Enhanced recovery after surgery day surgery for MAKO® robotic-arm assisted TKA; better outcome for patients, improved efficiency for hospitals.

Introduction: Robotic-assisted Total Knee Arthroplasty (TKA) was designed to improve implant position accuracy by providing surgeons with real-time intra-operative data to tailor the operation to the patient. Proponents of robotic-assisted TKA believe that this translates into meaningful improvements in outcomes. However, there are concerns that the longer surgical duration associated with robotic-assisted TKA leads to longer length of stay (LOS). In this study, the authors investigated the outcome of MAKO® Robotic-arm Assisted TKA combined with ERAS protocol to assess its effect on LOS and short-term outcomes. Methods: All patients who had undergone unilateral MAKO® ERAS Day Surgery TKA from August 2020 to July 2021 were prospectively followed up and matched to patients who underwent conventional ERAS Day Surgery TKA in the same time period. Factors such as surgical duration, LOS, immediate reduction in pain, 30-days complications, and 6-month PROMs and knee ROM were compared between the two groups. Results: 42 patients underwent MAKO® ERAS Day surgery TKA and were matched to 42 patients who underwent conventional ERAS Day surgery TKA. The study found that despite the longer surgical duration, LOS was comparable between both groups (1.1 ± 0.9days in the MAKO® group vs 1.0 ± 0.3days in the conventional group, p = 0.755) with successful 24-hour discharge in 88.1 % of patients in the MAKO® group. The MAKO® group achieved significantly better ROM compared to the conventional group 6-months post operatively. Post-operative PROMs were comparable between both groups. Conclusion: ERAS Day Surgery protocol can significantly reduce the LOS of patient undergoing MAKO® Robotic-arm Assisted TKA, conferring cost savings and making it a valid option for patients.

Unicompartmental knee arthroplasty in obese patients, poorer survivorship at 15 years.

Introduction: The preclusion of obese patients from unicompartmental knee arthroplasty (UKA) has increasingly been challenged. This study aimed to evaluate the impact of Body Mass Index (BMI) on UKA at 15-year follow-up. Materials and methods: 169 unilateral UKA patients from 2003 to 2007 were followed-up prospectively for at least 15 years. 70 patients were left for analysis after accounting for patient demise, revision surgery and loss to follow-up. 48 of these patients (69%) were in the Control group (BMI <30 kg/m2) and 22 (31%) were in the Obese group (BMI ≥30 kg/m2). Patients were assessed before and after operation using the Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), Oxford Knee Score (OKS), and Physical (PCS) and Mental (MCS) component of the Short Form 12. Survivorship analysis was also performed. Results: Obese patients went through UKA at an earlier age than the non-obese patients (54.7 ± 4.7 years compared to 59.9 ± 7.8 years, p = 0.005). At 2, 10, and 15-year follow-up, both groups achieved clinically significant improvements in outcomes. There was no significant association found between obesity and outcome using multiple linear regression. While propensity matching found PCS improvement at 2 years to be greater in obese patients, no significant association between obesity and 15-year outcome was found. All 13 patients who required revision, underwent total knee arthroplasty (TKA). The overall 15-year survivorship was 74.2% within the obese group and 92.4% within the control group. Conclusion: Compared to non-obese patients, obese patients had poorer 15-year survivorship with greater odds of requiring revision surgery. However, assuming implant survival, obese patients can expect a non-inferior outcome relative to their non-obese counterparts in all patient reported outcome measures 15 years after surgery.

Postponement of total knee arthroplasties due to pandemic causes significant deterioration on patients' preoperative knee and quality of life scores.

Introduction: Elective surgeries were postponed during the COVID-19 pandemic to alleviate healthcare strains, affecting majority of elective orthopaedic surgeries such as total knee arthroplasties (TKAs). The aim of this study is to evaluate the impact on knee function and quality of life of patients who had their planned TKA postponed due to the pandemic. Methods: This is a retrospective analysis of data collected in a tertiary hospital. Patients included were diagnosed with primary knee osteoarthritis and they were initially scheduled for primary TKA between January to April 2020 but surgery was postponed by at least 6 months from the initial operative date. 160 patients were included in this study (53 males and 107 females, mean age 68.0 ± 8.1). Patients were assessed prior to initial surgery date and assessed again, prior to the postponed surgery date. Clinical scores included Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), Oxford Knee scores (OKS) and Short-Form 36 Physical and Mental Component Scores. (SF36 PCS and MCS). Paired T-test was performed for parametric data whereas Wilcoxon signed-rank analysis was performed for non-parametric data. Results: Comparing initial preoperative versus postponement preoperative scores, the cohort had significantly poorer KSKS (38.4 ± 15.4 and 36.5 ± 15.4, p = 0.034), SF36 PCS (34.3 ± 9.2 and 32.7 ± 8.6, p = 0.02) and OKS (34.9 ± 0.77 and 35.8 ± 8.6, p = 0.02) scores respectively. Conclusion: The postponement of elective TKAs has resulted in a significant deterioration of knee scores and physical quality of live scores of patients in a short span of 6 months. Further studies can evaluate if there are repercussions on long term TKAs outcomes. Level of evidence: Retrospective study, Level III.

Severe genu varus deformity does not affect enhanced recovery after surgery total knee arthroplasty outcomes.

INTRODUCTION: Enhanced recovery after surgery (ERAS) has been increasingly adopted in orthopaedic surgery. Although not an exclusion criterion, patients undergoing total knee arthroplasty (TKA) with preoperative severe varus deformity may be less likely to be enrolled for ERAS. This study aimed to compare the success of ERAS TKA between patients with severe preoperative varus deformities (≥ 15° varus) and the control group (< 15° varus to 14° valgus). Our secondary aim was to compare postoperative complications and functional outcomes between the two groups. MATERIALS & METHODS: 310 TKAs performed from August 2019 to February 2021 were analyzed with a follow-up of 6 months postoperatively. The primary outcome, ERAS TKA success, was defined as length of hospital stay of < 24 h. Other parameters included 30-day postoperative complications and clinical outcomes such as the original Oxford Knee Score (OKS), the Knee Society Knee (KSKS) and Function Score (KSFS), Visual Analog Scale for Pain (VAS-P), 36-Item Short-Form Health Survey (SF-36) Physical Component Summary (PCS) and SF-36 Mental Component Summary (MCS). RESULTS: There were 119 patients in the severe deformity group and 191 patients in the control group. There were no significant differences in ERAS success between the severe deformity group and control group, with both groups achieving similarly high rates (> 90%) of ERAS success. There were also no differences in 30-day postoperative complications and 6-month postoperative clinical outcomes. CONCLUSION: Patients with severe preoperative varus deformity undergoing ERAS TKA achieved high ERAS success rates (> 90%). Genu varum is not a contraindication for ERAS TKA.

Functional outcome of direct anterior versus posterior approach in total hip arthroplasty: a propensity-matched Asian study.

INTRODUCTION: The direct anterior approach (DAA) to total hip arthroplasty (THA) is a surgical approach that minimises soft tissue trauma, resulting in faster rehabilitation when compared to a posterior approach (PA). This study aimed to evaluate the difference between the two groups in an Asian cohort using propensity score matching. METHODS: A retrospective review of prospectively collected registry data of 794 primary THAs was performed. The effects on patients with DAA THA versus patients with PA THA were investigated. Propensity scores were generated using logistic regression to adjust for confounding variables of age, gender, body mass index and diagnosis. Data analysis was performed, and statistical significance was defined as a P value < 0.05. RESULTS: The average length of stay (LOS) for the PA group and DAA group was 5.4 days and 2.9 days, respectively (P < 0.001). One (1.9%) patient from the PA group suffered a posterior dislocation 6 months after surgery and subsequently underwent revision surgery 2 years later. No dislocations were detected in the DAA group. The DAA group had better functional outcome, satisfaction and expectation scores at 6 months and 2 years. CONCLUSION: In this study, patients who underwent DAA THA had better functional outcome at 2 years and almost 2 days shorter overall LOS than those who underwent PA THA. Therefore, the DAA to THA is a novel technique that has shown improved functional outcomes, with fewer complications compared to PA THA.

Enhanced recovery after surgery (ERAS) protocol reduces need for patient selection for day surgery total knee arthroplasty.

Introduction: This study explored the safety and efficacy of Enhanced Recovery After Surgery (ERAS) together with a Day-surgery protocol on some commonly used selection criteria for expedited discharge after Total Knee Arthroplasty (TKA). Methods: ERAS Day surgery TKA performed between Aug 2020 to July 2021 were included in this study. Discharge within 24 h was considered passing protocol. Complications such as infection, re-admission, and re-operation within 30-days were recorded. Patient demographics, medical comorbidities, and outcome measures at 6-month post-operatively were analysed between those who were successfully discharged within 24 h and those with prolong admission. Results: A total of 342 patients were included in the study. 315 patients (92.1 %) were discharged within 24 h s. Inadequately controlled pain was the most common reason for delayed discharge (17.9 %). No statistically significant difference in gender, age, Charlson Comorbidity Index (CCI), Body Mass Index (BMI), and American Society of Anaesthesiologist Classification (ASA) were noted between patients who failed protocol and those who passed. Readmission rate within 30days was 2.6 %. Infection occurred in 5 cases, including 2 prosthetic joint infection (PJI) requiring debridement, antibiotics, and implant retention (DAIR), 2 surgical site infection treated with antibiotics, and 1 pneumonia. No 30-days complication occurred in patients who initially failed ERAS Day-surgery protocol. Binary logistic regression was statistically insignificant on effect of gender, age, CCI, BMI, and ASA on passing protocol or 30-days complications. Propensity score matching of patients with prolong stay of more than 24 h did not demonstrate any difference in 6-month outcome. Conclusion: Patient characteristics such as gender, age, CCI, BMI, and ASA did not influence successful completion of ERAS Day-surgery protocol. Even if patients were initially enrolled in ERAS Day-surgery protocol but failed to be discharged within 24 h, this did not predispose them to increased 30-days complication or poorer 6-month outcome. Level of evidence: III.

Enhanced recovery after day surgery total knee arthroplasty, the new standard of care: An Asian perspective.

BACKGROUND: This study describes the implementation of Enhanced Recovery After Surgery (ERAS) total knee arthroplasty (TKA) with day-surgery protocol to assess the outcome of ERAS day surgery TKA compared with traditional ERAS inpatient TKA in terms of length of stay (LOS), 30-day readmission, complications, and patient-reported outcome measures (PROMs). METHODS: Patients who underwent unilateral primary TKA from August 2020 to July 2021 were followed up. All TKAs were performed with the ERAS protocol. Patients who fulfilled the following inclusion criteria were offered day-surgery protocol: (1) ASA ≤ 3; (2) agreeable for discharge home. In addition, this day-surgery protocol comprised the following: (i) on-call physiotherapy review; (ii) home visit by physiotherapist at 1 week postoperative; (iii) home visit by nurse at 2 weeks postoperative. Day surgery was defined as discharge within 24 h. Patients were followed up for 6 months and PROMs, postoperative complications, and re-admissions recorded. RESULTS: A total of 738 patients were included (342 ERAS day surgery, 396 ERAS inpatient). 92.4% of patients in the day-surgery group were successfully discharged within 24 h, leading to a shorter mean LOS of 1.13 days compared with 4.12 days in the inpatient group (P < 0.005). Both groups achieved significant and comparable improvement in Knee Society Score, Oxford Knee Score, and Physical and Mental component of Short Form-36. Both groups had similar rate of 30-day readmission and complications. CONCLUSION: Patients who underwent ERAS day surgery TKA achieved similar functional and quality of life improvement compared with ERAS inpatient TKA with no increased complication rate. ERAS day surgery TKA is safe and cost effective, and its use should be promoted.

Novel morphogenic knee implant delivers comparable mid-term outcomes as compared to conventional non-morphogenic implants.

INTRODUCTION: Conventional total knee arthroplasty (C-TKA) implants have well-established mid- and long-term outcomes. The novel TKA (N-TKA) implants provide morphogenic implant components with smaller size increments to facilitate anatomical replication. The aim of the study is to evaluate if these advantages provides better clinical outcomes. MATERIALS AND METHODS: Registry data prospectively collected within a single institution from 2014 to 2018 was reviewed and propensity score matching was performed to match C-TKA to N-TKA. 70 pairs of cruciate retaining (CR) TKA and 116 pairs of posterior stabilized (PS) TKA were identified. Range of motion, SF-36, Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS) and Oxford Knee Score (OKS) were assessed preoperatively, 6 and 24 months postoperatively. Satisfaction was assessed 6 and 24 months postoperatively. Independent T test was performed for parametric data, whereas Wilcoxon rank-sum analysis was performed for non-parametric data. RESULTS: Both C-TKA and N-TKA cohorts demonstrated statistically significant improvement for KSKS, KSFS, OKS and SF-36 at 6 and 24 months postoperatively. C-TKA CR patients had better flexion at 6 months as compared to N-TKA CR (108.7° versus 98.3°, respectively, p = 0.046). At 24 months, there was no difference between C-TKA and N-TKA for range of motion, KSKS, KSFS, OKS and SF-36 PCS, regardless of insert type (p > 0.05). CONCLUSIONS: Both models showed great postoperative improvements in KSFS, KSKS, OKS and SF-36 and have comparable early and mid-term outcomes, suggesting that N-TKAs are suitable substitutes for C-TKA. Longer follow-up studies are required to evaluate the long-term outcomes of N-TKAs. LEVEL OF EVIDENCE: lll.

Telescoping Allograft Prosthetic Composite (APC) Reconstruction of the Femur Following Revision Arthroplasty for Neglected Developmental Dysplasia of the Hip (DDH).

Although uncommon, neglected developmental dysplasia of the hip (DDH) poses a technically demanding problem for treating surgeons. Due to the congenital malformation of the native hip joint and distortion of the surrounding soft tissue, addressing limb-length discrepancy is intricate. Despite detailed planning and meticulous soft tissue handling, complications can be difficult to avoid in these patients even under experienced hands. In this case report, we present a 73-year-old lady with neglected DDH who had undergone initial total hip arthroplasty and subsequent revision surgery that failed due to aseptic loosening. Due to limited length in the distal femur, we used a telescoping allograft prosthetic composite (APC) to provide adequate length to the native distal femur during revision with proximal femur fixation. This technique can help avoid the need for total femur replacement (TFR) surgery, which is more invasive and may require tibia replacement.

Long-Term Outcomes of Articular Surface Replacement (ASR) Implant in Hip Arthroplasty: A Single Institution Review.

Various metal-on-metal (MoM) total hip replacements (THRs) have been found to have high short-term failure rates due to adverse responses to metal debris (ARMD). As a consequence, several low-performing THRs have been removed off the market. The purpose of this research was to look at the at least five-year outcomes of patients who had MoM hip arthroplasty at our institution. In one specialised centre between 2007 and 2008, 24 Articular Surface Replacement (ASRTM, DePuy, Warsaw, IN, USA) MoM THRs (in 24 patients, mean age: 56.4 years) were implanted. DePuy ASR hip prosthesis for osteoarthritis or hip fractures were employed in the THR system. All patients were summoned back for a clinical assessment, and imaging was done as needed. The average period of follow-up was 8.0 years (6.0-10 years). In all, eight instances (33.3%) were discovered to have pseudotumors, four hips (16.7%) were revised, and one (4.1%) was operated for ARMD. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Oxford ratings improved statistically significantly five years after surgery in all three areas of pain, disability, and stiffness; however, there was no statistically significant change in the 36-Item Short Form Survey (SF-36) (mental) score. MoM hip arthroplasty had a greater revision incidence at five years in our group, presumably owing to the adoption of a smaller femoral head size.

Clinical Frailty Scale is a better predictor for adverse post-operative complications and functional outcomes than Modified Frailty Index and Charlson Comorbidity Index after total knee arthroplasty.

PURPOSE: Studies have demonstrated correlations between frailty and comorbidity scores with adverse outcomes in total knee replacement (TKR). However, there is a lack of consensus on the most suitable pre-operative assessment tool. This study aims to compare Clinical Frailty Scale (CFS), Modified Frailty Index (MFI), and Charlson Comorbidity Index (CCI) in predicting adverse post-operative complications and functional outcomes following a unilateral TKR. METHODS: In total, 811 unilateral TKR patients from a tertiary hospital were identified. Pre-operative variables were age, gender, body mass index (BMI), American Society of Anesthesiologists (ASA) class, CFS, MFI, and CCI. Binary logistic regression analysis was performed to ascertain odd ratios of pre-operative variables on adverse post-operative complications (length of stay < LOS >, complications, ICU/HD admission, discharge location, 30-day readmission, 2-year reoperation). Multiple linear regression analyses were used to estimate the standardized effects of pre-operative variables on the Knee Society Functional Score (KSFS), Knee Society Knee Score (KSKS), Oxford Knee Score (OKS), and 36-Item Short Form Survey (SF-36). RESULTS: CFS is a strong predictor for LOS (OR 1.876, p < 0.001), complications (OR 1.83-4.97, p < 0.05), discharge location (OR 1.84, p < 0.001), and 2-year reoperation rate (OR 1.98, p < .001). ASA and MFI were predictors for ICU/HD admission (OR:4.04, p = 0.002; OR 1.58, p = 0.022, respectively). None of the scores was predictive for 30-day readmission. A higher CFS was associated with a worse outcome for 6-month KSS, 2-year KSS, 6-month OKS, 2-year OKS, and 6-month SF-36. CONCLUSION: CFS is a superior predictor for post-operative complications and functional outcomes than MFI and CCI in unilateral TKR patients. This suggests the importance of assessing pre-operative functional status when planning for TKR. LEVEL OF EVIDENCE: Diagnostic, II.

Cost-Effectiveness of Robot-Assisted Total Knee Arthroplasty: A Markov Decision Analysis.

BACKGROUND: Robot-assisted total knee arthroplasty (rTKA) may improve clinical outcomes for patients who have end-stage osteoarthritis of the knee. However, the costs of rTKA are high, and there is a paucity of data evaluating the cost-effectiveness of rTKA. We aimed to analyze the cost per quality-adjusted life-year (QALY) of rTKA relative to manual TKA. METHODS: A Markov decision analysis was performed using known parameters for costs, outcomes, implant survivorships, and mortalities. The cost-effectiveness of rTKA relative to manual TKA was assessed for end-stage knee osteoarthritis patients who had a mean age of 65 years (range, 27 to 94 years). The rTKA costs were calculated for a pay-per-use contract robot. RESULTS: Using the Markov Model with an annual case volume of 500 patients and a mean age of 65 years, the overall health gain per patient was 13.34 QALYs after rTKA and 13.31 QALYs after manual TKA. This resulted in an overall gain in QALYs of 0.03 for each patient undergoing an rTKA compared with manual TKA and an incremental cost of $128,526 Singapore Dollars per QALY. CONCLUSION: Robotic TKA is not a cost-effective alternative to conventional TKA using a pay-per-use contract robot.

The effect of topical tranexamic acid on functional outcomes and quality of life in patients undergoing unicompartmental knee arthroplasty.

INTRODUCTION: Tranexamic acid (TXA) is being increasingly utilized to reduce blood loss after knee joint arthroplasty. However, there is a lack of studies on the effect of topical TXA on the functional outcomes and quality of life after Unicompartmental Knee Arthroplasty (UKA). The aim of this study was to determine the effect of topical TXA on functional outcomes and quality of life scores in patients undergoing UKA. MATERIALS AND METHODS: We retrospectively analysed patients undergoing unilateral UKA at a single tertiary hospital from 2005 to 2017. Patients were divided into 2 groups: (1) The control group which did not receive TXA (n = 742); (2) The TXA group which received topical TXA (n = 331). Functional outcomes were assessed using the Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS) and Oxford Knee Score (OKS), while quality of life was evaluated with the Physical Component Score (PCS) and Mental Component Score (MCS) of Short-Form 36 (SF-36) preoperatively and at 6 months and 2 years follow-up. RESULTS: At 6 months and 2 years post-surgery, there were no significant differences in the functional scores between the groups. The number of patients who attained minimum clinically important difference (MCID) for each of the functional scores was also comparable between the groups. CONCLUSIONS: In patients undergoing UKA, functional outcomes and quality of life scores were comparable between those who received topical TXA and those who did not. There was no significant improvement or impairment in knee function associated with topical TXA administration in UKA up to 2 years follow-up.

Preoperative mental distress is associated with poorer physical improvements after revision total hip arthroplasty.

Aims: Despite the increasing prevalence of mental health disorders in revision arthroplasty patients, the impact of preoperative mental distress on functional outcomes after revision total hip arthroplasty (rTHA) remains unclear. Our study aims to investigate the impact of preoperative mental distress on functional outcomes after rTHA. Methods: Prospectively collected data of 84 rTHAs was extracted from a single institution's joint replacement registry. Preoperative Short Form-36 (SF-36) mental component summary (MCS) was used to dichotomize patients to those who were distressed (MCS <50) and non-distressed (MCS ≥50). Multivariable analysis was used to analyze the impact of preoperative mental distress on various outcomes such as the SF-36 physical component summary (PCS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford Hip Score (OHS), patient satisfaction and expectation fulfilment at 6 months and 2 years postoperatively. Results: Compared to non-distressed patients, patients with preoperative mental distress had poorer improvements in PCS (+11.4 vs + 16.9, p = 0.007) and lower rates of minimal clinically important difference (MCID) attainment (55.2% vs 73.0%, p = 0.026) at 2 years postoperatively. However, there were no significant differences in improvements for WOMAC and OHS (p > 0.05). Despite experiencing greater absolute improvements in MCS (+12.1 vs -2.1, p < 0.001) and higher MCID attainment rates (65.5% vs 24.3%, p = 0.005) at 2 years, preoperatively distressed patients had lower MCS levels compared to their non-distressed counterparts at all time points (p-value<0.05). There were no significant differences in patient satisfaction (p = 0.509) or expectation fulfilment (p-value = 0.342) at 2 years postoperatively. Conclusion: Revision THA led to substantial mental health improvements in patients with preoperative mental distress. Despite this, preoperative mental distress was associated with poorer physical improvements after surgery.

Revision total hip arthroplasty is associated with poorer clinically meaningful improvements and patient satisfaction compared to primary total hip arthroplasty.

PURPOSE: This study aims to compare PROM improvements and satisfaction rates between revision (rTHA) and primary total hip arthroplasty (pTHA). METHODS: 84 rTHAs were propensity-score matched to 168 pTHAs using patient demographics and preoperative PROMs. Multiple regression was used to evaluate differences in PROMs, minimal clinically important difference (MCID) attainment and patient satisfaction. RESULTS: Compared to pTHA patients, rTHA patients had poorer MCID attainment for OHS, WOMAC and SF-36 PCS and lower satisfaction rates at 2-years postoperatively (p < 0.05). CONCLUSION: Patients undergoing rTHA are likely to have poorer outcomes and should be appropriately counselled to better manage their preoperative expectations. LEVEL OF EVIDENCE: Level II.

Improving Acetabular Component Positioning in Supine Direct Anterior Total Hip Arthroplasty with a Transparency Template: A Novel, Simple, and Cost-effective Technique.

PURPOSE: A novel and simple method to ensure accurate acetabular component anteversion and inclination intraoperatively with the use of a transparency template is described. MATERIALS AND METHODS: Patients who underwent total hip arthroplasty (THA) via direct anterior approach (DAA) from June 2019 to January 2020 were included. A transparency template that can be placed over the image intensifier monitor to allow surgeons an accurate reading of the acetabular component position intraoperatively was designed, developed and utilized to determine effectiveness. The first template consists of two perpendicular lines indicating the "trans-ischial line" and the "pubic symphysis/coccyx". The second template consist of a line indicating 45° inclination and parallel lines of corresponding distances apart required to achieve 20° anteversion based on Lewinnek's formula: version=sin-1 (D1/D2), where D1: minor axis and D2: major axis of the component. This template was used throughout the acetabular part of the surgery, from reaming to impaction of component. Postoperative acetabular inclination, anteversion, surgical duration, length of stay, as well as complications were recorded. RESULTS: Twenty-six patients were included in this study. Mean postoperative acetabular cup inclination was 43.46±3.09° and mean version was 19.98±2.89°. A total of 21 patients (80.8%) fell within the Callanan safe zone and all 26 patients (100%) were within the Lewinnek safe zone. CONCLUSION: The transparency template is a simple, reproducible, and effective tool with a minimal learning curve and no requirement for expensive equipment. This template has the potential to assist surgeons, especially those who are less experienced with DAA THA, in obtaining better postoperative radiographic outcomes.

Similar postoperative outcomes after total knee arthroplasty with measured resection and gap balancing techniques using a contemporary knee system: a randomized controlled trial.

PURPOSE: The Attune® Knee System provides new instrumentation to achieve symmetric flexion/extension gaps in total knee arthroplasty (TKA). However, there is limited information on the optimal TKA technique using this system. The aim of this randomised controlled trial was to determine which surgical technique results in better postoperative clinical outcomes after TKA using the contemporary Attune® Knee System: the measured resection or gap balancing technique. METHODS: A prospective randomized controlled trial was conducted with 100 patients undergoing TKA using measured resection (n = 50) or gap balancing (n = 50) technique. The measured femoral sizer was used in the measured resection group, while the balanced femoral sizer was used in the gap balancing group. Functional outcomes and quality of life were assessed preoperatively and at 6 months and 2 years post-surgery, using the Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), Oxford Knee Score (OKS), the Physical Component Score (PCS) and Mental Component Score (MCS) of Short-Form 36 (SF-36). Using weight-bearing coronal radiographs, the hip-knee-ankle angle (HKA), coronal femoral component angle (CFA), coronal tibial component angle (CTA) and joint line height were also evaluated for each patient. RESULTS: There were no significant differences in the functional scores or the proportion of patients from each group who were satisfied or had their expectations fulfilled at 6 months or 2 years post-surgery. There was also no significant difference in the number of patients who attained minimum clinically important difference (MCID) postoperatively between the groups. Postoperatively, there was no significant difference in the number of HKA outliers between the groups (p = 0.202). The postoperative CFA (p = 0.265) and CTA (p = 0.479) were similar between the groups. There was also no significant difference in the absolute change (p = 0.447) or proportion of outliers (p = 0.611) for joint line height between the groups. CONCLUSION: Both measured resection and gap balancing techniques resulted in comparable functional and quality of life outcomes up to 2 years post-surgery. Both techniques appear to be equally effective in achieving excellent outcomes with the Attune® Knee System. LEVEL OF EVIDENCE: I.