Intra-articular corticosteroids and the risk of knee osteoarthritis progression: results from the Osteoarthritis Initiative

Intra-articular corticosteroids for the treatment of osteoarthritis: A systematic review and meta-analysis on the comparison of different molecules and doses

Purpose

The purpose of this study was to quantify and compare the clinical relevance of the different intra-articular corticosteroids (CS) effects in vivo for osteoarthritis (OA) treatment.

Methods

The search was conducted on PubMed, Cochrane, and Web of Science in October 2023. The PRISMA guidelines were used. Inclusion criteria: animal or human randomized controlled trials (RCTs), English language and no time limitation, on the comparison of different intra-articular CS for OA treatment. The articles' quality was assessed using the Cochrane RoB2 and GRADE guidelines for human RCTs, and SYRCLE's tool for animal RCTs.

Results

Eighteen RCTs were selected (16 human and 2 animal studies), including 1577 patients (1837 joints) and 31 animals (51 joints). The CS used were triamcinolone (14 human and 2 animal studies), methylprednisolone (7 human and 1 animal study), betamethasone (3 human studies) and dexamethasone (1 human study). All studies addressed knee OA except for three human and one animal study. A meta-analysis was performed on the comparison of methylprednisolone and triamcinolone in humans with knee OA analysing VAS pain at very short- (≤2 weeks), short- (>2 and ≤4 weeks), mid- (>4 and ≤8 weeks), long- (>8 and ≤ 12 weeks), and very long-term (>12 and ≤24 weeks). Triamcinolone showed better post-injection values compared to methylprednisolone at very short-term (p = 0.028). No difference in terms of VAS improvement was observed at any follow-up.

Conclusions

The available preclinical and clinical literature provides limited evidence on the comparison of different CS, hindering the possibility of determining the best CS approach in terms of molecule and dose for the intra-articular injection of OA joints.

Level of Evidence

Level I.

Pharmacologic interventions for primary glenohumeral osteoarthritis

ABSTRACT

Primary glenohumeral osteoarthritis is a multifactorial condition with a complex cause that affects patients across different age groups, impairing physiologic and psychologic well-being, and substantially reducing patient quality of life and overall productivity. To effectively manage this condition, healthcare providers need to be well informed about treatment guidelines, as well as the available therapeutic options and the evidence supporting their use. Nonsurgical interventions should be regarded as the primary treatment option, particularly for patients in the initial phases of this condition. No conclusive guidelines exist for treating young and active patients, and the literature lacks high-quality data to evaluate the efficacy, safety, and long-term consequences of several interventions, regardless of patient characteristics and expectations.

The mediation effects of malalignment on the relation of sex to the risk of incidence tibiofemoral osteoarthritis

OBJECTIVE

To investigate to what extent the higher risk of tibiofemoral radiographic osteoarthritis (TFROA) in females vs. males can be explained by knee malalignment.

DESIGN

Using data from Multicenter Osteoarthritis Study (MOST) and Osteoarthritis Initiative (OAI), we examined the relation of sex to the incident medial and lateral TFROA and performed mediation analyses to assess to what extent varus and valgus malalignments account for sex differences in the incident medial or lateral TFROA.

RESULTS

Of the 3462 knees without medial and lateral TFROA in MOST, the 7-year risks of medial and lateral TFROA were 16.9% and 10.0% in females, and 15.8% and 4.2% in males, respectively. Females had 2.31-fold (95% confidence interval [95% CI]: 1.73 to 3.08) higher incident lateral TFROA than males, and the relative risk (RR) of the indirect effect of sex on lateral TFROA through valgus malalignment was 1.15 (95% CI: 1.09 to 1.20), accounting for 23% of its total effect on lateral TFROA. In OAI (n = 3095 knees), females had 1.54-fold (95% CI: 1.15 to 2.04) higher incident lateral TFROA than males, and RR of the indirect effect of sex on lateral TFROA through valgus malalignment was 1.10 (95% CI: 1.04 to 1.21), accounting for 26% of its total effect on lateral TFROA. No apparent sex difference in the incident medial TFROA was found in MOST (RR = 1.05, 95% CI: 0.89 to 1.25) or OAI (RR = 1.02, 95% CI: 0.84 to 1.19).

CONCLUSION

Females had a higher risk of developing lateral TFROA than males; however, valgus malalignment only modestly explained such a difference.

Viscosupplementation Is Effective for the Treatment of Osteoarthritis in the Hip: A Systematic Review

PURPOSE

To assess the efficacy of intra-articular viscosupplementation as a therapeutic intervention for hip osteoarthritis (OA), as well as to assess the duration of efficacy, effect of dose, composition and number of injections of the viscosupplement, and the incidence of adverse effects.

METHODS

We performed a systematic review using the literature search from the following databases: Embase, Medline, PubMed, Web of Science, and Scopus. Quality assessment of the included studies was performed using the Modified Newcastle-Ottawa Quality Assessment Scale. Random-effects meta-analysis and mixed-effects subgroup analysis were carried out, but due to the high heterogeneity, low level of evidence, and high risk of bias of the included studies after analyzing the data, weighted means and pooled estimates have not been provided. Instead, we have provided a subjective synthesis of the results.

RESULTS

Forty studies were included in the analysis from an initial search of 3,265 studies, with data from a total of 3,350 patients. The level of available evidence was low with an overall high risk of bias. Nearly all studies showed a reduction in mean pain at 1 month, 3 months, and 6 months of follow-up, as well as at the end point, and an improvement in mean patient-reported function was also seen at these time points. However, heterogeneity was extremely high at all time points and remained despite attempts at removing outliers. Subgroup analyses looking at the effects of dose, volume, composition of viscosupplement, and number of injections were carried out, but substantial heterogeneity still remained. There were no lasting adverse effects.

CONCLUSIONS

Weak evidence suggests that viscosupplementation improves patient-reported pain and function at end point compared to baseline, regardless of dose, volume, composition, and number of injections. However, due to the high heterogeneity, low level of evidence, and high risk of bias in the current available literature, the strength of our conclusions is limited.

LEVEL OF EVIDENCE

Level IV, systematic review of level I to IV studies.

Corticosteroid injections for the treatment of osteoarthritis present a wide spectrum of effects ranging from detrimental to disease-modifying: A systematic review of preclinical evidence by the ESSKA Orthobiologic Initiative

PURPOSE

Aim of this systematic review of preclinical evidence was to determine the effects of intra-articular corticosteroid (CS) injections in joints affected by osteoarthritis (OA).

METHODS

A systematic review was performed on animal studies evaluating intra-articular CS injections for OA joints. The search was performed on PubMed, Cochrane, and Web of Science databases. A synthesis of the results was performed investigating CS effects by evaluating studies comparing CS with control groups. Morphological, histological, immunohistochemistry evaluations, clinical outcomes, biomarkers and imaging results were evaluated. The risk of bias was assessed according to the Systematic Review Centre for Laboratory Animal Experimentation's tool.

RESULTS

Thirty-two articles analysing CS effects in OA animal models were included (1079 joints), 18 studies on small and 14 on large animals. CS injections showed overall positive effects in at least one of the outcomes in 68% of the studies, while 16% reported a deleterious effect. CS improved cartilage and synovial outcomes in 68% and 60% of the studies, but detrimental effects were documented in 11% and 20% of the studies, respectively. Clinical parameters evaluated in terms of pain, lameness or joint swelling improved in 63% of the studies but deteriorated in 13%. Evidence is limited on imaging and biomarkers results, as well as on the best CS type, dose, formulation and injection protocol. The risk of bias assessment revealed a 28% low and an 18% high risk of bias.

CONCLUSION

Intra-articular CS injections induced a wide range of results on OA joints in experimental animal models, from disease-modifying and positive effects on pain and joint function at short-term evaluation to the lack of benefit or even negative effects. This underlines the need to identify more specific indications and treatment modalities to avoid possible detrimental effects while maximising the anti-inflammatory properties and the benefits of intra-articular CS in OA joints.

LEVEL OF EVIDENCE

Level II.

Single dose thermoresponsive dexamethasone prodrug completely mitigates joint pain for 15 weeks in a murine model of osteoarthritis

In this study, we aimed to assess the analgesic efficacy of a thermoresponsive polymeric dexamethasone (Dex) prodrug (ProGel-Dex) in a mouse model of osteoarthritis (OA). At 12 weeks post model establishment, the OA mice received a single intra-articular (IA) injection of ProGel-Dex, dose-equivalent Dex, or Saline. Comparing to Saline and Dex controls, ProGel-Dex provided complete and sustained pain relief for >15 weeks according to incapacitance tests. In vivo optical imaging confirmed the continuous presence of ProGel-Dex in joints for 15 weeks post-injection. According to micro-CT analysis, ProGel-Dex treated mice had significantly lower subchondral bone thickness and medial meniscus bone volume than Dex and Saline controls. Except for a transient delay of body weight increase and slightly lower endpoint liver and spleen weights, no other adverse effect was observed after ProGel-Dex treatment. These findings support ProGel-Dex's potential as a potent and safe analgesic candidate for management of OA pain.

Contralateral knee osteoarthritis is a risk factor for ipsilateral knee osteoarthritis progressing: a case control study

BACKGROUND

Knee osteoarthritis (KOA) is a highly disabling disease, and studying its progression is crucial. However, it is still unclear whether the progression of ipsilateral knee osteoarthritis is influenced by contralateral knee osteoarthritis.

METHODS

Data were collected from the OAI database and divided into two study cohorts (right/left KOA cohort). Each cohort had a target knee (right/left knee) and was further divided into two groups (exposure/control group). The demographic data of both cohorts were balanced at baseline by propensity score matching (PSM), and the data included rating scale and radiographic and clinical data. After checking for balance in the matched variables, we then compared the differences between the two groups in each cohort. Our primary focus was on the minimum joint space width (mJSW) of the target knee, which was measured four years after baseline. The secondary outcome was the arthroplasty rate of the target knee within nine years.

RESULTS

In this study, a total of 678 participants were enrolled and matched. After 1:1 PSM of the baseline demographic data, 98 participants in the right KOA cohort (RKOAC) were successfully matched, and 117 participants in the left KOA cohort (LKOAC) were successfully matched. Furthermore, the standardized mean difference (SMD) of the matched variables in both cohorts was less than 0.25. After analyzing the outcome metrics, we found that the target knee had a significantly lower mJSW in the fourth year after baseline and a significantly greater arthroplasty rate within nine years in the exposed group than in the control group. RKOAC: mJSW (exposure: 2.6(1.1 ~ 3.6) vs. control: 3.3(2.0 ~ 4.2), P < 0.05), arthroplasty rate (exposure: 14(14.3%) vs. control: 4(4.1%), P < 0.05); LKOAC: mJSW (exposure: 3.1(2 ~ 3.9) vs. control: 3.4(2.6 ~ 4.2), P < 0.05), arthroplasty rate (exposure: 16(13.7%) vs. control: 7(6%), P < 0.05).

CONCLUSIONS

Patients with knee osteoarthritis experienced greater progression of osteoarthritis when the contralateral knee was also affected.

Local and Systemic Side Effects of Corticosteroid Injections for Musculoskeletal Indications

Corticosteroid injections can be associated with a range of potential side effects, which may be classified as local or systemic and further stratified as immediate or delayed in onset. Radiologists performing image-guided musculoskeletal injections should recognize the potential side effects of corticosteroid medication when counseling patients before injection and consider such side effects in planning individual injections. This Review summarizes the available evidence regarding the local and systemic side effects of corticosteroid injections performed for musculoskeletal indications. Local side effects include postinjection flare, skin hypopigmentation and atrophy, infection, tendon rupture, accelerated progression of osteoarthritis, and osseous injury. Systemic side effects include adrenal suppression or insufficiency, facial flushing, hypertension, hyperglycemia, and osteoporosis. Additional targeted counseling is warranted regarding side effects that are specific to certain patient populations (i.e., premenopausal women, patients with diabetes, athletes, and pediatric patients). Corticosteroid injections are contraindicated in the presence of superficial or deep infection, fracture, or a prosthetic joint. Guidelines on the frequency, duration, and maximal lifetime use of corticosteroid injections are currently lacking. Further research is needed regarding the long-term complications of continuous corticosteroid use, particularly with regard to osseous effects.

Nonsteroidal Anti-Inflammatory Drug Injections versus Steroid Injections in the Management of Upper and Lower Extremity Orthopedic Conditions: A Systematic Review with Meta-Analysis

BACKGROUND

Although corticosteroid injections are an effective treatment for musculoskeletal pathologies, they may not be suitable for all patients. The purpose of this systematic review was to compare clinical outcomes between patients who received NSAID and corticosteroid injections for various orthopedic conditions.

METHODS

Medline, Embase, Web of Science, and Cochrane Central Register of Controlled Trials were searched, and meta-analyses were performed using a random-effects model for outcomes presented in three or more studies. Other studies were qualitatively analyzed.

RESULTS

A total of 28 articles with 2113 patients were included. A meta-analysis of five studies in patients with shoulder impingement syndrome demonstrated that there was no significant difference in the pain visual analogue scale (VAS) between subacromial NSAID injections and corticosteroid injections at 1 month [weighted mean difference (WMD) -0.244; 95% CI, -1.232 to 0.745; I2, 94.5%]. For patients with knee osteoarthritis, a meta-analysis of three studies demonstrated that there was no significant difference between intraarticular NSAID injections and corticosteroid injections in pain VAS at 1 month (WMD 0.754; 95% CI, -0.413 to 1.921; I2, 90.2%) and 3 months (WMD-0.089; 95% CI, -0.345 to 0.166; I2, 0%). A review of the studies assessing pain outcomes for hip osteoarthritis, adhesive capsulitis, and plantar fasciitis showed no significant differences between the NSAID and corticosteroid groups.

CONCLUSION

NSAID injections may be safe and effective alternatives to steroid injections, especially in shoulder impingement syndrome and knee osteoarthritis.

Complications and opioid-prescribing patterns following genicular nerve radiofrequency ablation versus intra-articular injection: a matched cohort study

BACKGROUND AND OBJECTIVES

Genicular nerve radiofrequency ablation (GNRFA) is an emerging procedure used to relieve pain from severe knee osteoarthritis. While there have been rare reports of significant complications, their incidence has not been well established. The objective of this study was to examine complication rates at 30 and 90 days post treatment as well as characterize opioid-prescribing patterns before and after treatment.

METHODS

A large national database was queried to identify patients undergoing GNRFA from 2015 to 2022 and matched to control cohorts composed of patients receiving either intra-articular corticosteroid (CSI) or hyaluronic acid injection (HAI) of the knee. Complication rates at 30 and 90 days were analyzed. Opioid utilization was assessed in the 6 months before and after treatment.

RESULTS

Rates of infection (0.1%, CI 0.02% to 0.5% vs 0.2%, CI 0.05% to 0.6%), septic arthritis (<0.1%, CI 0.003% to 0.4% vs 0.1%, CI 0.02% to 0.5%), deep vein thrombosis (2.0%, CI 1.3% to 2.7% vs 1.6%, CI 1.0% to 2.2%), pulmonary embolism (1.2%, CI 0.6% to 1.7% vs 1.3%, CI 1.1% to 2.5%), bleeding (<0.1%, CI 0.003% to 0.4% vs 0%, CI 0% to 0.3%), seroma (<0.1%, CI 0.003% to 0.4% vs 0.2%, CI 0.05% to 0.6%), nerve injury (0%, CI 0% to 0.3% vs 0%, CI 0% to 0.3%) and thermal injury (0%, CI 0% to 0.3% vs 0%, CI 0% to 0.3%) were not different between CSI and GNRFA cohorts at 30 days. Rate of swelling was significantly greater in the GNRFA cohort (9.4%, CI 7.6% to 10.4% vs 6.4%, CI 4.8% to 7.2%, p=0.003) at 30 days. At 90 days, rates of septic arthritis (0.1%, CI 0.02% to 0.5% vs 0.3%, CI 0.08% to 0.7%), deep vein thrombosis (3.1%, CI 2.1% to 3.8% vs 3.1%, CI 2.2% to 3.9%), pulmonary embolism (1.5%, CI 0.9% to 2.1% vs 1.8%, CI 1.2% to 2.5%), and nerve injury (0%, CI 0% to 0.3% vs <0.1%, CI 0.003% to 0.4%) were not significantly different.Between HAI versus GNRFA cohorts, no significant differences were seen in rates of infection (0.3%, CI 0.08% to 0.07% vs 0.7%, CI 0.3% to 1.2%), septic arthritis (0.2%, CI 0.05% to 0.6% vs 0.4%, CI 0.2% to 0.9%), deep vein thrombosis (2.0%, CI 1.3% to 2.7% vs 1.9%, CI 1.2% to 2.7%), pulmonary embolism (1.5%, CI 0.9% to 2.2% vs 1.7%, CI 1.1% to 2.5%), bleeding (0.1%, CI 0.02% to 0.5% vs 0.2%, CI 0.05% to 0.6%), seroma (<0.1%, CI 0.03% to 0.4% vs 0%, CI 0% to 0.3%), nerve injury (0%, CI 0% to 0.3% vs 0%, CI 0% to 0.3%), swelling (14.0%, CI 11.6% to 15.1% vs 12.0%, CI 10.3% to 13.6%), and thermal injury (<0.1%, CI 0.03% to 0.4% vs <0.01%, CI 0.3% to 0.4%) at 30 days. Rates of infection (0.7%, CI 0.3% to 1.2% vs 1.4%, CI 0.9% to 2.1%), septic arthritis (0.3%, CI 0.1% to 0.8% vs 0.5%, CI 0.2% to 1.1%), deep vein thrombosis (3.6%, CI 2.6% to 4.4% vs 3.1%, CI 2.2% to 4.0%), pulmonary embolism (2.3%, CI 1.5% to 3.0% vs 2.1%, CI 1.4% to 3.0%) and nerve injury (0%, CI 0% to 0.3% vs 0.1%, CI 0.02% to 0.5%) were not significantly different at 90 days.There were no significant differences in level of pretreatment opioid utilization although overall consumption in mean daily morphine equivalents was greater in the GNRFA cohort. Opioid utilization significantly increased in the first 30 days after ablation in patients with no prior opioid use compared to controls. In patients with some and chronic prior opioid use, opioid requirements were generally decreased in all treatment groups at 6 months with no clearly superior treatment in reducing opioid consumption.

CONCLUSION

Our study demonstrated that GNRFA possesses a safety profile similar to that of intra-articular injections although significant adverse events such as venous thromboembolism and septic arthritis may occur rarely. Although opioid utilization generally increased in the 30 days after ablation compared with intra-articular injection, similar reduction in opioid consumption at 6 months was seen in patients with prior opioid use in the ablation and control cohorts.

Intra-articular corticosteroid injections provide a clinically relevant benefit compared to placebo only at short-term follow-up in patients with knee osteoarthritis: A systematic review and meta-analysis

PURPOSE

To quantify the clinical relevance of intra-articular corticosteroid effects compared to placebo for the injective treatment of knee osteoarthritis (OA).

METHODS

The PubMed, Cochrane Library and Web of Science databases were searched on May 3, 2023. This study was conducted in accordance with the PRISMA guidelines. The inclusion criteria were randomized controlled trials (RCTs), published in English, with no time limitation regarding publication date, comparing intra-articular corticosteroids and placebo injections for knee OA. The effects were quantified at short- (≤6 weeks), mid- (>6 weeks and ≤3 months), and long-term (≥6 months) follow-ups. The minimal clinically important difference (MCID) for the outcomes (visual analogue scale for pain - VAS: 1.4, Western Ontario and McMaster University Osteoarthritis Index - WOMAC: 9) was used to interpret the clinical improvement provided by intra-articular corticosteroid injections compared to placebo. The quality of each article was assessed using the Cochrane RoB 2 tool and the GRADE guidelines.

RESULTS

Among the 1030 articles retrieved, 11 RCTs (842 patients) were included. A comparison of the two groups revealed statistically significant differences in the improvement of VAS and WOMAC scores in terms of the mean difference (MD); this difference was in favour of corticosteroids at short-term (p < 0.001, MD = -1.6 and p < 0.001, MD = -9.9, respectively) and mid-term follow-ups (p = 0.001, mean MD = -1.3 and p = 0.005, MD = -4.9, respectively). No difference was observed at the long-term follow-up. The MDs between the improvements in the two groups reached the MCID values for the VAS and WOMAC only at the short-term follow-up. The RoB 2 tool and the GRADE evaluations showed the presence of risk of bias and limited quality of evidence.

CONCLUSION

This systematic review and meta-analysis demonstrated that intra-articular corticosteroid injections offer clinically perceivable pain relief and functional improvement higher than the placebo effect only at short-term follow-up in patients affected by knee OA, with benefits losing clinical relevance already after 6 weeks. These results, together with the low number and the limited quality of the RCTs comparing this treatment with placebo, question the indication for the use of corticosteroid injections in clinical practice for the treatment of knee OA.

LEVEL OF EVIDENCE

Level I.

Supramolecular self-assembly of EGCG-selenomethionine nanodrug for treating osteoarthritis

Osteoarthritis (OA) has emerged as a significant health concern among the elderly population, with increasing attention paid to ferroptosis-induced OA in recent years. However, the prolonged use of nonsteroidal anti-inflammatory drugs or corticosteroids can lead to a series of side effects and limited therapeutic efficacy. This study aimed to employ the Mannich condensation reaction between epigallocatechin-3-gallate (EGCG) and selenomethionine (SeMet) to efficiently synthesize polyphenol-based nanodrugs in aqueous media for treating OA. Molecular biology experiments demonstrated that EGCG-based nanodrugs (ES NDs) could effectively reduce glutathione peroxidase 4 (GPX4) inactivation, abnormal Fe2+ accumulation, and lipid peroxidation induced by oxidative stress, which ameliorated the metabolic disorder of chondrocytes and other multiple pathological processes triggered by ferroptosis. Moreover, imaging and histopathological analysis of the destabilization of the medial meniscus model in mice confirmed that ES NDs exhibiting significant therapeutic effects in relieving OA. The intra-articular delivery of ES NDs represents a promising approach for treating OA and other joint inflammatory diseases.

Physiatry for Treating Hip, Knee, and Back Pain

Physical Medicine and Rehabilitation (PM&R) is a rapidly expanding field. Physicians who practice PM&R are known as physiatrists and provide care primarily for patients who have disabilities or physical impairments affecting the musculoskeletal system, brain, and spinal cord. Physiatrists may work in an inpatient or outpatient setting, with outpatient physiatrists being an invaluable resource in treating patients experiencing pain. It is worthwhile to refer patients experiencing hip, knee, or back pain to a PM&R specialist because of their skill in making specific and accurate diagnoses, as well as providing a wide range of modalities to treat pain and augment function such as management of pain medications, osteopathic manipulative therapy, trigger point injections, intra-articular steroid injections, orthobiologic therapy, and interventional spinal procedures. Emphasis is on the use of the least invasive modality before employing more invasive treatments. The need for physiatrists to help individuals maximize function and enhance quality of life is increasing with the aging population, expanding workforce of older adults, and a growing population of people with a disability, especially since the COVID-19 pandemic.

Adeno-Associated Virus-Delivered Fibroblast Growth Factor 18 Gene Therapy Promotes Cartilage Anabolism

OBJECTIVE

To determine the characterization of chondrogenic properties of adeno-associated virus type 2 (AAV2)-delivered hFGF18, via analysis of effects on primary human chondrocyte proliferation, gene expression, and in vivo cartilage thickness changes in the tibia and meniscus.

DESIGN

Chondrogenic properties of AAV2-FGF18 were compared with recombinant human FGF18 (rhFGF18) in vitro relative to phosphate-buffered saline (PBS) and AAV2-GFP negative controls. Transcriptome analysis was performed using RNA-seq on primary human chondrocytes treated with rhFGF18 and AAV2-FGF18, relative to PBS. Durability of gene expression was assessed using AAV2-nLuc and in vivo imaging. Chondrogenesis was evaluated by measuring weight-normalized thickness in the tibial plateau and the white zone of the anterior horn of the medial meniscus in Sprague-Dawley rats.

RESULTS

AAV2-FGF18 elicits chondrogenesis by promoting proliferation and upregulation of hyaline cartilage-associated genes, including COL2A1 and HAS2, while downregulating fibrocartilage-associated COL1A1. This activity translates to statistically significant, dose-dependent increases in cartilage thickness in vivo within the area of the tibial plateau, following a single intra-articular injection of the AAV2-FGF18 or a regimen of 6 twice-weekly injections of rhFGF18 protein relative to AAV2-GFP. In addition, we observed AAV2-FGF18-induced and rhFGF18-induced increases in cartilage thickness of the anterior horn of the medial meniscus. Finally, the single-injection AAV2-delivered hFGF18 offers a potential safety advantage over the multi-injection protein treatment as evidenced by reduced joint swelling over the study period.

CONCLUSION

AAV2-delivered hFGF18 represents a promising strategy for the restoration of hyaline cartilage by promoting extracellular matrix production, chondrocyte proliferation, and increasing articular and meniscal cartilage thickness in vivo after a single intra-articular injection.

Non-operative Treatment Options for Osteoarthritis in the Hip

With the increased disability associated with osteoarthritis (OA) progression, and the significant socioeconomic burden of joint replacement surgeries, there is a need for more reliable conservative treatments for patients presenting with hip OA. Most studies of OA treatments involve the knee. We conducted a literature search and reviewed non-operative hip OA treatment recommendations by the Osteoarthritis Research Society International, the American College of Rheumatology, American Academy of Orthopedic Surgeons, and European Alliance of Associations for Rheumatology, as well as Cochrane Reviews. Non-steroidal anti-inflammatory drugs and corticosteroid injections are the most supported and recommended options for hip OA; other medications with potential benefits for short-term pain relief include acetaminophen and tramadol. Most societies recommend against the use of glucosamine, typical opioids, and viscosupplementation injections. Platelet-rich plasma has potential benefits, but evidence of its effectiveness is incomplete. Further research is needed to better inform and guide clinicians who create treatment plans for patients with symptomatic hip OA.

The Effects of Ultrasound-Guided Intra-Articular Injections with Hyaluronic Acid and Corticosteroids in Patients with Hip Osteoarthritis: A Long-Term Real-World Analysis

Intra-articular (IA) ultrasound-guided hip injections are currently considered a cornerstone of the conservative management of symptomatic hip osteoarthritis (HOA), although their effect on clinical outcomes has not been fully elucidated.The purpose of this study is to investigate the effectiveness of ultrasound-guided IA hip injections of hyaluronic acid (HA) with or without corticosteroids (CS) on pain relief and functional improvement in patients with HOA. In total, 167 patients with HOA were assessed at baseline (T0) and 12 months after injection (T1) using the VAS and GLFS scores. The sample consisted mainly of female subjects (58.1%), presenting an average age of 70.6 ± 12.2 years and grade 3 HOA (63.9%) according to the Kellgren-Lawrence classification. Most of the patients (76.2%) underwent unilateral hip injection with a combination of medium-high molecular weight HA (1500-2000 kDa) and CS. At T1, lower use of anti-inflammatory drugs, an increase in the consumption of chondroprotectors, and an overall reduction of instrumental physical therapies and therapeutic exercise were recorded. In addition, a statistically significant intragroup and between-group decrease observed at T1 for both the VAS and GLFS. Study results suggested that intra-articular hip injections with HA alone and with CS could represent a useful therapeutic tool for pain reduction and functional improvement for patients with hip osteoarthritis.

Recommendations for the management of hip and knee osteoarthritis: A systematic review of clinical practice guidelines

OBJECTIVES

Guideline adherence for hip and knee osteoarthritis management is often poor, possibly related to the quality and/or inconsistent recommendations. This systematic review of hip and knee osteoarthritis guidelines aimed to appraise the quality and consistency in recommendations across higher-quality guidelines.

METHODS

Eight databases, guideline repositories, and professional associations websites were searched on 27/10/2022. Guideline quality was appraised using the Appraisal of Guidelines for Research and Evaluation II (AGREE II tool) (six domains). Higher quality was defined as scoring ≥60% for domains 3 (rigour of development), 6 (editorial independence), plus one other. Consistency in recommendations across higher-quality guidelines was reported descriptively. This review was registered prospectively (CRD42021216154).

RESULTS

Seven higher-quality and 18 lesser-quality guidelines were included. AGREE II domain scores for higher-quality guidelines were > 60% except for applicability (average 46%). Higher-quality guidelines consistently recommended in favour of education, exercise, and weight management and non-steroidal anti-inflammatory drugs (hip and knee), and intra-articular corticosteroid injections (knee). Higher quality guidelines consistently recommended against hyaluronic acid (hip) and stem cell (hip and knee) injections. Other pharmacological recommendations in higher-quality guidelines (e.g., paracetamol, intra-articular corticosteroid (hip), hyaluronic acid (knee)) and adjunctive treatments (e.g., acupuncture) were less consistent. Arthroscopy was consistently recommended against in higher-quality guidelines. No higher-quality guidelines considered arthroplasty.

CONCLUSION

Higher-quality guidelines for hip and knee osteoarthritis consistently recommend clinicians implement exercise, education, and weight management, alongside consideration of Non-Steroidal Anti-Inflammatory Drugs and intra-articular corticosteroid injections (knee). Lack of consensus on some pharmacological options and adjunctive treatments creates challenges for guideline adherence. Future guidelines must prioritise providing implementation guidance, considering consistently low applicability scores.

Intra-articular autologous conditioned serum and triamcinolone injections in patients with knee osteoarthritis: a controlled, randomized, double-blind study

OBJECTIVE

This study was performed to assess the impact of autologous conditioned serum (ACS) when added to preceding intra-articular glucocorticoid therapy on pain, function, and quality of life outcomes over 24 weeks.

METHODS

In this single-center, randomized controlled trial involving 40 patients with advanced knee osteoarthritis (Kellgren-Lawrence grades III and IV), ACS or saline placebo was injected after 40 mg triamcinolone acetonide (TA) intra-articular injection. Numerical rating scale (NRS) pain scores and Knee Injury and Osteoarthritis Outcome Score (KOOS) assessments were conducted at baseline and at weeks 3, 6, 12, and 24. The primary endpoint was the change in KOOS Pain at 24 weeks. Patient safety events were also monitored.

RESULTS

At week 24, TA + ACS significantly improved KOOS Pain, Symptoms, Activities of Daily Living, Quality of Life, and KOOS Sport scores. TA + ACS also outperformed TA + placebo in NRS pain scores (average and maximum intensity) at week 24 and NRS pain score (at rest) at weeks 12 and 24. The TA injection followed by ACS or placebo was well-tolerated.

CONCLUSION

ACS adds long-term pain relief and functional improvement to the short-term pain relief provided by glucocorticoids.

Methods of Conservative Intra-Articular Treatment for Osteoarthritis of the Hip and Knee

BACKGROUND

Osteoarthritis is a degenerative joint disease that is becoming increasingly common as the population ages. Conservative treatment for hip or knee osteoarthritis has been limited to pain control. Intra-articular injections for targeted local treatment have been widely used in clinical practice for many years.

METHODS

This review is based on publications retrieved by a selective literature search, including recent meta-analyses, systematic reviews, randomized controlled trials (RCTs), and current guidelines.

RESULTS

In Germany, the 12-month prevalence of osteoarthritis in adults is 17.9%. Conservative treatments are intended to alleviate symptoms and do not affect the progression of the disease. Glucocorticoids can be used to relieve otherwise intractable pain in the short term, but their prolonged use increases the risk of cartilage loss and progression of osteoarthritis. According to multiple guidelines, there is only weak evidence for the use of hyaluronic acid. Evidence does exist that high-molecular-weight hyaluronic acid may lead to better outcomes than the low-molecular-weight form. RCTs have revealed no more than short-term clinical efficacy for a variety of specific therapeutic approaches, including the use of cytokine inhibitors. Other treatments, e.g., with platelet-enriched plasma, aspirates from bone marrow or adipose tissue, or expanded mesenchymal stromal cells (MSC), have not been found to have clinically relevant long-term effects.

CONCLUSION

In view of the scant available evidence, further standardized RCTs will be needed to give a more comprehensive picture of the efficacy of intra-articular treatments for hip and knee osteoarthritis.

What Is the Efficacy of Intra-articular Injections in the Treatment of Ankle Osteoarthritis? A Systematic Review

BACKGROUND

Ankle osteoarthritis (OA) is painful and can impact a patient's physical and mental quality of life. Although intra-articular injections are commonly used to alleviate symptoms, there is conflicting evidence concerning their efficacy. Therefore, an updated systematic review would be informative.

QUESTION/PURPOSE

In this systematic review, we asked: Are there clinically important benefits or harms associated with the use of intra-articular injections in the treatment of ankle OA?

METHODS

We used PubMed, Embase, and the Cochrane Library to search for randomized controlled trials on intra-articular injections for the treatment of ankle OA in June 2021, and updated the search in January 2022; eligible dates were from the date of inception of each database through January 2022. Reference lists of eligible studies and previous reviews were manually screened. Two reviewers independently assessed studies for eligibility. We included seven studies. Three compared hyaluronic acid (HA) with saline, one compared HA with exercise, one compared four different regimens of HA [ 34 ], one compared platelet-rich plasma (PRP) with saline, and one compared botulinum toxin Type A (BoNT-A) with HA. A total of 340 patients were included: 141 in the HA arms, 48 in the PRP arm, 38 in the BoNT-A arm, and 113 in the saline arms. Across all studies, the mean age was 52 ± 21 years, and 35% were women (119 of 340 patients). Methodologic quality was assessed using the Cochrane Risk of Bias 2.0 tool. Of the included studies, the risk of bias was low in two studies, presented some concerns in one study, and was high in four studies. According to the Grading of Recommendations Assessment, Development, and Evaluation methodology, the level of evidence was very low for HA, moderate for PRP, and very low for BoNT-A. The level of heterogeneity was high, and we opted to perform a systematic review rather than a meta-analysis. A clinically relevant difference was based on whether the between-group difference surpassed the cutoff point determined as the minimum clinically important difference.

RESULTS

No clinically relevant differences were found among HA, PRP, and BoNT-A and their control groups at 3, 6, or 12 months. No studies reported any serious adverse events in any treatment group.

CONCLUSION

Given the lack of observed efficacy in this systematic review, these treatments should not be used in practice until or unless future high-quality studies find evidence of efficacy.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Debate: Intra-articular steroid injections for osteoarthritis - harmful or helpful?☆,☆☆

Intra-articular corticosteroids injections are a widely used treatment for pain from symptomatic osteoarthritis. Systematic reviews show that the treatment effect is modest compared with intra-articular saline (often considered as placebo) and lasts for 2-4 weeks on average. Potentially as a consequence of limited therapeutic duration, repeated injections are often given up to 4 injections annually. In this context of repeat injections, recent evidence has emerged that intra-articular corticosteroids might be associated with more MRI-assessed quantitative cartilage thickness loss than saline injections. Guidelines vary in the recommendation for use of intra-articular corticosteroids. Given the frequency with which intra-articular corticosteroids injections are used, the size and scale of the population with osteoarthritis, it is critical to fully understand the benefits and drawbacks of intra-articular corticosteroids injections. That is the focus of this debate article.

Current evidence on mesenchymal stem cells for hip osteoarthritis: a narrative review

There are limited data on the use of mesenchymal stem cell injections for hip osteoarthritis. The goal of this study was to evaluate the literature by analyzing outcomes and comparing methodologies. Online search of PubMed, SportsDiscus and Case Reports Keywords was completed using the keywords 'stem cells' and 'hip' and 'osteoarthritis'. Six studies met the inclusion and exclusion criteria. Five out the six studies had statistically significant improvement in patient reported outcomes after mesenchymal stem cell injections. Only two studies provided information on radiological changes and findings were positive. None of the studies reported major complications. Small series of non-randomized controlled trials completed to date in the use of mesenchymal stem cells for the treatment of hip osteoarthritis reported the procedures to be safe and provide a positive clinical response. Randomized controlled trials must be performed to further confirm mesenchymal stem cells as a treatment option for hip osteoarthritis.

Reduction of systemic exposure and side effects by intra-articular injection of anti-inflammatory agents for osteoarthritis: what is the safer strategy?

Osteoarthritis (OA) is a chronic degenerative joint disease associated with pain, inflammation, and cartilage degradation. However, no current treatment can effectively halt the progression of the disease. Therefore, the use of NSAIDs and intra-articular corticosteroids is usually recommended as the primary treatment for OA-associated pain and inflammation. However, there is accumulating evidence that the long-term use of oral NSAIDs and intra-articular corticosteroids can lead to a myriad of negative side effects. Although numerous efforts have been made to develop intra-articular formulations for NSAIDs, the systemic exposure of intra-articular injection of NSAIDs and its potential side effects have not been explicitly investigated. To ascertain the evident and potential side effects of intra-articular injection of anti-inflammatory agents, we have summarised in this review the systemic exposure, local side effects, and systemic side effects of intra-articular injections of anti-inflammatory agents, including NSAIDs and corticosteroids. For developing a safer treatment to fulfil the unmet long-term use needs of patients, a new therapy, which combines the locally active drug and a sustained-release formulation, has been proposed in this review.

Baseline Knee Pain Predicts Long-Term Response of Intra-Articular Steroid Injection in Symptomatic Knee Osteoarthritis: Data from OAI

OBJECTIVE

The current study aims to investigate the factors that could predict response to intra-articular corticosteroid injection (IACI) in patients with knee osteoarthritis (KOA).

METHODS

Data of participants were retrieved from the Osteoarthritis Initiative database. Participants with at least one IACI treatment on single or bilateral knees within the first 5 years of follow-up were retrospectively included. Demographic data, clinical and radiographic variables were collected at both baseline and the first follow-up after IACI treatment. Positive response to IACI treatment was defined as >20% reduction of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score from V0 to V1. All the variables with P < 0.2 after the comparison between the response and non-response groups were included in a multivariable logistic regression model to identify independent response predictive patient-specific valuables. Receiver operating characteristic curves were performed to establish the cutoff values of independent predictors.

RESULTS

The current study included a total of 385 participants (473 knees), with 155 and 318 knees classified into the response group and non-response group, respectively. Those with satisfied responses to IACI treatment had significantly higher WOMAC pain score (P < 0.001), disability score (P = 0.002), and stiffness score (P = 0.015) at the baseline. Baseline WOMAC pain score showed significant association with positive response to IACI treatment in multivariate logistic analysis and the best cutoff value was 5 points. The rate of analgesics utilization was lower (P = 0.014) in the response group than the non-response group after the IACI treatment.

CONCLUSION

KOA patients with a baseline WOMAC pain score ≥5 are more likely to benefit from IACI treatment.

Joint interventions in osteoarthritis

Osteoarthritis (OA) is among the most common diseases affecting both axial and appendicular joints and the lead cause of disability worldwide. OA incidence is rising due to extended life expectancy and the increasing obesity epidemic. Several joint interventions are available to manage pain and joint function in patients with OA, most of these treatments being widely applied using intra-articular injections. In this chapter, we will describe the different joint interventions available for the management of pain in OA focusing on intra-articular injections, including discussion on the evidence regarding the efficacy of these treatments, based on the most recent systematic reviews and meta-analyses available. We also discuss the importance of imaging in guiding these treatments, including the different imaging modalities available for intra-articular injection guidance, their advantages, and disadvantages. Finally, we briefly discuss safety data and the consensus regarding the most used intra-articular treatments to manage pain in OA.

A Randomized Trial of Intra-articular Injection Therapy for Knee Osteoarthritis

BACKGROUND

Intra-articular injections are widely used for conservative treatment of knee osteoarthritis (OA). However, rigorous data are lacking regarding the comparative therapeutic effectiveness of these injections.

PURPOSE

The aim of this study was to compare clinical outcomes after intra-articular injections of glucocorticoid, hyaluronic acid, platelet-rich plasma (PRP), or placebo in patients with mild or moderate OA of the knee.

MATERIALS AND METHODS

In a double-blinded, placebo-controlled, single-center trial, we randomly assigned knees with early- to middle-stage knee OA (Kellgren-Lawrence grade 1-3) to an intra-articular injection with one of these substances: glucocorticoid, hyaluronic acid, PRP, or placebo. Primary outcome was pain reduction within 6 months after the injection, assessed with the numeric rating scale (NRS; range, 0-100). Secondary outcome parameters included WOMAC scores, Tegner Activity Scale, knee mobility, and adverse events. Finally, a linear mixed-effects model was calculated and corrected for possible patient and covariate effects.

RESULTS

One hundred twenty knees (30 knees per treatment group) in 95 patients (41 female) were included in the final analysis. The median age of patients was 60 years (interquartile range, 54.0-68.0). There was no evidence that the drug effects of primary and secondary outcome parameters differed over time. The median pain at baseline was 32.5 (interquartile range, 15.00-50.00) on NRS. The changes in pain level during the first 6 months compared with baseline were small (within ±5 points on NRS), whereas the intrapatient variability was large between -20 and +20 points. Secondary outcome parameters did not differ significantly among the groups. Kellgren-Lawrence grade did not have a statistically significant effect on pain reduction ( P = 0.61).

CONCLUSIONS

There is no evidence that knee injections with glucocorticoid, PRP, or hyaluronic acid have superior short- or long-term effects in patients with low pain level at baseline and early- to middle-stage knee OA when compared with placebo.

Innovation in Targeted Intra-articular Therapies for Osteoarthritis

Osteoarthritis is the most common chronic joint disease characterized by progressive damage to the joints, leading to pain and loss of function. There is currently no cure or disease-modifying therapy for osteoarthritis. Hence, the increasing disease prevalence linked with ageing and obesity represents a substantial socio-economic burden. Intra-articular therapy by injection of drugs into affected joints can optimize local drug bioavailability, while reducing risks of systemic toxicity, a concern in an ageing patient population. In this review, we investigate the current landscape of intra-articular drug therapies for osteoarthritis, including established approaches and those in clinical development. We performed a literature review using PubMed, complemented with a search for clinical trials using the ClinicalTrials.gov repository. Additionally, conference abstracts and presentations were identified and systematic snowballing was applied. Identified drugs were divided into several groups by main mechanism of action, and include drugs that reduce inflammation (anti-inflammatory), drugs aiming to prevent or reverse structural damage (structure modifying), drugs that aim to reduce the pain, and other drugs with a specific target. Most studies have been performed for osteoarthritis of the knee, a joint that is easily accessible for intra-articular treatments. Optimal therapy would provide symptomatic relief, while preventing further damage to the joint. The field of intra-articular drug therapies for osteoarthritis is rapidly evolving with clear challenges identified: definition of relevant outcome measures, optimization of clinical trial set-ups, and dealing with placebo responses. While many uncertainties persist, it appears that the innovation in drug development and improved clinical trial set-up may finally deliver successful therapies for this important disease.

Ultrasound-responsive hyaluronic acid hydrogel of hydrocortisone to treat osteoarthritis

One of the practical ways to manage the disease flares of arthritis is using an intra-articular depot formulation of glucocorticoids. Hydrogels, as controllable drug delivery systems, are hydrophilic polymers with distinctive properties, such as remarkable water capacity and biocompatibility. This study aimed to design an injectable thermo-ultrasound-triggered drug carrier based on Pluronic® F-127, hyaluronic acid, and gelatin. The in situ hydrogel loaded by hydrocortison was developed and D-optimal design was used to formulate the process. The optimized hydrogel was combined with four different surfactants to better regulate the release rate. In situ gels composed of the hydrocortisone-loaded hydrogel and hydrocortisone-loaded mixed-micelle hydrogel were characterized. The hydrocortisone-loaded hydrogel and selected hydrocortisone-loaded mixed-micelle hydrogel showed a spherical shape and were nano-sized with a unique thermo-responsive nature able to prolong drug release. The ultrasound-triggered release study showed that drug release was time-dependent. By inducing osteoarthritis in a rat model, behavioral tests and histopathological analyses were carried out on the hydrocortisone-loaded hydrogel and a particular hydrocortisone-loaded mixed-micelle hydrogel. In vivo results showed that the selected hydrocortisone-loaded mixed-micelle hydrogel improved the status of the disease. Results highlighted the potential of ultrasound-responsive in situ-forming hydrogels as hopeful formulas for efficient treatment of arthritis.

Musculoskeletal corticosteroid injections: Recommendations of the French Society for Rheumatology (SFR)

Musculoskeletal corticosteroid injections are widely performed, although the exact practice varies greatly due to advances in knowledge and techniques. This justifies updating and drawing up good practice recommendations. Using a consensus model formalized by the French National Authority for Health (HAS) and based on a literature review that resulted in a "white book", 13 recommendations were developed by a group of experts. These recommendations were then sent online to 48 specialists for evaluation, 27 of whom were rheumatologists and 15 of whom were general practitioners. These recommendations were also presented at the 34th annual meeting of the French Society for Rheumatology (SFR) (Paris, December 2021) at a symposium attended by a hundred or so rheumatologists, who voted on these recommendations in person. The results are presented as an overall score out of 10, a median out of 10 and as tertiles. The agreement was excellent for 10 of these 13 recommendations, with mean values of 8.5 to 9.1 out of 10, median values of 9 or 10 out of 10 and agreement of 91.7% to 97.9%, which corresponds to a consensus. The 3 other recommendations were broadly supported but were the subject of more debate. One relates to patient information (mean 7.3/10, median 8/10, upper tertile 72.9%) with discussion about the waiting period. Another related to the summary report (mean 8.4/10, median 9, upper tertile 91.7%) with discussions about its content and the need to specify the lot number of the injected product. The last one related to periprosthetic injections and the need to consult and get approval from a specialist (mean 8.0/10, median 8, upper tertile 83.3%) with mostly the general practitioners having reservations. In all, there is a very strong consensus among the musculoskeletal corticosteroid injection experts and specialists consulted, which justifies them being taken into consideration to improve our daily practice.

Bardoxolone methyl ameliorates osteoarthritis by inhibiting osteoclastogenesis and protecting the extracellular matrix against degradation

Inflammation and oxidative damage are closely related to the development of osteoarthritis. Bardoxolone methyl (CDDO-Me), a semisynthetic oleanane triterpenoid, plays a strong anti-inflammatory and antioxidant role. The purpose of our research was to explore fundamental mechanisms of CDDO-Me in orthopaedics development. The results showed that CDDO-Me inhibited nuclear factor-κB ligand (RANKL)-induced osteoclast formation and extracellular matrix (ECM) degradation by activating the Nrf2/HO-1 signaling pathways and inhibiting NF-κB pathway activation and excess ROS production. In vivo, CDDO-Me significantly attenuated articular cartilage proteoglycan loss and the number of TRAP-positive osteoclasts in a destabilized medial meniscus (DMM) mouse model of OA. Taken together, these data demonstrate that CDDO-Me inhibits osteoclastogenesis and ECM degradation, underscoring its potential therapeutic value in treating OA.

Efficacy, Safety, and Accuracy of Intra-articular Therapies for Hand Osteoarthritis: Current Evidence

The lifetime risk of symptomatic hand osteoarthritis (OA) is 39.8%, with one in two women and one in four men developing the disease by age 85 years and no disease-modifying drug (DMOAD) available so far. Intra-articular (IA) therapy is one of the options commonly used for symptomatic alleviation of OA disease as it can circumvent systemic exposure and potential side effects of oral medications. The current narrative review focuses on the efficacy and safety profiles of the currently available IA agents in hand OA (thumb-base OA or interphalangeal OA) such as corticosteroids and hyaluronic acid (HA), as well as the efficacy and safety of IA investigational injectates in phase 2/3 clinical trials such as prolotherapy, platelet-rich plasma, stem cells, infliximab, interferon-? and botulinum toxin, based on the published randomized controlled trials on PubMed database. The limited published literature revealed the short-term symptomatic benefits of corticosteroids in interphalangeal OA while long-term data are lacking. Most of the short-term studies showed no significant difference between corticosteroids and hyaluronic acid in thumb-base OA, usually with a faster onset of pain relief in the corticosteroid group and a slower but greater (statistically insignificant) pain improvement in the HA group. The majority of studies in investigational agents were limited by small sample size, short-term follow-up, and presence of serious side effects. In addition, we reported higher accuracy rates of drug administrations under imaging guidance than landmark guidance (blind method), and then briefly describe challenges for the long-term efficacy and prospects of IA therapeutics.

Effects of medications on incidence and risk of knee and hip joint replacement in patients with osteoarthritis: a systematic review and meta-analysis

Background

This systematic review and meta-analysis aimed to investigate the incidence and risk of knee and hip replacement in patients with osteoarthritis (OA) treated with different medications.

Methods

OVID MEDLINE, OVID EMBASE, Cochrane and Web of Science electronic databases were searched from inception to May 4th, 2022. Clinical trials, including randomized controlled trials, cohort studies and case–control studies, were selected. The meta-analysis effect size was estimated using either incidence with 95% confidence intervals (CIs) or odds ratio (OR)/relative risk (RR) with 95% CIs. The risk of bias and heterogeneity among studies were assessed and analyzed.

Results

Forty studies were included, involving 6,041,254 participants. The incidence of joint replacement in patients with OA varied according to the study design and treatments. The incidence of knee arthroplasty varied from 0 to 70.88%, while the incidence of hip arthroplasty varied from 11.71 to 96.43%. Compared to non-users, bisphosphonate users had a reduced risk of knee replacement (RR = 0.71, 95% CI: 0.66–0.77; adjusted hazard ratio [aHR] = 0.76, 95% CI: 0.70–0.83). Compared to intra-articular corticosteroid users, hyaluronic acid (HA) users had a higher risk of knee arthroplasty (RR = 1.76, 95% CI: 1.38–2.25). No publication bias was observed.

Conclusions

Bisphosphonate treatment is associated with a reduced risk of knee replacement. More studies are needed to validate our results due to the limited number of eligible studies and high heterogeneity among studies.

Interventional Therapies for Osteoarthritis: An Update

Osteoarthritis (OA) is one of the most common diseases worldwide and is expected to increase in incidence as the age of the general population rises. Both oral medications, such as NSAIDs, and surgical treatments used for OA management have limitations. Demand is rising for minimally invasive techniques such as intraarticular injections and percutaneous interventions for use in place of or in conjunction with oral medications and surgical therapies, and the past 2 decades have seen a rapid expanse in both pharmacologic and nonpharmacologic minimally invasive OA treatments. Image guidance with fluoroscopy, CT, or ultrasound is often used in conjunction with these procedures to achieve precise treatment localization to achieve maximal therapeutic effect. The choice of modality used for image guidance is often influenced by clinician experience, patient characteristics, and equipment availability. This article reviews the mechanisms of action, contraindications, complications, and efficacy of conventional and developing minimally invasive OA treatments. The minimally invasive treatment options described in this Review include therapeutic injections such as antiinflammatory agents, viscosupplements, and biologics, as well as nonpharmacologic treatments of subchondroplasty, nerve ablation, genicular artery embolization, intraarticular pulsed radiofrequency therapy, and MRI-guided focused ultrasound therapy.

Defining and predicting radiographic knee osteoarthritis progression: a systematic review of findings from the osteoarthritis initiative

PURPOSE

The purposes of this systematic review were to (1) identify the commonly used definitions of radiographic KOA progression, (2) summarize the important associative risk factors for disease progression based on findings from the OAI study and (3) summarize findings from radiographic KOA progression prediction modeling studies regarding the characterization of progression and outcomes.

METHODS

A systematic review was performed by conducting a literature search of definitions, risk factors and predictive models for radiographic KOA progression that utilized data from the OAI database. Radiographic progression was further characterized into "accelerated KOA" and "typical progression," as defined by included studies.

RESULTS

Of 314 studies identified, 41 studies were included in the present review. Twenty-eight (28) studies analyzed risk factors associated with KOA progression, and 13 studies created or validated prediction models or risk calculators for progression. Kellgren-Lawrence (KL) grade based on radiographs was most commonly used to characterize KOA progression (50%), followed by joint space width (JSW) narrowing (32%) generally over 48 months. Risk factors with the highest odds ratios (OR) for progression included periarticular bone mineral density (OR 10.40), any knee injury within 1 year (OR 9.22) and baseline bone mineral lesions (OR 7.92). Nine prediction modeling studies utilized both clinical and structural risk factors to inform their models, and combined models outperformed purely clinical or structural models.

CONCLUSION

The cumulative evidence suggests that combinations of structural and clinical risk factors may be able to predict radiographic KOA progression, particularly in patients with accelerated progression. Clinically relevant and feasible prediction models and risk calculators may provide valuable decision-making support when caring for patients at risk of KOA progression, although standardization in modeling and variable identification does not yet exist.

Hydrogel treatment for idiopathic osteoarthritis in a Dunkin Hartley Guinea pig model

The study objective was to determine if intraarticular injections of an extracellular matrix (ECM) powder and blood composite (ECM-B) would have a significant impact on post-operative gait parameters without eliciting adverse cartilage changes or severe lymphatic reactions in an idiopathic osteoarthritis (OA) model. Twenty-one Dunkin Hartley Guinea pigs received an intraarticular injection of ECM-B in each knee and were split into sub-groups for gait assessment and post-harvest knee evaluations at 1 week (n = 5), 2 weeks (n = 5), 4 weeks (n = 5), or 8 weeks (n = 6). The results were compared with a control group (n = 5), which underwent bilateral injections of phosphate-buffered saline (PBS), gait measurements at 1, 2, 4, and 8 weeks, and post-mortem knee evaluation at 8 weeks post-injection. Hind limbs and popliteal lymph nodes were collected at the Week 8 endpoint and underwent histological analysis by a veterinary pathologist. Significant improvement in hind limb base of support was observed in the ECM-B group compared to the control group at Week 4 but was no longer significant by Week 8. No significant differences were observed between control and ECM-B groups in hind limb cartilage, synovium, or popliteal lymph node histology at Week 8. In conclusion, administration of an ECM-B material may improve gait for a limited time without significant adverse effects on the cartilage, synovium, or local lymph nodes.

New smokeless moxibustion for knee osteoarthritis: A study protocol for a multicenter, single-blind, randomized controlled trial

INTRODUCTION

Knee osteoarthritis (KOA) is a chronic inflammatory disease with high morbidity and disability. As the aging and obese population increase, so will the medical services for this disease. The purpose of this study is to compare the clinical efficacy of herbal activated carbon smokeless moxibustion and traditional moxibustion in the treatment of KOA and to determine the clinical efficacy of herbal activated carbon smokeless moxibustion in the treatment of KOA.

METHODS/DESIGN

This is a multicenter, two parallel-group, single-blind, randomized controlled trial. Eighty-eight subjects with KOA (Kellgren Lawrence grade II or III) will be recruited and randomly treated with smokeless moxibustion or traditional moxibustion in the ratio of 1:1. The smokeless moxibustion group will use plant herbal activated carbon smokeless moxa cone. The traditional moxibustion group will be treated with pure moxa cone. Subjects in both groups will receive treatment at the affected knee(s) at the acupuncture point ST35, EX-LE2, and EX-LE4. Subjects in both groups will receive 3 sessions per week of moxibustion for 4 weeks. The primary outcome are changes in the Western Ontario and McMaster Universities Osteoarthritis Index pain scores from baseline to week 24. Secondary outcomes include visual analog scale, 50 yards fast walking time, short-form heath survey 36, overall clinical efficacy evaluation, self-assessment of safety, treatment credibility and expectancy, and cytokines related to osteoarthritis in serum.

DISCUSSION

This randomized single-blind controlled trial takes traditional moxibustion as the control group to provide strict evidence for the clinical efficacy and safety of herbal activated carbon smokeless moxibustion in the treatment of KOA.

Medicinal plants and their secondary metabolites in alleviating knee osteoarthritis: A systematic review

BACKGROUND

With the increasing ages of the general population, the incidence of knee osteoarthritis (KOA) is also rising, and KOA has become a major health problem worldwide. Recently, medicinal plants and their secondary metabolites have gained interest due to their activity in treating KOA. In this paper, a comprehensive systematic review of the literature was performed concerning the effects of medicinal plant extracts and natural compounds against KOA in recent years. The related molecular pathways of natural compounds against KOA were summarized, and the possible crosstalk among components in chondrocytes was discussed to propose possible solutions for the current situation of treating KOA.

PURPOSE

This review focused on the molecular mechanisms by which medicinal plants and their secondary metabolites act against KOA.

METHODS

Literature searches were performed in the PUBMED, Embase, Science Direct, and Web of Science databases for a 10-year period from 2011 to 2022 with the search terms "medicinal plants," "bioactive compounds," "natural products," "phytochemical," "knee osteoarthritis," "knee joint osteoarthritis," "knee osteoarthritis," "osteoarthritis of the knee," and "osteoarthritis of knee joint."

RESULTS

According to the results, substantial plant extracts and secondary metabolites show a positive effect in fighting KOA. Plant extracts and their secondary metabolites can affect the diagnostic and prognostic biomarkers of KOA. Natural products inhibit the expression of MMP1, MMP3, MMP19, syndecan IV, ADAMTS-4, ADAMTS-5, iNOS, COX-2, collagenases, IL-6, IL-1β, and TNF-α in vitro and in vivo and . Cytokines also upregulate the expression of collagen II and aggrecan. The main signaling pathways affected by the extracts and isolated compounds include AMPK, SIRT, NLRP3, MAPKs, PI3K/AKT, mTOR, NF-κB, WNT/β-catenin, JAK/STAT3, and NRF2, as well as the cell death modes apoptosis, autophagy, pyroptosis, and ferroptosis.

CONCLUSION

The role of secondary metabolites in different signaling pathways supplies a better understanding of their potential to develop further curative options for KOA.

Consensus Guidelines on Interventional Therapies for Knee Pain (STEP Guidelines) from the American Society of Pain and Neuroscience

Knee pain is second only to the back as the most commonly reported area of pain in the human body. With an overall prevalence of 46.2%, its impact on disability, lost productivity, and cost on healthcare cannot be overlooked. Due to the pervasiveness of knee pain in the general population, there are no shortages of treatment options available for addressing the symptoms. Ranging from physical therapy and pharmacologic agents to interventional pain procedures to surgical options, practitioners have a wide array of options to choose from – unfortunately, there is no consensus on which treatments are “better” and when they should be offered in comparison to others. While it is generally accepted that less invasive treatments should be offered before more invasive ones, there is a lack of agreement on the order in which the less invasive are to be presented. In an effort to standardize the treatment of this extremely prevalent pathology, the authors present an all-encompassing set of guidelines on the treatment of knee pain based on an extensive literature search and data grading for each of the available alternative that will allow practitioners the ability to compare and contrast each option.

Comparing the Efficacy of Intra-Articular Single Platelet-Rich Plasma(PRP) versus Novel Crosslinked Hyaluronic Acid for Early-Stage Knee Osteoarthritis: A Prospective, Double-Blind, Randomized Controlled Trial

Background and Objectives: For the treatment of knee osteoarthritis (OA), intra-articular platelet-rich plasma (PRP) and novel crosslinked single-dose hyaluronic acid (HA) have both been reported to improve outcomes, but no study has compared them for the treatment of knee OA. We hypothesized patients with early-stage knee OA who received PRP injections would have more WOMAC score changes than those who received HA injections. This is the first prospective, double-blind, parallel, randomized controlled trial comparing the efficacy of intra-articular single-dose PRP versus novel crosslinked HA (HyajointPlus) for treating early-stage knee OA. Materials and Methods: This study analyzed 110 patients randomized into the PRP (n = 54) or HA (n = 56) groups. The primary outcome is the change of WOMAC score at 1-, 3-, and 6-month follow-ups compared to baseline. Results: The data revealed significant improvements in all WOMAC scores in the PRP group at 1-, 3-, and 6-month follow-up visits compared with the baseline level except for the WOMAC stiffness score at the 1-month follow up. In the HA group, significant improvements were observed only in the WOMAC pain score for all the follow-up visits and in WOMAC stiffness, function, and total scores at 6-month follow-up. When comparing the change of WOMAC score at 1-, 3-, and 6-month follow-ups, no significant differences were found between PRP and HA group. Conclusions: This study revealed that both PRP and HA can yield significant improvements in WOMAC scores at 6-month follow-up without any between-group differences at 1-, 3-, and 6-month follow-ups. Thus, both the single-injection regimens of PRP and HA can improve the functional outcomes for treating early-stage knee OA.

Externally validated models for first diagnosis and risk of progression of knee osteoarthritis

OBJECTIVE

We develop and externally validate two models for use with radiological knee osteoarthritis. They consist of a diagnostic model for KOA and a prognostic model of time to onset of KOA. Model development and optimisation used data from the Osteoarthritis initiative (OAI) and external validation for both models was by application to data from the Multicenter Osteoarthritis Study (MOST).

MATERIALS AND METHODS

The diagnostic model at first presentation comprises subjects in the OAI with and without KOA (n = 2006), modelling with multivariate logistic regression. The prognostic sample involves 5-year follow-up of subjects presenting without clinical KOA (n = 1155), with modelling with Cox regression. In both instances the models used training data sets of n = 1353 and 1002 subjects and optimisation used test data sets of n = 1354 and 1003. The external validation data sets for the diagnostic and prognostic models comprised n = 2006 and n = 1155 subjects respectively.

RESULTS

The classification performance of the diagnostic model on the test data has an AUC of 0.748 (0.721-0.774) and 0.670 (0.631-0.708) in external validation. The survival model has concordance scores for the OAI test set of 0.74 (0.7325-0.7439) and in external validation 0.72 (0.7190-0.7373). The survival approach stratified the population into two risk cohorts. The separation between the cohorts remains when the model is applied to the validation data.

DISCUSSION

The models produced are interpretable with app interfaces that implement nomograms. The apps may be used for stratification and for patient education over the impact of modifiable risk factors. The externally validated results, by application to data from a substantial prospective observational study, show the robustness of models for likelihood of presenting with KOA at an initial assessment based on risk factors identified by the OAI protocol and stratification of risk for developing KOA in the next five years.

CONCLUSION

Modelling clinical KOA from OAI data validates well for the MOST data set. Both risk models identified key factors for differentiation of the target population from commonly available variables. With this analysis there is potential to improve clinical management of patients.

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

PURPOSE

To evaluate various radiofrequency ablation (RFA) treatments for knee osteoarthritis (OA) and determine the best modality, target, number of electrodes, and image guidance for improving knee pain and function.

METHODS

Electronic databases were searched for randomized controlled trials (RCTs) comparing the efficacy of RFA treatments for knee OA from inception up to September 30, 2021. The primary outcome was the visual analog scale (VAS), and the secondary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Bayesian network meta-analysis was performed to synthesize the mean difference (MD) and rank the comparative effectiveness of treatments.

RESULTS

A total of 21 eligible RCTs (from 2011 to 2021, involving 1,818 patients) with 8 RFA treatments, 6 intra-articular injections, NSAIDS, exercise, and placebo were assessed. Conventional bipolar genicular nerve RFA (GNRFA) had the greatest net benefit on the VAS at 6 months (MD, -5.5; 95% confidence interval [CI], -4.3 to -6.7; SUCRA, .98). And cooled monopolar GNRFA had the greatest net benefit on the WOMAC at 6 months (MD, -33; 95% CI, -37 to -29; SUCRA, .99). In conventional and pulsed modalities, bipolar RFA was associated with a significant decrease in VAS and WOMAC than monopolar RFA. Combining pulsed intra-articular RFA and platelet-rich plasma injection had no additional positive effects on VAS or WOMAC at 3 months.

CONCLUSIONS

RFA is effective in improving both knee pain and function in patients with OA, at least in the short term (6 months). Patients respond better to the cooled modality than the conventional and pulsed modalities. Bipolar is more effective than monopolar for improving pain and function in conventional and pulsed modalities. Fluoroscopy and ultrasound guidance showed no differences in improving pain and function. The effectiveness of RFA in cooled modality using bipolar or in combination with various intra-articular injections remains to be compared.

LEVEL OF EVIDENCE

II, systematic review and meta-analysis of Level I and II studies.

Cooled radiofrequency ablation of genicular nerves provides 24-Month durability in the management of osteoarthritic knee pain: Outcomes from a prospective, multicenter, randomized trial

Objective

To assess long‐term outcomes of cooled radiofrequency ablation (CRFA) of genicular nerves for chronic knee pain due to osteoarthritis (OA).

Methods

A prospective, observational extension of a randomized, controlled trial was conducted on adults randomized to CRFA. Subjects were part of a 12‐month clinical trial comparing CRFA of genicular nerves to a single hyaluronic injection for treatment of chronic OA knee pain, who then agreed to visits at 18‐ and 24‐months post CRFA and had not undergone another knee procedure since. The subjects were evaluated for pain using the Numeric Rating Scale (NRS) function using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), subjective benefit using the Global Perceived Effect (GPE) scale, quality of life using the EuroQol‐5‐Dimensions‐5 Level (EQ‐5D‐5L) questionnaire, and safety.

Results

Of 57 subjects eligible, 36 enrolled; 32 completed the 18‐month visit with a mean NRS score of 2.4 and 22 (69%) reporting ≥50% reduction in pain from baseline (primary endpoint); 27 completed the 24‐month visit, with a mean NRS of 3.4 and 17 (63%) reporting ≥50% pain relief. Functional and quality of life improvements persisted similarly, with mean changes from baseline of 53.5% and 34.9% in WOMAC total scores, and 24.8% and 10.7% in EQ‐5D‐5L Index scores, at 18‐ and 24‐months, respectively. There were no identified safety concerns in this patient cohort.

Conclusion

In this subset of subjects, CRFA of genicular nerves provided durable pain relief, improved function, and improved quality of life extending to 24 months post procedure, with no significant safety concerns.

A Comprehensive Update of Prolotherapy in the Management of Osteoarthritis of the Knee

This is a comprehensive review of the literature focusing on the use of prolotherapy in the treatment of osteoarthritis of the knee. It covers the background, efficacy, and advantages of prolotherapy in the management of osteoarthritis symptoms and then covers the existing evidence of the use of prolotherapy for this purpose. Current treatments for osteoarthritis of the knee are numerous, yet patients continue to endorse chronic pain and poor quality of life. Prolotherapy is a treatment that has been inadequately studied with poor sample sizes and lack of standardization between trials. However, in recent years the literature on prolotherapy in the treatment of knee osteoarthritis has grown. Although there is still a lack of homogeneity, trials have shown that dextrose prolotherapy, autologous conditioned serum, hyaluronic injections, and normal saline administered either intra- or peri-articularly are comparable in reducing pain scores to other primary treatment options. The mechanism of action for prolotherapy is still unclear, but researchers have found that prolotherapy plays some role in cartilage growth or chondrogenesis and has been shown to have improved radiographic outcomes. Prolotherapy appears to be a safe treatment alternative that has been shown to improve stiffness, pain, function, and quality of life in osteoarthritis of the knee. Knee osteoarthritis is remarkably prevalent in the United States and is one of the most common causes of disability in the elderly population. Although there are many treatment options, patients continue to live with chronic pain which can incur high costs for patients. A safe, long-term, and effective solution has not yet been identified. Prolotherapy has been shown to be a safe option for improving pain, function, and quality of life as effectively as other treatment options.

Cooled radiofrequency ablation of the genicular nerves for chronic pain due to osteoarthritis of the knee: a cost-effectiveness analysis compared with intra-articular hyaluronan injections based on trial data

Background

Effective symptom control in painful knee osteoarthritis (OA) may improve patient quality of life. In a randomised crossover trial (NCT03381248), COOLIEF* cooled radiofrequency ablation (CRFA) reduced pain and stiffness and improved physical function and quality of life compared with intra-articular hyaluronan (HA) injections. The present study aimed to establish the cost effectiveness of CRFA versus intra-articular HA injections for treating moderate-to-severe OA knee pain from a US Medicare perspective.

Methods

We conducted a cost-effectiveness analysis using utility data (EQ-5D) from the randomised crossover trial of CRFA versus intra-articular HA injections, which had follow-ups at 1, 3, 6, and 12 months. Patients in the HA group with unsatisfactory outcomes (e.g., continued pain) at 6 months could cross over to CRFA. Economic analysis outcomes included quality-adjusted life-years (QALYs), costs, and cost effectiveness (cost per QALY gained). Base-case analyses were modelled on a 6-month time horizon (to trial crossover). Due to limited trial data in the HA arm beyond 6 months, scenarios explored potential outcomes to 12 months if: 1) Utility with HA persisted for a further 6 months; 2) A second HA injection was received at 6 months and achieved the same utility change for the second 6 months. In both scenarios, the CRFA arm used trial data for patients who received CRFA from baseline to 12 months. Alternative costing scenarios were also explored.

Results

CRFA resulted in an incremental QALY gain of 0.020 at an incremental cost of US$1707, equating to an incremental cost-effectiveness ratio (ICER) of US$84,392 per QALY over 6 months, versus intra-articular HA injections. Extending the analysis to 12 months and assuming persistence in utility in the HA arm resulted in a larger utility gain for CRFA (0.056 QALYs) and a lower ICER of US$30,275 per QALY. If patients received a second HA injection, the incremental benefit of CRFA out to 12 months was reduced (QALY gain 0.043) but was offset by the costs of the second HA injection (incremental cost US$832). This resulted in an ICER of US$19,316 per QALY.

Conclusions

CRFA is a cost-effective treatment option for patients with OA-related knee pain considering the typical US threshold of US$100,000/QALY.

Intraarticular Steroid Injection in Hip and Knee with Fluoroscopic Guidance: Reassessing Safety

Background Intraarticular corticosteroid (IACS) injections are frequently performed for hip and knee osteoarthritis (OA); however, there are conflicting data about the benefits and complications of IACS injections and a lack of large studies with follow-up. Purpose To determine the number of patients with complications after hip and knee IACS injections in a large study sample with long-term follow-up. Materials and Methods This retrospective single-center case series included patients who received a corticosteroid injection in the hip (n = 500) or knee (n = 500) and who underwent clinical and radiologic follow-up (conventional radiography, fluoroscopy, CT, or MRI) between 1 and 12 months after injection (January 2016 to May 2020). General descriptive statistics and the χ² test were applied. P < .05 was indicative of a significant difference. Results Of the 1000 patients (mean age, 57 years ± 16 [SD]; 545 women), 10 patients (1%) developed severe complications. Four patients developed osteonecrosis; three, insufficiency fractures; and three, rapid progressive OA. All 10 complications occurred between 2 and 9 months after injection: six (60%) in the hip and four (40%) in the knee. Of the included 1000 patients, 545 (54%) were women, but they had nine of the 10 (90%) complications (P = .02). Conclusion Intraarticular steroid injection had a substantially lower complication rate than that reported in previous smaller studies. The rate of severe complications was disproportionally higher in women than in men. © RSNA, 2022 See also the editorial by Jennings in this issue.

Dexamethasone: Insights into Pharmacological Aspects, Therapeutic Mechanisms, and Delivery Systems

Dexamethasone (DEX) has been widely used to treat a variety of diseases, including autoimmune diseases, allergies, ocular disorders, cancer, and, more recently, COVID-19. However, DEX usage is often restricted in the clinic due to its poor water solubility. When administered through a systemic route, it can elicit severe side effects, such as hypertension, peptic ulcers, hyperglycemia, and hydro-electrolytic disorders. There is currently much interest in developing efficient DEX-loaded nanoformulations that ameliorate adverse disease effects inhibiting advancements in scientific research. Various nanoparticles have been developed to selectively deliver drugs without destroying healthy cells or organs in recent years. In the present review, we have summarized some of the most attractive applications of DEX-loaded delivery systems, including liposomes, polymers, hydrogels, nanofibers, silica, calcium phosphate, and hydroxyapatite. This review provides our readers with a broad spectrum of nanomedicine approaches to deliver DEX safely.

Injectable Natural Polymer Hydrogels for Treatment of Knee Osteoarthritis

Osteoarthritis (OA) is a serious chronic and degenerative disease that increasingly occurs in the aged population. Its current clinical treatments are limited to symptom relief and cannot regenerate cartilage. Although a better understanding of OA pathophysiology has been facilitating the development of novel therapeutic regimen, delivery of therapeutics to target sites with minimal invasiveness, high retention, and minimal side effects remains a challenge. Biocompatible hydrogels have been recognized to be highly promising for controlled delivery and release of therapeutics and biologics for tissue repair. In this review, the current approaches and the challenges in OA treatment, and unique properties of injectable natural polymer hydrogels as delivery system to overcome the challenges are presented. The common methods for fabrication of injectable polysaccharide-based hydrogels and the effects of their composition and properties on the OA treatment are detailed. The strategies of the use of hydrogels for loading and release cargos are also covered. Finally, recent efforts on the development of injectable polysaccharide-based hydrogels for OA treatment are highlighted, and their current limitations are discussed.

Risk factors associated with the occurrence of total knee arthroplasty in patients with knee osteoarthritis: a nested case–control study

Objectives:

The aim of this study was to investigate changes over time in osteoarthritis risk factors most closely associated with the occurrence of total knee arthroplasty (TKA). We hypothesize that the robustness of a longitudinal case–control study will provide new information on the association between changes in various clinical and structural parameters in different time frames before TKA.

Methods:

Cases (195; TKA after cohort entry) and controls (468) matched for age, gender, income, WOMAC pain, Kellgren–Lawrence grade and follow-up duration were from the Osteoarthritis Initiative cohort. Associations between changes in sociodemographic, clinical, imaging and osteoarthritis therapies with the occurrence of TKA were performed using conditional logistic regression analyses.

Results:

Worsening of WOMAC scores (cOR 1.02–1.20, p ⩽ 0.012), KOOS (1.02–1.04, p ⩽ 0.014), knee injuries sustained in the previous 30–40 years (women 2.70, p = 0.034) and valgus alignment (1.10, p = 0.052) were associated with the occurrence of TKA. Also associated with TKA was cartilage volume loss in the lateral (overall 1.76, p = 0.025; women 1.93, p = 0.047) and medial compartments (⩾10%, overall 1.54, p = 0.027; men 2.34, p = 0.008), occurrence of medial meniscal extrusion (overall 1.77, p = 0.046; men 2.86, p = 0.028), and increase in bone marrow lesions (BMLs) for women (1.09, p = 0.048). The association of risk factors with TKA was reinforced when both an increase in WOMAC pain and cartilage volume loss (1.85, p = 0.001) were combined. Pain medication usage, mainly narcotics and intra-articular steroid injections (IASI), was also associated with TKA, with no impact on changes in cartilage loss or structure.

Conclusion:

This study provides new information about gender differences in risk factors associated with the occurrence of TKA. Worsening of valgus alignment, cartilage volume loss in the lateral compartment, BMLs and older injuries are important risk factors in women, while medial compartment cartilage loss and meniscal extrusion are in men. The use of pain medication and IASI although associated was found not causal with TKA.