A genetic correlation scan identifies blood proteins associated with bone mineral density.

BACKGROUND: Osteoporosis is a common metabolic bone disease that is characterized by low bone mass. However, limited efforts have been made to explore the functional relevance of the blood proteome to bone mineral density across different life stages. METHODS: Using genome-wide association study summary data of the blood proteome and two independent studies of bone mineral density, we conducted a genetic correlation scan of bone mineral density and the blood proteome. Linkage disequilibrium score regression analysis was conducted to assess genetic correlations between each of the 3283 plasma proteins and bone mineral density. RESULTS: Linkage disequilibrium score regression identified 18 plasma proteins showing genetic correlation signals with bone mineral density in the TB-BMD cohort, such as MYOM2 (coefficient = 0.3755, P value = 0.0328) among subjects aged 0 ~ 15, POSTN (coefficient = - 0.5694, P value = 0.0192) among subjects aged 30 ~ 45 and PARK7 (coefficient = - 0.3613, P value = 0.0052) among subjects aged over 60. CONCLUSIONS: Our results identified multiple plasma proteins associated with bone mineral density and provided novel clues for revealing the functional relevance of plasma proteins to bone mineral density.

Radiofrequency Ablation in Cooled Monopolar or Conventional Bipolar Modality Yields More Beneficial Short-Term Clinical Outcomes Versus Other Treatments for Knee Osteoarthritis: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials.

PURPOSE: To evaluate various radiofrequency ablation (RFA) treatments for knee osteoarthritis (OA) and determine the best modality, target, number of electrodes, and image guidance for improving knee pain and function. METHODS: Electronic databases were searched for randomized controlled trials (RCTs) comparing the efficacy of RFA treatments for knee OA from inception up to September 30, 2021. The primary outcome was the visual analog scale (VAS), and the secondary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Bayesian network meta-analysis was performed to synthesize the mean difference (MD) and rank the comparative effectiveness of treatments. RESULTS: A total of 21 eligible RCTs (from 2011 to 2021, involving 1,818 patients) with 8 RFA treatments, 6 intra-articular injections, NSAIDS, exercise, and placebo were assessed. Conventional bipolar genicular nerve RFA (GNRFA) had the greatest net benefit on the VAS at 6 months (MD, -5.5; 95% confidence interval [CI], -4.3 to -6.7; SUCRA, .98). And cooled monopolar GNRFA had the greatest net benefit on the WOMAC at 6 months (MD, -33; 95% CI, -37 to -29; SUCRA, .99). In conventional and pulsed modalities, bipolar RFA was associated with a significant decrease in VAS and WOMAC than monopolar RFA. Combining pulsed intra-articular RFA and platelet-rich plasma injection had no additional positive effects on VAS or WOMAC at 3 months. CONCLUSIONS: RFA is effective in improving both knee pain and function in patients with OA, at least in the short term (6 months). Patients respond better to the cooled modality than the conventional and pulsed modalities. Bipolar is more effective than monopolar for improving pain and function in conventional and pulsed modalities. Fluoroscopy and ultrasound guidance showed no differences in improving pain and function. The effectiveness of RFA in cooled modality using bipolar or in combination with various intra-articular injections remains to be compared. LEVEL OF EVIDENCE: II, systematic review and meta-analysis of Level I and II studies.

Radiologic restoration inaccuracy increases postoperative dislocation in primary total hip arthroplasty: a retrospective study with propensity score matching.

BACKGROUND: Dislocation is a complicated process and associated with multivariate etiology and risk factors. The purpose of this study was to verify if radiologic restoration inaccuracy increases postoperative dislocation in primary total hip arthroplasty (THA) individually or synergistically. METHODS: From 2017 to 2020, we identified 76 (1.9%) patients who suffered postoperative dislocations from 3926 THAs in our institution. After excluded patients with previously proven patient-related and implant-related risk factors, the remaining patients were used to match a 1:1 control patients who were without dislocation. The cup position (inclination and anteversion angles), hip offset (HO), leg length discrepancy (LLD), and abductor lever arm (ALA) were analyzed by univariate analyses and multivariate logistic regressions. RESULTS: Measurements on radiographs showed excellent interobserver agreement (intraclass correlation coefficient (ICC) 0.922-0.952) and intraobserver agreements (ICC 0.933-0.967). HO restoration inaccuracy (without ± 5 mm) was associated with higher dislocation risk (OR 4.241 95% CI 1.440-12.492, P = 0.009). The restoration inaccuracy of the cup position, LLD, or ALA could not increase the dislocation risk individually. When combining the radiologic restoration inaccuracy factors, the HO + LLD restoration inaccuracy and HO + ALA restoration inaccuracy increased the odds of postoperative dislocation (OR 12.056, 95% CI 1.409-103.127, P = 0.023; OR 4.770, 95% CI 1.336-17.028, P = 0.016, respectively). Combining the four risk factors of cup safe zone, HO, LLD, and ALA, patients with 3 or 4 radiologic restoration inaccuracy factors showed a higher risk of dislocation (OR 13.500, 95% CI 1.340-135.983, P = 0.027). CONCLUSION: Hip offset (HO) restoration inaccuracy increased the risk of dislocation following primary THA. Multivariate radiologic restoration accuracy is critical for the prevention of dislocation and needs to be valued by surgeons.

Mechanistic insights into AMPK-SIRT3 positive feedback loop-mediated chondrocyte mitochondrial quality control in osteoarthritis pathogenesis.

Osteoarthritis (OA) is a major cause of disability in the elderly population and represents a significant public health problem and socioeconomic burden worldwide. However, no disease-modifying therapeutics are currently available for OA due to an insufficient understanding of the pathogenesis of this disability. As a unique cell type in cartilage, chondrocytes are essential for cartilage homeostasis and play a critical role in OA pathogenesis. Mitochondria are important metabolic centers in chondrocytes and contribute to cell survival, and mitochondrial quality control (MQC) is an emerging mechanism for maintaining cell homeostasis. An increasing number of recent studies have demonstrated that dysregulation of the key processes of chondrocyte MQC, which involve mitochondrial redox, biogenesis, dynamics, and mitophagy, is associated with OA pathogenesis and can be regulated by the chondroprotective molecules 5' adenosine monophosphate-activated protein kinase (AMPK) and sirtuin 3 (SIRT3). Moreover, AMPK and SIRT3 regulate each other, and their expression and activity are always consistent in chondrocytes, which suggests the existence of an AMPK-SIRT3 positive feedback loop (PFL). Although the precise mechanisms are not fully elucidated and need further validation, the current literature indicates that this AMPK-SIRT3 PFL regulates OA development and progression, at least partially by mediating chondrocyte MQC. Therefore, understanding the mechanisms of AMPK-SIRT3 PFL-mediated chondrocyte MQC in OA pathogenesis might yield new ideas and potential targets for subsequent research on the OA pathomechanism and therapeutics.

Prevalence and risk factors for prolonged opioid use after total joint arthroplasty: a systematic review, meta-analysis, and meta-regression.

PURPOSE: Opioids are a mainstay for pain management after total joint arthroplasty (TJA). The prevalence and risk factors for prolonged opioid use after TJA are important to understand to help slow the opioid epidemic. We aim to summarize and evaluate the prevalence and time trend of prolonged opioid use after TJA and pool its risk factors. METHODS: Following the preferred reporting items for systematic reviews and meta-analysis statement, we systematically searched PubMed, the Cochrane Library, and EMBASE, etc. from inception up to October 1, 2019. Cohort studies reporting risk factors for prolonged opioids use (≥ 3 months) after TJA were included. Studies characteristics, risk ratios (RR), and prevalence of prolonged opioid use were extracted and synthesized. RESULTS: A total of 15 studies were published between 2015 and 2019, with 416,321 patients included. 12% [95%CI 10-14%] of patients had prolonged opioid use after TJA and its time trend was associated with median enrollment years (P = 0.0013). Previous opioid use (RR = 1.73; P < 0.001), post-traumatic stress disorder (RR = 1.34; P < 0.001), benzodiazepine use (RR = 1.38; P < 0.001), tobacco abuse (RR = 1.26; P < 0.001), fibromyalgia (RR = 1.51; P < 0.001), and back pain (RR = 1.34; P < 0.001) were the largest effective risk factors for prolonged use of opioids. CONCLUSIONS: To our knowledge, this is the first meta-analysis determining the risk factors of prolonged opioid use and characterizing its rate and time trend in TJA. Understanding risk factors for patients with higher potential for prolonged opioids use can be used to implement appropriate management strategies, reduce unsafe opioid prescriptions, and decrease the risk of prolonged opioid use after TJA.

More pain and slower functional recovery when a tourniquet is used during total knee arthroplasty.

PURPOSE: Although a tourniquet can effectively control intraoperative blood loss and offer clear surgical field in total knee arthroplasty (TKA), its optimal usage has been controversial. The aim of this research was to perform a systematic review and meta-analysis to compare and explore the best application of a tourniquet in TKA. METHODS: MEDLINE, PubMed, EMBASE, the Cochrane Library, Wanfang database, and Web of Science were searched for randomized controlled trials (RCTs) comparing the four different strategies of tourniquet application in TKA. In Group I, a tourniquet was not used and was called the non-tourniquet (NT) group. In Group II, a tourniquet was only used during the cementation of implants and was called the specific duration tourniquet (SDT) group. In Group III, the tourniquet was only released before wound closure to control the bleeding sources and was called the majority duration tourniquet (MDT) group. In Group IV, a tourniquet was used throughout the procedure, from skin incision to wound closure and was called the whole duration tourniquet (WDT) group. RESULTS: Forty-six RCTs were included in this systematic review and meta-analysis. In a comparison between the NT and WDT groups (25 RCTs), intraoperative blood loss (IBL) (P = 0.0001) and range of motion (ROM) (P = 0.0001) were significantly increased in the NT group, while the visual analog score (VAS) (P = 0.0001), rate of deep vein thrombosis (DVT) (P = 0.01), and all complications (AC) (P = 0.0001) were significantly decreased in the NT group. In a comparison between the SDT and WDT groups (10 RCTs), IBL (P = 0.0001), TBL (P = 0.009), and ROM (P = 0.0001) were significantly increased in the SDT group, while thigh pain (P = 0.04) and the rate of DVT (P = 0.03) were significantly decreased in the SDT group. There were no significant differences between the MDT and WDT groups (12 RCTs) except for the rate of all complications (P = 0.01). CONCLUSION: Despite the decrease in IBL with a tourniquet, no difference was found in TBL. In conclusion, not using a tourniquet or only using it during the cementation of implants was preferable based on the faster functional recovery, lower rate of DVTs and complications compared with using a tourniquet throughout the TKA procedure. LEVEL OF EVIDENCE: I.

The incidence of symptomatic in-hospital VTEs in Asian patients undergoing joint arthroplasty was low: a prospective, multicenter, 17,660-patient-enrolled cohort study.

PURPOSE: The aim of this study was to determine the real incidence of symptomatic in-hospital venous thromboembolism (VTE) and identify risk factors for VTEs in Asian patients undergoing total hip (THA) and total knee arthroplasty (TKA). METHODS: A total of 17,660 patients (20,078 hips and knees) undergoing THA and TKA at 78 hospitals were enrolled. The composite incidence of symptomatic in-hospital DVT and PE was identified as the primary effectiveness outcomes. The primary safety outcomes were the incidences of postoperative complications, especially for major or minor bleeding. Secondary analyses were assessed to identify the risk factors for postoperative VTE. RESULTS: The overall rates of symptomatic in-hospital DVT in patients undergoing THA and TKA were 0.21% (19/9022) and 0.36% (31/8638), respectively. Symptomatic PE was confirmed in one TKA patient. Safety analysis showed that the incidence of bleeding during hospital stays in patients undergoing THA and TKA was 0.10% (18/17,660). Increased VTE risks were associated with old age, high BMI index, hypertension, cerebrovascular disease, history of venous thromboembolism and no medical prophylaxis usage. CONCLUSIONS: The incidence of symptomatic VTEs in Asian regions was low compared with that reported in studies targeting Western populations. Approximately 1 in 500 patients undergoing THA and approximately 1 in 300 patients undergoing TKA developed symptomatic VTEs prior to hospital discharge. Old age, high BMI, history of venous thromboembolism, hypertension, cerebrovascular disease, and no medication prophylaxis were risk factors identified in this study. LEVEL OF EVIDENCE: Prospective cohort study; Level 2.

Performance of Sequencing Assays in Diagnosis of Prosthetic Joint Infection: A Systematic Review and Meta-Analysis.

BACKGROUND: A prompt, accurate diagnosis of prosthetic joint infection (PJI) allows early treatment, and with identification of the causative organism, sensitive antibiotics could be applied. However, routine methods cannot identify the causative organism under certain circumstances. Gene sequencing assays have unique superiority in promptness and broad coverage of pathogens, but evidence of its accuracy is quite limited. METHODS: Of 247 citations identified for screening, 12 studies with 1965 patients in total were included. The diagnostic value of sequencing assays in PJI was systematically reviewed. Subgroup analysis was conducted to explore the source of heterogeneity. RESULTS: Pooled sensitivity was 0.81 (95% confidence interval [CI], 0.73-0.87); pooled specificity was 0.94 (95% CI, 0.91-0.97); positive likelihood ratio was 14.2 (95% CI, 8.7-23.4); negative likelihood ratio was 0.20 (95% CI, 0.14-0.29); and the area under the curve was 0.94 (95% CI, 0.18-1.00). The results of subgroup analysis revealed that antibiotics reduced the sensitivity of sequencing-based diagnosis compared with withholding antibiotics before sampling (0.71 vs 0.94). In another subgroup analysis, sequencing by synthesis (Illumina sequencing) had better specificity than other next-generation sequencing methods (0.963 vs 0.829) and specificity similar to time-consuming and laborious Sanger sequencing (0.963 vs 0.967). CONCLUSION: Sequencing assays had favorable diagnostic accuracy of PJI. When sequencing assays were applied to diagnosing PJI, an antibiotic-free interval before sampling may enhance the ability to detect the causative organism and, among next-generation sequencing methods, sequencing by synthesis seemed to have advantages over other methods in specificity.

Effect of knee flexion position and combined application of tranexamic acid on blood loss following primary total knee arthroplasty: a prospective randomized controlled trial.

PURPOSE: The aim of this study was to demonstrate the association between tranexamic acid (TXA)-combined application and knee flexion in the first 24 hour post-operatively that could reduce total blood loss and transfusion need in patients undergoing total knee arthroplasty (TKA), without sacrificing safety. METHODS: Ninety TKA patients were divided into three groups randomly: the flexion group: the knee was in 90° flexion position for the first 12 hour post-surgery and kept at 60°for the next 12 hour, combined with 1 g TXA topical and 1 g TXA intravenous application. The extension group: the knee was in fully extension position post-operatively, combined with topical and intravenous TXA application. The controlled group: the knee was in fully extension position post-operatively combined with single intravenous TXA application. The primary outcomes included blood loss variables and transfusion values. The secondary outcomes included post-operative hospital stay, knee flexion degree, complication rate, and hospital charge. RESULTS: The total blood loss and transfusion needs in the flexion group were significantly reduced in comparison with that in the extension group and controlled group. The post-operative knee flexion motion was significant higher in the flexion group than the other two groups. There was no difference among the three groups with regard to the rates of complications. CONCLUSIONS: Keeping the knee in flexion position combined with topical and intravenous TXA application in patients undergoing primary unilateral TKA significantly reduced post-operative bleeding and the transfusion rate compared with what was found after treatment with extension knee position or single intravenous TXA application. LEVEL OF EVIDENCE: Therapeutic Level I.

Comparison of cortisol and inflammatory response between aged and middle-aged patients undergoing total hip arthroplasty: a prospective observational study.

BACKGROUND: To investigate the differences in the perioperative serum cortisol, C-reactive protein (CRP) and interleukin-6 (IL-6) levels between aged and middle-aged patients undergoing total hip arthroplasty (THA). METHODS: Sixty patients (30 aged and 30 middle-aged) undergoing THA for osteoarthritis between August 2016 and January 2017 participated in this study. Blood samples were collected preoperatively and at 6 hours, 24 hours and 3 days after surgery to measure the cortisol, CRP and IL-6 concentrations. The clinical outcomes were assessed using the visual analogue scale (VAS) pain score and Harris hip score (HHS). RESULTS: No significant differences were found between the two groups before the operation in the cortisol, IL-6 and CRP levels; the VAS score; or the HHS. Cortisol was significantly lower at 6 hours after surgery in the aged group than in the middle-aged group (P < 0.05). IL-6 at 6 and 24 hours after surgery, CRP at 3 days after surgery and the VAS score at 6 and 24 hours after surgery in the aged group were significantly higher than those in the middle-aged group (P < 0.05). In the aged group, weak correlations were found between the cortisol concentration 6 hours after THA and the IL-6 level 24 hours after THA (r = -0.37, P = 0.04) and between the IL-6 level 6 hours after THA and the VAS score 24 hours after THA (r = 0.42, P = 0.02). CONCLUSION: Aged patients showed lower cortisol levels at 6 hours after surgery and higher IL-6 levels at 6 and 24 hours after surgery than middle-aged patients undergoing THA.

Correlations between inflammatory cytokines, muscle damage markers and acute postoperative pain following primary total knee arthroplasty.

BACKGROUND: Despite the success of total knee arthroplasty (TKA) in reducing knee pain and improving functional disability, the management of acute postoperative pain is still unsatisfactory. This study was aimed to quantitatively analyze the possible correlations between inflammatory cytokines, muscle damage markers and acute postoperative pain following primary TKA. METHODS: Patients scheduled for unilateral primary TKA were consecutively included, the serial changes of the numerical rating scale (NRS) at rest (NRSR) and at walking (NRSW), serum inflammatory cytokines and muscle damage markers were assessed before surgery (T0) and at postoperative day 1, 2, 3 and 5 (T1-T4, respectively); while pain disability questionnaire (PDQ) and synovial fluid inflammatory cytokines were evaluated at T0. The correlations between inflammatory cytokines, muscle damage markers and pain scores were examined, and Bonferroni correction was applied for multiple comparisons. RESULTS: Ninety six patients were included for serum markers and pain evaluations at T0-T4, while 54 (56.25%) for synovial fluid cytokines at T0. The NRSR at T1 and T2 were positively correlated with preoperative NRSW, while the NRSW at T1 to T4 were positively correlated with preoperative NRSR, NRSW and PDQ (all p < 0.05). The NRSR was positively correlated with serum PGE2, IL-6, and CK at T1; the NRSW was positively correlated with serum CRP at T1, with PGE2 and IL-6 at T1 to T3, with CK at T2 and T4, and with Mb and LDH at T1 to T4 (all p < 0.003). Meanwhile, positive correlations were observed between preoperative NRSW and synovial fluid PGE2, IL-6, IL-8, or TNF-α, as well as between PDQ and PGE2 (all p < 0.003), but no associations between postoperative pain scores and preoperative synovial fluid cytokines was found (all p ≥ 0.003). Additionally, the NRSR at T1 and T2, and NRSW at T1 to T4 were positively correlated with body mass index (all p < 0.05). CONCLUSIONS: Serum inflammatory cytokines and muscle damage markers are positively correlated with acute postoperative pain following primary TKA, and the key cytokines (CRP, PGE2, and IL-6) and markers (Mb, CK and LDH) may serve as the targets for developing novel analgesic strategies.

WITHDRAWN: The Congruence and Joint Space Width of the Lateral Compartment Can Be Restored After Medial Unicompartmental Knee Arthroplasty.

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No clear benefit or drawback to the use of closed drainage after primary total knee arthroplasty: a systematic review and meta-analysis.

BACKGROUND: Closed drainage after primary total knee arthroplasty (TKA) has been used routinely for many decades, but controversies have arisen in recent years. The purposes of this study were to compare the clinical outcomes of closed drainage with nondrainage after primary TKA; and to assess the benefit and drawback of closed drainage. METHODS: Electronic databases (PubMed/Medline, CENTRAL, Embase and Web of Science) were systematically searched for randomised controlled trials (RCTs) that investigated the efficacy and risks of closed drainage after primary TKA. Two investigators independently reviewed studies for eligibility, assessed the risk of bias and extracted the data. A meta-analysis was then performed using Review Manager Software. RESULTS: Twelve RCTs totalling 889 TKAs were identified. No significant differences in infection rate or blood loss were found between the closed drainage and nondrainage TKAs, and there was also no significant difference in haematoma formation, deep venous thrombosis, postoperative VAS score or range of motion between the two groups. CONCLUSIONS: There appears to be no clear benefit or drawback to the use of closed drainage after primary TKA. Improving the use of closed drainage might provide better outcomes.

The Efficacy and Safety of Combination of Intravenous and Topical Tranexamic Acid in Revision Hip Arthroplasty: A Randomized, Controlled Trial.

BACKGROUND: Revision total hip arthroplasty (THA) is associated with substantial blood loss and a high probability of blood transfusion in the perioperative period. This study aimed to evaluate the efficacy and safety of combination of intravenous (IV) and topical tranexamic acid (TXA) in revision THA. METHODS: Eighty-four consecutive patients undergoing revision THA were randomized into combined group and IV-TXA group. Patients in the combined group were given intravenously 15 mg/kg TXA as a preoperative, and topical TXA solution was applied at a concentration of 3 g TXA per 100-mL saline during the different procedure points. Patients in the IV-TXA group were given intravenously 15 mg/kg TXA alone. RESULTS: The mean total blood loss, drainage volume, and maximum hemoglobin drop were significantly lower in the combined group than the IV-TXA group (P < .001, P < .001, P < .001, respectively). Compared with the IV-TXA group, the amount of blood transfusions and number of blood transfusions required were decreased dramatically in the combined group (P = .027, P < .001, respectively). One deep vein thrombosis and 4 calf muscular vein thrombosis in the combined group and 3 calf muscular vein thrombosis in the IV-TXA were detected by the Doppler ultrasound. No pulmonary embolism was observed and no significant differences were found in other complications between the 2 groups. CONCLUSION: This study showed that combined administration of IV and topical TXA in revision THA can effectively decrease total blood loss and number of blood transfusions required without increasing the risk of deep vein thrombosis or/and pulmonary embolism compared with IV-TXA alone.

Expression of miRNA-140 in Chondrocytes and Synovial Fluid of Knee Joints in Patients with Osteoarthritis.

Objective To investigate the expression of miRNA-140 in chondrocytes and synovial fluid of osteoarthritis (OA) patients, and explore the relationship between the miRNA-140 expression and OA severity.Methods This study enrolled 30 OA patients who underwent total knee arthroplasty for chondrocytes sampling and 30 OA patients who underwent intra-articular injection for synovial fluid sampling. All OA patients were grouped into mild [Kellgren and Lawrence (KL) grade 1-2], moderate (KL grade 3) and severe (KL grade 4), with 10 in each subgroups for each sampling purposes. 7 non-OA patients and 10 patients with knee injury were collected for cartilage and synovial fluid sampling respectively as control groups. Chondrocytes were isolated from the cartilage tissue and cultured in vitro. Quantitative real time PCR for miRNA-140 in chondrocytes and synovial fluid were performed, and the U6 snRNA was used as internal control. The expression difference of miRNA-140 among groups and correlation between the expression and the KL grade of OA were analysed using one-way ANOVA and Spearman test respectively. Results The expression of miRNA-140 in chondrocytes of knees in OA patients was reduced than that in normal knees, and the between-group difference was statistically significant (F=305.464, P<0.001). miRNA-140 could be detected in synovial fluid of both normal knees and OA knees, its relative expression level was reduced in synovial fluid of OA group compared with normal group, and the between-group difference was statistically significant as well (F=314.245, P<0.001). The relative expression level of miRNA-140 in both chondrocytes and synovial fluid were negatively correlated with the KL grade of OA(r=-0.969, P<0.001; r=-0.970, P<0.001). Conclusion miRNA-140 could be detected in chondrocytes and synovial fluid of OA patients, and its expression was negatively correlated with the severity of OA.

The influence of body mass index on the outcomes of primary total knee arthroplasty.

PURPOSE: The body mass index (BMI) is widely recognized as a prognostic factor in multiple operations; however, the relationship between the BMI and outcomes following total knee arthroplasty (TKA) is extensively debated. We aimed to evaluate the effect of the BMI at different cutoff values on the outcomes following primary TKA. METHODS: Electronic databases (PubMed/Medline, CENTRAL, Embase and Web of Science) were systematically searched for studies investigating the association between the BMI and outcomes following primary TKA. Two investigators independently reviewed studies for eligibility, assessed the study quality using the Newcastle-Ottawa Scale and extracted the data. A meta-analysis was performed using Review Manager software. RESULTS: Twenty-eight articles including a total of 20,988 TKAs were identified. The postoperative Knee Society Score appeared to trend lower in obese (BMI ≥ 30 kg/m(2)) patients than in non-obese (BMI < 30 kg/m(2)) patients. The meta-analysis showed that revision with follow-up ≥5 years, any infection, superficial infection and deep vein thrombosis occurred statistically more frequently in obese patients, whereas a deep infection occurred statistically more frequently in morbidly obese (BMI ≥ 40 kg/m(2)) patients than in non-obese patients. No differences in aseptic loosening with follow-up ≥5 years, pulmonary embolism and perioperative mortality rates were found between obese and non-obese patients. CONCLUSIONS: Patients with a BMI ≥ 30 kg/m(2) are at a higher risk of lower functional scores and developing complications following primary TKA. It appears reasonable to encourage obese patients to lose weight before selective TKA. LEVEL OF EVIDENCE: Prognostic study, Level III.

Accuracy of a Simple Digital Templating in Primary Uncemented Total Hip Arthroplasty.

OBJECTIVE: To introduce a simple preoperative digital templating in uncemented total hip arthroplasty (THA) and to determine its accuracy for preoperative size selection of the prostheses. METHODS: A prospective study of digital planned THAs was performed on 90 hips with different types of prostheses from August 2013 to Angust 2014. The plastic templates of different types of prostheses were scanned for desired digital templating and the scanned images were then processed to the transparent, digital templates using Photoshop software. We calibrated the scales of the digital templates with the preoperative radiographs, and then selected the right size of the component. The preoperatively digital planned component sizes were compared to the actual sizes used in the operation, as well as the preoperatively traditional planned sizes. RESULTS: In either cup or stem templating, no difference was found among the groups with different types of prostheses, and the accuracy of digital templating was statistically higher than traditional templating. In cup templating, digital planned and implanted cup sizes were identical in 43.33% of the cases, 78.89% of the cup sizes were predicted within 1 size (± 2mm) and 95.56% were predicted within 2 sizes (± 4 mm), all significantly higher than the results of traditional planned sizes (30.00%, P=0.044; 61.11%, P=0.007; 82.22%, P=0.004). The exact femoral stem size was predicted in 40.00% of cases using the digital templating, 84.44% of stem sizes were predicted within 1 size, and 93.33% within 2 sizes, better than using traditional templating (25.56%, P=0.028; 53.33%, P<0.001; 77.77%, P=0.003). CONCLUSION: This simple digital preoperative templating is an accurate and reproducible process to preoperatively predict the implant size of uncemented THA.

Association between nighttime sleep duration and quality with knee osteoarthritis in middle-aged and older Chinese: A longitudinal cohort study.

BACKGROUND: The association between nighttime sleep duration and sleep quality with the risk of knee osteoarthritis (OA) remains unclear. This study aimed to examine the longitudinal association among middle-aged and older adults in China. METHODS: The data used in this study were obtained from the China Health and Retirement Longitudinal Study (CHARLS) surveys conducted in 2011 and 2015. Nighttime sleep duration was categorized into five groups: <6 h, 6 to <7 h, 7 to <8 h, 8 to <9 h, and ≥9 h/night. Sleep quality was assessed by restless days in the past week (<1, 1-2, 3-4, and 5-7 days/week). Multivariate logistic regression models were used to assess the association between sleep duration and quality with incident knee OA. RESULTS: A total of 11,114 participants who did not have knee OA at baseline were enrolled in this study. After 4 years of follow-up, the overall incidence of knee OA was 8.07 %. Compared to 7 to <8 h of sleep duration, short sleep duration (<6 h/night) was associated with a significantly increased risk of incident knee OA in the fully adjusted model [odds ratio (OR) =1.73, 95 % confidence interval (CI): 1.33-2.25]. Additionally, participants with 5-7 sleep restless days/week were associated with significantly increased risk of incident knee OA (OR = 1.88, 95 % CI: 1.48-2.38). CONCLUSIONS: Short nighttime sleep duration and poor sleep quality are associated with increased risk of incident knee OA.

The Negative Impacts of Sarcopenia on Primary Total Knee Arthroplasty under the Enhanced Recovery after Surgery Protocol.

OBJECTIVE: Sarcopenia, as an emerging public health concern, has been associated with postoperative adverse outcomes in various surgical procedures. However, the evidence regarding the impacts of sarcopenia on total knee arthroplasty (TKA) remained limited. This study aimed to assess the impacts of sarcopenia on primary TKA based on the enhanced recovery after surgery (ERAS) protocol. METHODS: This retrospective study included 291 patients who received unilateral TKA from October 2017 to May 2018 in our institution. Sarcopenia was diagnosed based on the algorithm of Asian Working Group for Sarcopenia 2019. The handgrip strength was measured using a handheld dynamometer and the muscle mass was estimated by a previously validated anthropometric equation. Patients were classified into sarcopenia group and non-sarcopenia group. The outcomes included complications, postoperative length of stay (LOS), total hospitalization cost, operative time, total estimated blood loss, blood transfusion rate, and the 12-item forgotten joint score (FJS-12) at the follow-up. The propensity score matching (PSM) was used to adjust confounding factors. We compared continuous variables using Student's t-test and the Wilcoxon Mann-Whitney U test for normal and non-normal distributions, respectively, and categorical variables with chi-square tests. RESULTS: Of the 291 patients, 58 (19.9%) patients were identified as having sarcopenia. After PSM, each group matched 42 patients. All matched patients were followed-up at least 5 years. Patients with sarcopenia had higher rates of surgical complications compared to the non-sarcopenia group (p = 0.019), and no significant difference was observed in 30-day readmission, and periprosthetic joint infection. The sarcopenia group had significantly longer LOS (p = 0.038), higher total hospitalization (p = 0.015) than the non-sarcopenia group. For the FJS-12 scores at follow-up, patients with sarcopenia had significantly higher scores than the non-sarcopenia group (p = 0.024). CONCLUSION: Our findings indicated sarcopenia may be a risk factor for postoperative complications, prolonged LOS, increased hospitalization cost and reduced patient satisfaction.

Association between handgrip strength weakness and asymmetry with incident hip fracture among older Chinese adults.

BACKGROUND: To evaluate the association between handgrip strength (HGS) weakness and asymmetry with incident hip fracture among older Chinese adults. METHODS: Data was obtained from the 2011 and 2015 waves of the China Health and Retirement Longitudinal Study (CHARLS). HGS weakness was defined as maximal HGS 〈 28 kg in men and < 18 kg in women. HGS asymmetry was defined as the HGS ratio < 0.9 or 〉 1.1. Participants were categorized into normal HGS, weakness only, asymmetry only, and both weakness and asymmetry. Given the sex differences in HGS, the association between HGS weakness and asymmetry was analyzed by sex using the multivariable logistic regression models. RESULTS: A total of 4789 participants aged ≥ 60 years old without hip fracture at baseline were included in the final analysis. Over the four-year follow-up, there were 152 (3.17 %) participants having incident hip fractures, of which 69 (2.90 %) were men and 83 (3.45 %) were women. Compared to the normal group, men with both weakness and asymmetry had a significantly higher risk of incident hip fracture in the fully adjusted model (adjusted odds ratio (OR): 2.31, 95 % confidence interval (CI):1.17-4.52). There was no significant association between HGS asymmetry and weakness with hip fracture in women. CONCLUSIONS: Our findings indicated that among the Chinese population, men with both HGS weakness and asymmetry were associated with increased odds of hip fracture, while no significant association was observed in women.