Changes in the anteroposterior position of the femur relative to the tibia impact patient satisfaction in total knee arthroplasty.

BACKGROUND: In this study, we aimed to investigate the preoperative and postoperative anteroposterior position (AP) of the femur relative to the tibia in total knee arthroplasty (TKA) and assess the influence of change in the AP position on clinical outcomes. METHODS: We evaluated 49 knees that underwent bi-cruciate-substituted TKA using a navigation system. The preoperative and postoperative AP position of the femur relative to the tibia at maximum extension, 15°, 30°, 45°, 60°, 90°, 105°, and 120° and maximum flexion angles were calculated. The 2011 Knee Society Score was evaluated preoperatively and 1 year postoperatively. The Wilcoxon signed rank and Spearman's rank correlation tests were performed, with statistical significance set at P < 0.05. RESULTS: The postoperative AP position was significantly correlated with the preoperative AP position at each measured angle. The postoperative AP positions were statistically more anterior than those preoperatively. Furthermore, the changes in the AP position after TKA negatively correlated with the symptom (P = 0.027 at 30°, P = 0.0018 at 45°, P = 0.0003 at 60°, P = 0.01 at 90°, and P = 0.028 at 105°) and patient satisfaction (P = 0.018 at 60° and P = 0.009 at 90°) scores at 1 year postoperatively. CONCLUSION: The postoperative AP position of the femur relative to the tibia was strongly influenced by the preoperative those in TKA. Postoperative anterior deviation of the femur relative to the tibia from mid-flexion to deep flexion could worsen clinical outcomes.

Commercially available activity monitors such as the fitbit charge and apple watch show poor validity in patients with gait aids after total knee arthroplasty.

PURPOSE: The aim of this study is to determine the validity of consumer grade step counter devices during the early recovery period after knee replacement surgery. METHODS: Twenty-three participants wore a Fitbit Charge or Apple Watch Series 4 smart watch and performed a walking test along a 50-metre hallway. There were 9 males and 14 females included in the study with an average age of 68.5 years and BMI of 32. Each patient wore both the Fitbit Charge and Apple Watch while completing the walking test and an observer counted the ground truth value using a thumb-push tally counter. This test was repeated pre-operatively with no gait aid, immediately post operatively with a walker, at 6 weeks follow up with a cane and at 6 months with no gait aid. Bland-Altman plots were performed for all walking tests to compare the agreement between measurement techniques. RESULTS: Mean overall agreement of step count for pre-operative and at 6 months for subjects walking without gait aids was excellent for both the Apple Watch vs. actual and Fitbit vs. actual with bias values ranging from - 0.87 to 1.36 with limits of agreement (LOA) ranging between - 10.82 and 15.91. While using a walker both devices showed extremely little agreement with the actual step count with bias values between 22.5 and 24.37 with LOA between 11.7 and 33.3. At 6 weeks post-op while using a cane, both the Apple Watch and Fitbit devices had a range of bias values between - 2.8 and 5.73 with LOA between - 13.51 and 24.97. CONCLUSIONS: These devices show poor validity in the early post operative setting, especially with the use of gait aids, and therefore results should be interpreted with caution.

Trends and epidemiology in robotic-assisted total knee arthroplasty: Reduced complications and shorter hospital stays.

INTRODUCTION: This study provides an in-depth analysis of the immediate postoperative outcomes and implications or robotic-assisted total knee arthroplasty (RA-TKA) compared with conventional TKA (C-TKA), particularly with regard to mortality, complications, hospital stay and costs, drawing from a comprehensive nationwide data set. METHODS: The Nationwide Inpatient Sample (NIS) database, the largest all-payer inpatient healthcare database in the United States, was used to identify all patients who underwent RA-TKA or C-TKA from 2016 to 2019. A total of 527,376 cases, representing 2,638,679 patients who underwent elective TKA were identified, of which 88,415 had RA-TKA. To mitigate potential variations and selection bias in baseline characteristics between the two groups, a propensity score-matched analysis was employed to further balance and refine our data set, resulting in 176,830 patients evenly distributed between the groups. Analysis was performed according to demographics, immediate post-operative complications, and economic data, including payor class, length of stay and total charges. RESULTS: There was a marked shift towards RA-TKA, from an initial 0.70% in 2016 to a notable 7.30% by 2019. Patients who underwent RA-TKA were slightly younger (66.2 ± SD years), compared to the C-TKA group (66.7 ± SD years). Hospital stay was 1.89 days and 2.29 days for RA-TKA and C-TKA, respectively. Charges metrics revealed slightly higher charges for RA-TKA. Less postoperative complications were found in the RA-TKA group, such as blood loss, anaemia, acute kidney injury, venous thromboembolism, pulmonary embolism, pneumonia and surgical wound complication. Even following the propensity score matching, these findings remained consistent and statistically significant. CONCLUSIONS: RA-TKA use in the United States has grown substantially in the last few years and has been associated with significantly reduced immediate post-operative complications and length of hospital stay compared to C-TKA, offering safer surgical management for TKA patients. Further studies on the short- and long-term outcomes of RA-TKA would improve the understanding of the full potential of this technology. LEVELS OF EVIDENCE: Level III.

Equivalent Clinical Outcomes Between Anatomical Alignment Versus Mechanical Alignment of Simultaneous Bilateral Total Knee Arthroplasty Using a Posterior-Stabilized Prosthesis During an Average Follow-Up of Five Years: A Prospective Randomized Clinical Trial.

BACKGROUND: This study aimed to investigate the differences in clinical outcomes between anatomical alignment and mechanical alignment in each knee, respectively, in patients who underwent bilateral total knee arthroplasty. METHODS: Bilateral simultaneous total knee arthroplasty using a posterior-stabilized prosthesis was performed between June 2016 and May 2018, with one knee undergoing anatomical alignment and the contralateral knee undergoing mechanical alignment, which was randomized. There were 80 knees in 40 patients (mean age 75 years, range 60 to 87, with 4 men and 36 women) followed up for at least two years (mean follow-up 4.9 years, range 2 to 7y). On the anatomical side, the distal femoral cut was set 2° more valgus to the mechanical axis, and the tibial cut was set to 2 or 3° varus using a specific guide. Implant position and lower extremity alignment were measured using postoperative radiographs and computed tomography images. The range of motion before and after surgery, Knee Society score, patient satisfaction, postoperative 2011 Knee Society questionnaire, and Knee Injury and Osteoarthritis Outcome Scores were evaluated. RESULTS: A significant difference was observed in joint line orientation (0.6 versus 2.9°, P < 0.001), but not in the postoperative hip-knee-ankle angle between two groups. There was one knee in the mechanical alignment group that required revision surgery at five years due to implant loosening. Before surgery, the anatomical alignment group had a significantly lower knee extension angle (-7.2 versus -6.0º, P = 0.035) and Knee Society score (46.1 versus 49.1, P = 0.046). No significant difference was observed between the groups except for the 2011 Knee Society questionnaire satisfaction scores (26.7 versus 25.7, P = 0.035). More participants preferred the anatomical alignment side postoperatively. CONCLUSION: Anatomical and mechanical alignments had similar clinical outcomes in patients undergoing bilateral total knee arthroplasty at a mean of 4.9 year follow-up.

The Impact of Diagnosed Chronic Sleep Disorders on Outcomes Following Total Knee Arthroplasty.

BACKGROUND: Up to 20% of patients undergoing total knee arthroplasty (TKA) remain dissatisfied with their outcome, leading to the identification of risk factors for poor outcomes. The purpose of this study was to analyze the effect of chronic sleep disorders on patient-reported outcomes after primary TKA. METHODS: A retrospective review of patients undergoing primary TKA was conducted using a prospectively collected database of patients from a single institution between 2018 and 2022. The cohort was split based on the presence of documented chronic sleep disorders, identified preoperatively from the electronic medical record using Current Procedural Terminology (CPT) codes. The sample was further restricted to include all patients who have sleep disorders (SD), as well as a 3:1 propensity-matched (on age, sex, Body Mass Index (BMI), and American Society of Anesthesiologists (ASA) class) cohort of patients who had no documented sleep disorders (NSD) prior to surgery. The final sample included 172 patients (SD: 43; NSD: 129). Repeated measures linear mixed model analysis was used to analyze the progression of Knee Injury and Osteoarthritis Outcome Score (KOOS) scores through time between groups. RESULTS: Those who had SD had a lower preoperative mean total KOOS score (40.2) compared to the NSD group (44.1), however, this was not significantly different (P = 0.108). At one year postoperatively, those who had a SD had a significantly higher mean total KOOS score (87.2) when compared to the NSD group (80.4), P = 0.005. When comparing total KOOS scores by group, over each time period, the SD group showed a better progression when compared to the NSD group, P = 0.001. CONCLUSION: Compared to patients who did not have documented chronic sleep disorders, patients who had a prior history of chronic sleep disorders reported significantly greater improvements in most KOOS domains in the 12-month period following TKA.

Determining factors on length of stay in primary total knee arthroplasty patients using enhanced recovery protocol after surgery (ERAS) pathway. / Factores determinantes de la duración de la estancia hospitalaria en pacientes operados de artroplastia primaria total de rodilla usando un protocolo de recuperación mejorada (ERAS).

INTRODUCTION: There is an increase in degenerative arthropathies because of the increase in the longevity of world's population, making primary knee arthroplasties a procedure to recover quality of life without pain. There are factors associated with the length of hospital stay after this procedure. OBJECTIVE: To determine the risk factors influencing the hospital stay during the postoperative period of patients undergoing primary total knee arthroplasty with an enhanced recovery after surgery protocol (ERAS). METHODS: A retrospective study is carried out on patients undergoing primary total knee arthroplasty at a University Hospital in the period 2017-2020 using the ERAS protocol, during which 957 surgeries were performed. RESULTS: Average age of 71.7 ± 8.2 years, 62.4% were women and the 77.3% were classified as ASA II. The significantly associated factors to an increased length of stay are: age (P = .001), ASA scale (P = .04), day of surgery (P < .001), blood transfusion (P < .001), postoperative haemoglobin level at 48-72 h (P < .001), the time of first postoperative mobilization to ambulate and climb stairs (P < .001), the need for analgesic rescues (P = .003), and the presence of postoperative nausea and vomiting (P = .008). CONCLUSIONS: There are statistically significant and clinically relevant factors associated with hospital stay. Determining these factors constitutes an advantage in hospital management, in the development of strategies to improve and optimize the quality of care and available health resources.

One-day surgery is safe and effective in unicompartmental knee arthroplasty: A prospective comparative study at 1 year of follow-up.

PURPOSE: To compare the outcomes and complications of two perioperative protocols for the management of patients who underwent medial unicompartmental knee arthroplasty (UKA): 24 h (1-day surgery [OS]) versus 72 h (enhanced recovery after surgery [ERAS]) of the length of hospital stay (LOS). In our hypothesis, the reduction of the LOS from 3 to 1 day did not influence the outcomes and complications. METHODS: A total of 42 patients (21 in each group) with isolated anteromedial knee osteoarthritis and meeting specific criteria were prospectively included in the study. Clinical outcomes included Knee Society Score (KSS) and Forgotten joint score while pain evaluation was performed using a Visual Analogue Scale (VAS). Functional outcomes were assessed measuring the knee range of motion (ROM) while radiographic outcomes were evaluated measuring the amelioration of the varus deformity through the hip-knee-ankle angle (HKA). RESULTS: Clinical and functional outcomes did not significantly differ between the two groups. Complications occurred in 9.5% of OS and 4.7% of ERAS group patients. Significant improvements in knee ROM, VAS pain, KSS and HKA angle were observed postsurgery, with no significant differences between groups except in KSS expectations and function trends. CONCLUSION: The OS protocol is safe and effective and LOS, in a well-defined fast-track protocol, did not significantly impact clinical and functional outcomes. OS may lead to reduced hospitalisation costs and potential reductions in complications associated with prolonged stays, benefiting both patients and healthcare facilities. However, further research with larger sample sizes and longer follow-up periods is needed to confirm these findings. Early mobilisation and rehabilitation protocols are key components of successful patient recovery following UKA procedures. LEVEL OF EVIDENCE: Level II.

Are short term outcomes superior following total knee arthroplasty when infra-patellar fat pad is resected? A systematic review and meta-analysis.

BACKGROUND: Data suggests the infra-patellar fat pad (IPFP) is resected in the majority of total knee arthroplasty cases. Current literature suggests there may be scope for increasing preservations rates. A systematic review and meta-analysis of available literature was performed to assess if resection of IPFP resulted in superior patient outcomes. METHODS: Scopus, PubMed, Cochrane, Embase and CINAHL were systematically searched in February 2024 for articles of relevance and meta-analysis conducted. A standardized mean difference and confidence interval of 95% was calculated. An odds ratio was calculated for all included datasets. Heterogeneity was assessed for using the I2 statistic. RESULTS: Thirteen studies were included within this review. IPFP resection shortened the patella tendon at 6 months post-operatively (OR, 0.07; 95% CI, 0.02-0.12, P = 0.006). Results favoured preservation at 12 months post-operatively (OR, 0.02; 95% CI, -0.02 to 0.06, P = 0.32). Oxford Knee Society (OKS) results statistically favoured preservation at 6 months (OR, 1.57; 95% CI, 0.74-2.39, P = 0.0002). Findings at 12 months favoured resection (OR, -0.49; 95% CI, -5.39, 4.41, P = 0.84). Resection increased anterior knee pain at 6-12 months post-operatively (OR, 1.45; 95% CI, 1.12-1.89, P = 0.005). Combined subgroup analysis of flexion favoured resection (OR, -2.15; 95% CI, -6.52 to 2.22, P = 0.34). CONCLUSION: OKS and patella tendon length results favoured preservation at 6 months however did not reach minimal clinically important difference. Combined subgroup analysis of flexion did not yield a statistically significant result. Rates of anterior knee pain at 6-12 months favoured preservation.

Optimizing Total Knee Arthroplasty Rehabilitation with Telehealth Physical Activity Behavior Change Intervention: A Randomized Clinical Trial.

OBJECTIVE: Conventional total knee arthroplasty (TKA) rehabilitation has little impact on sedentary lifestyles that have negative long-term health consequences. The purpose of this trial was to determine the effect of telehealth-based physical activity behavior change intervention on physical activity and functional outcomes following TKA. METHODS: This study was a 2-arm, parallel randomized controlled superiority trial at a regional Veterans Affairs medical center. The participants were 92 US military Veterans (mean age = 65.7 [SD =7.8] y) undergoing unilateral TKA. The Physical Activity Behavior Change (PABC) intervention included telehealth-based self-management training (ten 30-minute sessions) delivered over 12 weeks. The control intervention included telehealth-based health education sessions that matched PABC frequency and duration. Both groups participated in standardized conventional outpatient rehabilitation. Physical activity, measured as average daily step count, was the primary outcome. Secondary outcomes were Life-Space Assessment questionnaire, 30-Second Chair-Stand test, Timed Up-and-Go Test, Six-Minute Walk test, Western Ontario and McMaster Universities Osteoarthritis Index, and Veterans RAND 12-Item Health Survey. The Self Efficacy for Exercise scale and daily time spent in different postures (sitting/lying, standing, stepping) were exploratory variables. Outcomes were measured at baseline (before surgery), mid-intervention (8 weeks after surgery), after the intervention (14 weeks after surgery; primary endpoint), and follow-up (38 weeks after surgery). RESULTS: The PABC group had an estimated 931 (95% CI = 42-1819) more daily steps than the control group from baseline to 14 weeks, though a between-group effect was not sustained at 38 weeks. There were no group differences in secondary outcomes. Participants included only military veterans using Veteran's Health Administration services. The intervention targeted self-management and did not include peer support. CONCLUSIONS: The PABC intervention improved physical activity for Veterans recovering from unilateral TKA at 14 weeks after surgery, though the effect was not sustained at 38 weeks. Physical function improved with rehabilitation but was not different between groups, indicating that physical function was not a primary driver of physical activity behavior. IMPACT: Conventional TKA rehabilitation has a negligible effect on free-living physical activity, which is relevant to long-term health outcomes. This trial identified telehealth physical activity self-management as effective in addressing activity behaviors, separate from conventional rehabilitation strategies.

Safety evaluation of outpatient vs inpatient unicompartmental knee arthroplasty: a systematic review and meta-analysis.

PURPOSE: This systematic review and meta-analysis aimed to evaluate the safety of outpatient and inpatient Unicompartmental Knee Arthroplasty (UKA) based on the incidence of adverse events. METHOD: A systematic search of the literature was performed in October 2022 on PubMed, Web of Science, Cochrane library, and Embase. The Meta package for R was used to perform the meta-analysis. RESULT: Five studies with a total of 26,301 patients were included. 5813 patients (22.1%) were treated with outpatient UKA, and 20,488 patients (77.9%) were treated with inpatient UKA. There were no statistically significant differences in the incidence of total complications (RR = 1.36, 95% CI = 0.64-2.89, Z = 0.79, P = 0.43), readmission (RR = 1.02, 95% CI = 0.40-2.60, Z = 0.05, P = 0.96), and venous thrombosis (RR = 1.43, 95% CI = 0.96-2.11, Z = 1.78, P = 0.08). Incidence rates were lower in outpatient UKA regarding urinary tract infection (RR = 1.48, 95% CI = 1.07-2.04, Z = 2.40, P = 0.02), pulmonary embolus (RR = 7.48, 95% CI = 1.80-31.17, Z = 2.76, P < 0.01), and transfusion (RR = 2.77, 95% CI = 1.63-4.71, Z = 3.78, P < 0.01). CONCLUSION: In summary, outpatient UKA shows lower incidences of hospital-acquired complications such urinary tract infection, pulmonary embolus, and transfusion. It's worth noting that the incidences of total complications, readmission, and venous thrombosis in outpatient UKA were not higher than the incidences of inpatient UKA, suggestting that outpatient UKA can be considered a safe alternative to inpatient UKA.

High Demand for Psychological Support in Patients Who Have Periprosthetic Hip and Knee Joint Infections: An Analysis of 13,976 Patients.

BACKGROUND: There is only sparse knowledge on the psychological burden of patients who have periprosthetic joint infections (PJI). The aim of our study was to assess the need for psychological support following total joint arthroplasty of the hip and knee. A special focus was set on patients who had aseptic and septic complications. METHODS: A total of 13,976 patients who underwent total hip (THA, n = 6,926) or total knee arthroplasty (TKA, n = 7,050) between January 1st, 2012 and December 31st, 2019 at a single institution were retrospectively evaluated for the postoperative need for a psychological consultation. Data was collected on age, sex, type of surgery, and indications for revision procedures. The need for a psychological consultation was assessed during the daily postoperative visits, which were further coordinated by two institutional psychologists. RESULTS: The average age was 68 years (range, 12 to 100), and there were 63.5% women. The overall rate of psychological consultations was 1.7%. Patients who had a septic indication for revision surgery had an 18.7-fold higher rate of postoperative psychological consultations compared to patients following primary surgery and a 5.4-fold higher rate compared to patients who had an aseptic indication. In detail, this rate was 1.0% in the primary subgroup, compared to 7.7% following revision arthroplasty (P < 0.001). In the revision subgroup, the rate was 17.9% for septic and 3.3% for aseptic revision arthroplasty cases (P < 0.001). Postoperative psychological consultations were twice as frequent in women (2.1%) compared to men (1.0%), P < 0.001. CONCLUSIONS: The present study raises awareness of the markedly high psychological burden in revision arthroplasty cases, in the view of the high estimated number of unknown cases. There is a significant correlation between PJI and the postoperative need for a psychological consultation, with women being at an even higher risk. Health care providers should aim at offering psychological support for patients who have a septic complication, with affected patients being at risk for psychological stress.

Periprosthetic Joint Infections of the Knee-Comparison of Different Treatment Algorithms.

Background: Periprosthetic joint infection (PJI) following total knee arthroplasty is a serious complication lacking evidence-based diagnostic and treatment protocols, particularly in ruling out persisting infection before reimplantation. Methods: This retrospective analysis assessed the mid-term outcomes of 66 patients undergoing septic two-stage knee revision surgeries from 2007 to 2013, diagnosed as per the Musculoskeletal Infection Society criteria. After implant removal and antibiotic treatment, reimplantation decisions were based on either joint aspiration, blood counts, and clinical examination (group A) or an open biopsy (group B). Both groups underwent meticulous debridement and spacer exchange during the interim period. Results: Late re-infection occurred in 12.1% of all patients. In group A, 13.8% experienced late re-infection, with 14.3% in subgroup A1 and 13.3% in subgroup A2. In group B, 10% had a late re-infection. No significant difference in re-infection or complication rates was found between the groups. Conclusions: The study did not demonstrate the superiority of group B's approach of open biopsy over group A's joint aspiration, clinical examination, and blood counts in preventing re-infection or reducing complications.

Time to Total Knee Arthroplasty (TKA) Post Intra-Articular Injection.

Background: Disease-modifying treatments are not currently developed to target the underlying causes of knee osteoarthritis (KOA). Corticosteroids (CS), hyaluronic acid (HA), and platelet-rich plasma (PRP) intra-articular (IA) injections are commonly used for patients that do not respond to non-pharmacological treatments, oral nonsteroidal anti-inflammatory, or pain medications to address solely KOA symptoms. Utilizing TKA as an endpoint in the KOA disease progression provides a basis to determine efficacy of this treatment pathway. The primary objective is to evaluate a large national database to determine the time between first injection and total knee arthroplasty in patients solely administered intra-articular IA, CS, and HA. Methods: A retrospective query was performed on a national, all-payer claims database (PearlDiver, Colorado Springs, CO, USA), a composite of over 160 million Health Insurance Portability and Accountability Act compliant orthopedic records across all states and territories of the United States spanning 2016 to 2022. The database was queried to produce three distinct cohorts for analysis (PRP, HA, and CS). A 4:1 case match was conducted to compare cohorts receiving a subsequent TKA. Kaplan-Meier survival analysis analyzed the TKA-free survival of patients within each group at 6 months and 1 to 4 years. The log-rank test was performed for comparisons between survival cohorts. Results: The PRP cohort had a total population of 3240 patients, of which 71 (2.2%) received a subsequent TKA. The corticosteroid cohort had a total population of 1,382,572, of which 81,271 (5.9%) received a subsequent TKA. The HA cohort had a total population of 164,000, of which 13,044 (8.0%) received a subsequent TKA. Due to the low population within the PRP group, this group was excluded from comparison. The mean time to TKA from first injection in the HA group was 377.8 days, while in the corticosteroid group it was 370.0 days. The proportions of TKA-free survival for CS and HA when compared at 4 years post-injection was similar between groups (p = 0.05). Discussion and Conclusion: Patients that received only IA-corticosteroids or IA-hyaluronic acid had a similar length of time between the first injection and the total knee arthroplasty associated with the injected joint. This evidence provides information for clinicians and patients alike when contemplating these non-surgical injection modalities for KOA. The similarity observed between these treatments supports the need for future research to determine whether there is any potential for reduction in healthcare costs for KOA treatment prior to TKA.

Comparing Complication Rates, Costs, and Length of Stay between Unicompartmental and Total Knee Arthroplasty: Insights from a Big Data Analysis Using the National Inpatient Sample Dataset.

Background: Unicompartmental knee arthroplasty (UKA) is increasingly used for knee osteoarthritis due to faster recovery, better range of motion, and lower costs compared to total knee arthroplasty (TKA). While TKA may offer longer-lasting results with lower revision rates, this study compares the relative benefits and limitations of UKA and TKA using the National Inpatient Sample (NIS) database. Methods: This retrospective analysis examined outcomes of elective UKA and TKA procedures from 2016 to 2019, identifying 2,606,925 patients via ICD-10 codes. Propensity score matching based on demographics, hospital characteristics, and comorbidities resulted in a balanced cohort of 136,890 patients. The present study compared in-hospital mortality, length of stay, postoperative complications, and hospitalization costs. Results: The results showed that UKA procedures increased significantly over the study period. Patients undergoing UKA were generally younger with fewer comorbidities. After matching, both groups had low in-hospital mortality (0.015%). UKA patients had shorter hospital stays (1.53 vs. 2.47 days) and lower costs (USD 55,976 vs. USD 61,513) compared to TKA patients. UKA patients had slightly higher rates of intraoperative fracture and pulmonary edema, while TKA patients had higher risks of blood transfusion, anemia, coronary artery disease, pulmonary embolism, pneumonia, and acute kidney injury. Conclusions: UKA appears to be a less-invasive, cost-effective option for younger patients with localized knee osteoarthritis.

Optimizing Tourniquet Pressure in Primary Total Knee Arthroplasty: Limb Occlusion Pressure vs Systolic Blood Pressure Method: A Randomised Controlled Study.

Background: This study aims to systematically compare the efficacy of two distinct approaches that is limb occlusion pressure (LOP) and systolic blood pressure (SBP) in determining the optimal tourniquet pressure for primary total knee arthroplasty. The overarching goal is to identify the method that yields superior outcomes in minimizing post-operative thigh pain while simultaneously reducing complications in our patient population. Methods: 311 patients scheduled for primary total knee replacement (TKR) were randomized in two groups. Group A (LOP) had 154 patients and group B had 157 patients. In group A, LOP was determined for all patients. After adding the safety margin, the tourniquet pressure was determined which was kept during the procedure. By adding 150 mm Hg to SBP in group B, the tourniquet inflation pressure was ascertained. Postoperatively, thigh pain was evaluated from day 1 to day 3 and at 6 weeks. Results: The average tourniquet pressure in group A patients having thigh circumference between 40 and 50 cm was 223.8 mm + - 19.8 mm Hg and in group B it was 262.1 + - 15.9 mm Hg (P < .01). Patients having thigh circumference between 51 and 60 cm had average tourniquet pressure of 240.07 + - 20.1 mm Hg in group A and 264.5 + - 17.4 mm Hg in group B (P < .01). The average tourniquet pressure for patients with thigh circumference more than 60 cm was 296 + /15.3 mm Hg in group A and 267.3 + /19.2 mm Hg in group B (P < 0.01). Conclusion: Tourniquet pressure determination based on the limb occlusion pressure (LOP) method provide less postoperative thigh pain and better range of motion. Graphical Abstract: Optimizing Tourniquet Pressure in Primary Total Knee Replacement: Limb Occlusion Pressure vs Systolic blood pressure method to minimize thigh pain.

Does Patellar Denervation with Electrocautery Benefits for Total Knee Arthroplasty without Patellar Resurfacing: A Meta-analysis of Randomized Controlled Trails.

To investigate the effects of patellar denervation (PD) and non-patellar denervation (NPD) after primary total knee arthroplasty (TKA) without patellar resurfacing, this study conducted systematic electronic searches in November 2023 using PubMed, Embase, Web of Science, Cochrane, and Scopus, adhering to Cochrane Collaboration recommendations. Only randomized controlled trials (RCTs) were included. Additionally, a manual search was performed to identify potentially eligible studies from the reference lists of review articles. Two researchers independently conducted literature reviews, data extraction, and risk of bias assessments. The outcome analysis encompassed the incidence of anterior knee pain (AKP), visual analogue scale (VAS), range of motion (ROM), American Knee Society Score (KSS), Oxford Knee Score (OKS), patellar score (PS), complications, and reoperations. Meta-analysis was executed using RevMan 5.3 software. To enhance the credibility of the study, TSA v0.9 software was utilized to perform power analysis on the overall efficacy of primary and secondary outcomes. Twelve studies involving 1745 patients (1587 knees) were included, with 852 undergoing PD and 893 undergoing NPD. Results indicated a superior reduction in AKP incidence in the PD group compared to the NPD group. Statistically significant differences were observed between PD and NPD in KSS, OKS, and PS. However, the upper limit of the 95% confidence interval for each outcome fell below the minimal clinically important difference (MCID). No significant differences were found in VAS and ROM between PD and NPD. Additionally, PD was not associated with an increased incidence of complications or reoperations. Within 12 months and beyond, PD was proven to be a beneficial intervention in reducing AKP following TKA without patellar resurfacing, achieved without an increase in complications or reoperations. Regarding KSS, OKS, and PS, the minimal advantage achievable through PD may not be clinically significant.

Robotic-assisted total knee arthroplasty reduces postoperative complications and length of stay without increased cost compared to navigation-guided techniques: A national analysis.

INTRODUCTION: This study compares postoperative outcomes of robotic-assisted total knee arthroplasty (RA-TKA) versus navigation-guided total knee arthroplasty (NG-TKA). Using Nationwide Inpatient Sample (NIS) data, it provides an analysis of postoperative complications, mortality, hospital costs and duration of stay. METHODS: The study analysed 217,715 patients (81,830 RA-TKA; 135,885 NG-TKA) using NIS data from 2016 to 2019. Elective TKA patients were identified through the International Classification of Diseases, 10th Revision codes. Statistical analyses, including logistic regression modelling, were performed using Statistical Package for the Social Sciences and MATLAB. RESULTS: RA-TKA patients were younger (66.1 vs. 67.1 years, p < 0.0001) and had similar mortality rates (0.024% vs. 0.018%, p = 0.342) but shorter length of stay (LOS) (1.89 vs. 2.1 days, p < 0.0001). Mean total charges were comparable between RA-TKA ($66,180) and NG-TKA ($66,251, p = 0.669). RA-TKA demonstrated lower incidences of blood-related complications (11.67% vs. 14.19%, p < 0.0001), pulmonary oedema (0.0306% vs. 0.066%, p < 0.0001), deep vein thrombosis (0.196% vs. 0.254%, p = 0.006) and acute kidney injury (AKI) (1.356% vs. 1.483%, p = 0.016). CONCLUSION: RA-TKA reduces postoperative complications and LOS without increasing costs, highlighting the relevance of this technology in patient care. LEVEL OF EVIDENCE: Level III.

Role and Results of Constrained Insert in Computer-Assisted Primary Total Knee Arthroplasty: A Propensity-Matched Study.

Purpose: Mild ligament imbalance is often encountered in the mediolateral plane during complex primary total knee arthroplasty. A constrained (CP) polyethylene insert compatible with the primary femur is useful to manage these cases without the need to fall back on revision implants. The aim of the study was to define the correct indications of the use of a CP insert based on objective data from computer assisted surgery and to compare the early results of a CP insert with a standard posterior stabilized (PS) insert through one-to-one propensity score matching. Methods: This is a retrospective case study from a prospectively collected database. One-to-one matching without replacement was used with a caliper width of 0.2 to match the scores between CP (N = 64) and PS groups (N = 1624), resulting in equal covariate matching of PS (N = 64) and CP (N = 64) cohorts. Patients were assessed radiographically and functionally at a minimum follow-up of 3 years. Result: Average coronal and sagittal plane deformities were similar in both the group CP (varus 13.1 ± 5.2 valgus 13 ± 7.9) and the group PS (varus 13.4 ± 4.6 valgus 10.9 ± 8.6). The average residual medial lateral gap difference was significantly higher in group CP (3.8 ± 1.8) in comparison to group PS (1.3 ± 1) (P < .05). A CP insert was chosen where mild ligament imbalance of 3-5 mm persisted after medial soft tissue releases in a varus knee and in cases with residual medial collateral ligament laxity in valgus knees. Conclusions: Constrained insert used with the primary femoral component is a valuable option to handle mild ligamentous instability in complex primary total knee arthroplasty after mechanical alignment is achieved with computer navigation. Level of Evidence: III.

Simultaneous Concurrent Bilateral Total Knee Replacement in a Patient With Bilateral Lipoma Arborescens With End-Stage Osteoarthritis.

A 78-year-old Thai male presented with chronic bilateral knee pain and swelling. X-ray imaging revealed osteoarthritis in both knees, with a suspicious soft tissue shadow. Magnetic resonance imaging suggested lipoma arborescens (LA). The patient underwent LA excision with a complete synovectomy, followed by simultaneous bilateral total knee arthroplasty (SBTKA). Pathological examination confirmed LA. At the 2-year follow-up, the patient reported no complications, adverse outcomes, or recurrence. The intervention improved joint function and pain relief, allowing for early ambulation and full weight-bearing post-surgery. This case highlights the success of complete synovectomy with SBTKA, addressing bilateral knee pathology concurrently. The combined approach reduced operative time and significantly improved joint function and pain relief, emphasizing the benefits of timely surgical intervention and suggest potential advantages of SBTKA for optimal patient outcomes.