Risks of major bleeding and venous thromboembolism in patients undergoing total hip or total knee arthroplasty using therapeutic dosages of DOACs.

About 1.5% of patients undergoing total hip (THA) or total knee arthroplasty (TKA) still develop postoperative venous thromboembolism (VTE), indicating that the current thromboprophylaxis strategy is not optimal. To evaluate the feasibility of therapeutic dosages of direct oral anticoagulants (DOACs) as thromboprophylaxis for high VTE risk patients, we determined the risks of major bleeding and VTE in patients who underwent THA/TKA and were treated with DOACs in therapeutic dosages for atrial fibrillation (AF). We conducted a registry-based cohort study from 2010 to 2018 in Denmark and included AF patients on therapeutic DOACs dose who underwent THA/TKA. AF patients were utilized as proxy since they have a life-long indication for therapeutic anticoagulant medication. The 49-days cumulative incidence (with death as competing risk) of major bleeding was assessed. The same was done for VTE at 49- and 90-days. 1,354 THA and TKA procedures were included. The 49-days cumulative incidence of major bleeding was 1.40% (95%Confidence Interval[CI] 0.88-2.14%). Most bleeding events occurred at the surgical site. The cumulative incidence of VTE at 49-days was 0.59% (95%CI 0.28-1.13%) and 0.74% (95%CI 0.38-1.32%) at 90-days. The incidence of major bleeding in THA/TKA patients on DOACs in therapeutic dosages was in line with previously reported incidences among THA/TKA patients on thromboprophylaxis dosages, while the incidence of VTE was relatively low. These data provide a solid basis for the design of randomized controlled trials to establish the safety and efficacy of therapeutic dosages of DOACs to prevent VTE in high-risk patients.

Functional knee phenotypes appear to be more suitable for the Chinese OA population compared with CPAK classification: A study based on 3D CT reconstruction models.

PURPOSE: The aim of this study was to investigate the distribution of coronal plane alignment of the knee (CPAK) classification and functional knee phenotypes in a Chinese osteoarthritis (OA) population and to compare different lower limb alignment targets according to the distribution characteristics to find suitable total knee arthroplasty (TKA) bone cut strategies for the Chinese OA patients. METHODS: The computed tomography (CT) images were retrospectively collected and the three-dimensional (3D) models were reconstructed from 434 Chinese OA patients, including 93 males and 341 females, with a mean age of 66.4 ± 9.3 years. Femoral mechanical angle (FMA), tibial mechanical angle (TMA) and mechanical hip-knee-ankle angle (mHKA) were measured on the 3D models. Arithmetic hip-knee-ankle angle (aHKA) was calculated using FMA plus TMA, and joint line obliquity was calculated as 180 + TMA-FMA. The CPAK according to MacDessi and the functional knee phenotypes according to Hirschmann were performed. In addition, the suitable TKA bone cut strategies were explored according to the phenotypes and based on the characteristics of different alignment targets, such as mechanical alignment, anatomic alignment (AA), kinematic alignment, restricted KA (rKA) and adjusted MA (aMA). Statistical differences were determined using the independent-samples t-test or the two independent-samples Wilcoxon test, with p < 0.05 considered statistically significant. RESULTS: The Chinese OA population showed a varus alignment tendency (mHKA = 172.1° ± 7.2°), to which the TMA was a major contributor (TMA = 84.7° ± 4.4° vs. FMA = 91.3° ± 3.2°). The mHKA was on average 3.9° more varus than the aHKA. A total of 140 functional knee phenotypes were found and 45.6% were concentrated in VARFMA3°-NEUFMA0° to VARTMA3°-NEUTMA0°. More than 70% of patients had different FMA and TMA phenotypes. There were 92.9% of CPAK distributed in types I to IV, with type I accounting for 53.9%. The FMA phenotypes were less changed if the aMA and rKA were chosen, and the TMA phenotypes were less changed if the AA and rKA were chosen. CONCLUSION: Compared with the CPAK, the functional knee phenotypes were more suitable for the Chinese OA population with a wide distribution and a varus tendency, and it seemed more appropriate to choose aMA and rKA as TKA alignment targets for resection. LEVEL OF EVIDENCE: Level Ⅲ.

Inferior Outcomes for Patients Transferred Between Surgical Stages for Knee Periprosthetic Joint Infection.

BACKGROUND: Periprosthetic joint infection (PJI) in total knee arthroplasty may result in 2-stage revision surgery. There are limited data describing outcomes when the first stage is completed at an outside hospital and the patient is referred to a tertiary center. We hypothesized that patients have greater success when both surgeries occur at a single center. METHODS: There were 25 knee PJI patients who presented with an antibiotic spacer and had a minimum 2-year follow-up who were retrospectively identified at a single tertiary referral center from 2014 to 2021. A cohort matched for age, sex, body mass index, Elixhauser comorbidity measure, spacer type, infectious organism, and year of surgery was established with patients who had both stages completed at the investigating institution. Modified Delphi success criteria of no subsequent surgery or reinfection with any species were compared. RESULTS: The transferred group demonstrated a treatment success of 40% compared to 84% in the continuous group (P < .01). The transferred group was more likely to have an additional procedure between stages (44 versus 8%, P < .01), with a higher number of surgeries after primary total knee arthroplasty (4.8 versus 3.0, P < .01), between stages (1.4 versus 0.2, P < .01), and after second stage (0.8 versus 0.2, P = .03). The transferred group had longer durations between stages (20.1 versus 7.0 weeks, P < .01). CONCLUSION: Patients who have PJIs transferred between stages demonstrated higher treatment failure. Surgeons should consider transfer early with a goal of continuous management by a single institution.

Are social determinants of health associated with an increased length of hospitalization after revision total hip and knee arthroplasty? A comparison study of social deprivation indices.

INTRODUCTION: Length of stay (LOS) has been extensively assessed as a marker for healthcare utilization, functional outcomes, and cost of care for patients undergoing arthroplasty. The notable patient-to-patient variation in LOS following revision hip and knee total joint arthroplasty (TJA) suggests a potential opportunity to reduce preventable discharge delays. Previous studies investigated the impact of social determinants of health (SDoH) on orthopaedic conditions and outcomes using deprivation indices with inconsistent findings. The aim of the study is to compare the association of three publicly available national indices of social deprivation with prolonged LOS in revision TJA patients. MATERIALS AND METHODS: 1,047 consecutive patients who underwent a revision TJA were included in this retrospective study. Patient demographics, comorbidities, and behavioral characteristics were extracted. Area deprivation index (ADI), social deprivation index (SDI), and social vulnerability index (SVI) were recorded for each patient, following which univariate and multivariate logistic regression analyses were performed to determine the relationship between deprivation measures and prolonged LOS (greater than five days postoperatively). RESULTS: 193 patients had a prolonged LOS following surgery. Categorical ADI was significantly associated with prolonged LOS following surgery (OR = 2.14; 95% CI = 1.30-3.54; p = 0.003). No association with LOS was found using SDI and SVI. When accounting for other covariates, only ASA scores (ORrange=3.43-3.45; p < 0.001) and age (ORrange=1.00-1.03; prange=0.025-0.049) were independently associated with prolonged LOS. CONCLUSION: The varying relationship observed between the length of stay and socioeconomic markers in this study indicates that the selection of a deprivation index could significantly impact the outcomes when investigating the association between socioeconomic deprivation and clinical outcomes. These results suggest that ADI is a potential metric of social determinants of health that is applicable both clinically and in future policies related to hospital stays including bundled payment plan following revision TJA.

Construction of a Risk Prediction Model for Intraoperative Hypothermia in Patients Undergoing Lower Extremity Joint Replacement.

PURPOSE: To investigate the influencing factors of intraoperative hypothermia (IOH) in patients undergoing total joint arthroplasty (TJA) of the lower extremities, establish a risk prediction model, and test the effect of application. DESIGN: A prospective, observational study was conducted. METHODS: Patients who underwent total knee arthroplasty and total hip arthroplasty from June 2020 to December 2021 were prospectively analyzed. According to the occurrence of IOH, patients were divided into the IOH group (temperature less than 36 °C) and non-IOH group (temperature ≥36 °C). We collected demographic, anesthesia, and surgical data for both groups to identify risk factors for IOH and develop a predictive model. The model's goodness of fit was assessed using the Hosmer-Lemeshow test, and its predictive efficacy was evaluated using the receiver operating characteristic curve. FINDINGS: A total of 258 patients were included in this study, with 79 patients in the IOH group and 179 patients in the non-IOH group. Logistic regression analysis showed that American Society of Anesthesiologists' grade, blood loss, and duration of surgery were independent risk factors for IOH in lower extremity TJA patients. Hosmer-Lemeshow test P = .803, area under receiver operating characteristic curve was 0.846, Youden index was 0.490, sensitivity was 65.4%, specificity was 83.6%. In the external validation cohort, the application accuracy of the model was 83.3%. CONCLUSIONS: The prediction model established in this study is suitable for the risk assessment of IOH in TJA patients with good prediction effect, which can provide a tool for clinical medical staff to identify high-risk populations preoperatively.

Preoperative Predictors of Instrumental Activities of Daily Living Disability in Older Adults 6 Months After Knee Arthroplasty.

OBJECTIVE: To investigate preoperative predictors of instrumental activities of daily living (IADL) disability in older adults 6 months after knee arthroplasty (KA). DESIGN: Prospective cohort study. SETTING: General hospital with an orthopedic surgery department. PARTICIPANTS: Two hundred twenty (N=220) patients 65 years or older with total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: IADL status was evaluated for 6 activities. Participants chose "able," "need help," or "unable" according to their capacity of executing these IADL. If they chose "need help" or "unable" for 1 or more items, they were defined as "disabled." Their usual gait speed (UGS), range of motion for the knee, isometric knee extension strength (IKES), pain status, depressive symptoms, pain catastrophizing, and self-efficacy were evaluated as predictors. Baseline and follow-up assessments were conducted 1 month before and 6 months after KA, respectively. Logistic regression analyses with IADL status as the dependent variable were performed at follow-up. All models were adjusted using age, sex, severity of the knee deformity, operation type (TKA or UKA), and preoperative IADL status as covariates. RESULTS: In total, 166 patients completed the follow-up assessment, and 83 (50.0%) reported IADL disability 6 months after KA. Preoperative UGS, IKES on the non-operated side, and self-efficacy were statistically significantly different between those with a disability at follow-up and those who did not and were therefore included in logistic regression models as independent variables. UGS (odds ratio, 3.22; 95% CI, 1.38-7.56; P=.007) was determined as a significant independent variable. CONCLUSIONS: The present study demonstrated the importance of evaluating preoperative gait speed to predict the presence of IADL disability in older adults 6 months after KA. Patients with poorer preoperative mobility should be provided careful postoperative care and treatment.

Mechanically aligned total knee arthroplasty with the extension-first technique does not equally restore neutral knee alignment in all preoperative knee phenotypes.

PURPOSE: The aim of this study was to determine the change in the long leg axis according to the preoperative knee phenotype using the mechanically aligned extension-first technique in total knee arthroplasty. The hypothesis of this study was that the knee phenotype would have an impact on the postoperative leg axis. METHODS: This was a retrospective comparative study comprising 224 whole-leg radiographs of 112 patients. The leg axes of the pre- and postoperative radiographs were measured and categorized into three preoperative limb phenotypes (based on the hip-knee-ankle angle [HKA]) according to Hirschmann et al. (varus-HKA < 178.5°, neutral-HKA 178.5°-181.5°, and valgus-HKA > 181.5°). Additionally, femoral phenotypes (based on the femoral mechanical angle [FMA], i.e., the mechanical medial distal femoral angle [mMDFA], as well as the tibial phenotypes [based on the tibial mechanical angle, i.e., the medial proximal tibial angle (MPTA)] was calculated. The change in the long leg axis was analyzed and compared with the preoperative limb phenotype. RESULTS: Significantly more patients with preoperative varus alignment shifted to neutral alignment (46.3%, n = 31) than did patients with preoperative valgus alignment (38.9%; n = 14). Moreover, 43.3% of patients (n = 29) with the varus phenotype remained in a varus alignment, compared with the 58.3% of patients with preoperative valgus phenotype (n = 21) remaining in valgus alignment. These findings were similar for both females (p < 0.001) and males (p = 0.015). CONCLUSION: Using an extension-first mechanically aligned surgical technique, varus phenotypes predominantly result in neutral leg axes or remain varus, neutral phenotypes remain neutral, and valgus phenotypes remain valgus or change to neutral phenotypes. This study showed that preoperative knee phenotypes in valgus knees influence this technique more strongly than estimated in previous investigations, which is in line with modern alignment philosophies for TKA. LEVEL OF EVIDENCE: Level IV, retrospective comparative study.

[Periprosthetic gout flare after total knee arthroplasty: A misdiagnostic case report].

Periprosthetic gout flare is a rare arthritic condition after total knee arthroplasty, but the symptoms of gout may have often been mistaken as acute periprosthetic infection given their similarity. Misdiagnosis as periprosthetic infection can lead to unnecessary surgery, long-term dependence on anti-biotics, and even malfunction of the involved knee joint. Here, we report a case study of a patient with immunodeficiency condition of long-term oral glucocorticoid and diabetes mellitus, who had undergone a knee replacement 8 weeks before. The initial symptoms of fever and joint pain together with the dysfunction of her right knee with elevated inflammatory markers, such as increased serum leukocytes, erythrocyte sedimentation rate, C-reactive protein, and synovial cell counts led to a diagnosis of acute periprosthetic infection. Arthrocentesis and bacterial culture were performed preoperatively. According to the current Musculoskeletal Infection Society (MSIS) criteria for diagnosis of periprosthetic infection, the case was classified as periprosthetic infection and a prosthesis retained debridement surgery was performed. However we got negative culture results in all the pre-operative and intro-operative samples. The symptoms as well as the laboratory inflammatory markers improved shortly after the debridement surgery until the 11th day when all the similar systemic and local symptoms recurred. With a remedial crystal analysis of synovial fluid from the patient, gouty flare was found to be the cause of acute arthritis finally. Accor-dingly, after anti-gout medications were administrated, the symptoms associated with acute arthritis gra- dually subsided, and there was no recurrence during a 24-month follow-up. This article described the cli-nical manifestation, diagnosis and differential diagnosis, treatment of a case of periprosthetic gout. Although relatively rare, gout should be considered as a differential diagnosis in suspected periprosthetic infection. Current criteria for periprosthetic infection can not exclude the diagnosis of periprosthetic gout flare, it is therefore imperative that the analysis of joint aspirate for crystals be conducted to determine the correct course of treatment, or unnecessary surgical procedure may be performed in periprosthetic gout case.

[Cumulative sum control chart analysis of soft tissue balance in total knee replacement assisted by electronic pressure sensor].

OBJECTIVE: To explore the training ability of pad to guide the balance of soft tissue by drawing cumulative sum (CUSUM) control chart total knee arthroplasty (TKA) sensor. METHODS: The data of 73 knees of TKA assisted by electronic gasket initially completed by a senior physician were analyzed retrospectively. There were 8 males (8 knees) and 52 females (65 knees), with an average age of (67.5±5.9) years (57-82 years). The balance of the internal and external space of knee joint was measured at 0°, 45°, 90°, and 120°, in order to observe the pressure distribution of the medial and la-teral compartments, and CUSUM learning curve was drawn. RESULTS: In 0° extension, the medial pressure was higher than the lateral (P < 0.01), when flexion began, the medial and lateral pressures decreased, and became stable and approximately equal during 45°-120°. In the learning curve, by knee 34, CUSUM 0° curve crossed the acceptable control line from above, which showed that it was easy to grasp the soft tissue balance at 0° position through sensor learning. CUSUM 45° curve was above the unacceptable control line in the end, which meant that it was difficult to grasp the technique at the mid-flexion angle. CUSUM 90° and 120° crossed the acceptable control line from above by knee 68 and 57 respectively, which showed that the technique of balance could be improved with the aid of more cases. CONCLUSION: The electronic pressure sensor can effectively guide the soft tissue balance in TKA. The learning process is simple and does not increase the risk of complications. It can be used as a tool for learning TKA soft tissue balance technology to guide joint surgeons to further master or improve the soft tissue balance technology.

The effect of BMI on the mid-term clinical outcomes of mobile-bearing unicompartmental knee arthroplasty.

OBJECTIVE: To evaluate the impact of body mass index (BMI) on the mid-term clinical outcomes and survival in patients receiving a mobile-bearing unicompartmental knee arthroplasty (UKA). METHODS: We retrospectively collected data from 355 patients who underwent UKA from June 2006 to June 2015, with a mean follow-up of 106.5 ± 22.5 months. Patients were assigned into four groups based on their BMI before surgery: normal weight group (BMI 18.5 ~ 22.9 kg/m2), overweight group (23 ~ 24.9 kg/m2), obesity group (25 ~ 29.9 kg/m2), and severe obesity group (≥ 30 kg/m2). The knee society score (KSS), knee society function score (KSFS), hospital for special surgery score (HSS), and range of motion (ROM) were assessed before the operation and at the last follow-up. The femorotibial angle (FTA) was assessed after the operation immediately and at the last follow-up. Kaplan-Meier survival analysis was performed among the four groups. RESULTS: The KSS, KSFS, and HSS in all groups were markedly improved compared with the preoperative values (p<0.001), but the ROM score was not significantly different (p>0.05). There were significant differences in KSS (p<0.001) and HSS (p = 0.004) across the four BMI groups, and these differences were due to the severe obesity group. All groups exhibited an inclination of knee varus deformity at the last follow-up (p < 0.05). Moreover, no marked difference in the implant survival rate was found among the different groups (p = 0.248), or in the survival curves (p = 0.593). CONCLUSIONS: BMI does not influence the implant survival rate. The postoperative functional and quality-of-life scores were significantly improved in all groups. Obese (BMI ≥30 kg/m2) individuals should not be excluded from UKA.

Thromboprophylaxis with unilateral pneumatic device led to less edema and blood loss compared to enoxaparin after knee arthroplasty: randomized trial.

BACKGROUND: Pharmacological and mechanical thromboprophylaxis are frequently used together after total knee arthroplasty (TKA). Most studies in this context compare anticoagulants versus a combination of these drugs with an intermittent pneumatic compression device (IPCD). However, there is uncertainty about the need for the combination of both and whether a unilateral IPCD would alone affect other important clinical outcomes: edema and blood loss. We compared the effects of enoxaparin versus unilateral portable IPCD after TKA on edema and blood loss. We hypothesised that unilateral IPCD would cause the same level of edema and the same blood loss as enoxaparin. METHODS: In this open, randomized trial (1:1), adults with no history of coagulation disorders, anticoagulant use, venous thromboembolism, liver or malignant diseases underwent TKA. For 10 days, participants received the IPCD, used 24 h/day on the operated leg from the end of surgery, or 40 mg of enoxaparin, starting 12 h after surgery. All underwent the same rehabilitation and were encouraged to walk on the same day of surgery. We measured edema (thigh, leg and ankle circumference) before and on the third postoperative day. Blood loss (volume accumulated in the suction drain and drop of hemoglobin and hematocrit in 48 h) was a secondary outcome. RESULTS: We randomized 150 patients and lost 3 to follow-up with enoxaparin and 2 with IPCD. There was no case of symptomatic venous thromboembolism. Four patients needed transfusions (three receiving enoxaparin), one had infection and one hemarthrosis (both in the enoxaparin group). Leg circumference increased by approximately 2 cm for enoxaparin group and 1.5 cm in IPCD (p <  0.001). The increase in ankle circumference was about 1.5 cm in the enoxaparin group (p <  0.001), and almost zero in IPCD (p = 0.447). Enoxaparin group lost 566.1 ml (standard deviation, SD, 174.5) of blood in the first 48 h, versus 420.8 ml (SD 142.5) in the IPCD. CONCLUSIONS: Exclusively mechanical prophylaxis after TKA with portable IPCD only on the operated leg reduces leg and ankle swelling and post-operative blood loss compared to exclusively pharmacological prophylaxis with enoxaparin. Portable devices that can prevent deep vein thrombosis and pulmonary embolism without increasing blood loss or other risks should be further investigated. TRIAL REGISTRATION: REBEC RBR-8k2vpx. Registration date: 06/04/2019.

Insufficient evidence to confirm benefits of custom partial knee arthroplasty: a systematic review.

PURPOSE: The purpose of this systematic review was to synthesise the available literature and critically appraise current evidence on the functional and radiographic outcomes as well as reoperation and revision rates of custom partial knee arthroplasty, i.e., unicompartmental knee arthroplasty (UKA), bicompartmental knee arthroplasty (BKA), and patellofemoral arthroplasty (PFA). MATERIAL AND METHODS: This systematic review was performed in accordance with the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and a protocol was registered with Prospero. On 25 May 2021, two authors independently searched and screened Level I-IV studies that reported on outcomes of custom partial knee arthroplasty using the databases of MEDLINE®, EMBASE®, and the Cochrane Library without restriction on date of publication. Findings from eligible articles were synthesised and tabulated, and quality assessments were done according to the guidelines of the Joanna Briggs Institute (JBI) Checklists. RESULTS: Fifteen articles were eligible for data extraction, of which two comparative and four case series were on custom UKA (follow-up, 0-9 months), one comparative and five case series on custom BKA (follow-up, 0.25-72 months), and three case series on custom PFA (follow-up, 2-119 months). Three studies on custom UKA reported mean Knee Society Score (KSS) Knee of 86-94 and mean KSS Function of 94-95, and two studies on custom BKA reported mean KSS Knee of 90-94 and KSS function of 81, whereas one study on custom PFA reported KSS Knee of 91 and KSS Function of 89. Custom implants tended to have less bone-implant mismatch compared to off the shelf (OTS) implants. Revision rates were 3-25% for custom UKA (at 0-109 months), 3-5% for custom BKA (at 12-72 months), and 0-14% for custom PFA (at 2-119 months). CONCLUSION: Due to the small number of comparative studies and lack of consistency in reported outcomes, it remains difficult to ascertain the benefits of custom partial knee arthroplasty. Anecdotal evidence suggests that, compared to OTS implants, custom implants result in less bone-implant mismatch and that 78-91% of patients are either satisfied or very satisfied after custom partial knee arthroplasty. LEVEL OF EVIDENCE: IV.

New Classification for Periprosthetic Distal Femoral Fractures Based on Locked-Plate Fixation Following Total Knee Arthroplasty: A Multicenter Study.

BACKGROUND: This study aimed to establish a new classification using locked-plate fixation for periprosthetic distal femoral fracture (PDFF) following total knee arthroplasty (TKA) and to determine when dual locked-plate fixation is necessary through defining this classification. METHODS: One-hundred fifteen consecutive PDFFs that underwent operative treatment were reviewed from 2011 to 2019 with minimum 1-year follow-up. Most PDFFs were fixed with single or dual locked-plate fixations using the minimally invasive plate osteosynthesis technique. Based on preoperative radiographs, PDFFs were classified according to the level of main fracture line relative to the anterior flange of femoral component: type I and II, main fracture line located proximal and distal to the anterior flange; and type III, component instability regardless of fracture line requiring revisional TKA. Furthermore, type II fractures were subclassified based on the direction of fracture beak as follows: type IIL, lateral-beak; type IIM, medial-beak. The incidence, treatment methods, and complications were analyzed according to the classification. RESULTS: Incidences of type I, IIL, IIM, and III were 64.4%, 8.7%, 24.3%, and 2.6%, respectively. Meanwhile, most PDFFs in type I and II were treated with lateral single locked-plate fixations, except for type IIM, which was treated with either single or dual locked-plate fixations. Overall complications were significantly higher in type II (28.9%) than in type I (10.8%, P = .019). In type IIM, bone union-related complications were significantly higher in single locked-plate fixation (50.0%) than in dual locked-plate fixation (5.6%; P = .013). CONCLUSION: The new classification provides practical and obvious strategies for the treatment of PDFF following TKA using locked-plate fixation. For type IIM fracture, dual plate fixation is necessary to prevent fixation failure or nonunion.

Volume and Outcomes of Joint Arthroplasty.

BACKGROUND: Joint arthroplasties are among the most commonly performed elective surgeries in the United States. Surgical outcomes are known to improve with volume but it is unclear whether this has led to consolidation among elective surgeries. We examined trends in volumes per surgeon and hospital to assess whether the known volume-outcome relationship has led to consolidation in elective joint arthroplasty and to determine if there exist volume thresholds above which outcomes do not change. METHODS: Among Medicare beneficiaries who underwent either total knee or total hip arthroplasty from 2009 through 2015, we described volume trends and used mixed-effect models to relate annual surgeon and hospital volumes with 30-day complications or mortality. We tested for optimal volume cut points at both the hospital and surgeon level. RESULTS: Adjusted annual complication rates were inversely associated with volume for both procedures at both the surgeon level and hospital level, but there was minimal consolidation between 2009 and 2015. Complications no longer declined after volumes of each case exceeded 260 per year. The vast majority of cases (around 93% of hip and 88% of knee arthroplasties) were performed by surgeons operating at suboptimal volumes. CONCLUSION: More than 2 decades after the volume-outcome relationship was established for joint arthroplasty, many cases continue to be performed by low-volume surgeons, with far more cases performed by surgeons operating at suboptimal volumes. Further improvement could be expected through consolidation at both the hospital and surgeon level, with a target of at least 260 cases per surgeon annually for each operation. Payers seem best-equipped to drive consolidation.

Clinical outcomes of fast-track total knee arthroplasty for patients aged >80 years.

INTRODUCTION: Because of the ageing population in Hong Kong, there is an increasing incidence of total knee arthroplasties (TKA) conducted in patients aged >80 years. METHODS: This retrospective case-control study enrolled all patients who were aged >80 years and underwent fast-track primary TKA between 2011 and 2015. Their outcomes were compared with the outcomes of a matched control group of younger patients who underwent fast-track TKA in the same period. RESULTS: In total, 220 patients were included in this study with a follow-up period of at least 2 years (mean=3.2 years; range, 2-5 years); 112 (51%) were octogenarians and 108 (49%) were non-octogenarians. Greater improvement in Knee Society Score was found in the octogenarian group at 1 year after surgery (46 ± 19 vs 39 ± 16, P=0.018). The incidence of complications was higher in the octogenarian group (15.2% vs 4.6%, P=0.009). There were no significant differences in the incidence of major complications, the rate of intensive care unit admission, or the 1-year mortality rate between the two groups. After adjustment for confounding factors, Charlson Comorbidity Index >5, history of major cerebrovascular accident, and history of peptic ulcer disease were predictive of complications after fast-track TKA (P=0.039, P=0.016, and P=0.007, respectively); octogenarian status was not predictive of complications. CONCLUSIONS: Octogenarians had greater improvement in Knee Society Score at 1 year after fast-track TKA, compared with non-octogenarians, but there were no significant differences in the incidences of mortality or major complications.

[Patient factors influencing preoperative expectations of patients undergoing total knee arthroplasty].

OBJECTIVE: To investigate the expectations of patients for total knee arthroplasty (TKA), and to analyze its influencing factors. METHODS: Experimental design: Single center, retrospective, multiple regression analysis. The data including the age, height, and weight of 108 patients undergoing unilateral TKA due to end-stage osteoarthritis were obtained. The patients' preoperative Hospital for Special Surgery (HSS) knee arthroplasty expectation score, the Western Ontario and McMaster Universities (WOMAC) score, Knee Society score (KSS), the MOS 36-item short-from health survey (SF-36) score, and visual analogue scale (VAS) were evaluated, and the 30-second chair-stand test (30-CST), 40-meter fast-paced walk test (40-FPWT), 12-level stair-climb test (12-SCT), 3-meter timed up-and-go test (TUG), 6-minute walk test (6-MWT), and recorded daily steps for 7 consecutive days were performed. The SPSS 22.0 software was used for statistical analysis. The observed values of various data were described. Pearson correlation analysis was used to evaluate the correlation between various parameters, and the multi-factor linear regression analysis was used to investigate the influencing factors of the patients preoperative expectation scores. RESULTS: The average expectation score of this group of patients was 58.98±5.44. In the Pearson correlation analysis, the patient's preoperative expectation had a weak correlation to the result of the patient's 12-SCT, TUG, 6-MWT, KSS function score, and SF-36 mental component score (correlation coefficient 0.1-0.3). The patient's preoperative expectation had a moderate correlation to the patient's daily average steps, 30-CST, 40-FPWT, KSS, WOMAC and its pain, stiffness, function scores, SF-36 physical functioning, role-physical, bodily pain, vitality, and physical component score (correlation coefficient 0.3-0.6). In the multivariate linear regression analysis, only the results of 30-CST and the role-physical, bodily pain and vitality in the SF-36 scale were related to the patient's expectation score (P < 0.05). CONCLUSION: The estimated expectation score of patients before TKA is not high. Patients with more severe preoperative pain, worse physical function, and lower overall health are more eager to improve after surgery. Thus surgeons must communicate fully with patients with unrealistic expectations before surgery in order to obtain more satisfactory results postoperatively.

Stationary Behavior and the Step-Defined Sedentary Lifestyle Index in Older Adults After Total Knee Arthroplasty.

OBJECTIVES: To measure stationary behavior in a cohort of older adults after total knee arthroplasty (TKA) and determine the clinical utility of the step-defined sedentary lifestyle index (SLI) as a measure of stationary behavior after TKA. DESIGN: Cross-sectional measurement study. SETTING: Participants were recruited from a community intake clinic for hip and knee surgeries. PARTICIPANTS: Sixty-five older adults 3 months after TKA (N=65). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Stationary behaviors, including stationary time, stationary bouts, breaks from stationary time, and the proportion of participants meeting the SLI, were measured in older adults 3 months post TKA using accelerometry. A 2-way analysis of variance test (α=0.05) was conducted to determine the effects of SLI (<5000 or ≥5000 daily steps) and possible interactions with sex on stationary behavior. RESULTS: Participants spent 80% (13.17±2.3h) of their waking time in stationary time and had an average of 6.06 bouts of stationary time >30 minutes per day. Forty (61.5%) of the participants fell below the SLI of 5000 steps/d. SLI had significant effects on both waking stationary time (P<.001) and number of breaks in stationary time (P<.001), with participants taking <5000 daily steps having longer stationary times and fewer breaks in stationary time. Sex had a significant effect on the number of breaks in stationary time (P=.04), with men (n=23, 35%) reporting more breaks than women (n=42, 65%) (mean difference 13.36; 95% confidence interval, -2.67 to 18.69). No interactions were found between SLI and sex. CONCLUSIONS: Both women and men had high levels of stationary behavior 3 months post TKA. The SLI discriminated waking stationary time and breaks in stationary time and may have clinical utility in measurement of stationary behavior.

Short-Term Effect of Peer Volunteers in Providing Inpatient Rehabilitative Exercises for Patients After Total Knee Arthroplasty.

OBJECTIVE: To investigate the short-term outcomes at discharge of patients who receive additional postoperative rehabilitative exercises by peer volunteers after total knee arthroplasty (TKA). DESIGN: Retrospective cohort study. SETTING: Tertiary teaching hospital. PARTICIPANTS: A total of 476 adult patients who had undergone a primary elective unilateral TKA (N=467). INTERVENTIONS: An intervention group received a standardized postoperative rehabilitative exercise protocol taught and supervised by peer volunteers in additional to standard physiotherapy (n=309) compared with a control group receiving standard physiotherapy alone (n=167). MAIN OUTCOME MEASURES: Discharge outcomes were the pain score using the Numeric Rating Scale pain score, passive knee flexion and extension range of motion (ROM), length of hospitalization, ability to perform an unassisted straight leg raise of the operated leg, ambulation distance, ability in independent walking, walking aids required, discharge destination, and adverse events. RESULTS: On multivariate analysis, patients in the intervention group had an increased discharge passive knee flexion ROM of 7.89 degrees (95% confidence interval, 5.47-10.33; P<.001). There were no significant differences for the other outcome measures between the intervention and control group. CONCLUSIONS: A rehabilitative exercise program by peer volunteers is feasible and safe after TKA in addition to standard physiotherapy and is associated with improved knee flexion ROM on discharge.

Adductor canal block with or without added magnesium sulfate following total knee arthroplasty: a multi-arm randomized controlled trial.

PURPOSE: Postoperative analgesia following total knee arthroplasty (TKA) often includes intrathecal opioids, periarticular injection (PAI) of local anesthetic, systemic multimodal analgesia, and/or peripheral nerve blockade. The adductor canal block (ACB) provides analgesia without muscle weakness and magnesium sulphate (MgSO4) may extend its duration. The purpose of this trial was to compare the duration and quality of early post-TKA analgesia in patients receiving postoperative ACB (± MgSO4) in addition to standard care. METHODS: Elective TKA patients were randomized to: 1) sham ACB, 2) ropivacaine ACB, or 3) ropivacaine ACB with added MgSO4. All received spinal anesthesia with intrathecal morphine, intraoperative PAI, and multimodal systemic analgesia. Patients and assessors remained blinded to allocation. Anesthesiologists knew whether patients had received sham or ACB but were blinded to MgSO4. The primary outcome was time to first analgesic (via patient-controlled analgesia [PCA] with iv morphine) following ACB. Secondary outcomes were morphine consumption, side effects, visual analogue scale pain scores, satisfaction until 24 hr postoperatively, and length of stay. RESULTS: Of 130 patients, 121 were included. Nine were excluded post randomization: four were protocol violations, three did not meet inclusion criteria, and two had severe pain requiring open label blockade. There were no differences in the median [interquartile range] time to first PCA request: sham, 310 min [165-550]; ropivacaine ACB, 298 min [120-776]; and ropivacaine ACB with MgSO4, 270 min [113-780] (P = 0.96). Similarly, we detected no differences in resting pain, opioid consumption, length of stay, or associated side effects until 24 hr postoperatively. CONCLUSION: We found no analgesic benefit of a postoperative ACB, with or without added MgSO4, in TKA patients undergoing spinal anesthesia and receiving intrathecal morphine, an intraoperative PAI, and multimodal systemic analgesia. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02581683); registered 21 October 2015.

RéSUMé: OBJECTIF: L'analgésie postopératoire suivant une arthroplastie totale du genou (ATG) inclut souvent des opioïdes intrathécaux, une injection périarticulaire (IPA) d'anesthésique local, une analgésie multimodale systémique, et/ou des blocs des nerfs périphériques. Le bloc du canal des adducteurs (BCA) permet une analgésie sans faiblesse musculaire et le sulfate de magnésium (MgSO4) pourrait prolonger sa durée. L'objectif de cette étude était de comparer la durée et la qualité de l'analgésie post-ATG précoce chez les patients recevant un BCA postopératoire (± MgSO4) en plus des soins standard. MéTHODE: Des patients devant subir une ATG non urgente ont été randomisés à recevoir : 1) un BCA placebo (groupe témoin), 2) un BCA avec ropivacaïne, ou 3) un BCA avec ropivacaïne et MgSO4. Tous ont reçu une rachianesthésie avec morphine intrathécale, une IPA peropératoire, et une analgésie multimodale systémique. L'allocation a été faite à l'insu des patients et des évaluateurs. Les anesthésiologistes savaient si les patients avaient reçu un placebo ou un BCA, mais n'étaient pas informés de l'ajout ou non de MgSO4. Le critère d'évaluation principal était le temps jusqu'à la première prise d'analgésique (via une analgésie contrôlée par le patient [ACP] avec de la morphine iv) après le BCA. Les critères secondaires comprenaient la consommation de morphine, les effets secondaires, les scores de douleur sur l'échelle visuelle analogue, la satisfaction jusqu'à 24 heures postopératoires, et la durée de séjour. RéSULTATS: Sur 130 patients, 121 ont été inclus. Neuf ont été exclus après la randomisation : quatre l'ont été en raison de violations du protocole, trois ne répondaient pas aux critères d'inclusion, et deux ont ressenti des douleurs graves nécessitant un bloc sans insu. Aucune différence n'a été observée dans le temps médian [écart interquartile] jusqu'à la première demande d'ACP : placebo, 310 min [165-550]; BCA ropivacaïne, 298 min [120-776]; et BCA ropivacaïne avec MgSO4, 270 min [113-780] (P = 0,96). De la même manière, nous n'avons détecté aucune différence dans la douleur au repos, la consommation d'opioïdes, la durée de séjour, ou les effets secondaires associés jusqu'à 24 heures postopératoires. CONCLUSION: Nous n'avons trouvé aucun avantage analgésique à un BCA postopératoire, avec ou sans ajout de MgSO4, chez les patients subissant une ATG sous rachianesthésie et recevant de la morphine intrathécale, une IPA peropératoire, et une analgésie multimodale systémique. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT02581683); enregistrée le 21 octobre 2015.

Comparing ERAS-outpatient versus standard-inpatient hip and knee replacements: a mixed methods study exploring the experience of patients who underwent both.

BACKGROUND: Optimizing patients' total hip and knee arthroplasty (THA/TKA) experience is as crucial for providing high quality care as improving safety and clinical effectiveness. Yet, little evidence is available on patient experience in standard-inpatient and enhanced recovery after surgery (ERAS)-outpatient programs. Therefore, this study aimed to gain a more in-depth understanding of the patient experience of ERAS-outpatient programs in comparison to standard-inpatient programs. METHODS: We conducted a convergent mixed methods study of 48 consecutive patients who experienced both standard-inpatient and ERAS-outpatient THA/TKA contralaterally. A reflective thematic analysis was conducted based on data collected via a questionnaire. Bivariate correlations between the patient experience and patients' characteristics, clinical outcomes and care components satisfaction were performed. Then, the quantitative and qualitative data were integrated together. RESULTS: The theme Support makes the difference for better and for worse was identified by patients as crucial to their experience in both joint replacement programs. On the other hand, patients identified 3 themes distinguishing their ERAS-outpatient from their standard-inpatient experience: 1) Minimizing inconvenience, 2) Home sweet home and 3) Returning to normal function and activities. Potential optimization expressed by patients were to receive more preoperative information, additional postoperative rehabilitation sessions, and ensuring better coherence of care between hospital and home care teams. Weak to moderate positive and statistically significant correlations were found between patients' THA/TKA experience and satisfaction with pain management, hospital stay, postoperative recovery, home care, and overall results (rs = + [0.36-0.66], p-value < 0.01). CONCLUSION: Whatever the perioperative program, the key to improving patients' THA/TKA experience lies in improving support throughout the care episode. However, compared to standard-inpatient care, the ERAS-outpatient program improves patients' experience by providing dedicated support in postoperative care, reducing postoperative inconvenience, optimizing pain management, returning home sooner, and recovering and regaining function sooner. Patients' THA/TKA experience could further be enhanced by optimizing the information provided to the patient, the rehabilitation program and the coherence between care teams.