The Effect of Passive Smoking on Early Clinical Outcomes After Total Knee Arthroplasty Among Female Patients

Feasibility and Mechanical Strength Evaluation of New Customized Implants for Tibial Plateau Fractures Fixation

BACKGROUND AND OBJECTIVE

Customized implants could improve the capture of fracture fragments for strengthened stability of tibial plateau fractures (TPFs) fixation. This study aimed to validate the feasibility of customized implants through optimized manufacturing within a clinically acceptable timeframe and evaluate the mechanical strength of customized internal implants through finite element analysis.

METHODS

A retrospective was conducted. From May 1, 2023, to June 1, 2023, 10 patients with TPFs were treated at our hospital using various new internal fixation systems combined with customized technology. The indicators of patients characteristics, operation, and follow-up were collected, such as the cause of trauma, fresh or old, fracture classification, blood loss, Lysholm score, EQ-5D-3L score, and so on. Additionally, we created a Schatzker IV TPF model with two separated fragments in the medial to compare the biomechanical strength and directional deformation between standard medial dual plates (MDPs) and medial customized plate (MCP).

RESULTS

The study found that the entire process of implant fabrication can be completed within a clinically acceptable timeframe of 3-4 days. We designed specific types of plates for different types of fractures, such as semi-circumferential plates for lateral TPFs, γ-type plates for medial TPFs, and pistol-type and wing-type plates for posterior TPFs. Follow-up analysis showed operative times of 1.37 ± 0.58 h, intraoperative blood loss of 260 ± 179.20 mL, and favorable functional outcomes: Lysholm score 88.6 ± 4.93, knee ROM 103.5° ± 11.56°, and EQ-5D-3L score 0.87 ± 0.47. Additionally, the γ-type plate showed comparable strength to the MDPs system via finite element analysis and demonstrated a more vital ability to resist the separation of fracture fragments, with the maximum displacement of MDPs (0.61878 mm) 2.4 times higher than that of MCP (0.26124 mm).

CONCLUSIONS

Using customized internal fixation systems provided solutions to challenges of complex fractures, within a clinically acceptable timeframe of 3-4 days. Notably, the study showed that the strength of customized internal fixation systems of γ-shaped plate was comparable to that of conventional implants. This innovative approach offered a new avenue for managing TPFs and even complex limb fractures.

Evaluating Surgeon-influenced Factors for Total Knee Arthroplasty Value-based Reimbursement

INTRODUCTION

Clinical outcome measures used under value-based reimbursement models require risk stratification of patient demographics and medical history. Only certain perioperative patient factors may be influenced by the surgeon. The study evaluated surgeon-influenced modifiable factors associated with achieving literature-defined KOOS score thresholds to serve as the foundation of the newly established alternative payment models for total knee arthroplasties (TKA).

METHODS

We retrospectively reviewed a consecutive cohort of 4,324 patients undergoing TKA. Surgeon-influenced modifiable risk factors included thromboprophylaxis with aspirin, tourniquet use, tranexamic acid (TXA), body mass index, smoking, alcohol or illicit drug use, surgical time, length of stay (LOS), and bilateral TKA. Outcomes included complications, 90-day readmissions, discharge disposition, knee injury and osteoarthritis outcome score (KOOS) minimal clinically important difference (MCID), KOOS patient acceptable symptom state (PASS), and short form-12 (SF-12) MCID achievement. A bivariate analysis and regression were built to determine the likelihood of primary outcomes based on modifiable factors.

RESULTS

Bilateral TKA was associated with a higher odds ratio (OR) for home discharge (OR = 5.40, P < 0.001), KOOS MCID (OR = 2.60, P < 0.001), PASS (OR = 2.4, P ≤ 0.001), and SF-12 PCS MCID achievement (OR = 3.21, P < 0.001). Similarly, LOS was inversely associated with KOOS MCID (OR = 0.88, P = 0.002) and PASS (OR = 0.81, P < 0.001) but directly associated with home discharge (OR = 2.5, P ≤ 0.001) in-hospital complications (OR = 1.50, P < 0.001) and 90-day readmissions (OR = 1.23, P = 0.005). The KOOS MCID and PASS achievement was positively influenced by TXA (OR = 1.33, P = 0.008; OR = 1.29, P = 0.020) use and negatively influenced by aspirin use (OR = 0.68, P = 0.013; OR = 0.73, P = 0.040). In-hospital opioid use was an independent risk factor for not achieving SF-12 MCS MCID (OR = 0.56, P = 0.006).

CONCLUSION

In this study, modifiable perioperative variables, such as TXA, aspirin use, opioid use, LOS, and bilateral TKA, were found to markedly increase quality metrics threshold achievement and should be considered as risk variables in the current value-based care models. Future studies should investigate the effect of modifiable risk factors on quality metrics to build new risk adjustment tools that incentivize patient perioperative optimization.

The effect of tobacco use on clinical outcomes in total knee arthroplasty patients

Introduction

Previous research has established that smoking significantly increases the complication rate of total knee arthroplasty (TKA). Risk of infection, prosthetic loosening, fractures, wound healing issues, and revisions are increased in smokers, but research is limited on the long-term clinical outcomes of pain, range of motion, stability, and functionality between smokers, nonsmokers, and former smokers, specifically utilizing Knee Society Scores (KSS).

Methods

This was a retrospective chart review of primary TKA patients (n = 203) at a single university hospital. The patients were divided by smoking status: nonsmoker, current smoker, or former smoker. One-way analysis of variance with associated f ratios was performed to assess variance in KSS by smoking status over time. Relative risk ratio analyses were employed to assess patients' predictive risk of acquiring postoperative infection and requiring additional surgery following TKA based on smoking status.

Results

Postoperative KSS were significantly lower in the smoker group compared to nonsmokers and former smokers at 6 weeks and 1 year. For every 20 months a former smoker used tobacco, an approximate 1-point decrease in KSS was expected. The relative risk ratios for postoperative infection rates and patients requiring additional surgery were 2.13 and 1.44, respectively, when current smokers were compared to nonsmokers.

Conclusions

This analysis found that current smokers had lower KSS and higher infection rates following TKA when compared to nonsmoking controls. In addition, increased duration of smoking was correlated with poorer outcomes within the former smoker group.

Development of machine learning models for predicting depressive symptoms in knee osteoarthritis patients

Knee osteoarthritis (KOA) combined with depressive symptoms is prevalent and leads to poor outcomes and significant financial burdens. However, practical tools for identifying at-risk patients remain limited. A robust prediction model is needed to address this gap. This study aims to develop and validate a predictive model to identify KOA patients at risk of developing depressive symptoms. The China Health and Retirement Longitudinal Survey (CHARLS) data were used for model development and the Osteoarthritis Initiative (OAI) for external validation. 18 potential predictors were selected using LASSO regression. 4 machine learning models-logistic regression, decision tree, random forest, and artificial neural network-were developed. Model performance was assessed using the area under the operating characteristic curve (AUC), calibration curves, and decision curve analysis. The most important features were extracted from the optimal model on external validation. A total of 469 individuals were included, with 70% used for training and 30% for testing. The random forest model achieved the best performance, with an AUC of 0.928 in the test set, outperforming logistic regression (AUC 0.622), decision tree (AUC 0.611), and neural network models (AUC 0.868). External validation revealed an AUC of 0.877 (95% CI: 0.864-0.889) for the adjusted random forest model. Pain severity was the most significant predictor, followed by the five-time sit-to-stand test (FTSST) and sleep problems. This study is the first in China to apply a predictive model for depressive symptoms in KOA patients, offering a practical tool for early risk identification using routinely available data.

Hypoalbuminemia is Highly Prevalent in Patients with Periprosthetic Joint Infection and Strongly Associated with Treatment Failure

OBJECTIVE

The role of hypoalbuminemia throughout the course of chronic periprosthetic joint infection (PJI) remains poorly understood. This study aimed to determine the prevalence and risk factors of hypoalbuminemia in periprosthetic joint infection (PJI) patients and to explore the association between hypoalbuminemia and treatment outcomes.

METHODS

This retrospective cohort study included 387 PJI cases who underwent two-stage exchange arthroplasty between January 2007 and August 2020, of which 342 were reimplanted. The mean follow-up period was 7.9 years. Multivariate logistic regression analyses were performed to identify risk factors for hypoalbuminemia and to assess the effect of hypoalbuminemia at 1st- and 2nd-stage exchange on the treatment outcome. Furthermore, the impact of dynamic changes in hypoalbuminemia was investigated.

RESULTS

The prevalence of hypoalbuminemia at 1st- and 2nd-stage exchange was 22.2% and 4.7%, respectively. Patients with age ≥ 68 years and those with isolation of Staphylococcus aureus, Streptococcus, or Gram-negative bacteria exhibited a higher risk of hypoalbuminemia. Hypoalbuminemia at 1st-stage was significantly related to treatment failure (OR = 3.3), while hypoalbuminemia at 2nd-stage raised the OR to 10.0. Patients with persistent hypoalbuminemia at both the 1st- and 2nd-stage exchanges had a significantly higher rate of treatment failure than patients with hypoalbuminemia at the 1st-stage but normal albumin levels at the 2nd-stage exchange (55.6% vs 20.0%, p = 0.036).

CONCLUSION

One in five patients with chronic PJI exhibits hypoalbuminemia. Hypoalbuminemia is more likely to develop in patients of advanced age and those infected by specific highly virulent organisms. Also, our results highlight the close association between hypoalbuminemia and treatment outcomes.

Injectable and in situ foaming shape-adaptive porous Bio-based polyurethane scaffold used for cartilage regeneration

Irregular articular cartilage injury is a common type of joint trauma, often resulting from intense impacts and other factors that lead to irregularly shaped wounds, the limited regenerative capacity of cartilage and the mismatched shape of the scaffods have contributed to unsatisfactory therapeutic outcomes. While injectable materials are a traditional solution to adapt to irregular cartilage defects, they have limitations, and injectable materials often lack the porous microstructures favorable for the rapid proliferation of cartilage cells. In this study, an injectable porous polyurethane scaffold named PU-BDO-Gelatin-Foam (PUBGF) was prepared. After injection into cartilage defects, PUBGF forms in situ at the site of the defect and exhibits a dynamic microstructure during the initial two weeks. This dynamic microstructure endows the scaffold with the ability to retain substances within its interior, thereby enhancing its capacity to promote chondrogenesis. Furthermore, the chondral repair efficacy of PUBGF was validated by directly injecting it into rat articular cartilage injury sites. The injectable PUBGF scaffold demonstrates a superior potential for promoting the repair of cartilage defects when compared to traditional porous polyurethane scaffolds. The substance retention ability of this injectable porous scaffold makes it a promising option for clinical applications.

Decellularized laser micro-patterned osteochondral implants exhibit zonal recellularization and self-fixing for osteochondral regeneration in a goat model

Background

Osteochondral regeneration has long been recognized as a complex and challenging project in the field of tissue engineering. In particular, reconstructing the osteochondral interface is crucial for determining the effectiveness of the repair. Although several artificial layered or gradient scaffolds have been developed recently to simulate the natural interface, the functions of this unique structure have still not been fully replicated. In this paper, we utilized laser micro-patterning technology (LMPT) to modify the natural osteochondral "plugs" for use as grafts and aimed to directly apply the functional interface unit to repair osteochondral defects in a goat model.

Methods

For in vitro evaluations, the optimal combination of LMPT parameters was confirmed through mechanical testing, finite element analysis, and comparing decellularization efficiency. The structural and biological properties of the laser micro-patterned osteochondral implants (LMP-OI) were verified by measuring the permeability of the interface and assessing the recellularization processes. In the goat model for osteochondral regeneration, a conical frustum-shaped defect was specifically created in the weight-bearing area of femoral condyles using a customized trephine with a variable diameter. This unreported defect shape enabled the implant to properly self-fix as expected.

Results

The micro-patterning with the suitable pore density and morphology increased the permeability of the LMP-OIs, accelerated decellularization, maintained mechanical stability, and provided two relative independent microenvironments for subsequent recellularization. The LMP-OIs with goat's autologous bone marrow stromal cells in the cartilage layer have securely integrated into the osteochondral defects. At 6 and 12 months after implantation, both imaging and histological assessments showed a significant improvement in the healing of the cartilage and subchondral bone.

Conclusion

With the natural interface unit and zonal recellularization, the LMP-OI is an ideal scaffold to repair osteochondral defects especially in large animals.

The translational potential of this article

These findings suggest that such a modified xenogeneic osteochondral implant could potentially be explored in clinical translation for treatment of osteochondral injuries. Furthermore, trimming a conical frustum shape to the defect region, especially for large-sized defects, may be an effective way to achieve self-fixing for the implant.

Development and validation of a nomogram for predicting sever cancer-related fatigue in patients with cervical cancer

OBJECTIVE

Cancer-related fatigue (CRF) has been considered the biggest influencing factor for cancer patients after surgery. This study aimed to develop and validate a nomogram for severe cancer-related fatigue (CRF) patients with cervical cancer (CC).

METHODS

A cross-sectional study was conducted to develop and validate a nomogram (building set = 196; validation set = 88) in the Department of Obstetrics and Gynecology of a Class III hospital in Shenyang, Liaoning Province. We adopted the questionnaire method, including the Cancer Fatigue Scale (CFS), Medical Uncertainty in Illness Scale (MUIS), Medical Coping Modes Questionnaire (MCMQ), Multidimensional Scale of Perceived Social Support (MSPSS), and Sense of Coherence-13 (SOC-13). Binary logistic regression was used to test the risk factors of CRF. The R4.1.2 software was used to develop and validate the nomogram, including Bootstrap resampling method, the ability of Area Under Curve (AUC), Concordance Index (C-Index), Hosmer Lemeshow goodness of fit test, Receiver Operating Characteristic (ROC) curve, Calibration calibration curve, and Decision Curve Analysis curve (DCA).

RESULTS

The regression equation was Logit(P) = 1.276-0.947 Monthly income + 0.989 Long-term passive smoking - 0.952 Physical exercise + 1.512 Diagnosis type + 1.040 Coping style - 0.726 Perceived Social Support - 2.350 Sense of Coherence. The C-Index of the nomogram was 0.921 (95% CI: 0.877∼0.958). The ROC curve showed the sensitivity of the nomogram was 0.821, the specificity was 0.900, and the accuracy was 0.857. AUC was 0.916 (95% CI: 0.876∼0.957). The calibration showed that the predicted probability of the nomogram fitted well with the actual probability. The DCA curve showed when the prediction probability was greater than about 10%, the benefit of the nomogram was positive. The results in the validation group were similar.

CONCLUSION

This nomogram had good identifiability, accuracy and clinical practicality, and could be used as a prediction and evaluation tool for severe cases of clinical patients with CC.

Evaluation of risk factors for surgical site infections in osteoarthritis patients undergoing total knee arthroplasty

This research sought to delineate risk factors associated with surgical site infections (SSIs) post-total knee arthroplasty (post-TKA) in elderly osteoarthritis patients, aiming to enhance post-surgical outcomes. A retrospective examination was conducted on a cohort of 650 elderly patients who underwent unilateral TKA between January 2018 and August 2022. Data procurement was from the hospital's Electronic Health Record, and a comprehensive statistical evaluation was performed using IBM SPSS Statistics version 24.0. Both univariate and multivariate techniques assessed a spectrum of risk determinants such as age, body mass index (BMI), coexisting medical conditions and surgical variables. The univariate examination spotlighted age, BMI, diabetes prevalence, chronic corticosteroid consumption and American Society of Anesthesiologists (ASA) physical status classification as notable predictors of SSIs. The multivariate logistic regression pinpointed age, BMI, history of smoking and diabetes diagnosis as salient risk attributors for post-TKA infections. Concurrently, parameters like ASA classification, surgical duration and intraoperative haemorrhage further enriched the risk landscape. Geriatric patients undergoing TKA for knee osteoarthritis manifest a tangible infection susceptibility post-surgery. Precision interventions concentrating on amendable risk components, including meticulous preoperative evaluations and strategic postoperative care, are imperative to attenuate SSI incidence, thereby amplifying surgical efficacy and optimizing patient recuperation trajectories.

Identification of immune infiltration and immune-related biomarkers of periprosthetic joint infection

BACKGROUND

The immune response associated with periprosthetic joint infection (PJI) is an emerging but relatively unexplored topic. The aim of this study was to investigate immune cell infiltration in periprosthetic tissues and identify potential immune-related biomarkers.

METHODS

The GSE7103 dataset from the GEO database was selected as the data source. Differentially expressed genes (DEGs) and significant modular genes in weighted correlation network analysis (WGCNA) were identified. Functional enrichment analysis and transcription factor prediction were performed on the overlapping genes. Next, immune-related genes from the ImmPort database were matched. The protein-protein interaction (PPI) analysis was performed to identify hub genes. CIBERSORTx was used to evaluate the immune cell infiltration pattern. Spearman correlation analysis was used to evaluate the relationship between hub genes and immune cells.

RESULTS

A total of 667 DEGs were identified between PJI and control samples, and 1847 PJI-related module genes were obtained in WGCNA. Enrichment analysis revealed that the common genes were mainly enriched in immune and host defense-related terms. TFEC, SPI1, and TWIST2 were the top three transcription factors. Three hub genes, SDC1, MMP9, and IGF1, were identified in the immune-related PPI network. Higher levels of plasma cells, CD4+ memory resting T cells, follicular helper T cells, resting mast cells, and neutrophils were found in the PJI group, while levels of M0 macrophages were lower. Notably, the expression of all three hub genes correlated with the infiltration levels of seven types of immune cells.

CONCLUSION

The present study revealed immune infiltration signatures in the periprosthetic tissues of PJI patients. SDC1, MMP9, and IGF1 were potential immune-related biomarkers for PJI.

American Academy of Orthopaedic Surgeons Clinical Practice Guideline Summary of Surgical Management of Osteoarthritis of the Knee

The Surgical Management of Osteoarthritis of the Knee Evidence-Based Clinical Practice Guideline is based on a systematic review of published studies for surgical management of osteoarthritis of the knee in skeletally mature patients. This guideline contains 16 recommendations and seven options to assist orthopaedic surgeons and all qualified physicians with the surgical management of patients with osteoarthritis of the knee based on the best current available evidence. It is also intended to serve as an information resource for professional healthcare practitioners and developers of practice guidelines and recommendations. In addition to providing pragmatic practice recommendations, this guideline also highlights gaps in the literature and informs areas for future research and quality measure development.

The Clinical Impact of Metagenomic Next-Generation Sequencing for the Diagnosis of Periprosthetic Joint Infection

BACKGROUND

Synovial fluid metagenomic next-generation sequencing was introduced into the diagnosis of periprosthetic joint infection (PJI) in recent years. However, the clinical impact of mNGS remains unknown. Therefore, we performed a prospective cohort study to evaluate the clinical impact of mNGS for PJI diagnosis.

MATERIALS AND METHODS

Between April 2019 and April 2021, a total of 201 patients with suspected PJI were recruited in a high-volume PJI revision center. All patients underwent joint aspiration before surgeries and the obtained synovial fluids were sent to tests for the diagnosis of PJI. Based on the clinical evaluation of these patients, the patients were categorized into three groups: Group A: the mNGS reports were not acted upon. Group B: mNGS confirmed the standard diagnostic tests of PJI and generated identical clinical impact compared to standard diagnostic tests. Group C: mNGS results guided clinical therapy. Then, the concordance between synovial mNGS and cultures was analyzed. After that, multivariate regressions were performed to explore the "targeted populations" of mNGS tests.

RESULTS

A total of 107 patients were diagnosed with PJI based on the 2014 MSIS criteria and there were 33, 123, 45 patients in the group A, B, C respectively. The predictive factors of mNGS inducing clinical impact compared to standard diagnostic tests were negative culture results (adjusted OR: 5.88), previous history of joint infection (adjusted OR: 5.97), polymicrobial PJI revealed by culture (adjusted OR: 4.39) and PJI identified by MSIS criteria (adjusted OR: 17.06).

CONCLUSION

When standard diagnostic tests for PJI were performed, about 22% of synovial fluid mNGS tests can change the treatment protocols built on standard diagnostic tests and affect the clinical practice. Thus, the use of synovial fluid mNGS in some "target" populations is more valuable compared to others such as patients with previous joint infection, polymicrobial PJI, and culture-negative PJI.

EVIDENCE LEVEL

Level I.

Incidence, associated factors, and outcomes of acute kidney injury following placement of antibiotic bone cement spacers in two-stage exchange for periprosthetic joint infection: a comprehensive study

BACKGROUND

Two-stage exchange with placement of antibiotic cement spacer (ACS) is the gold standard for the treatment of chronic periprosthetic joint infection (PJI), but it could cause a high prevalence of acute kidney injury (AKI). However, the results of the current evidence on this topic are too mixed to effectively guide clinical practice.

METHODS

We retrospectively identified 340 chronic PJI patients who underwent the first-stage exchange with placement of ACS. The Kidney Disease Improving Global Outcomes guideline was used to define postoperative AKI. Multivariate logistic analysis was performed to determine the potential factors associated with AKI. Furthermore, a systematic review and meta-analysis on this topic were conducted to summarize the knowledge in the current literature further.

RESULTS

In our cohort, the incidence of AKI following first-stage exchange was 12.1%. Older age (per 10 years, OR= 1.509) and preoperative hypoalbuminemia (OR= 3.593) were independent predictors for postoperative AKI. Eight AKI patients progressed to chronic kidney disease after 90 days. A meta-analysis including a total of 2525 PJI patients showed the incidence of AKI was 16.6%, and AKI requiring acute dialysis was 1.4%. Besides, host characteristics, poor baseline liver function, factors contributing to acute renal blood flow injury, and the use of nephrotoxic drugs may be associated with the development of AKI. However, only a few studies supported an association between antibiotic dose and AKI.

CONCLUSION

AKI occurs in approximately one out of every six PJI patients undergoing first-stage exchange. The pathogenesis of AKI is multifactorial, with hypoalbuminemia could be an overlooked associated factor. Although the need for acute dialysis is uncommon, the fact that some AKI patients will develop CKD still needs to be taken into consideration.