Primary Unilateral Total Knee Arthroplasty Research Articles

Association of intraoperative dexmedetomidine use with postoperative hypotension in unilateral hip and knee arthroplasties: a historical cohort study.

Dexmedetomidine is frequently used as a sedative agent for orthopedic surgery patients undergoing total hip or knee arthroplasty. Although the benefits of dexmedetomidine are well described in the literature, there is also potential for harm, especially regarding the hemodynamic effects of dexmedetomidine in the postoperative setting. This historical cohort study included all primary unilateral total hip or knee arthroplasties conducted from April 2017 to February 2020 in a single, university-affiliated, tertiary care centre (Jewish General Hospital, Montreal, QC, Canada). We used multivariable logistic regression to analyze the predictors for postoperative hypotension, defined as a systolic blood pressure < 90 mm Hg or any systolic blood pressure while on a vasopressor infusion in the postanesthesia care unit. Models were validated using calibration and discrimination with bootstrapping technique. One thousand five hundred and eighty-eight patients were included in this study. Postoperative hypotension occurred in 413 (26%) patients. Statistically significant predictors for postoperative hypotension included female sex (adjusted odds ratio [aOR], 3.24; 95% confidence interval [CI], 2.29 to 4.58), a history of transient ischemic attack or cerebrovascular accident (aOR, 1.97; 95% CI, 1.04 to 3.72), and intraoperative dexmedetomidine use (aOR, 2.61; 95% CI, 1.99 to 3.42). Moreover, the risk of postoperative hypotension was approximately two times higher than baseline, with a total intraoperative dexmedetomidine dose above 50 μg (relative risk, 1.99; 95% CI, 1.63 to 2.44; P < 0.001). A higher preoperative systolic blood pressure (aOR, 0.98; 95% CI, 0.97 to 0.99) was a protective factor for postoperative hypotension. In this historical cohort study, dexmedetomidine was a strong risk factor for postoperative hypotension in total hip or knee arthroplasty patients. Dexmedetomidine, and particularly at high cumulative doses above 50 μg, should be administered judiciously in high-risk surgical patients to minimize the risk of postoperative hypotension.

Risk factors for contralateral total knee arthroplasty after unilateral total knee arthroplasty

BackgroundLittle attention has been focused on risk factors for undergoing bilateral total knee arthroplasty (TKA) after primary unilateral TKA among patients with knee osteoarthritis (OA). This study investigated the differences in characteristics between groups with and without additional TKA for the contralateral knee among patients with knee OA who underwent primary unilateral TKA. MethodsSeventy-six patients who underwent primary unilateral TKA were included in this study. We defined patients who underwent additional TKA for the contralateral knee within one year of the primary TKA as a bilateral TKA group, and patients who did not undergo bilateral TKA as a unilateral TKA group. Femorotibial angle (FTA), percentage of mechanical axis (%MA), Kellgren–Lawrence (KL) grade, range of motion, Japan Orthopaedic Association (JOA) score, 10 m-walking time, C-reactive protein, estimated glomerular filtration rate, and serum albumin levels were selected as independent variables including covariates of age, sex, and body mass index for predicting bilateral TKA. We compared differences in variables between the two groups using the t-test or Mann–Whitney U-test and general linear models. A multivariate stepwise logistic regression model was also used to determine which variables correlated with bailateral TKA. ResultsIn pairwise comparisons, the KL grade, FTA, %MA, JOA score, and knee flexion angle in the contralateral knee were significantly worse in the bilateral TKA group than in the unilateral TKA group after controlling for covariates (P < 0.01, respectively). A stepwise logistic regression revealed that significant contributors to undergoing the contralateral TKA were FTA (OR = 1.47, P < 0.001) and knee flexion angle (OR = 0.96, P = 0.022) of the contralateral knee. ConclusionsSevere varus deformity and limitations of flexion in the contralateral knee were found to be risk factors for undergoing additional TKA within one year of primary unilateral TKA among patients with knee OA.

Prehabilitation Improves Knee Functioning Before and Within the First Year After Total Knee Arthroplasty: A Systematic Review With Meta-analysis.

OBJECTIVE: To assess whether prehabilitation influenced knee functioning before and within the first year after total knee arthroplasty (TKA) surgery. DESIGN: Intervention systematic review with meta-analysis. LITERATURE SEARCH: The authors searched the MEDLINE/PubMED, EMBASE, CINAHL, Cochrane Library, Physiotherapy Evidence Database, Web of Science, and Scopus databases from their inception until March 2022. STUDY SELECTION CITERIA: The authors included peer-reviewed articles comparing preoperative, short-, mid- or long-term effects of exercise-based physical therapy before primary unilateral TKA with TKA without prehabilitation. DATA SYNTHESIS: We assessed bias using the Cochrane Risk-of-Bias tool (ROB 2.0) and therapeutic validity using the i-CONTENT tool. Standardized mean differences (Hedges' g) and 95% confidence intervals (CIs) were calculated for knee functioning. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. RESULTS: Sixteen trials (968 participants) were included; 14 qualified for meta-analysis. Low to very low certainty of evidence favored prehabilitation over no intervention for improving knee functioning before (g = 1.23; 95% CI: 0.49, 1.97) and up to 3 months after TKA (short-term: 1 day to 1 month, g = 0.90; 95% CI: 0.18, 1.61; mid-term: 6 weeks to 3 months, g = 0.45; 95% CI: 0.06, 0.84). There were no significant between-group differences at long-term follow-up (6-12 months, g = 0.07; 95% CI: -0.17, 0.30). CONCLUSION: There was low to very low certainty of evidence that prehabilitation promotes superior knee functioning before and up to 3 months after TKA, compared to TKA alone. The long-term postoperative effects were inconclusive. J Orthop Sports Phys Ther 2022;52(11):709-725 Epub: 20 September 2022. doi:10.2519/jospt.2022.11160.

Synergistic effects of robotic surgery and IPACK nerve block on reduction of opioid consumption in total knee arthroplasty

BackgroundThere are numerous strategies to combat postoperative analgesia and expedite recovery after total knee arthroplasty (TKA). The purpose of this study was to determine opioid consumption, length of stay, and functional outcomes after robotic versus standard TKA in the setting of various regional pain modalities. MethodsA consecutive series of patients treated with unilateral primary robotic or standard TKA from January 2018–February 2021 were retrospectively identified. Regional pain modalities included peri-articular injection (PAI), adductor canal block (ACB), and infiltration between popliteal artery and capsule of knee (IPACK). Patient demographics, operative/perioperative variables, and postoperative function were recorded. Daily opiate consumption was calculated as morphine milligram equivalents (MME). Multivariate regression was performed to control for age, sex, and race. ResultsAfter review, 283 patients (177 Females; 106 Males) were included. Robotic TKA patients received IPACK + ACB (36), while standard TKA patients received either ACB (45), IPACK + ACB (167), or PAI (35). Daily inpatient opioid consumption in the standard IPACK + ACB (p = 0.02) and robotic IPACK + ACB groups (p = 0.0001) was significantly lower compared to standard ACB. When combined with IPACK block, robotic procedures synergistically lowered opiate consumption (p = 0.004) compared to standard procedures and led to earlier discharge (p = 0.003). The robotic IPACK + ACB cohort also demonstrated improved early ambulation compared to standard ACB, (p = 0.05), whereas the same benefit was not seen for patients who received IPACK during standard TKA. ConclusionsThe utilization of IPACK block decreases inpatient postoperative opioid requirements following TKA. Robotic TKA and IPACK block appeared to have a synergistic effect on opioid consumption and postoperative recovery.

Anterior Knee Pain Following Primary Unilateral Total Knee Arthroplasty With Posterior-Stabilized Prosthesis and Patellar Resurfacing: Prevalence and Clinical Implications

BackgroundAnterior knee pain following total knee arthroplasty (TKA) is associated with patient dissatisfaction. Factors related to postoperative anterior knee pain and its impact on patient outcomes are poorly understood. The following are the aims of this study: (1) to report the prevalence of anterior knee pain before and after TKA using a posterior-stabilized prosthesis with routine patellar resurfacing; (2) to investigate the association of preoperative clinical factors with the presence of anterior knee pain after TKA; and (3) to explore the association of postoperative anterior knee pain with postoperative self-reported function and quality of life. MethodsThis retrospective study included 506 patients who had undergone elective primary unilateral TKA with a posterior-stabilized prosthesis and patellar resurfacing. Outcome measures prior to and 12 months after TKA included self-reported anterior knee pain, knee function, and quality of life. ResultsPrevalence of anterior knee pain was 72% prior to and 15% following TKA. Patients who had preoperative anterior knee pain had twice the risk of experiencing anterior knee pain after TKA than patients who did not have preoperative anterior knee pain (risk ratio: 2.37, 95% CI 1.73-2.96). Greater severity of preoperative anterior knee pain and worse self-reported function were associated with the presence of postoperative anterior knee pain (rho = 0.15, P < .01; rho = 0.13, P < .01, respectively). Preoperative age, gender, and quality of life were not associated with postoperative anterior knee pain. Greater severity of postoperative anterior knee pain was associated with worse knee function at 12 months postoperative (rho = 0.49, P < .01). ConclusionOne in 7 patients reported anterior knee pain 12 months following posterior-stabilized and patella-resurfaced TKA. The presence of preoperative anterior knee pain and worse self-reported function are associated with postoperative anterior knee pain.

Medium Activity Prevents Periprosthetic Bone Mass Loss in the Medial Metaphyseal Region of the Tibia after Posterior-Stabilized TKA: A 5-Year Follow-up Study of 110 Knees.

ObjectiveThe bone mass around the prosthesis plays an important role in the stability of the prosthesis. This study aimed to assess the effect of postoperative activity on bone mineral density (BMD) in the proximal tibia 5 years after total knee arthroplasty (TKA). To provide a scientific guidance for postoperative functional exercise.Methods110 patients underwent unilateral primary TKA were divided into three groups based on the University of California Los Angeles (UCLA) activity scale: low activity group (LA group, UCLA = 4, 5); medium activity group (MA group, UCLA = 6, 7); and high activity group (HA group, UCLA = 8, 9). The primary observation was a comparison of the BMD and BMD change percentage (ΔBMD (%)) in the periprosthetic tibia among the LA, MA and HA groups at 1 year, 3 years and 5 years. The secondary observations were radiographic evaluation (prosthetic stability, periprosthetic fractures, aseptic loosening and periprosthetic joint infection) and clinical evaluation (Knee Society Score (KSS), visual analogue score scores and range of motion (ROM)). A one‐way ANOVA was used to compare the clinical scores and BMD among the three groups.ResultsThe BMD of medial region decreased by 10.80%, 12.64%, 13.61% at 1, 3, and 5 years respectively; these were 5.72%, 6.26%, 7.83% in lateral region and 1.42%, 1.78%, 3.28% in diaphyseal region. For medial metaphyseal region, the BMD of the MA group was significantly greater than that of the LA and HA groups at 1 and 3 years (108.9 ± 5.2 vs. 106.1 ± 6.69 vs. 105.4 ± 5.2 and 108.5 ± 6.0 vs. 101.2 ± 6.76 vs. 103.0 ± 6.8, P < 0.01 and P < 0.001), and the BMD changes (ΔBMD (%)) in the MA group were significantly smaller than those in the LA and HA groups (8.75 ± 5.36 vs. 11.92 ± 5.49 vs. 12.70 ± 5.21 and 9.11 ± 5.11 vs. 16.04 ± 4.79 vs. 14.82 ± 4.26, P < 0.01 and P < 0.001).Regarding secondary observations, all of the prostheses were assessed as stable, without periprosthetic fractures, aseptic loosening and periprosthetic joint infection. Regarding KSS scores, there was no significant difference among the three groups. However, the VAS and ROM of the HA group were better than those of the MA and LA groups (1.65 ± 0.79 vs. 2.63 ± 0.77 vs. 3.00 ± 1.17, p < 0.001, and 111.90 ± 9.17 vs. 110.20 ± 6.78 vs. 102.90 ± 8.48, P < 0.001).ConclusionMedium activity prevented periprosthetic bone loss in the medial metaphyseal region of the tibia after posterior‐stabilized TKA, and moderate‐intensity exercise is recommended for patients after TKA to reduce periprosthetic bone loss.

Does Aseptic Revision Risk Differ for Primary Total Knee Arthroplasty Patients Who Have and Do not Have a Prior Primary or Revision Arthroplasty?

BackgroundWe sought to evaluate the risk of aseptic revision in total knee arthroplasty (TKA) patients who have and do not have a history of primary or revision arthroplasty of a different major joint. MethodsWe conducted a matched cohort study using data from Kaiser Permanente’s arthroplasty registries. Patients who underwent primary unilateral TKA (index knee) were identified (2009-2018). Two matches based on exposure history were performed: (1) 33,714 TKAs with a history of primary arthroplasty of a different joint (contralateral knee, either hip, and/or either shoulder) were matched to 67,121 TKAs without an arthroplasty history and (2) 597 TKAs with a history of aseptic revision in a different joint were matched to 1,190 TKAs with a history of a prior arthroplasty in a different joint, but without any revision. After the matches were performed, Cox regressions were used to evaluate aseptic revision risk of the index knee using the no history groups as the reference in regression models. ResultsNo difference in aseptic revision risk for the index knee was observed when comparing patients who had a prior primary arthroplasty in a different joint to those who did not have an arthroplasty history (hazard ratio = 0.95, 95% CI = 0.86-1.06). Those patients who did not have any prior aseptic revision history in a different joint had higher risk of aseptic revision in the index knee (hazard ratio = 2.06, 95% CI = 1.17-3.63). ConclusionPatients who had a prior revision history had over a 2-fold higher risk of aseptic revision in the index knee, warranting close surveillance of these patients. Level of EvidenceLevel III.

Influence of vitamin D levels on outcomes and nosocomial COVID-19 infection in patients undergoing total knee arthroplasty- a cohort study

PurposeThis study aimed to audit the effects of vitamin D3 on the early functional outcomes, the incidence of nosocomial COVID-19 infection and complications in patients undergoing elective Total Knee Arthroplasty (TKA). MethodsThis was a retrospective study involving patients undergoing primary unilateral TKA between January 2020 to May 2021 operated by a single surgeon using a single implant. Participants were divided into two cohorts, Deficient-vitamin D3 level <20 ng/ml and Sufficient-vitamin D3 level ≥20 ng/ml. Assessment for Knee Society Score and Oxford Knee Score (OKS) was done preoperatively and one year after TKA. Nosocomial COVID-19 infection rate, 30-day re-admissions and complications were noted during the study. Results235 patients were divided into 2 cohorts matched by age, gender and ASA grades. 74 patients belonged to the deficient group and 161 belonged to the sufficient group. The mean preoperative scores in the sufficient group were higher than the deficient group (OKS = 15.74 vs 12.95; KSS = 88.91vs 85.62). Similarly, the one-year postoperative scores in the sufficient group were significantly higher (OKS = 36.54 vs 35.16; KSS = 164.01 vs 161.22). A linear correlation was present between preoperative score (r = 0.273) & post-operative scores (r = 0.141) with serum vitamin D3 levels. Vitamin D3 deficient individuals had higher nosocomial COVID-19 infection rate (10.81% vs 4.96%,p = 0.16). The incidence of complications like DVT, embolism, stroke, infection and fracture were not statistically different in the two groups. ConclusionVitamin D positively influences the outcomes of TKA and protects against nosocomial COVID-19 infection in patients undergoing elective TKA.

Effect of knee joint weight change on knee function recovery and gait after total knee arthroplasty

BackgroundKnee osteoarthritis (KOA) is a common disease based on degenerative pathological changes. Total knee arthroplasty (TKA) is an effective treatment for end-stage of KOA. However, only volume adaptation can be achieved with current knee prostheses, and it is difficult to achieve weight adaptation. This study focused on the weight difference of knee joints and initially explored the impact of this change on knee joint functional recovery and gait changes in patients after surgery.MethodsFrom October 2015 to June 2019, patients who underwent primary unilateral TKA were enrolled in this prospective cohort study with the same brand of knee prostheses. General data were collected from patients who met the criteria. The resected bone and soft tissues were collected and weighed precisely during TKA, and multivariate regression analysis was used to determine the factors affecting the weight of the removed knee tissues. We compared the weight of excised tissues and the total weight of the knee prosthesis, and the weight difference was defined as the increased weight of the knee joint (IWKJ). All patients were evaluated by HSS score, gait analysis, and affected side knee X-ray at two weeks, three months, and the last follow-up after the operation. To further determine the influence of IWKJ on postoperative functional recovery, the relationship between IWKJ, HSS score, and gait analysis was analyzed by univariate regression.ResultsIn total, 210 patients were eventually included in observation. All patients underwent postoperative follow-up for no less than two years. Multiple regression analysis showed that the course of the disease, body weight, and kellgren-Larencen stage(K-L stage)of the affected knee joint were independent factors affecting the weight of the removed knee tissues and were positively correlated with it. Univariate analysis showed that IWKJ was negatively correlated with HSS score at two weeks and three months after the operation. In addition, the values of spatiotemporal parameters and knee rotation ROM were negatively correlated with IWKJ two weeks after surgery, while outside food load response was positively correlated with IWKJ. Cadence, knee rotation ROM, and Ankle rotation ROM were negatively correlated with IWKJ, while outside food was positively correlated with IWKJ three months after surgery. At the last follow-up, only the hip rotation ROM was positively correlated with IWKJ.ConclusionsAll Patients underwent TKA had varying degrees of increased knee weight. The increased weight was 298.98 ± 63.77 g. Patients' body weight, K-L staging, and disease duration are important factors that cause differences in resected knee tissue. Three months after the operation, the changes in knee joint weight had a negative correlation with the HSS score, which at the same time, it had varying degrees of linearity with gait parameters. However, the influence of weight diminished over time.

Establishment of a qualified integrated care system after total knee arthroplasty as a role of regional rheumatoid and degenerative arthritis centers

BackgroundThe geriatric population and advanced knee osteoarthritis are rapidly increasing in Korea, and the socioeconomic burden of total knee arthroplasty (TKA) is increasing. This study aimed to analyze the demographic, clinical and socioeconomic characteristics of patients who underwent TKA and to differentiate the factors affecting participation in inpatient-intensive rehabilitation programs after TKA in the Jeju regional rheumatoid and degenerative arthritis center established by the government.MethodsThis retrospective cohort study included 845 patients (735 females; 72.0 ± 5.8 years) diagnosed with primary osteoarthritis (OA) of the knee who underwent elective unilateral primary TKA between January 2013 and June 2016. Demographic, clinical, and socioeconomic characteristics, including age, body mass index, obesity, length of stay, OA severity, underlying disease, education level, occupation, and location of residence were reviewed. Patients were allocated to the TKA-only group (home discharge) and to the TKA + rehab group (participation in post-TKA rehabilitation). The variables were analyzed and compared before and after the establishment of the center and according to participation in intensive rehabilitation.ResultsPatients who underwent TKA were mostly female, in the 60 s, and had a high prevalence of comorbidities and obesity. After the rehabilitation center's establishment, the intensive post-TKA participation increased profoundly from 3% to 59.2%. Participants after the center establishment had lower mean BMI and a higher proportion of K-L grade 4 compared to those before the center establishment. The location of residence was the only factor differentiating the participation in the intensive rehabilitation.ConclusionThe regional rheumatoid and degenerative arthritis center was appropriate to satisfy the high unmet need for participating in the intensive rehabilitation after TKA and to execute the qualified integrated post-TKA care system. Policy support should ensure the early rehabilitation and a qualified integrated care system and prepare for the increased burden of revision. Future longitudinal studies should be conducted to assess the long-term effect of the integrated post-TKA rehabilitation program on functional outcomes and patient survivorship free from revision.

Pain management after total knee arthroplasty: PROcedure SPEcific Postoperative Pain ManagemenT recommendations.

The PROSPECT (PROcedure SPEcific Postoperative Pain ManagemenT) Working Group is a global collaboration of surgeons and anaesthesiologists formulating procedure-specific recommendations for pain management after common operations. Total knee arthroplasty (TKA) is associated with significant postoperative pain that is difficult to treat. Nevertheless, pain control is essential for rehabilitation and to enhance recovery. To evaluate the available literature and develop recommendations for optimal pain management after unilateral primary TKA. A narrative review based on published systematic reviews, using modified PROSPECT methodology. A literature search was performed in EMBASE, MEDLINE, PubMed and Cochrane Databases, between January 2014 and December 2020, for systematic reviews and meta-analyses evaluating analgesic interventions for pain management in patients undergoing TKA. Each randomised controlled trial (RCT) included in the selected systematic reviews was critically evaluated and included only if met the PROSPECT requirements. Included studies were evaluated for clinically relevant differences in pain scores, use of nonopioid analgesics, such as paracetamol and nonsteroidal anti-inflammatory drugs and current clinical relevance. A total of 151 systematic reviews were analysed, 106 RCTs met PROSPECT criteria. Paracetamol and nonsteroidal anti-inflammatory or cyclo-oxygenase-2-specific inhibitors are recommended. This should be combined with a single shot adductor canal block and peri-articular local infiltration analgesia together with a single intra-operative dose of intravenous dexamethasone. Intrathecal morphine (100 μg) may be considered in hospitalised patients only in rare situations when both adductor canal block and local infiltration analgesia are not possible. Opioids should be reserved as rescue analgesics in the postoperative period. Analgesic interventions that could not be recommended were also identified. The present review identified an optimal analgesic regimen for unilateral primary TKA. Future studies to evaluate enhanced recovery programs and specific challenging patient groups are needed.

Validation of a Predictive Tool for Discharge to Rehabilitation or a Skilled Nursing Facility After TJA.

Cost excess in bundled payment models for total joint arthroplasty (TJA) is driven by discharge to rehabilitation or a skilled nursing facility (SNF). A recently published preoperative risk prediction tool showed very good internal accuracy in stratifying patients on the basis of likelihood of discharge to an SNF or rehabilitation. The purpose of the present study was to test the accuracy of this predictive tool through external validation with use of a large cohort from an outside institution. A total of 20,294 primary unilateral total hip (48%) and knee (52%) arthroplasty cases at a tertiary health system were extracted from the institutional electronic medical record. Discharge location and the 9 preoperative variables required by the predictive model were collected. All cases were run through the model to generate risk scores for those patients, which were compared with the actual discharge locations to evaluate the cutoff originally proposed in the derivation paper. The proportion of correct classifications at this threshold was evaluated, as well as the sensitivity, specificity, positive and negative predictive values, number needed to screen, and area under the receiver operating characteristic curve (AUC), in order to determine the predictive accuracy of the model. A total of 3,147 (15.5%) of the patients who underwent primary, unilateral total hip or knee arthroplasty were discharged to rehabilitation or an SNF. Despite considerable differences between the present and original model derivation cohorts, predicted scores demonstrated very good accuracy (AUC, 0.734; 95% confidence interval, 0.725 to 0.744). The threshold simultaneously maximizing sensitivity and specificity was 0.1745 (sensitivity, 0.672; specificity, 0.679), essentially identical to the proposed cutoff of the original paper (0.178). The proportion of correct classifications was 0.679. Positive and negative predictive values (0.277 and 0.919, respectively) were substantially better than those of random selection based only on event prevalence (0.155 and 0.845), and the number needed to screen was 3.6 (random selection, 6.4). A previously published online predictive tool for discharge to rehabilitation or an SNF performed well under external validation, demonstrating a positive predictive value 79% higher and number needed to screen 56% lower than simple random selection. This tool consists of exclusively preoperative parameters that are easily collected. Based on a successful external validation, this tool merits consideration for clinical implementation because of its value for patient counseling, preoperative optimization, and discharge planning. Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Effect of body mass index on symptomatic venous thromboembolism and prosthesis revision risk after total knee arthroplasty: a long-term study from China

ObjectiveTo investigate the effect of body mass index (BMI) on the risk of symptomatic VTE and prosthesis revision after total knee arthroplasty (TKA).MethodsSeven thousand one hundred eighty-two patients with primary unilateral TKA treated in our hospital from 2011 to 2020 were divided into four groups according to BMI: BMI < 25 kg/m2, BMI 25 kg/m2–29.9 kg/m2, BMI 30 kg/m2–34.9 kg/m2 and BMI ≥ 35 kg/m2. Incidence, Odds ratio and Kaplan-Meier survival analysis were used to evaluate the effects of BMI on symptomatic VTE and prosthesis revision risk after TKA.ResultsThe incidence of VTE after TKA was 8.9‰(64/7182). There was no significant difference in the incidence of VTE among different BMI groups(P = 0.452). Deep vein thrombosis mainly occurred in the distal lower extremities, especially in intermuscular veins. Revision rate of prosthesis after TKA was 6.4‰(46/7182). There was no significant difference in revision rate among different BMI groups(P = 0.718). In the univariate analysis of TKA, compared with patients with normal BMI, the risk of postoperative VTE and prosthesis revision in patients with overweight, obesity class I and obesity class II did not increase. Higher prosthesis revision rate and lower prosthesis survival rate were observed in BMI ≥ 35 kg/m2 group, although the difference was not statistically significant.ConclusionsThrough such a retrospective large sample data of long-term follow-up, we believe that the higher BMI was not associated with the increased risk of symptomatic VTE and prosthesis revision after TKA. When TKA was used for appropriate indications, high BMI should not be considered as a contraindication.

Outcomes of Patients Undergoing Total Knee Arthroplasty with Spinal Anesthesia: A Comparison of Mepivacaine versus Bupivacaine

Introduction: Previous literature indicates that mepivacaine used for spinal anesthesia may lead to reduced recovery time and urinary retention compared to bupivacaine in patients undergoing total knee arthroplasty (TKA). We sought to compare outcomes between spinal anesthetics in our high-volume joint institution. Materials and Methods: A retrospective review of 553 unilateral primary TKA patients who received spinal anesthesia was conducted. Patients were divided by their receipt of mepivacaine or bupivacaine. Univariate comparisons before and after propensity score matching were used to compare outcomes for TKA patients receiving mepivacaine with those who did not. Results: Of the 553 patients, 102 received mepivacaine, and 451 received bupivacaine. After propensity score matching, patients who received bupivacaine experienced longer lengths of stay, received more oral morphine milligram equivalents (OMMEs), and were less likely to be discharged home. No differences in rates of nausea, urinary retention, or 30-day readmissions were observed between the groups. Discussion: In patients undergoing TKA with a spinal anesthesia, after adjusting for potentially confounding factors using propensity score matching, the use of mepivacaine was associated with shorter length of stay, less overall OMME requirements, and increased likelihood of home discharge, with no increase in complication rates. Based on these results, mepivacaine appears to be a viable alternative to bupivacaine for use in TKA rapid recovery protocols.

Effect of tourniquet on morphology and stiffness of quadriceps in patients receiving total knee arthroplasty: a randomized controlled trial

Objective: To evaluate tourniquet effect on the morphology and stiffness of quadriceps in patients receiving total knee arthroplasty (TKA). Methods: Total of 80 patients with primary knee osteoarthritis receiving unilateral primary TKA from August 2020 to June 2021 in Peking University Third Hospital were enrolled in this randomized controlled trial. The patients were randomly divided into tourniquet group and non-tourniquet group (40 cases in each group). The study measured and compared postoperative thickness and stiffness of quadriceps, as well as circumference of the affected thigh in two groups. Results: There were 11 males and 29 females in tourniquet group, 9 males and 31 females in non-tourniquet group, with mean age of (69.1±5.1) years and (67.4±5.3) years, respectively. There was no significant difference in demographic information such as gender, age and BMI (all P<0.05). Postoperative thickness of quadriceps, stiffness of quadriceps and circumference［x¯±s or M （Q1，Q3）］of the affected thigh in all patients were (2.76±0.69) cm, 25.20 (17.83, 32.90) m/s, 54.00 (51.13, 56.00) cm. These outcomes in tourniquet and non-tourniquet group［x¯±s or M （Q1，Q3）］were (2.78±0.76) cm and (2.73±0.61) cm, 24.00 (17.15, 33.13) m/s and 25.20 (18.68, 32.85) m/s, 54.00 (49.75, 55.00) cm and 54.50 (52.13, 57.53) cm, respectively; no significant deference was found in these indexes between the two groups (all P>0.05). Conclusion: Tourniquet has no significant effect on morphology and stiffness of quadriceps in patients undergoing TKA.

The role of routine laboratory tests after unilateral total knee arthroplasty

BackgroundRecent studies suggest that routine laboratory tests are not required within 1 day after partial knee arthroplasty. In this study, we evaluated the utility of routine postoperative laboratory tests after initial unilateral total knee arthroplasty (TKA) in an Asian population. In addition, we explored risk factors associated with abnormal test results.MethodsClinical data of patients who underwent original unilateral TKA between 2015 and 2020 were retrospectively analyzed. Patient characteristics and laboratory test results were recorded. Multivariate binary logistic regression analysis was performed to identify risk factors associated with 3 abnormal laboratory results.ResultsA total of 713 patients, who underwent relevant laboratory tests within 3 days of TKA surgery, were enrolled. Among them, 8.1%, 9.9%, and 3.4% patients with anemia, hypoalbuminemia, and abnormal serum potassium levels required clinical intervention after surgery. Binary logistic regression analysis revealed that preoperative hemoglobin levels, estimated blood loss, and age were independent risk factors of postoperative blood transfusion in TKA patients. On the other hand, preoperative albumin levels, intraoperative blood loss, and operation time were risk factors associated with postoperative albumin supplementation. In addition, lower body mass index (BMI) and preoperative hypokalemia were potential risk factors of postoperative potassium supplementation.ConclusionConsidering that more than 90% of abnormal postoperative laboratory tests do not require clinical intervention, we believe that routine laboratory tests after surgery have little significance in patients with primary unilateral TKA. However, postoperative laboratory testing is necessary for patients with established risk factors.

Revisiting Short-term Outcomes of Conventional and Computer-Assisted Total Knee Arthroplasty: A Population-based Study.

Background:Population-based studies showing the advantage of computer-assisted total knee arthroplasty (CATKA) over conventional total knee arthroplasty (TKA) are outdated. More recent institution-based studies with relatively small sample sizes may hinder wider adoption. This cohort-based study aimed to compare postoperative CATKA and TKA in-hospital complications and 90-day all-cause readmissions using 2017-2018 data.Methods:Patients who underwent a primary unilateral CATKA or TKA were identified in the New York Statewide Planning and Research Cooperative System database. In-hospital complications were defined based on the 2020 Centers for Medicare & Medicaid Services total hip arthroplasty and TKA complications measure. Ninety-day readmissions were identified using unique patient identifiers. Logistic regression with a generalized estimating equation was used to assess associations of computer assistance with in-hospital complications and 90-day all-cause readmissions.Results:A total of 80,468 TKAs were identified during the study period, of which 7,395 (9.2%) were CATKAs. Significantly fewer complications occurred among patients who had CATKAs compared with conventional TKAs (0.4% of total CATKAs vs 2.6% of total conventional TKAs, P < 0.001); patients who had CATKAs had fewer 90-day all-cause readmissions compared with those who underwent TKAs (363 vs 4,169 revisits, P < 0.01). Computer assistance was associated with significantly lower odds of in-hospital complications (odds ratio, 0.15, 95% confidence interval, 0.09 to 0.24; P < 0.05) but not 90-day all-cause readmissions.Conclusion:Patients undergoing CATKAs had markedly lower odds of in-hospital complications, compared with patients having TKAs, which has implications for both patient outcomes and hospital reimbursement. These more recent cohort-based findings encourage wider CATKA adoption.

The Prevalence and Predictors of Patient Dissatisfaction 5-years Following Primary Total Knee Arthroplasty.

Previous studies have evaluated patient dissatisfaction after total knee arthroplasty (TKA) at 1 year, but there is no data about the prevalence of dissatisfaction among TKA patients after prolonged follow-up. The purpose of this study is to determine patient dissatisfaction 5-years after TKA and to identify patient factors predictive of dissatisfaction. Demographic and clinical data on 4402 patients undergoing primary unilateral TKA between 2012 and 2015 were collected prospectively through the Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR) comparative effectiveness consortium including diverse community and academic practices distributed across 23 states in the United States. Data collected at 1 year preoperatively and 5 years postoperatively included patient satisfaction (using a 5-point Likert satisfaction scale) and patient-reported outcome measures (PROMs) including the Knee injury and Osteoarthritis Outcome Score (KOOS) and Short-Form health survey (36-item). A univariate analysis of the difference between the satisfied and dissatisfied patients' groups was performed. A multivariate logistic regression model with 95% confidence interval (CI) was used to identify independent predictors of dissatisfaction at 5 years. The regression model was performed after adjusting the following variables: age, gender, body mass index (BMI), Charlson Comorbidity Index (CCI), marital status, smoking, education, and insurance type. The Receiver Operating Characteristic (ROC) analysis was performed with the measurement of area under curve (AUC). Hosmer-Lemeshow goodness of fit test was performed to evaluate the validity of the model. A total of 12.7% patients (559/4402) reported dissatisfaction 5-years after TKA. Increased BMI, higher CCI, higher Oswestry disability index, and increased number of other painful lower extremities (LE) joints were significantly associated with dissatisfaction. Higher rates of dissatisfaction were present in young patients, patients with less education, and non-White patients. Patient dissatisfaction was significantly associated with poor preoperative and 5-year postoperative PROMs scores and less score improvement from baseline to 5 years (P < .001). The multivariate regression analysis showed that an increased number of other painful LE joints (OR= 1.81; 95% CI (1.14-2.88) (P= .01), increased Oswestry back disability index (OR= 1.40; 95% CI (1.07-1.82) (P= .01), non-White patients (OR= 1.74; 95% CI (1.26-2.40) (P= .001), and minimal preoperative functional disability with KOOS function in daily living (ADL) score ≥70 (OR= 0.64; 95% CI (0.43-0.95) (P= .02) were independent predictive factors for dissatisfaction at 5 years. A total of 12.7% patients reported dissatisfaction 5-years after TKA. Clinical profiles of the satisfied and dissatisfied patients were captured 5-years after TKA with differences in the preoperative demographic and clinical characteristic variables identified. Risk factors for long-term patient dissatisfaction after TKA have been identified and should be considered during shared decision making while planning for TKA. Surgeons should use these identified risk factors to set realistic expectations for patients at an increased risk for dissatisfaction aiming to optimize their outcomes and increase their long-term satisfaction after TKA.

Robotic-assisted surgery and kinematic alignment in total knee arthroplasty (RASKAL study): a protocol of a national registry-nested, multicentre, 2×2 factorial randomised trial assessing clinical, intraoperative, functional, radiographic and survivorship outcomes

IntroductionRobot-assisted surgery (RAS) and kinematic alignment (KA) are being increasingly adopted to improve patient outcomes in total knee arthroplasty (TKA). There is uncertainty around the individual or combined effect of...

Effect of joint immobilization using extension splint immediately after total knee arthroplasty on post-operative knee function and pain: a randomized clinical trial.

Investigate the effect of semirigid extension bracing after total knee arthroplasty (TKA) on articular pain and function. The present randomized clinical trial included 72 patients undergoing unilateral primary TKA. Patients in the case group received eight days of post-operative semirigid extension-locked knee bracing, whereas controls did not. The outcomes assessed preoperatively and on the first, ninth, 30th day, and oneyear post-operatively included the knee society score (KSS), functional KSS (FKSS), VAS pain score, amount of postoperative opiate painkiller usage (tablet oxycodone 5mg), and knee ROM. The case group had a significantly lower flexion ROM on postoperative day nine compared to the control group (95.3° vs. 100.8°, p=0.03), while it became significantly higher 1 month (114.1° vs. 104.7°, p=0.03) and one year post-operative (128.0° vs. 120.5°, p=0.002). Also, FKSS was significantly higher in the case group than in the controls in the onemonth post-operative assessment (37.0 vs. 32.6, p=0.009) but not in the oneyear post-operative assessment. The case group patients had a significantly lower pain than the controls on days one (5.8 vs. 7.2, p=0.02) and nine post-operative (4.1 vs. 5.2, p=0.048), but not at later assessments. The amount of onemonth post-operative opium (oxycodone) consumption was significantly lower in the brace group (12.4 vs. 14.1 tablets, p=0.03). The KSS were not significantly different between the groups after the surgery. Extension-locked splinting immediately after TKA is a noninvasive, non-pharmacological, and inexpensive intervention with possible promising effects on knee ROM, short-term functional improvement, and acute post-operative pain management.