Diagnosis of osteoarthritis: imaging

High-Field MRI Advantages and Applications in Rheumatology

Imaging of rheumatologic diseases has historically been performed using conventional radiography. MRI offers an opportunity for detection of altered marrow signal in early disease that is not visible on other imaging modalities such as radiography, computed tomography, or sonography. This review describes the advantages of current MRI techniques in the diagnosis and treatment monitoring of rheumatologic diseases. In addition, this review discusses novel MRI techniques at high-field magnetic strength which may be deployed in the future to allow for improved imaging resolution and quantitative assessment of both axial and peripheral joints.

Influence of Health Insurance Coverage on the Survival Rate for Primary Total Knee Arthroplasty: Minimum 5-Year Follow-Up Analysis

This study investigated whether differences in survival rates and clinical outcomes exist in patients undergoing TKA by insurance type: National Health Insurance (NHI) vs. Medical Aid Program (MAP). This study conducted a retrospective analysis of 762 TKAs (NHI, n = 505; MAP, n = 257) with a mean follow-up of 8.4 ± 1.8 years. Patient-reported outcomes (PROMs) were evaluated using the American Knee Society's (AKS) score at the final follow-up. The survival rate of each group was analyzed using Kaplan-Meier survival analysis. Any postoperative complications and readmissions within 90 days of discharge were recorded and compared between the groups. There were no between-group differences in pre- to postoperative improvement in AKS scores. The estimated 10-year survival rates were 98.5% in the NHI group and 96.9% in the MAP group, respectively, with no significant differences (p = 0.48). However, the length of hospital stay (LOS) was significantly longer in the MAP group than in the NHI group (13.4 days vs. 13.1 days, p = 0.03), and the transfer rate to other departments was significantly higher in the MAP group than in the NHI group (3.9% vs. 1.4%, p = 0.04). Readmission rates for orthopedic complications for 90 days were 3.0% in the NHI group and 3.5% in the MAP group, respectively (p = 0.67). Patients' insurance type showed similar survival rates and clinical outcomes to those of primary TKA at a mean follow-up of 8.4 years, but the LOS and rate of transfer to other departments during hospitalization were influenced by insurance type.

Effectiveness of extracorporeal shock wave therapy on functional ability in grade IV knee osteoarthritis - a randomized controlled trial

Extracorporeal shockwave therapy (ESWT) is a non-invasive physical therapy intervention that has emerged in the recent past to address the upswing of osteoarthritis (OA). However, insufficient evidence is present to prove the efficacy of ESWT on grade IV knee osteoarthritis (KOA). The present study aimed to examine the effects of ESWT on functional ability in patients suffering from grade IV KOA. Thirty volunteers aged 45-60 years with grade IV primary KOA diagnosed by an orthopaedic surgeon based on the Kellgren-Lawrence score participated in the study. The participants were equally and randomly divided into two groups (i.e. experimental and control), with 15 participants in each group. The participants in the control group performed conventional physiotherapy (CPT) that included ultrasound therapy, isometric quadriceps, SLR and isometric hip adductor strengthening exercises. The participants in the experimental group received ESWT in addition to CPT. Lower extremity functional scale (LEFS) score was measured before and after the four weeks of intervention. In both groups, a statistically significant (p = 0.001) improvement in LEFS was observed. In the experimental groups, it improved by 81.92% and in the control groups by 48.15%. A statistically significant (p < 0.001) difference was observed in LEFS post-intervention values between both groups. As demonstrated by our trial results, the addition of ESWT to the CPT program will yield beneficial results in ameliorating the functional disability in patients with primary KOA (grade IV). Further studies are needed to confirm and apply these findings to a larger cohort.

Diagnostic value of ultrasonography in knee osteoarthritis: A systematic review

Background

Knee osteoarthritis (KOA) is the most expected diagnosis for an arthropathy that causes discomfort and disability in older adults. Radiography is frequently used to assess patients with KOA and there have been few prior research evaluating the diagnostic efficacy of ultrasonography (US). The current study sought to assess the diagnostic efficacy of the US in identifying various characteristics of KOA in the scientific literature.

Materials and Methods

This study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta Analyses statement. A systematic search in PubMed, Web of Science, Scopus, and Embase databases was completed in March 2023. This study focused on the diagnostic value of US in KOA, including sensitivity, specificity, positive predictive value, and negative predictive value. The quality assessment was conducted using the Joanna Briggs Institute critical appraisal tools.

Results

Out of 552 records of database searches, finally, two studies met this systematic review's eligibility criteria and were included in the study. Both of the included studies were cross sectional studies. US demonstrated remarkable sensitivity with adequate specificity for the detection of radiographic knee OA; however, it was found not to be an appropriate method for the detection of early KOA.

Conclusion

This study as the first systematic review aims to evaluate the diagnostic performance of US in detecting KOA. These findings shed light on the importance of investigating the different US features in the evaluation of KOA to reach appropriate sensitivity and specificity in the diagnosis.

Holistic vibrational spectromics assessment of human cartilage for osteoarthritis diagnosis

Osteoarthritis (OA) is the most common degenerative joint disease, presented as wearing down of articular cartilage and resulting in pain and limited mobility for 1 in 10 adults in the UK [Osteoarthr. Cartil.28(6), 792 (2020)10.1016/j.joca.2020.03.004]. There is an unmet need for patient friendly paradigms for clinical assessment that do not use ionizing radiation (CT), exogenous contrast enhancing dyes (MRI), and biopsy. Hence, techniques that use non-destructive, near- and shortwave infrared light (NIR, SWIR) may be ideal for providing label-free, deep tissue interrogation. This study demonstrates multimodal "spectromics", low-level abstraction data fusion of non-destructive NIR Raman scattering spectroscopy and NIR-SWIR absorption spectroscopy, providing an enhanced, interpretable "fingerprint" for diagnosis of OA in human cartilage. This is proposed as method level innovation applicable to both arthro- or endoscopic (minimally invasive) or potential exoscopic (non-invasive) optical approaches. Samples were excised from femoral heads post hip arthroplasty from OA patients (n = 13) and age-matched control (osteoporosis) patients (n = 14). Under multivariate statistical analysis and supervised machine learning, tissue was classified to high precision: 100% segregation of tissue classes (using 10 principal components), and a classification accuracy of 95% (control) and 80% (OA), using the combined vibrational data. There was a marked performance improvement (5 to 6-fold for multivariate analysis) using the spectromics fingerprint compared to results obtained from solely Raman or NIR-SWIR data. Furthermore, clinically relevant tissue components were identified through discriminatory spectral features - spectromics biomarkers - allowing interpretable feedback from the enhanced fingerprint. In summary, spectromics provides comprehensive information for early OA detection and disease stratification, imperative for effective intervention in treating the degenerative onset disease for an aging demographic. This novel and elegant approach for data fusion is compatible with various NIR-SWIR optical devices that will allow deep non-destructive penetration.

Topical Diclofenac Reduces Joint Synovitis in Hand Osteoarthritis: A Pilot Investigation Using Fluorescent Optical Imaging

Purpose

Synovitis, the inflammation of joint synovia, is a prominent feature of osteoarthritis (OA) manifested by enhanced synovial vascularity, endothelial leakage, and perivascular oedema. In this pilot study, we assessed the effect of topical diclofenac in hand OA (HOA) using the established semi-quantitative methods Magnetic Resonance Imaging (MRI) and Ultrasonography (US), and compared them with Fluorescent Optical Imaging (FOI), an emerging imaging modality.

Patients and Methods

Ten patients with symptomatic and diagnosed HOA used topical diclofenac for 14 days, with FOI, MRI, US, and subjective pain assessed at Baseline and after 7 (Day 8), and 14 (Day 15) days of treatment. Changes in synovitis were assessed for all 10 joints of the hand (via sum scores), and separately for the two joints most affected by synovitis. A new, fully quantitative approach for objective synovitis assessment based on the FOI images was also developed and applied.

Results

The semi-quantitative analysis of the sum scores showed a small decrease in synovitis throughout the treatment duration across the different imaging modalities. The effect of the treatment was more prominent on the two most affected joints, with a synovitis reduction vs Baseline of 21.1% and 34.2% on Day 8 and Day 15, respectively, in the FOI. The quantitative FOI pixel analysis further strengthened the evidence for this effect, with observed reduction of 17.8% and 42.4% for Days 8 and 15, respectively. A similar trend was observed for subjective pain perception, with a reduction of 7.2 and 13.3 mm on Days 8 and 15.

Conclusion

This pilot study evidenced the effect of topical diclofenac on reducing synovitis in hand OA in semi- and fully quantitative analyses, with the effect being stronger in the most affected joints. Further, supporting studies are needed to probe the accuracy of the quantitative pixel analysis of FOI images.

Time-efficient combined morphologic and quantitative joint MRI: an in situ study of standardized knee cartilage defects in human cadaveric specimens

BACKGROUND

Quantitative techniques such as T2 and T1ρ mapping allow evaluating the cartilage and meniscus. We evaluated multi-interleaved X-prepared turbo-spin echo with intuitive relaxometry (MIXTURE) sequences with turbo spin-echo (TSE) contrast and additional parameter maps versus reference TSE sequences in an in situ model of human cartilage defects.

METHODS

Standardized cartilage defects of 8, 5, and 3 mm in diameter were created in the lateral femora of ten human cadaveric knee specimens (81 ± 10 years old; nine males, one female). MIXTURE sequences providing proton density-weighted fat-saturated images and T2 maps or T1-weighted images and T1ρ maps as well as the corresponding two- and three-dimensional TSE reference sequences were acquired before and after defect creation (3-T scanner; knee coil). Defect delineability, bone texture, and cartilage relaxation times were quantified. Appropriate parametric or non-parametric tests were used.

RESULTS

Overall, defect delineability and texture features were not significantly different between the MIXTURE and reference sequences (p ≤ 0.47). After defect creation, relaxation times significantly increased in the central femur (T2pre = 51 ± 4 ms [mean ± standard deviation] versus T2post = 56 ± 4 ms; p = 0.002) and all regions combined (T1ρpre = 40 ± 4 ms versus T1ρpost = 43 ± 4 ms; p = 0.004).

CONCLUSIONS

MIXTURE permitted time-efficient simultaneous morphologic and quantitative joint assessment based on clinical image contrasts. While providing T2 or T1ρ maps in clinically feasible scan time, morphologic image features, i.e., cartilage defects and bone texture, were comparable between MIXTURE and reference sequences.

RELEVANCE STATEMENT

Equally time-efficient and versatile, the MIXTURE sequence platform combines morphologic imaging using familiar contrasts, excellent image correspondence versus corresponding reference sequences and quantitative mapping information, thereby increasing the diagnostic value beyond mere morphology.

KEY POINTS

• Combined morphologic and quantitative MIXTURE sequences are based on three-dimensional TSE contrasts. • MIXTURE sequences were studied in an in situ human cartilage defect model. • Morphologic image features, i.e., defect delineabilty and bone texture, were investigated. • Morphologic image features were similar between MIXTURE and reference sequences. • MIXTURE allowed time-efficient simultaneous morphologic and quantitative knee joint assessment.

Laser-irradiating infrared attenuated total reflection spectroscopy of articular cartilage: Potential and challenges for diagnosing osteoarthritis

Objective

A prototype infrared attenuated total reflection (IR-ATR) laser spectroscopic system designed for in vivo classification of human cartilage tissue according to its histological health status during arthroscopic surgery is presented. Prior to real-world in vivo applications, this so-called osteoarthritis (OA) scanner has been tested at in vitro conditions revealing the challenges associated with complex sample matrices and the accordingly obtained sparse spectral datasets.

Methods

In vitro studies on human knee cartilage samples at different contact pressures (i.e., 0.2-0.5 ​MPa) allowed recording cartilage degeneration characteristic IR signatures comparable to in vivo conditions with high temporal resolution. Afterwards, the cartilage samples were assessed based on the clinically acknowledged osteoarthritis cartilage histopathology assessment (OARSI) system and correlated with the obtained sparse IR data.

Results

Amide and carbohydrate signal behavior was observed to be almost identical between the obtained sparse IR data and previously measured FTIR data used for sparse partial least squares discriminant analysis (SPLSDA) to identify the spectral regions relevant to cartilage condition. Contact pressures between 0.3 and 0.4 ​MPa seem to provide the best sparse IR spectra for cylindrical (d ​= ​3 ​mm) probe tips.

Conclusion

Laser-irradiating IR-ATR spectroscopy is a promising analytical technique for future arthroscopic applications to differentiate healthy and osteoarthritic cartilage tissue. However, this study also revealed that the flexible connection between the laser-based analyzer and the arthroscopic ATR-probe via IR-transparent fiberoptic cables may affect the robustness of the obtained IR data and requires further improvements.

Should We Wait for Bone-on-Bone Arthritis? Equivalent Clinical Outcomes in Patients Requiring Advanced Imaging Prior to Primary Total Hip Arthroplasty

INTRODUCTION

Plain radiographs remain the standard for diagnosing osteoarthritis (OA). Total hip arthroplasty (THA) is generally offered only for advanced OA by plain radiographs. Advanced imaging is used as an adjunct to assess OA severity in cases of progressive symptoms with less advanced OA by plain radiographs. The objective of this study was to compare outcomes following THA in patients who have advanced OA visualized by plain radiographs to patients who have less severe OA visualized by plain radiographs.

METHODS

From February 2016 to February 2020, 93 patients who had Kellgren-Lawrence (KL) grade 0 to 2 OA and underwent THA were identified. The median age was 65 years, and 55% were women. They were matched 1:3 to patients who underwent THA for KL 4 OA based on age, sex, BMI, and Charlson Comorbidity Index. The primary outcome was achievement of the Hip Injury and Osteoarthritis Outcome Score, Joint Replacement (HOOS JR) minimum clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptom state (PASS) at 1 year postoperatively.

RESULTS

There was no difference between the KL 0 to 2 and KL 4 cohorts in the achievement of HOOS JR MCID (86 versus 85.6%, P = 0.922), SCB (81.7 versus 80.2%, P = 0.751), or PASS (89.2 versus 85.6%, P = 0.374). The KL 0 to 2 cohort had a similar improvement in their 2-year HOOS JR (42.5 versus 38.6, P = 0.019).

CONCLUSION

In this series, there was no difference in outcomes following primary THA between patients who have severe OA on plain radiographs (KL 4) compared to those who have less severe OA (KL 0 to 2). In the setting of severe symptoms and the absence of advanced OA on radiographs, advanced imaging can be used to guide treatment and select patients who could benefit from THA.

Two for One-Combined Morphologic and Quantitative Knee Joint MRI Using a Versatile Turbo Spin-Echo Platform

Quantitative MRI techniques such as T2 and T1ρ mapping are beneficial in evaluating knee joint pathologies; however, long acquisition times limit their clinical adoption. MIXTURE (Multi-Interleaved X-prepared Turbo Spin-Echo with IntUitive RElaxometry) provides a versatile turbo spin-echo (TSE) platform for simultaneous morphologic and quantitative joint imaging. Two MIXTURE sequences were designed along clinical requirements: "MIX1", combining proton density (PD)-weighted fat-saturated (FS) images and T2 mapping (acquisition time: 4:59 min), and "MIX2", combining T1-weighted images and T1ρ mapping (6:38 min). MIXTURE sequences and their reference 2D and 3D TSE counterparts were acquired from ten human cadaveric knee joints at 3.0 T. Contrast, contrast-to-noise ratios, and coefficients of variation were comparatively evaluated using parametric tests. Clinical radiologists (n = 3) assessed diagnostic quality as a function of sequence and anatomic structure using five-point Likert scales and ordinal regression, with a significance level of α = 0.01. MIX1 and MIX2 had at least equal diagnostic quality compared to reference sequences of the same image weighting. Contrast, contrast-to-noise ratios, and coefficients of variation were largely similar for the PD-weighted FS and T1-weighted images. In clinically feasible scan times, MIXTURE sequences yield morphologic, TSE-based images of diagnostic quality and quantitative parameter maps with additional insights on soft tissue composition and ultrastructure.

Pain Management Strategies in Osteoarthritis

Pain is the major symptom of osteoarthritis (OA) and is an important factor in strategies to manage this disease. However, the current standard of care does not provide satisfactory pain relief for many patients. The pathophysiology of OA is complex, and its presentation as a clinical syndrome is associated with the pathologies of multiple joint tissues. Treatment options are generally classified as pharmacologic, nonpharmacologic, surgical, and complementary and/or alternative, typically used in combination to achieve optimal results. The goals of treatment are the alleviation of symptoms and improvement in functional status. Several studies are exploring various directions for OA pain management, including tissue regeneration techniques, personalized medicine, and targeted drug therapies. The aim of the present narrative review is to extensively describe all the treatments available in the current practice, further describing the most important innovative therapies. Advancements in understanding the molecular and genetic aspects of osteoarthritis may lead to more effective and tailored treatment approaches in the future.

[Current MR imaging of cartilage in the context of knee osteoarthritis (part 1) : Principles and sequences]

Magnetic resonance imaging (MRI) is the clinical method of choice for cartilage imaging in the context of degenerative and nondegenerative joint diseases. The MRI-based definitions of osteoarthritis rely on the detection of osteophytes, cartilage pathologies, bone marrow edema and meniscal lesions but currently a scientific consensus is lacking. In the clinical routine proton density-weighted, fat-suppressed 2D turbo spin echo sequences with echo times of 30-40 ms are predominantly used, which are sufficiently sensitive and specific for the assessment of cartilage. The additionally acquired T1-weighted sequences are primarily used for evaluating other intra-articular and periarticular structures. Diagnostically relevant artifacts include magic angle and chemical shift artifacts, which can lead to artificial signal enhancement in cartilage or incorrect representations of the subchondral lamina and its thickness. Although scientifically validated, high-resolution 3D gradient echo sequences (for cartilage segmentation) and compositional MR sequences (for quantification of physical tissue parameters) are currently reserved for scientific research questions. The future integration of artificial intelligence techniques in areas such as image reconstruction (to reduce scan times while maintaining image quality), image analysis (for automated identification of cartilage defects), and image postprocessing (for automated segmentation of cartilage in terms of volume and thickness) will significantly improve the diagnostic workflow and advance the field further.

Retrospective study of synovial chondromatosis of the temporomandibular joint: clinical and histopathologic analysis and the early-stage imaging features

OBJECTIVE

Herein, we aimed to study the clinical, radiographical, and histopathologic features of synovial chondromatosis in the temporomandibular joint (SC in TMJ) and provide references for early diagnosis and treatment prognosis.

STUDY DESIGN

The medical records and imaging examinations of patients with SC in TMJ, diagnosed using postoperative histopathologic examination, were reviewed and analyzed. Among them, 18 cases who lacked calcified loose bodies on spiral computed tomography or cone beam computed tomography (SCT/CBCT) were selected for further study. Descriptive statistical methods were used to analyze the clinical characteristics of patients.

RESULTS

The study included 100 patients with SC in TMJ, who were predominantly female (male to female: 1:3), and were aged from 21 to 77 years (median, 47). Radiopaque calcified lesions on SCT/CBCT were missing in 18 cases, but cartilaginous nodules were observed during surgery. The cases lacking calcification had a relatively shorter disease course, suggesting they were in the early stages of SC.

CONCLUSION

In the early stage of SC, although calcified loose bodies cannot be detected on SCT/CBCT, attention should be paid to the widening of the posterior superior joint space and sclerosis or slight erosion of the joint fossa. Magnetic resonance imaging would be helpful to detect the early-stage SC in TMJ.

A rapid VEGF-gene-sequence photoluminescence detector for osteoarthritis

Osteoarthritis (OA) has become a serious problem to the human society for years due to its high economic burden, disability, pain, and severe impact on the patient's lifestyle. The importance of current clinical imaging modalities in the assessment of the onset and progression of OA is well recognized by clinicians, but these modalities can only detect OA in the II stage with significant structural deterioration and clinical symptoms. Blood vessel formation induced by vascular endothelial growth factor (VEGF) occurs in the early stage and throughout the entire course of OA, enables VEGF relating gene sequence to act as a biomarker in the field of early diagnosis and monitoring of the disease. Here in, a facile rapid detection of VEGF relating ssDNA sequence was developed, in which manganese-based zeolitic imidazolate framework nanoparticles (Mn-ZIF-NPs) were synthesized by a simple coprecipitation strategy, followed by the introduction and surficial absorption of probe ssDNAs and the CRISPR/Cas12a system components. Furthermore, fluorescence experiments demonstrated that the biosensor displayed a low detection limit of 2.49 nM, a good linear response to the target ssDNA ranging from 10 nM to 500 nM, and the ability of distinguishing single nucleotide polymorphism. This finding opens a new window for the feasible and rapid detection of ssDNA molecules for the early diagnose of OA.

A proposed modification to the Kellgren and Lawrence classification for knee osteoarthritis using a compartment-specific approach

Purpose

Since Kellgren and Lawrence (KL) originally classified knee osteoarthritis, several authors have reported varying levels of reliability and a lack of uniformity in the use of this classification system. We propose several modifications to the KL classification including the use of a compartment-specific approach that we hypothesize will lead to a better understanding of knee OA while maintaining an adequate interobserver and intraobserver reliability.

Methods

We propose the addition of the lateral and skyline-view radiographs to the standard anteroposterior (AP) and lateral projections in the evaluation. Also suggest a more precise definition of the evaluated parameters; the addition of the subchondral cancellous bone as parameter of evaluation; and the assessment of medial tibiofemoral compartment (MTFC), lateral tibiofemoral compartment (LTFC) and patellofemoral compartment (PFC) separately resulting in a compartment-specific KL staging score rather than a single overall KL score. Six evaluators (two knee surgeons, two radiologists and two knee fellows) used the modified KL classification to classify 230 randomly selected knees on two separate occasions. Reliabilities were assessed by calculating Krippendorff's ⍺ coefficients.

Results

Two hundred and ten knees were included for final evaluation and analyses (53% left knees; 65% females; mean age 56 years old). Average interobserver reliability was moderate for all compartments (0.51 for the MTFC; 0.51 for the LTFC; and 0.56 for the PFC). Average intraobserver reliability was substantial for all compartments (0.63 for the MTFC; 0.65 for the LTFC; and 0.7 for the PFC). Experienced evaluators showed a higher intraobserver reliability than less-experienced evaluators.

Conclusions

A modified compartment-specific KL classification enables a practical and detailed description of knee OA involvement and demonstrates acceptable interobserver and intraobserver reliability. Level of Evidence: Level III.

Recent advances in polymeric microparticle-based drug delivery systems for knee osteoarthritis treatment

Due to the poor bioavailability and high joint clearance of drugs, sustained delivery of therapeutic agents has proven difficult in the treatment of osteoarthritis (OA). Intra-articular (IA) drug delivery strategy is an attractive option for enhancing OA patients' prognosis, for which various polymer materials have been used as drug carriers due to their attractive delivery properties, to slow or even reverse the progress of OA by prolonging the duration of therapeutic agent residence in the joint. This article focuses on the recent developments in natural and synthetic polymer-based microsphere drug delivery systems for treating knee osteoarthritis. It evaluates the translational potential of some novel formulations for clinical application.

Improving Image Classification of Knee Radiographs: An Automated Image Labeling Approach

Large numbers of radiographic images are available in musculoskeletal radiology practices which could be used for training of deep learning models for diagnosis of knee abnormalities. However, those images do not typically contain readily available labels due to limitations of human annotations. The purpose of our study was to develop an automated labeling approach that improves the image classification model to distinguish normal knee images from those with abnormalities or prior arthroplasty. The automated labeler was trained on a small set of labeled data to automatically label a much larger set of unlabeled data, further improving the image classification performance for knee radiographic diagnosis. We used BioBERT and EfficientNet as the feature extraction backbone of the labeler and imaging model, respectively. We developed our approach using 7382 patients and validated it on a separate set of 637 patients. The final image classification model, trained using both manually labeled and pseudo-labeled data, had the higher weighted average AUC (WA-AUC 0.903) value and higher AUC values among all classes (normal AUC 0.894; abnormal AUC 0.896, arthroplasty AUC 0.990) compared to the baseline model (WA-AUC = 0.857; normal AUC 0.842; abnormal AUC 0.848, arthroplasty AUC 0.987), trained using only manually labeled data. Statistical tests show that the improvement is significant on normal (p value < 0.002), abnormal (p value < 0.001), and WA-AUC (p value = 0.001). Our findings demonstrated that the proposed automated labeling approach significantly improves the performance of image classification for radiographic knee diagnosis, allowing for facilitating patient care and curation of large knee datasets.

Identification of key genes and their correlation with immune infiltration in osteoarthritis using integrative bioinformatics approaches and machine-learning strategies

Osteoarthritis (OA) is a common degenerative joint disease and is closely associated with chronic, low-grade inflammation. Regulating ferroptosis by targeting ferroptosis-related genes may be a fast and effective way to delay the degeneration of OA. However, the molecular mechanisms and gene targets related to ferroptosis in OA are still unclear. Data of OA samples from 3 gene expression omnibus (GEO) datasets were combined to identify differentially expressed genes (DEGs). Ferroptosis-related genes (FRGs) retrieved by the Ferroptosis database were intersected with DEGs, and the intersected hub genes were used for functional enrichment analysis. The feature genes were obtained from the least absolute shrinkage and selection operator (LASSO) algorithm, support vector machine recursive feature elimination (SVM-RFE) algorithm, and random forest (RF) algorithm. Single sample gene set enrichment analysis (ssGSEA) was used to compare immune infiltration between OA patients and normal controls, and the correlation between feature genes and immune cells was analyzed. The expression levels of feature genes were confirmed by RT-PCR. In addition, to explore the applicability of these genes, we extended the bioinformatics analysis of these feature genes to cancer. Finally, 4 feature genes, GABARAPL1, TNFAIP3, ARNTL, and JUN, were confirmed in OA. Theirs expression level were validated by RT-PCR. ROC curves of the 4 genes exhibit excellent diagnostic efficiency for OA, suggesting that the 4 genes were associated with the pathogenesis of OA. Another GEO dataset validated this result. Further analysis revealed that the 4 feature genes were all closely related to the immune infiltration cells in OA. Additionally, results of prognosis analysis indicated that JUN might be a promising therapeutic target for cancer. GABARAPL1, TNFAIP3, ARNTL, and JUN may be predicted biomarkers for OA. The feature genes and association between feature genes and immune infiltration may provide potential biomarkers for OA prediction along with the better assessment of the disease.

MRI overestimates articular cartilage thickness and volume compared to synchrotron radiation phase-contrast imaging

Accurate evaluation of morphological changes in articular cartilage are necessary for early detection of osteoarthritis (OA). 3T magnetic resonance imaging (MRI) has highly sensitive contrast resolution and is widely used clinically to detect OA. However, synchrotron radiation phase-contrast imaging computed tomography (SR-PCI) can also provide contrast to tissue interfaces that do not have sufficient absorption differences, with the added benefit of very high spatial resolution. Here, MRI was compared with SR-PCI for quantitative evaluation of human articular cartilage. Medial tibial condyles were harvested from non-OA donors and from OA patients receiving knee replacement surgery. Both imaging methods revealed that average cartilage thickness and cartilage volume were significantly reduced in the OA group, compared to the non-OA group. When comparing modalities, the superior resolution of SR-PCI enabled more precise mapping of the cartilage surface relative to MRI. As a result, MRI showed significantly higher average cartilage thickness and cartilage volume, compared to SR-PCI. These data highlight the potential for high-resolution imaging of articular cartilage using SR-PCI as a solution for early OA diagnosis. Recognizing current limitations of using a synchrotron for clinical imaging, we discuss its nascent utility for preclinical models, particularly longitudinal studies of live animal models of OA.

Clinical Outcome of Minimally Manipulated, Mechanically Isolated Autologous Adipose Tissue-Derived Stromal Vascular Fraction (Sahaj Therapy®) in Knee Osteoarthritis-Randomized Controlled Trial

Introduction

Regenerative therapy has shown promising results in the treatment of osteoarthritis (OA) knee with Kellgren-Lawrence (KL) Grades I-III. We compared the safety, efficacy, functional, and clinical outcomes of intra-articular implantation of autologous adipose tissue-derived stromal vascular fraction (SVF) isolated using direct ultrasonic cavitation (Sahaj therapy-Cell Innovation Patented Technology) and saline injection in knee osteoarthritis.

Materials and Methods

The present prospective observational study was conducted over 3 years. We enrolled 120 patients in our study, where four patients got excluded as they did not meet the inclusion criteria. The remaining 116 patients were randomized into two groups, one with autologous adipose tissue-derived SVF and the other group with saline injection. A comparison of mean KOOS and VAS scores at different follow-ups was done using Paired 't' test. A p value of < 0.05 was considered significant.

Results

The results show that the SVF group had significantly higher KOOS scores (78.49 ± 6.54 in the SVF group vs 59.19 ± 5.14 in the saline group), respectively (p < 0.001). Similarly, the SVF group had significantly lesser VAS scores (3.17 ± 0.94 in the SVF group vs 3.89 ± 1.04 in the saline group), respectively (p < 0.001).

Conclusions

Autologous adipose tissue-derived SVF is a better choice for treating knee osteoarthritis. For individuals with degenerative osteoarthritis, autologous SVF grafting in the same surgical procedure is an innovative and promising treatment modality. Even after 3 years of follow-up, the study participants with OA knee have shown a good clinical and functional outcome.

Charcot Neuroarthropathy of the Foot and Ankle in the Acute Setting: An Illustrative Case Report and Targeted Review

Charcot neuroarthropathy (CN) is a rare but serious sequela of diabetes and other diseases that cause peripheral neuropathy. It is most commonly characterized by degeneration of the foot and/or ankle joints leading to progressive deformity and altered weight-bearing. If left untreated, the deformities of CN lead to ulceration, infection, amputation, and even death. Because of the associated peripheral neuropathy and proprioception deficits that accompany CN, patients typically do not perceive the onset of joint destruction. Moreover, in the hands of the untrained clinician, the initial presentation of CN can easily be mistaken for infection, osteoarthritis, gout, or inflammatory arthropathy. Misdiagnosis can lead to the aforementioned serious sequelae of CN. Thus, an early accurate diagnosis and off-loading of the involved extremity, followed by prompt referral to a specialist trained in the care of CN are crucial to prevent the late-term sequelae of the disease. The purpose of this article was to create an opportunity for enhanced understanding between orthopedic surgeons and emergency physicians, to improve patient care through the optimization of diagnosis and early management of CN in the emergent setting.

A Novel Tool for Collaborative and Blinded Orthopedic Image Analysis

Image analysis plays a central role in orthopedics and research but comes with many challenges, including anonymization, bias, and achieving efficient analyses using multiple independent observers. Appropriate software is still lacking. Tyche is a free online tool that displays images in a random order without showing any metadata. Additionally, when using Tyche, observers can store results in the same window, and the final results are immediately visible to the project manager. In this study, we compared results from Tyche with those from a validated tool. One hundred pelvic radiographs were analyzed separately by five orthopedic surgeons using both Tyche and the validated software. Common orthopedic measurement modalities and scores were determined. The methods were compared using intra-class correlations and Fleiss' kappa coefficients as well as Bland-Altman plots. Significant correlations ranging from r = 0.17 (Kallgren and Lawrence Score) to r = 0.99 (area measurements) were calculated for inter- and intraobserver agreements between the two tools for all measurements. The Bland-Altman plots indicated the non-inferiority of either tool. The images were analyzed significantly faster when Tyche was used. We conclude that Tyche is a valid tool for use in orthopedic image analysis. Tyche could be utilized for determining inter- and intraobserver agreements, in multicenter studies and for score validations.

Platelet-Rich Plasma Power-Mix Gel (ppm)-An Orthobiologic Optimization Protocol Rich in Growth Factors and Fibrin

Platelet- and fibrin-rich orthobiologic products, such as autologous platelet concentrates, have been extensively studied and appreciated for their beneficial effects on multiple conditions. Platelet-rich plasma (PRP) and its derivatives, including platelet-rich fibrin (PRF), have demonstrated encouraging outcomes in clinical and laboratory settings, particularly in the treatment of musculoskeletal disorders such as osteoarthritis (OA). Although PRP and PRF have distinct characteristics, they share similar properties. The relative abundance of platelets, peripheral blood cells, and molecular components in these orthobiologic products stimulates numerous biological pathways. These include inflammatory modulation, augmented neovascularization, and the delivery of pro-anabolic stimuli that regulate cell recruitment, proliferation, and differentiation. Furthermore, the fibrinolytic system, which is sometimes overlooked, plays a crucial role in musculoskeletal regenerative medicine by regulating proteolytic activity and promoting the recruitment of inflammatory cells and mesenchymal stem cells (MSCs) in areas of tissue regeneration, such as bone, cartilage, and muscle. PRP acts as a potent signaling agent; however, it diffuses easily, while the fibrin from PRF offers a durable scaffolding effect that promotes cell activity. The combination of fibrin with hyaluronic acid (HA), another well-studied orthobiologic product, has been shown to improve its scaffolding properties, leading to more robust fibrin polymerization. This supports cell survival, attachment, migration, and proliferation. Therefore, the administration of the "power mix" containing HA and autologous PRP + PRF may prove to be a safe and cost-effective approach in regenerative medicine.

Proteoglycans in Articular Cartilage and Their Contribution to Chondral Injury and Repair Mechanisms

Proteoglycans are vital components of the extracellular matrix in articular cartilage, providing biomechanical properties crucial for its proper functioning. They are key players in chondral diseases, specifically in the degradation of the extracellular matrix. Evaluating proteoglycan molecules can serve as a biomarker for joint degradation in osteoarthritis patients, as well as assessing the quality of repaired tissue following different treatment strategies for chondral injuries. Despite ongoing research, understanding osteoarthritis and cartilage repair remains unclear, making the identification of key molecules essential for early diagnosis and effective treatment. This review offers an overview of proteoglycans as primary molecules in articular cartilage. It describes the various types of proteoglycans present in both healthy and damaged cartilage, highlighting their roles. Additionally, the review emphasizes the importance of assessing proteoglycans to evaluate the quality of repaired articular tissue. It concludes by providing a visual and narrative description of aggrecan distribution and presence in healthy cartilage. Proteoglycans, such as aggrecan, biglycan, decorin, perlecan, and versican, significantly contribute to maintaining the health of articular cartilage and the cartilage repair process. Therefore, studying these proteoglycans is vital for early diagnosis, evaluating the quality of repaired cartilage, and assessing treatment effectiveness.

Histological features of knee osteoarthritis treated with triamcinolone acetonide and hyaluronic acid

Osteoarthritis (OA) is one of the most common degenerative joint diseases leading to disability in the end stage. Although intra-articular triamcinolone acetonide (TA) is one of the OA treatments that have been widely used, the side effects of such corticosteroids are still controversial. Intra-articular hyaluronic acid (HA) injection is another therapeutic option for patients with OA who do not want to use corticosteroids because of their side effects. However, the difference between the histological features associated with TA and HA in the treatment of OA remains unclear. Thus, the present study aimed to compare the histological effects of TA and HA on the cartilage of patients with knee OA. In the current study, 31 patients diagnosed with grade 3-4 knee OA on the Kellgren-Lawrence radiographic grading scale were separated into three groups: TA (n=12); HA (n=7) and untreated group (n=12). Histological examination of the whole articular cartilages of the patients was performed with hematoxylin and eosin and Alcian staining, as well as using a TUNEL assay. Clinical data such as cartilage thickness, structural and component deterioration, proteoglycan levels, apoptosis and empty lacunae were compared between the three groups. The results showed a high level of deterioration in both TA and HA groups but not in the untreated group, although the thickness of cartilage in the HA group was lower compared with that in the TA and untreated groups. The proteoglycan levels in the TA group were lower compared with those in the HA group. Moreover, the number of empty lacunae in the HA group was higher compared with that in the TA group, while no difference in apoptosis was found between TA and HA groups. A significant difference was not found in the histological staining between TA and HA groups. On the other hand, a significant difference was found in cartilage deterioration between the medial and lateral sides in these groups. TA and HA groups showed comparable histological results. TA injection is cheaper and easier but has more adverse effects for patients with knee OA than HA injection. Therefore, orthopaedists should select TA or HA based on the economic and specific needs of patients.

The role of imaging in osteoarthritis

Osteoarthritis is a complex whole-organ disorder that involves molecular, anatomic, and physiologic derangement. Advances in imaging techniques have expanded the role of imaging in evaluating osteoarthritis and functional changes. Radiography, magnetic resonance imaging, computed tomography (CT), and ultrasonography are commonly used imaging modalities, each with advantages and limitations in evaluating osteoarthritis. Radiography comprehensively analyses alignment and osseous features, while MRI provides detailed information about cartilage damage, bone marrow edema, synovitis, and soft tissue abnormalities. Compositional imaging derives quantitative data for detecting cartilage and tendon degeneration before structural damage occurs. Ultrasonography permits real-time scanning and dynamic joint evaluation, whereas CT is useful for assessing final osseous detail. Imaging plays an essential role in the diagnosis, management, and research of osteoarthritis. The use of imaging can help differentiate osteoarthritis from other diseases with similar symptoms, and recent advances in deep learning have made the acquisition, management, and interpretation of imaging data more efficient and accurate. Imaging is useful in monitoring and predicting the prognosis of osteoarthritis, expanding our understanding of its pathophysiology. Ultimately, this enables early detection and personalized medicine for patients with osteoarthritis. This article reviews the current state of imaging in osteoarthritis, focusing on the strengths and limitations of various imaging modalities, and introduces advanced techniques, including deep learning, applied in clinical practice.

Clinical aspects and outcomes in osteoarthritis

Osteoarthritis (OA) is the most prevalent type of arthritis worldwide, and its incidence significantly increases with age. It commonly affects the knees, hips, spine, big toes, and hands. OA can be identified through clinical examination, symptoms, and imaging methods. Its main symptoms include pain, stiffness, and limitations in joint movement. Examinations may reveal coarse crepitus, bony enlargement, and tenderness at the joint line. In severe cases of OA, rest pain, night pain, and deformity may occur. OA can lead to decreased physical activity, function, and quality of life due to symptoms such as pain and stiffness. To evaluate these impacts, patient-reported outcome measures (PROMs) are necessary. Various generic, disease-specific, and joint-specific PROMs have been developed and used in clinical practice to assess the outcomes of OA.

Indications of musculoskeletal health in deceased male individuals with lower-limb amputations: comparison to non-amputee and diabetic controls

Individuals with lower-limb amputations, many of whom have type 2 diabetes, experience impaired musculoskeletal health. This study: (1) compared residual and intact limbs of diabetic and non-diabetic post-mortem individuals with amputation to identify structures vulnerable to injury, and (2) compared findings to diabetic and healthy control groups to differentiate influences of amputation and diabetes on musculoskeletal health. Postmortem CT scans of three groups, ten individuals each, were included: (1) individuals with transtibial or transfemoral amputations, half with diabetes (2) diabetic controls, and (3) healthy controls. Hip and knee joint spaces, cross-sectional thigh muscle and fat areas, and cross-sectional bone properties (e.g. area, thickness, geometry) were measured. Wilcoxon Signed-Rank and Kruskal-Wallis tests assessed statistical significance. Asymmetry percentages between limbs assessed clinical significance. Residual limbs of individuals with amputation, particularly those with diabetes, had significantly less thigh muscle area and thinner distal femoral cortical bone compared to intact limbs. Compared to control groups, individuals with amputation had significantly narrower joint spaces, less thigh muscle area bilaterally, and thinner proximal femoral cortical bone in the residual limb. Diabetic individuals with amputation had the most clinically significant asymmetry. Findings tended to align with those of living individuals. However, lack of available medical information and small sample sizes reduced the anticipated clinical utility. Larger sample sizes of living individuals are needed to assess generalizability of findings. Quantifying musculoskeletal properties and differentiating influences of amputation and diabetes could eventually help direct rehabilitation techniques.

Point-of-Care Testing of the MTF1 Osteoarthritis Biomarker Using Phenolphthalein-Soaked Swabs

Osteoarthritis (OA) is the most common joint disease, which accompanies pain and inconvenience in daily life owing to degradation of cartilage and adjacent tissues. In this study, we propose a simple point-of-care testing (POCT) kit for the detection of the MTF1 OA biomarker to achieve on-site clinical diagnosis of OA. The kit contains an FTA card for patient sample treatments, a sample tube for loop-mediated isothermal amplification (LAMP), and a phenolphthalein-soaked swab for naked eye detection. The MTF1 gene was isolated from synovial fluids using an FTA card and amplified using the LAMP method at 65 °C for 35 min. A test part of the phenolphthalein-soaked swab was decolorized in the presence of the MTF1 gene due to the pH change after the LAMP, but the color remained pink in the absence of the MTF1 gene. The control part of the swab served as a reference color in relation to the test part. When real-time LAMP (RT-LAMP), gel electrophoresis, and colorimetric detection of the MTF1 gene were performed, the limit of detection (LOD) was confirmed at 10 fg/μL, and the overall processes were completed in 1 h. The detection of an OA biomarker in the form of POCT was reported for the first time in this study. The introduced method is expected to serve as a POCT platform directly applicable by clinicians for easy and rapid identification of OA.

The prevalence of hip osteoarthritis: a systematic review and meta-analysis

OBJECTIVE

To estimate the global prevalence of hip osteoarthritis (HOA) through a systematic review and meta-analysis, and to determine by regression analysis the respective relationships between age and sex, and sex and prevalence.

METHODS

EMBASE, PubMed, Web of science, CINAHL, and SCOPUS were searched from inception until August 2022. Two authors independently extracted data and assessed the quality of the retrieved literature. Random-effects meta-analysis was performed to derive the pooled prevalence. Variations in the prevalence estimate in different subgroups, including diagnostic methods, region, and patient sex, were examined by subgroup meta-analysis. Meta-regression was used to construct the age-specific prevalence of HOA.

RESULTS

A total of 31 studies were included in our analysis, involving 326,463 participants. Quality evaluation showed that all studies included in the analysis had a Quality Score of at least 4. The most frequently used method for diagnosing HOA was the Kellgren-Lawrence (K-L) grade classification, accounting for 19/31 (61.3%) studies. The pooled prevalence of HOA diagnosed based on the K-L grade ≥ 2 criterion was 8.55% (95% CI 4.85-13.18) worldwide. The prevalence of HOA was lowest in Africa at 1.20% (95% CI: 0.40-2.38), followed by Asia at 4.26% (95% CI 0.02-14.93) and North America at 7.95% (95% CI 1.98-17.36), and highest in Europe at 12.59% (95% CI 7.17-19.25). There was no statistically significant difference in HOA prevalence between men (9.42%, 95% CI:4.81-15.34) and women at (7.94%, 95% CI: 3.57-13.81). The regression model showed a correlation between age and the prevalence of HOA.

CONCLUSION

HOA has high prevalence worldwide and increases with age. The prevalence varies significantly by region but not by patient sex. High-quality epidemiological studies are warranted to more accurately estimate the prevalence of HOA.

Construction of a Diagnostic m7G Regulator-Mediated Scoring Model for Identifying the Characteristics and Immune Landscapes of Osteoarthritis

With the increasingly serious burden of osteoarthritis (OA) on modern society, it is urgent to propose novel diagnostic biomarkers and differentiation models for OA. 7-methylguanosine (m7G), as one of the most common base modification forms in post transcriptional regulation, through which the seventh position N of guanine (G) of messenger RNA is modified by methyl under the action of methyltransferase; it has been found that it plays a crucial role in different diseases. Therefore, we explored the relationship between OA and m7G. Based on the expression level of 18 m7G-related regulators, we identified nine significant regulators. Then, via a series of methods of machine learning, such as support vector machine recursive feature elimination, random forest and lasso-cox regression analysis, a total of four significant regulators were further identified (DCP2, EIF4E2, LARP1 and SNUPN). Additionally, according to the expression level of the above four regulators, two different m7G-related clusters were divided via consensus cluster analysis. Furthermore, via immune infiltration, differential expression analysis and enrichment analysis, we explored the characteristic of the above two different clusters. An m7G-related scoring model was constructed via the PCA algorithm. Meanwhile, there was a different immune status and correlation for immune checkpoint inhibitors between the above two clusters. The expression difference of the above four regulators was verified via real-time quantitative polymerase chain reaction. Overall, a total of four biomarkers were identified and two different m7G-related subsets of OA with different immune microenvironment were obtained. Meanwhile, the construction of m7G-related Scoring model may provide some new strategies and insights for the therapy and diagnosis of OA patients.

Localized Multi-Site Knee Bioimpedance as a Predictor for Knee Osteoarthritis Associated Pain Within Older Adults During Free-Living

The drastic increase in the aging population has increased the prevalence of osteoarthritis in the United States. The ability to monitor symptoms of osteoarthritis (such as pain) within a free-living environment could improve understanding of each person's experiences with this disease and provide opportunities to personalize treatments specific to each person and their experience. In this work, localized knee tissue bioimpedance and self-reports of knee pain were collected from older adults ([Formula: see text]) with and without knee osteoarthritis over 7 days of free-living to evaluate if knee tissue bioimpedance is associated with persons' knee pain experience. Within the group of persons' with knee osteoarthritis increases in 128 kHz per-length resistance and decreases in 40 kHz per-length reactance were associated with increased probability of persons having active knee pain ([Formula: see text] and [Formula: see text]).

Getting Cartilage Thickness Measurements Right: A Systematic Inter-Method Comparison Using MRI Data from the Osteoarthritis Initiative

OBJECTIVE

Magnetic resonance imaging is the standard imaging modality to assess articular cartilage. As the imaging surrogate of degenerative joint disease, cartilage thickness is commonly quantified after tissue segmentation. In lack of a standard method, this study systematically compared five methods for automatic cartilage thickness measurements across the knee joint and as a function of region and sub-region: 3D mesh normals (3D-MN), 3D nearest neighbors (3D-NN), 3D ray tracing (3D-RT), 2D centerline normals (2D-CN), and 2D surface normals (2D-SN).

DESIGN

Based on the manually segmented femoral and tibial cartilage of 507 human knee joints, mean cartilage thickness was computed for the entire femorotibial joint, 4 joint regions, and 20 subregions using these methods. Inter-method comparisons of mean cartilage thickness and computation times were performed by one-way analysis of variance (ANOVA), Bland-Altman analyses and Lin's concordance correlation coefficient (CCC).

RESULTS

Mean inter-method differences in cartilage thickness were significant in nearly all subregions (P < 0.001). By trend, mean differences were smallest between 3D-MN and 2D-SN in most (sub)regions, which is also reflected by highest quantitative inter-method agreement and CCCs. 3D-RT was prone to severe overestimation of up to 2.5 mm. 3D-MN, 3D-NN, and 2D-SN required mean processing times of ≤5.3 s per joint and were thus similarly efficient, whereas the time demand of 2D-CN and 3D-RT was much larger at 133 ± 29 and 351 ± 10 s per joint (P < 0.001).

CONCLUSIONS

In automatic cartilage thickness determination, quantification accuracy and computational burden are largely affected by the underlying method. Mesh and surface normals or nearest neighbor searches should be used because they accurately capture variable geometries while being time-efficient.

ssDNA-Modified Gold Nanoparticles as a Tool to Detect miRNA Biomarkers in Osteoarthritis

Recently, miRNAs have been established as promising, specific biomarkers for the diagnosis of many diseases, including osteoarthritis. Herein, we report a ssDNA-based detection method for miRNAs implicated in osteoarthritis, specifically, miR-93 and miR-223. In this study, gold nanoparticles (AuNPs) were modified with oligonucleotide ssDNA to detect miRNAs circulating in the blood in healthy subjects and patients suffering from osteoarthritis. The detection method was based on the colorimetric and spectrophotometric assessment of biofunctionalized AuNPs upon interaction with the target and their subsequent aggregation. Results showed that these methods could be used to detect easily and rapidly miR-93 but not miR-223 in osteoarthritic patients, and they could potentially be used as a diagnostic tool for blood biomarkers. Visual-based detection as well as spectroscopic methods are simple, rapid, and label-free, due to which they can be used as a diagnostic tool.

Sustained release resolvin D1 liposomes are effective in the treatment of osteoarthritis in obese mice

Osteoarthritis (OA) is the most common joint disorder and currently affects >500 million patients worldwide, with ~60% of them also suffering from obesity. There is no drug approved for human use that changes the course of OA progression. OA is one of the most common comorbidities of obesity, and obesity-related OA (ObOA) is a serious health concern because it shows heightened severity of tissue damage and also predominantly affects the working population. Unresolved inflammation is a major driver of ObOA, thus, resolving disease-associated inflammation is a viable strategy to treat ObOA. Resolvins are highly potent molecules that play a role in the resolution of inflammation and promote tissue healing. However, small molecules (like Resolvin D1; RvD1) have to be administered frequently or prior to injury because they lose their in vivo activity rapidly either by lymphatic clearance, or oxidation-mediated deactivation. In this study, we have encapsulated RvD1 in liposomes and established its efficacy in the mouse model of ObOA at much lower dosages than freely administered RvD1. Liposomal RvD1 (lipo-RvD1) acted as a source of the RvD1 molecules for ~11 days in vitro in synovial fluid derived from patients. When administered prophylactically or therapeutically, lipo-RvD1 suppressed cartilage damage in male C57BL/6 mice compared to untreated and free RvD1 treatments. This efficacy was achieved by increasing the proportion of the proresolution M2 macrophages over proinflammatory M1 macrophages in the synovial membrane. These results show the potential of lipo-RvD1 as an anti-OA agent.

Surgical Versus Non-Surgical Treatments for the Knee: Which Is More Effective?

Osteoarthritis is a degenerative joint disease that is extremely prevalent in society. It affects more than 25% of Americans above the age of 18 years. According to July 2020 publication by the Centers for Disease Control (CDC), osteoarthritis affects approximately 325 million Americans. One of the organs that is most affected by osteoarthritis is the knee. Over the years, we have developed non-surgical treatments, such as physical therapy (PT) and injections, and surgical treatments, such as total knee arthroplasty (TKA) and arthroscopic lavage, for knee osteoarthritis (KOA). If a patient fails with non-surgical options, which are tried first to avoid the risks of surgery, the patient may be considered for knee surgery. This article will investigate the different non-surgical options and TKA as treatment options for KOA based on current literature. The goal of this paper is to be a comprehensive resource for physicians and patients with KOA to make an informed decision. A systematic literature search was conducted using PubMed. The search terms were based on the type of treatments for KOA. To find articles that compared TKA to non-surgical treatments, the terms included "osteoarthritis", "total knee", and "non-surgical treatments," in combination. For other non-surgical treatments such as PT, weight reduction, and injections, a combination of the treatment, "osteoarthritis", and "knee" were included in the search. For the tier 1 process, any randomized controlled trials were included. Any case reports, observational studies, and cross-sectional studies were eliminated from the search. For the tier 2 review process, any articles that did not have relevance to the topic were eliminated after reading the abstracts of the articles. After review of the literature, the data seem to suggest that TKA with 12 weeks of non-surgical treatment improved pain and functionality of the knee more than just 12 weeks of non-surgical treatment when followed up at 12 and 24 months. However, non-surgical treatment before TKA delays the need for surgery. Supervised PT, either in a group or individual format, has been shown to delay TKA in 95% patients in the group that received PT at the end of one year. In addition, weight reduction has been shown as an effective strategy to improve pain and functionality in KOA patients, which decreases the urgency for surgery. Furthermore, platelet-rich plasma (PRP) injections have been shown to have long-term symptomatic relief for KOA compared to hyaluronic acid (HA) and corticosteroid injections. However, HA and corticosteroid injections are beneficial in treating KOA more than receiving no treatment. Physicians often have difficulty deciding whether to pursue conservative or surgical treatment for patients with KOA. The non-surgical treatments explored in this review - PT, injections, and weight reduction - can provide symptomatic relief and, in some cases, delay the need for surgical intervention. However, based on some randomized clinical trials mentioned in the article, patients receiving TKA have more relief, better quality of life, and improved functionality compared to non-surgical therapy. However, a critical review of this important field of debate shows that there are limited randomized controlled studies comparing the effectiveness of TKA and non-surgical treatments for KOA. We believe that this controversial topic needs further clinical investigation.

Artificial-Intelligence-Aided Radiographic Diagnostic of Knee Osteoarthritis Leads to a Higher Association of Clinical Findings with Diagnostic Ratings

BACKGROUND

Radiographic knee osteoarthritis (OA) severity and clinical severity are often dissociated. Artificial intelligence (AI) aid was shown to increase inter-rater reliability in radiographic OA diagnosis. Thus, AI-aided radiographic diagnoses were compared against AI-unaided diagnoses with regard to their correlations with clinical severity.

METHODS

Seventy-one DICOMs (m/f = 27:42, mean age: 27.86 ± 6.5) (X-ray format) were used for AI analysis (KOALA software, IB Lab GmbH). Subjects were recruited from a physiotherapy trial (MLKOA). At baseline, each subject received (i) a knee X-ray and (ii) an assessment of five main scores (Tegner Scale (TAS); Knee Injury and Osteoarthritis Outcome Score (KOOS); International Physical Activity Questionnaire; Star Excursion Balance Test; Six-Minute Walk Test). Clinical assessments were repeated three times (weeks 6, 12 and 24). Three physicians analyzed the presented X-rays both with and without AI via KL grading. Analyses of the (i) inter-rater reliability (IRR) and (ii) Spearman's Correlation Test for the overall KL score for each individual rater with clinical score were performed.

RESULTS

We found that AI-aided diagnostic ratings had a higher association with the overall KL score and the KOOS. The amount of improvement due to AI depended on the individual rater.

CONCLUSION

AI-guided systems can improve the ratings of knee radiographs and show a stronger association with clinical severity. These results were shown to be influenced by individual readers. Thus, AI training amongst physicians might need to be increased. KL might be insufficient as a single tool for knee OA diagnosis.

Identification of the osteoarthritis signature gene PDK1 by machine learning and its regulatory mechanisms on chondrocyte autophagy and apoptosis

Background

Osteoarthritis (OA) is a degenerative joint disease frequently diagnosed in the elderly and middle-aged population. However, its specific pathogenesis has not been clarified. This study aimed to identify biomarkers for OA diagnosis and elucidate their potential mechanisms for restoring OA-dysregulated autophagy and inhibiting chondrocyte apoptosis in vitro.

Material and methods

Two publicly available transcriptomic mRNA OA-related datasets (GSE10575 and GSE51588) were explored for biomarker identification by least absolute shrinkage and selection operator (LASSO) regression, weighted gene co-expression network analysis (WGCNA), and support vector machine recursive feature elimination (SVM-RFE). We applied the GSE32317 and GSE55457 cohorts to validate the markers' efficacy for diagnosis. The connections of markers to chondrocyte autophagy and apoptosis in OA were also comprehensively explored in vitro using molecular biology approaches, including qRT-PCR and Western blot.

Results

We identified 286 differentially expressed genes (DEGs). These DEGs were enriched in the ECM-receptor interaction and PI3K/AKT signaling pathway. After external cohort validation and protein-protein interaction (PPI) network construction, PDK1 was finally identified as a diagnostic marker for OA. The pharmacological properties of BX795-downregulated PDK1 expression inhibited LPS-induced chondrocyte inflammation and apoptosis and rescued OA-dysregulated autophagy. Additionally, the phosphorylation of the mediators associated with the MAPK and PI3K/AKT pathways was significantly downregulated, indicating the regulatory function of PDK1 in apoptosis and autophagy via MAPK and PI3K/AKT-associated signaling pathways in chondrocytes. A significantly positive association between the PDK1 expression and Neutrophils, Eosinophils, Plasma cells, and activated CD4 memory T cells, as well as an evident negative correlation between T cells follicular helper and CD4 naive T cells, were detected in the immune cell infiltration analysis.

Conclusions

PDK1 can be used as a diagnostic marker for OA. Inhibition of its expression can rescue OA-dysregulated autophagy and inhibit apoptosis by reducing the phosphorylation of PI3K/AKT and MAPK signaling pathways.

Injectable Drug Delivery Systems for Osteoarthritis and Rheumatoid Arthritis

Joint diseases are one of the most common causes of morbidity and disability worldwide. The main diseases that affect joint cartilage are osteoarthritis and rheumatoid arthritis, which require chronic treatment focused on symptomatic relief. Conventional drugs administered through systemic or intra-articular routes have low accumulation and/or retention in articular cartilage, causing dose-limiting toxicities and reduced efficacy. Therefore, there is an urgent need to develop improved strategies for drug delivery, in particular, the use of micro- and nanotechnology-based methods. Encapsulation of therapeutic agents in delivery systems reduces drug efflux from the joint and protects against rapid cellular and enzymatic clearance following intra-articular injection. Consequently, the use of drug delivery systems decreases side effects and increases therapeutic efficacy due to enhanced drug retention in the intra-articular space. Additionally, the frequency of intra-articular administration is reduced, as delivery systems enable sustained drug release. This review summarizes various advanced drug delivery systems, such as nano- and microcarriers, developed for articular cartilage diseases.

Region of interest-specific loss functions improve T2 quantification with ultrafast T2 mapping MRI sequences in knee, hip and lumbar spine

MRI T2 mapping sequences quantitatively assess tissue health and depict early degenerative changes in musculoskeletal (MSK) tissues like cartilage and intervertebral discs (IVDs) but require long acquisition times. In MSK imaging, small features in cartilage and IVDs are crucial for diagnoses and must be preserved when reconstructing accelerated data. To these ends, we propose region of interest-specific postprocessing of accelerated acquisitions: a recurrent UNet deep learning architecture that provides T2 maps in knee cartilage, hip cartilage, and lumbar spine IVDs from accelerated T2-prepared snapshot gradient-echo acquisitions, optimizing for cartilage and IVD performance with a multi-component loss function that most heavily penalizes errors in those regions. Quantification errors in knee and hip cartilage were under 10% and 9% from acceleration factors R = 2 through 10, respectively, with bias for both under 3 ms for most of R = 2 through 12. In IVDs, mean quantification errors were under 12% from R = 2 through 6. A Gray Level Co-Occurrence Matrix-based scheme showed knee and hip pipelines outperformed state-of-the-art models, retaining smooth textures for most R and sharper ones through moderate R. Our methodology yields robust T2 maps while offering new approaches for optimizing and evaluating reconstruction algorithms to facilitate better preservation of small, clinically relevant features.

Impact of soft tissue around the knee on the efficacy of extracorporeal shockwave therapy in knee osteoarthritis

Knee osteoarthritis (KOA) is the leading cause of knee pain in middle-aged and older individuals. Extracorporeal shockwave therapy (ESWT) has been applied to treat patients with KOA to reduce pain and improve function. Patients (n = 123) diagnosed with KOA who received ESWT were selected to participate in this study, and were grouped according to their body mass index (BMI). The treatment parameters were as follows: 8000 pulses, 2.0 bar, 0.25 mJ/mm2, and 6 Hz/s once per week for 8 weeks. The visual analog scale (VAS), Lequesne index, and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) were measured to assess knee pain and functional recovery according to BMI groups. Radiographs were used to measure the richness of the soft tissue around the knee joint. The correlation between the distribution of tissue, pain, and functional improvement was analyzed using the receiver operator characteristic curve. All the patients showed a reduction in pain after treatment compared to that before treatment (P < .01). As measured by the VAS, the Lequesne and WOMAC indexes, after the intervention, the pain and functional index of the overweight and above BMI group improved to a greater extent than that of the normal or below normal BMI group (P < .01). The area under the curve showed, with VAS as the demarcation criterion, when the tibial plateau soft tissue ratio, femoral intercondylar apex soft tissue ratio, and medial tibial soft tissue ratio exceeded 1.538, 1.534, and 1.296, respectively, the patient's pain relief was more pronounced the ESWT treatment was better. With pain in WOMAC as the demarcation criterion, the tibial plateau soft tissue ratio, femoral intercondylar apex soft tissue ratio, and medial tibial soft tissue ratio also are positively correlated with pain relief in patients. When the Lequesne and WOMAC scores were the demarcation criteria, the patients' function improved significantly when the patella apical soft tissue ratio exceeded 2.401 and 2.635, respectively. ESWT can effectively alleviate pain and improve knee function in patients with KOA, and the soft tissue around the knee joint should also be an important reference factor in KOA treatment.

Upregulation of leucine-rich alpha-2 glycoprotein: A key regulator of inflammation and joint fibrosis in patients with severe knee osteoarthritis

Introduction

Osteoarthritis (OA) is a degenerative disease of the joints mainly affecting older individuals. Since the etiology behind the progression of OA is not well understood, several associated consequences, such as synovial joint stiffness and its progression due to joint fibrosis, are still poorly understood. Although a lot of developments have been achieved in the diagnosis and management of OA, synovial fibrosis remains one of the major challenging consequences. The present study was therefore focused on understanding the mechanism of synovial fibrosis, which may further contribute to improving symptomatic treatments, leading to overall improvements in the treatment outcomes of patients with OA.

Methods

We used advanced proteomic techniques including isobaric tag for relative and absolute quantitation and sequential window acquisition of all theoretical mass spectra for the identification of differentially expressed proteins in the plasma samples of patients with OA. An in silico study was carried out to evaluate the association of the identified proteins with their biological processes related to fibrosis and remodeling of the extracellular matrix (ECM). The most significantly upregulated protein was then validated by Western blot and enzyme-linked immunosorbent assay. The target protein was then further investigated for its role in inflammation and joint fibrosis using an in vitro study model.

Results

Leucine-rich alpha-2 glycoprotein (LRG1) was found to be the most highly differentially expressed upregulated (9.4-fold) protein in the plasma samples of patients with OA compared to healthy controls. The knockdown of LRG1 followed by in vitro studies revealed that this protein promotes the secretion of the ECM in synovial cells and actively plays a role in wound healing and cell migration. The knockdown of LRG1 further confirmed the reduction of the inflammatory- and fibrosis-related markers in primary cells.

Conclusion

LRG1 was identified as a highly significant upregulated protein in the plasma samples of patients with OA. It was found to be associated with increased fibrosis and cell migration, leading to enhanced inflammation and joint stiffness in OA pathogenesis.

Short- to Mid-Term Outcomes in Arthroscopic Debridement of the Knee: A Prospective Case Series

Introduction Osteoarthritis of the knee is a common debilitating disease in the elderly population. There are many treatment options available including physiotherapy, analgesics, steroid injections, arthroscopic debridement, high tibial osteotomy (HTO) and arthroplasty. Arthroscopic debridement is beneficial when patients are chosen with certain characteristics. This is a prospective case series where we have correlated the patient and disease characteristics, with the pre- and post-operative Oxford Knee Scores (OKS). Methods This study was done in a single centre with appropriate ethical committee approval and consent. Forty-nine patients were enrolled in the study. The scores were recorded pre-operatively and at 12 months after the interventions. Analysis was done for correlation of the outcome with patient characteristics, radiological and arthroscopic grading. Results Patients below the age of 56 years, with partial thickness chondral lesions, grade I-III Kellgren-Lawrence (KL) radiological grading and grade I-II Outerbridge arthroscopic grading showed significant improvement at 12 months. Conclusion Arthroscopic debridement is effective in younger patients with mild to moderate arthroscopic and radiologically graded osteoarthritis of the knee joint.

Associations Between Baseline and Longitudinal Semiautomated Quantitative Joint Space Width at the Hip and Incident Hip Osteoarthritis: Data From a Community-Based Cohort

OBJECTIVE

To evaluate quantitative joint space width (JSW) at 10-, 30-, and 50-degree locations in relation to incident radiographic and symptomatic hip osteoarthritis (HOA) in a community-based cohort.

METHODS

Data were from Johnston County OA Project participants with supine hip radiographs at each of 4 time points; all had Kellgren/Lawrence (K/L) grades and quantitative JSW. We assessed covariates (age, race, height, weight, body mass index [BMI]) associated with quantitative JSW and hip-level associations between quantitative JSW and HOA over time using sex-stratified and multivariable-adjusted linear mixed models. A cluster analysis with logistic regression estimated associations between quantitative JSW trajectory groups and incident radiographic HOA and symptomatic HOA.

RESULTS

At baseline, 397 participants (784 hips, 41% men, 24% Black, mean age 57 years) had a mean BMI of 29 kg/m2 . Over a mean of 18 years, 20% and 12% developed incident K/L grade-defined radiographic HOA or symptomatic HOA, respectively. Quantitative JSW was more sensitive to changes over time at 50 degrees. Values were stable among men but declined over time in women. Heavier women lost more quantitative JSW; changes in quantitative JSW were not significantly associated with race, education, or injury in women or men. In women only, loss of quantitative JSW over time was associated with 2-3 times higher odds of radiographic HOA and symptomatic HOA; among women and men, narrower baseline quantitative JSW was associated with these outcomes.

CONCLUSION

Hip quantitative JSW demonstrates marked differences in respect to sex, with significant loss over time only in women. Loss of quantitative JSW over time in women and narrower baseline quantitative JSW in men and women were associated with incident radiographic HOA and symptomatic HOA.

Radiological Evaluation of the Phenotype of Indian Osteoarthritic Knees based on the Coronal Plane Alignment of the Knee Classification (CPAK)

Background

Understanding constitutional alignment of the lower limb is essential to optimize alignment strategies during total knee arthroplasty. The coronal plane alignment of knee (CPAK) classification system was proposed as a comprehensive assessment tool based on coronal alignment and variations in joint line obliquity (JLO). This prospective observational cross-sectional study aimed to evaluate the phenotype of knees in the Indian population based on the CPAK system.

Methods

Two cohorts of individuals (250 young healthy volunteers and 250 elderly patients with knee osteoarthritis) underwent radiological assessment with long-leg radiographs and were classified based on the CPAK system. Measurements included the mechanical and arithmetic hip-knee-ankle angles (mHKA, aHKA), joint line obliquity (JLO), lateral distal femoral angle (mLDFA) and medial proximal tibial angle (mMPTA). Knees were grouped into 9 CPAK phenotypes based on aHKA and JLO.

Results

A total of 1000 knees were evaluated. In cohort-1 of healthy young adults, most knees were distributed in the CPAK class II phenotype (128 knees, 25.6%) followed by CPAK Type I (106 knees, 21.2%). In cohort-2 of elderly arthritic adults, most knees were distributed in Type I (294 knees, 58.8%) with constitutional varus and apex-distal joint line orientation.

Conclusion

The majority of the study population was found to have constitutional varus alignment. In addition, a high proportion of patients in both categories, especially arthritic patients undergoing TKA, were found to have varus alignment with an apex-distal oblique joint line. This classification may help optimize component positioning to restore constitutional alignment and joint line orientation during TKA.

Artificial intelligence, machine learning and deep learning in musculoskeletal imaging: Current applications

Artificial intelligence is rapidly expanding in all technological fields. The medical field, and especially diagnostic imaging, has been showing the highest developmental potential. Artificial intelligence aims at human intelligence simulation through the management of complex problems. This review describes the technical background of artificial intelligence, machine learning, and deep learning. The first section illustrates the general potential of artificial intelligence applications in the context of request management, data acquisition, image reconstruction, archiving, and communication systems. In the second section, the prospective of dedicated tools for segmentation, lesion detection, automatic diagnosis, and classification of musculoskeletal disorders is discussed.

Association between statins and progression of osteoarthritis features on magnetic resonance imaging in a predominantly pre-radiographic cohort: the Vancouver Longitudinal Study of Early Knee Osteoarthritis (VALSEKO): a cohort study

Background

To evaluate the effect of statin use on osteoarthritis (OA) incidence/progression using magnetic resonance imaging (MRI) in a population-based cohort with predominantly pre-radiographic knee OA.

Methods

A cohort aged 40–79 years with knee pain was recruited using random population sampling and followed for 7 years. Baseline exclusions were inflammatory arthritis, recent knee surgery/injury, and inability to undergo MRI. At baseline, current statin use was ascertained. Baseline and follow-up MRIs were read semi-quantitatively for cartilage damage (grade 0–4, 0/1 collapsed, 6 regions), osteophytes (grade 0–3, 8 regions), bone marrow lesions (BML) (grade 0–3, 6 regions) and effusion (grade 0–3). The primary outcome was cartilage damage incidence/progression, while secondary outcomes were incidence/progression of osteophytes, BML, and effusion, each defined as an increase by ≥1 grade at any region. To ensure population representative samples, sample weights were used. Logistic regression was used to assess the association of statin use at baseline with incidence/progression of MRI outcomes. Analyses were adjusted for sex, age, BMI, and multiple comorbidities requiring statin therapy.

Results

Of 255 participants evaluated at baseline, 122 completed the 7-year follow-up. Statin use was not significantly associated with progression of cartilage damage (OR 0.82; 95% CI 0.17, 4.06), osteophytes (OR 3.48; 95% CI 0.40, 30.31), BML (OR 0.61; 95% CI 0.12, 3.02), or effusion (OR 2.38; 95% CI 0.42, 13.63), after adjusting for confounders.

Conclusion

In this population-based cohort of predominantly pre-radiographic knee OA, statins did not affect MRI incidence/progression of cartilage damage, BML, osteophytes or effusion. Therefore, statin use does not appear to affect people with pre-radiographic stages of knee OA.