateral procedures because sufficiently long set-up and follow-up periods were needed before and after each period to identify possible contralateral THAs. This introduced potential period confounding, meaning that possible group differences might not be distinguished from unrelated outcome differences over time. We investigated if such time trends existed. It did not for age and reoperation rates, but it did for comorbidity and patient survival. Our primary study endpoint was whether patients with unilateral THAs were more similar to patients with a first hip of a staged bilateral THA, or to patients with their second hip operated. We used Student's t-test to compare mean age at surgery. The proportion of patients with at least one presurgery Charlson comorbidity were compared by 95% bootstrap confidence intervals, after subtracting the yearly time-trend to avoid period confounding. Postoperative risks of reoperation were compared by log-rank tests of Kaplan-Meier curves and by comparing 5-year reoperation rates by pair-wise 95% CIs. Our secondary study endpoint was to compare patient survival for patients with a unilateral THA, a first hip of a staged bilateral THA, or a second hip of a staged bilateral THA. We evaluated this by relative 5-year survival, comparing patients of each group with the general Swedish population of the same age, sex, and year of birth. This way, possible survival differences would be less likely explained by period confounding.

RESULTS

Patients undergoing unilateral THA were older than those undergoing a first hip of a staged bilateral THA (70 ± 10 versus 66 ± 9 years, mean difference of 4; p < .001), but they were not different from patients undergoing the second hip of a staged bilateral THA (70 ± 9 years, mean difference of 0; p = 0.74). The period-adjusted proportion of patients with unilateral THA and presurgery comorbidity (Charlson index > 0) was 20% (95% CI: 19.8-20.7). This was no different from patients with a second hip from a staged bilateral THA (20%; 19.7-20.6), but higher compared to patients with a first hip of a staged bilateral THA (15%; 14.5-15.4). For reoperation rates, the log-rank tests showed no difference between unilateral THAs and the second hips of staged bilateral THAs ((Equation is included in full-text article.)). Such difference was found for unilaterals compared with the first hips of staged bilateral THAs ((Equation is included in full-text article.)). The Kaplan-Meier estimate of reoperation rates at 5 years after surgery were also no different for the unilateral THAs compared with the second hips of staged bilateral THAs (3% [95% CI 2.8 to 3.2] for both groups). It was lower (2% [95% CI 1.8 to 2.3]) for a first hip of a staged bilateral THA. For the secondary outcome, the relative 5-year survival differed for all groups. It was 105% (95% CI 104.9 to 105.9) for patients with unilateral THA, 107% (95% CI 106.3 to 107.4) for patients with a second hip from a staged bilateral THA and 109% (95% CI 108.8 to 109.5) for patients with a first hip of a staged bilateral THA. Patients with only a first hip of a planned staged bilateral THA who did not survive long enough to undergo their second THA were classified as unilaterals. The rank-order of survival curves are therefore by design ("immortal time bias"). We conclude, however, that survival for patients with unilateral THA more closely resembles the survival of patients with a second hip of a staged bilateral THA, compared with the first.

CONCLUSIONS

Our findings, which are based on observational register data, challenge the common practice in epidemiologic studies of analyzing only the first hip of a staged bilateral THA. We recommend analyzing the second THA in a patient who has undergone staged bilateral THA rather than the first because the second procedure better resembles unilateral THA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Factors Affecting Discharge Disposition After Primary Simultaneous Bilateral Joint Arthroplasty

BACKGROUND

Predicting discharge destination following total joint arthroplasty (TJA) is important, as discharge destination has major implications for post-operative costs, clinical outcomes, and readmissions. Few studies have looked at factors affecting discharge destination for patients following primary simultaneous bilateral total joint arthroplasty.

QUESTIONS/PURPOSES

The purpose of this study was to describe clinical and social factors that relate to a discharge to home versus rehabilitation facility (RF) for patients after primary simultaneous bilateral total hip arthroplasty (PSBTHA) or primary simultaneous bilateral total knee arthroplasty (PSBTKA).

METHODS

The inclusion criteria for this retrospective cohort study were all patients after PSBTHA or PSBTKA at a metropolitan orthopedic specialty hospital between February 1, 2016, and March 31, 2018. Exclusion criteria were revisions, differing weight-bearing status, bed-rest orders, and non-standard hip precautions. Social and clinical demographic data were collected. Multiple regression analysis was conducted to determine which factors related most to discharge plan.

RESULTS

Of 253 PSBTHA patients, 153 were discharged home and 100 to an RF. Regression analysis found a posterolateral approach to be the only significant factor associated with an RF discharge. Of 619 PSBTKA patients, 136 were discharged home and 483 to RF. Increased body mass index and older age increased the likelihood of discharge to an RF. Patients with an adductor-only nerve block were more likely to be sent to RF.

CONCLUSION

These findings shed light on the variables that contribute to discharge destination after PSBTHA and PSBTKA. Such information allows for safe pre-operative discharge planning and assists with discharge to the appropriate level of patient care. Future studies might investigate the effect of surgeon experience, surgical technique, and pre-operative discussion with a physical therapist on the discharge disposition of patients undergoing bilateral total joint arthroplasty.