Safety and outcome of simultaneous bilateral unicompartmental knee arthroplasty: A systematic review

A comparative study of single-stage bilateral vs. unilateral medial unicompartmental knee arthroplasty on complications, clinical outcomes, and costs

Background

This retrospective study aimed to evaluate the short-term recovery and cost-effectiveness of bilateral unicompartmental knee arthroplasty (UKA) compared to staged unilateral UKA. The study analyzed postoperative pain scores, medical costs, and complications in patients with knee osteoarthritis who underwent these procedures.

Methods

A total of 226 patients who received either unilateral UKA (Group A, n = 170) or bilateral UKA (Group B, n = 56) using the mobile-bearing UKA were included in the study. Patient demographics, surgical details, postoperative pain scores, knee range of motion, length of hospital stay, self-controlled analgesic use, total medical costs, and complications were retrospectively collected from medical records.

Results

The demographic characteristics were comparable between the groups. Group B had a longer surgical time and higher medical costs than Group A. However, there were no significant differences in hospital stay, pain scores, or knee range of motion between the two groups. Complications were infrequent and not significantly different. Insert dislocation and loosening were the most common complications. Patient-controlled analgesia effectively reduced pain scores in Group A but not in Group B.

Conclusion

Bilateral UKA does not significantly affect hospital stay, postoperative pain, or complications compared to unilateral UKA. Although bilateral UKA requires longer surgical time and incurs higher costs, it offers the potential benefit of reducing anesthesia-related complications and overall health insurance expenditures. This study recommends bilateral UKA as a suitable option for patients with bilateral knee osteoarthritis, given its comparable short-term outcomes and potential cost-saving advantages.

Level of Evidence

III.

Effect of body mass index on 30-day complication rate and implant survival rate after simultaneous bilateral unicompartmental knee arthroplasty: a multicentre retrospective study

OBJECTIVE

The practice of simultaneous bilateral unicompartmental knee arthroplasty (SBUKA) remains a topic of debate, particularly in patients with obesity. Thus, the purpose of this study was to assess the impact of body mass index (BMI) on the 30-day complication rate and the survival rate of the implant following SBUKA.

METHODS

We retrospectively examined the clinical records of 245 patients (490 knees) who underwent SBUKA at the Affiliated Hospital of Qingdao University and the Third Hospital of Hebei Medical University between January 2010 and December 2020. Patients were categorised based on their BMI at the time of surgery into four groups: normal weight (BMI 18.5 to 22.9 kg/m2), overweight (BMI 23.0 to 24.9 kg/m2), obese (BMI 25.0 to 29.9 kg/m2), and severely obese (BMI ≥30 kg/m2). Variables such as length of hospital stay, duration of surgery, and costs of hospitalisation were compared across all groups. Additionally, we recorded the 30-day postoperative complication rate and the time from surgery to any required revision. The Kaplan-Meier survival analysis was employed to evaluate and compare the implant survival rates.

RESULTS

The follow-up period for the 245 patients ranged from 39 to 114 months, with an average of 77.05±18.71 months. The incidence of complications within 30 days post-surgery did not significantly differ across the groups (χ2 = 1.102, p = 0.777). The implant survival rates from the lowest to the highest BMI groups were 97.14%, 93.9%, 94.44%, and 96.43%, respectively. Both the rate of implant revision (χ2 =1.612, p = 0.657) and the survival curves of the implants (p = 0.639) showed no statistically significant differences among the groups.

CONCLUSIONS

BMI did not influence the 30-day complication rate nor the survival rate of implants following SBUKA, suggesting that SBUKA should not be contraindicated based on BMI alone.

Advantages of Simultaneous Cementless Bilateral Unicondylar Knee Arthroplasty Compared to Staged Surgery

Background

Unicondylar knee arthroplasty (UKA) is an effective procedure, which reduces pain, increases range of motion, and improves function. UKA could be performed simultaneously or in staged sessions. This study aimed to compare bilateral cementless UKA performed simultaneously and in staged sessions in terms of complications, hemoglobin levels, transfusions, and functional outcomes.

Methods

Patients undergoing bilateral UKA for symptomatic medial compartment osteoarthritis were retrospectively analyzed. Of the 73 patients who met the inclusion criteria, 40 underwent surgery simultaneously and 33 underwent surgery in separate sessions. Operative time, length of hospital stay, change in hemoglobin, need for blood transfusion, complications, and functional outcomes were assessed.

Results

There was no statistically significant difference between the two groups in demographic data. Simultaneously operated patients had a significantly shorter hospital stay and shorter operative time. Statistically significant improvements in clinical scores were noted in both groups. The degree of improvement in functional scores did not differ between the groups. There was no difference between the two groups in terms of complication rates, but the number of periprosthetic tibial fractures was higher in the simultaneous group.

Conclusions

Simultaneous bilateral cementless UKA was more advantageous in terms of cumulative hospital stay and total operation time with similar clinical results when compared to a staged procedure. While the overall complication rate was similar, the rate of periprosthetic fractures was 5% in the simultaneous group.

Cementless versus cemented unicompartmental knee arthroplasty: a systematic review of comparative studies

There are still some controversies regarding the clinical use of cementless UKAs. The aim of this systematic review was to determine whether cementless medial UKA leads to similar outcomes compared to cemented medial UKA. This search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews guidelines (PRISMA). The random effects model with 95% confidence interval (CI) was applied to the analysis. The I2 statistic was used to assess study heterogeneity. Six studies were eligible for inclusion (4784 UKAs, 4776 patients): 2947 cemented UKAs (61.6%) and 1837 cementless UKAs (38.4%). The overall mean follow-up was 4.9 years. The all-cause reoperation rate was 11.3% (80 of 706) at mean 5.7-year follow-up for cemented UKA and 6.9% (57 of 824) at mean 4.1-year follow-up for the cementless. The overall revision rate was 10.2% (303 of 2947) for the cemented and 5.8% (108 of 1837) for the cementless. Aseptic loosening was the most frequent reason of revision (2.3% cemented vs 0.5% cementless). The overall rate of radiolucent lines (RLL) was 28.3% (63 of 223) in the cemented cohort and 11.1% in the cementless (26 of 234). All the studies reported improved functional outcomes. Cementless UKA provides at least equivalent if not better results compared to cemented UKA. Despite the use of cemented UKA outnumber cementless fixation, available data shows that cementless UKA had a reduced midterm revision rate, while providing similar functional outcomes.

Can single-stage bilateral unicompartmental knee arthroplasty be safely performed in patients over 70?

Background

For patients with bilateral, symptomatic unicompartmental knee arthritis, single-stage bilateral unicompartmental knee arthroplasty (ssBUKA) presents an attractive option. However, most studies have examined younger patient cohorts and the safety of ssBUKA remains controversial for older individuals. Therefore, the purpose of this study was to compare complication rates following ssBUKA for patients ≤70 and > 70 years old.

Methods

A retrospective chart review of 238 patients having undergone ssBUKA was performed, including 134 patients ≤70 and 104 patients >70. Post-operative complications were recorded at the six-week post-operative visit, along with emergency room visits and hospital readmissions within 90 days.

Results

Compared to patients ≤70, patients >70 were more frequently female (43.3% and 55.8%, respectively) (p = 0.037) and had significantly lower body mass index (30.41 ± 4.64 and 27.30 ± 3.68, respectively) (p < 0.001). Patients >70 were discharged home (50%) less commonly than patients ≤70 (73.1%) (p < 0.001). Two patients ≤70 (1.5%) and two patients >70 (1.9%) sought emergency room treatment (p = 0.589), with respiratory complications most common. There were no differences regarding any postoperative complications between patients ≤70 and > 70 years old.

Conclusion

These results suggest that patients >70 can safely undergo ssBUKA, as it does not appear to increase the incidence of early post-operative complications compared to patients ≤70. However, 50% of patients >70 were not able to discharge directly home following surgery.

No difference between mobile and fixed bearing in primary total knee arthroplasty: a meta-analysis

PURPOSE

Both mobile (MB) and fixed (FB) bearing implants are routinely used for total knee arthroplasty (TKA). This meta-analysis compared MB versus FB for TKA in terms of implant positioning, joint function, patient reported outcome measures (PROMs), and complications. It was hypothesised that MB performs better than FB implants in primary TKA.

METHODS

This meta-analysis was conducted according to the 2020 PRISMA statement. In February 2022, the following databases were accessed: Pubmed, Web of Science, Google Scholar, Embase. All the randomized clinical trials (RCTs) comparing mobile versus fixed bearing for primary TKA were considered.

RESULTS

Data from 74 RCTs (11,116 procedures) were retrieved. The mean follow-up was 58.8 (7.5 to 315.6) months. The MB group demonstrated greater range of motion (ROM) (P = 0.02), Knee Society Score (KSS) score (P < 0.0001), and rate of deep infections (P = 0.02). No difference was found in implant positioning: tibial slope, delta angle, alpha femoral component angle, gamma femoral component angle, beta tibial component angle, tibiofemoral alignment angle, posterior condylar offset, radiolucent lines. No difference was found in duration of the surgical procedure. No difference was found in the following PROMs: Oxford Knee Score (OKS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analogue scale (VAS), function and pain subscales of the KSS score. No difference was found in the rate of anterior knee pain, revision, aseptic loosening, fractures, and deep vein thrombosis.

CONCLUSION

There is no evidence in support that MB implants promote greater outcomes compared to FB implants in primary TKA.

LEVEL OF EVIDENCE

Level I.

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.