Risk factors and clinical characteristics of deep knee infection in patients with intra-articular injections: A matched retrospective cohort analysis

ASRA Pain Medicine consensus practice infection control guidelines for regional anesthesia and pain medicine

BACKGROUND

To provide recommendations on risk mitigation, diagnosis and treatment of infectious complications associated with the practice of regional anesthesia, acute and chronic pain management.

METHODS

Following board approval, in 2020 the American Society of Regional Anesthesia and Pain Medicine (ASRA Pain Medicine) commissioned evidence-based guidelines for best practices for infection control. More than 80 research questions were developed and literature searches undertaken by assigned working groups comprising four to five members. Modified US Preventive Services Task Force criteria were used to determine levels of evidence and certainty. Using a modified Delphi method, >50% agreement was needed to accept a recommendation for author review, and >75% agreement for a recommendation to be accepted. The ASRA Pain Medicine Board of Directors reviewed and approved the final guidelines.

RESULTS

After documenting the incidence and infectious complications associated with regional anesthesia and interventional pain procedures including implanted devices, we made recommendations regarding the role of the anesthesiologist and pain physician in infection control, preoperative patient risk factors and management, sterile technique, equipment use and maintenance, healthcare setting (office, hospital, operating room), surgical technique, postoperative risk reduction, and infection symptoms, diagnosis, and treatment. Consensus recommendations were based on risks associated with different settings and procedures, and keeping in mind each patient's unique characteristics.

CONCLUSIONS

The recommendations are intended to be multidisciplinary guidelines for clinical care and clinical decision-making in the regional anesthesia and chronic interventional pain practice. The issues addressed are constantly evolving, therefore, consistent updating will be required.

Intra-articular procedures and associated septic arthritis: A mini-review

Native joint septic arthritis (SA) is a severe, potentially life-threatening condition characterized by the invasion of synovial fluid and membrane by pathogens, most commonly bacteria. The rising frequency of intra-articular procedures such as joint aspirations and injections has led to increased concern regarding iatrogenic septic arthritis. This mini-review aims to summarize current understanding of the incidence, risk factors, bacterial etiology, and strategies for preventing SA associated with intra-articular procedures. Recent studies report that while iatrogenic SA incidence remains low, ranging between 0.002% and 0.008% following injections, it is higher following arthroscopy (0.14%). Risk factors for iatrogenic SA mirror those of hematogenous SA, comprising older age, male gender, comorbidities such as diabetes mellitus, and systemic corticosteroid therapy. Staphylococcus aureus remains the most frequently implicated pathogen, followed by coagulase-negative staphylococci and streptococci. Preventive measures, including hand antisepsis, patient skin disinfection, and the wearing of surgical masks, are essential to reducing the risk of SA during intra-articular procedures. Despite low incidence, SA poses significant morbidity and mortality risks, underscoring the need for adherence to infection control protocols. This review highlights the importance of standardized preventive measures and further research into optimized aseptic techniques, the objective being to mitigate the risk of iatrogenic infections in clinical practice.

[Septic musculoskeletal complications under immunomodulating treatment]

Infections are an important cause of morbidity and mortality in patients with inflammatory rheumatic diseases. Among these, musculoskeletal infections represent a relevant proportion as patients with rheumatoid arthritis face an increased risk of developing septic arthritis and prosthesis infections. The causes are multifactorial. In addition to immunosuppressive treatment, risk factors of infection in rheumatoid arthritis (RA) patients include repeated intra-articular joint punctures, an increased rate of joint replacement surgery, damaged joint structure and comorbidities. The use of glucocorticoids and tumor necrosis factor alpha (TNF-alpha) inhibitors, especially in the first 6 months of treatment, increase the risk of septic arthritis and periprosthetic joint infections. In addition, an increased disease activity could also be identified as a risk factor. Under immunosuppressive therapy rare pathogens such as Candida and mycobacteria can cause the infection and should be considered when there is a lack of clinical response to antibiotic treatment.

Asymptomatic Elevated Inflammatory Markers: Is There a Risk for Infection or Revision in Primary Total Knee Arthroplasty?

BACKGROUND

Total knee arthroplasty (TKA) is the treatment of choice for advanced knee osteoarthritis. Long-term studies report high patient satisfaction, while complications such as periprosthetic joint infection (PJI) can be devastating. Knowledge regarding risk factors for PJI is critical to minimize and ideally avoid complications. The purpose of this study was to investigate the risk of PJI and revision in patients who had preoperative asymptomatic high C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) levels in primary TKAs.

METHODS

Patients undergoing primary TKA between 2010 and 2022 were eligible. Inclusion criteria were patients who had preoperative complete biochemical parameters and a minimum follow-up of 12 months. Patients who died during the first year, and those who had a history of inflammatory arthritis, autoimmune disease, renal pathologies, or septic arthritis, were excluded. Patients who had elevated blood CRP and ESR levels taken within 48 hours before surgery underwent a thorough medical examination with a focus on infection symptoms. After screening and consultation, residual elevated CRP and ESR levels were classified as asymptomatic. After exclusions, 1,528 patients were included. The mean age was 66 years (range, 35 to 92), and the mean follow-up time was 6.4 years (range, 1.6 to 12.3).

RESULTS

The rate of revision within one year after surgery was 1.6%, whereas the rate of revision in the first 5 years was 3.8%. The PJI rates for the 1st and 5th postoperative years were 1.7 and 2.9%, respectively. Regression analysis did not show any of the potential variables to be a risk factor for revision or PJI.

CONCLUSIONS

Asymptomatic elevated acute-phase reactants are not a risk factor for periprosthetic joint infection or aseptic revision. At a mean follow-up of 6.4 years, overall survival was 96.7%, with only 2.2% of patients revised due to a PJI.

Intra-articular steroids for the treatment of coxarthrosis; a retrospective cohort study comparing three contrast techniques

INTRODUCTION

Intra-articular steroid injections (IAS) are a treatment for coxarthrosis. This study examines the efficacy of three fluoroscopy-guided IAS contrast techniques for coxarthrosis: contrast-assisted (Iohexol), air arthrogram-assisted and blind (contrast/air free) and stratifies efficacy based on multiple patient variables.

MATERIALS AND METHODS

A cohort of 307 hip IAS was retrospectively analysed over a four-year period. The primary outcome was efficacy of IAS between each technique group, defined by duration of symptomatic relief. The secondary outcome was efficacy based on multiple patient variables. Variables included age, BMI, gender, type of osteoarthritis, grade of osteoarthritis, smoking status, co-morbidity index and duration of pre-injection symptoms. Chi-squared, Pearson, One Way ANOVA and F-tests were used for statistical analysis.

RESULTS

Total failure (< 1 week symptomatic relief) was 20% (contrast 20%, air 14%, blind 26%). >3 months of symptomatic relief was experienced by 35%, with the air arthrogram technique containing the largest proportion of IAS achieving > 3months of relief within its own group (contrast 35%, air 38%, blind 28%). Non-smokers experienced a longer duration of symptomatic relief in the air arthrogram group (p = 0.04). Older patients had a longer duration of symptomatic relief with the blind technique (p = < 0.001). There were no significant differences between the three techniques based on the other patient variables.

CONCLUSION

Air arthrogram is an effective method of confirming injection placement in hip IAS for coxarthrosis and the use of a contrast agent (e.g., Iohexol) may not be required. Non-contrast techniques may produce longer duration of symptomatic relief in non-smokers and in older patients.

How safe are intra-articular corticosteroid injections to the hip?

BACKGROUND

Intra-articular corticosteroid injections (ICSI) are an effective symptomatic treatment for osteoarthritis of the hip. However, the safety of ICSI has been questioned and a relatively high risk for septic arthritis, rapidly progressive osteoarthritis (RPIO) and periprosthetic joint infections (PJI) in patients undergoing subsequent total hip arthroplasty (THA) have been suggested.

METHODS

This is a retrospective evaluation of 682 hips that underwent ICSI with 40 mg of Triamcinolone for primary osteoarthritis of the hip. All ICSI were performed using sterile techniques, the number of ICSI in each hip and the cumulative corticosteroid dosage were assessed. Pre- and post-injection radiographs were compared to identify cases with RPIO. Native joint septic arthritis, surgical site infections and PJI were identified by chart review.

RESULTS

4 hips (0.6%) developed RPIO 2-4 months following ICSI. The cumulative Triamcinolone dose was not associated with the development of RPIO (p = 0.281). 1 case was diagnosed with septic arthritis and treated with staged THA, there were no signs of infection at a 5 years follow-up. 483 hips (75.7%) underwent THA, including 199 hips with THA less than 3 months following ICSI and 181 hips with > 1 ICSI prior to THA. There were 3 superficial surgical site infections/wound dehiscence and no PJI.

CONCLUSION

The rate of RPIO was 0.6%. The current findings suggest that if ICSI is performed under sterile conditions, the risk for septic arthritis or PJI following THA, even in patients with multiple ICSI or ICSI within 3 months prior to surgery, is minimal.

At the Edge of Orthopaedics: Initial Experience with Transarterial Periarticular Embolization for Knee Osteoarthritis in a Romanian Population

BACKGROUND

Transarterial embolization (TAE) of genicular artery branches is a relatively new technique that has emerged as a promising method for delaying invasive knee surgery in patients suffering from degenerative knee osteoarthritis (OA). In mild to moderate OA, invasive major surgery can be safely postponed, and patients with major risk factors now have an alternative. Our aim was to examine the impact of TAE on clinical outcomes in individuals with degenerative knee OA over a 12-month period.

METHODS

A case series of 17 patients diagnosed with knee OA and treated with TAE was included in the study. Every patient was clinically evaluated at different timeframes according to the Western Ontario and McMaster Universities' arthritis index, knee injury, and osteoarthritis outcome scores, and the 36-item short-form survey (WOMAC, KOOS, and SF-36).

RESULTS

At the first follow-up (1 month), KOOS and WOMAC improved from 46.6 ± 13.2 (range 27.3-78.2) to 56.5 ± 13.9 (range 32.3-78.4; p = 0.023) and 49.5 ± 13.2 (range 29.3-82.3) to 59.8 ± 12.6 (range 39.3-83.5, p = 0.018), respectively. Physical SF-36 improved significantly from 42.1 ± 7.75 (range 30.3-57.3) to 50.5 ± 9.9 (range 35.6-67.9; p = 0.032). No significant changes in scores were observed at three, six, or twelve months after TAE.

CONCLUSIONS

TAE provided early pain reduction and considerable improvement in quality of life without complications for a consecutive sample of Romanian patients with mild to severe knee OA.

Septic Arthritis With Superimposed Acute Gouty Arthritis in a Rheumatoid Arthritis Patient

Septic arthritis is a rare but serious complication of both rheumatoid and gouty arthritis and can lead to significant morbidity and even mortality. Here, we report a case of septic arthritis with bacteremia, monosodium urate crystals, and hyperuricemia in a 75-year-old male with long-standing rheumatoid arthritis. Arthrocentesis revealed gram-positive cocci representing group B streptococcus (Streptococcus agalactiae) infection and monosodium urate crystals. A diagnosis of septic arthritis with superimposed acute gouty arthritis was made and the patient was treated accordingly. Management included surgical irrigation and debridement, antibiotic therapy, and systemic glucocorticoids which resulted in a significant improvement in the patient’s clinical status.

A Safe Interval between Preoperative Intra-articular Corticosteroid Injections and Subsequent Knee Arthroscopy

The purpose of this study is to evaluate the influence of intra-articular corticosteroid injections prior to knee arthroscopy on the rate of postoperative infection and define a safe timing interval between intra-articular corticosteroid injections and subsequent knee arthroscopy. The PearlDiver Database was used to identify patients who underwent a knee arthroscopy from 2007 to 2017. Patients were sorted into an injection cohort if they received any intra-articular corticosteroid injections within 6 months before surgery and a control cohort if they received no such injections. The injection cohort was then stratified into subgroups based on the timing of the most recent injection. We identified two types of postoperative infection in the 6 months following surgery: a broad definition of infection using knee infection diagnoses, and a narrow definition of infection requiring surgical treatment. The effects of the timing of preoperative corticosteroid injections on the rates of postoperative infection were investigated. The rate of broadly defined postoperative infection was significantly higher in the 0 to 2 weeks injection group (6.90%, 20/290) than the control group (2.01%, 1,449/72,089, p < 0.001; odds ratio [OR]:3.61 [95% confidence interval [CI]: 2.29, 5.70]). We observed a significant difference regarding the rate of narrowly defined postoperative infection requiring surgical treatment between the 0 and 2 weeks injection group (1.38%, 4/290) and the control group (0.27%, 192/72,089, p < 0.001, OR:5.24 [95% CI: 1.94, 14.21]). No significant differences were observed between other subgroups and the control group in both types of postoperative infection. Intra-articular corticosteroid injections within 2 weeks of knee arthroscopy were statistically significantly associated with higher rates of postoperative infection. This is a Level III, retrospective comparative study.

Septic Arthritis Masquerading as a Flare of Rheumatoid Arthritis: A Not So Straightforward Diagnosis

A typical presentation of septic arthritis (SA) includes pain, swelling, and erythema in the affected joint. Often, patients complain of inability to bear weight on the affected limb. However, some patients may present with subtle symptoms of pain and no fever or obvious swelling of the affected limb thus making the initial suspicion of SA low. Especially, patients with rheumatoid arthritis (RA) may present with polyarticular joint pain and initial synovial fluid analysis from an infected joint not consistent with overt septic arthritis. In such situations, the diagnosis of septic arthritis could be missed on delayed. In this case report, we present a 79-year-old female with a history of RA who presents with polyarticular pain, most notably in her right knee. SA was not initially suspected because of her history of RA and her current presentation with polyarticular pain. The initial synovial analysis did not suggest SA as well. However, cultures of synovial fluid from her right knee confirmed SA. Thus, we have highlighted that physicians should have a high suspicion for SA when addressing joint pain in RA patients.

Streptococcus gordonii septic arthritis of the glenohumeral joint following deltoid intramuscular vaccination

A 68-year-old woman presented for left shoulder pain, decreased range of motion (ROM) and fever 7 days following COVID-19 vaccination. Investigations showed a tender left deltoid mass, decreased shoulder ROM and elevated inflammatory markers. MRI demonstrated a large glenohumeral effusion with synovitis, and arthrocentesis confirmed septic arthritis (SA). She required subtotal bursectomy. Intraoperative joint cultures grew Streptococcus gordonii She completed 6 weeks of antibiotics and is undergoing physical therapy for post-infectious adhesive capsulitis. SA is most commonly due to Staphylococcus aureus and β-haemolytic streptococci, and rarely due to viridans group streptococci including S. gordonii To avoid inadvertent injection into the glenohumeral joint, vaccination should be performed posteriorly and inferiorly into the deltoid musculature. Progressive pain, fever or decreased passive ROM following vaccination should raise concern for SA. Given its rarity, however, concern for secondary SA should not affect the general population's consideration for vaccination.

Critical appraisal of intra-articular glucocorticoid injections for symptomatic osteoarthritis of the knee

OBJECTIVE

Intra-articular (IA) injections of glucocorticoids (GCs) have been shown to decrease pain, increase mobility, and improve quality of life in patients with osteoarthritis (OA) of the knee. Concerns about cartilage loss with IA GCs have prompted reconsideration of their use in knee OA. This review has three objectives: 1) critically review the clinical, molecular, and structural effects of IA GCs in knee OA; 2) provide a design for a clinical trial aimed at improving our understanding of the long-term consequences of IA GCs; and 3) provide practical guidance on the use of IA GCs in patients with knee OA based on current information.

DESIGN

A narrative review of current literature on the use of IA GCs for OA of the knee.

RESULTS

Important questions remain to be fully answered with respect to IA GCs, including long-term effects on all aspects of the structural and molecular environment of the knee, and identification of factors that can reliably predict a positive or negative response to IA GCs.

CONCLUSIONS

While awaiting results from an appropriately designed study, several provisional statements regarding IA GCs can be put forward: 1) IA GCs appear to be a relatively safe option that is effective in specific patients with symptomatic knee OA; 2) there is no definitive evidence that IA GCs accelerate joint deterioration to an important extent or hastens the requirement for knee replacement; and 3) there are few contraindications to IA GCs and injection-associated complications are rare when IA GCs are delivered with proper technique.

Differential characteristics and management of pseudoseptic arthritis following hyaluronic acid injection is a rare complication: a systematic review

IMPORTANCE

Acute pseudoseptic arthritis is a rare complication of hyaluronic acid (HA) injections that is not well documented in the literature. Practitioners initially suspect the symptoms of this complication to represent septic arthritis, cautiously prescribing antibiotics. This review identifies that time to presentation of symptoms postinjection, negative cell cultures and lack of crystallisation could be used as differentials to suspect pseudoseptic arthritis and to prescribe anti-inflammatory drugs while closely monitoring change of symptoms.

OBJECTIVE

The purpose of this study was to describe the presentation, diagnosis and treatment of pseudoseptic arthritis.

EVIDENCE REVIEW

A systematic review of the literature was conducted for studies reporting the use of HA injections for osteoarthritis resulting in pseudoseptic arthritis using the electronic databases MEDLINE, Embase and PubMed. Pertinent data were abstracted from the search yield. A unique case of a pseudoseptic reaction is also presented.

FINDINGS

A total of 11 studies (28 cases), all of level IV and V evidence were included in this review. Reported cases of pseudoseptic arthritis in the literature present with severe joint pain (100%), effusion (100%), inability to weight-bear, functional impairment, and occasionally fever (22.2%). C reactive protein and erythrocyte sedimentation rate are generally elevated (71.4% and 85.7%, respectively), and leucocytosis above 10 000 was less common (50%). All reported cases in the literature identified aseptic growth on arthrocentesis, despite four cases (15.4%) reporting synovial leucocyte counts above 50 000. The presented case is the highest reported leucocyte count at 1 74 960 cells/mm³.

CONCLUSIONS AND RELEVANCE

Acute pseudoseptic arthritis is rare, but a number of cases have been reported in the literature. A high degree of suspicion for pseudoseptic arthritis may be maintained in patients who present under 72 hours following HA injection. Initial antibiotic treatment, along with anti-inflammatory medications until cultures are confirmed to be negative at 5 days, is a cautious approach. However, the strength of this conclusion is limited by the few reported cases. Ultimately, this review is intended to inform practitioners of the symptoms, diagnosis and treatment of this complication, such that it could be safely differentiated from septic arthritis.

LEVEL OF EVIDENCE

IV.

"Old Drugs, New Tricks" - Local controlled drug release systems for treatment of degenerative joint disease

Osteoarthritis (OA) and chronic low back pain (CLBP) caused by intervertebral disc (IVD) degeneration are joint diseases that have become major causes for loss of quality of life worldwide. Despite the unmet need, effective treatments other than invasive, and often ineffective, surgery are lacking. Systemic administration of drugs entails suboptimal local drug exposure in the articular joint and IVD. This review provides an overview of the potency of biomaterial-based drug delivery systems as novel treatment modality, with a focus on the biological effects of drug release systems that have reached translation at the level of in vivo models and relevant ex vivo models. These studies have shown encouraging results of biomaterial-based local delivery of several types of drugs, mostly inhibitors of inflammatory cytokines or other degenerative factors. Prevention of inflammation and degeneration and pain relief was achieved, although mainly in small animal models, with interventions applied at an early disease stage. Less convincing data were obtained with the delivery of regenerative factors. Multidisciplinary efforts towards tackling the discord between in vitro and in vivo release, combined with adaptations in the regulatory landscape may be needed to enhance safe and expeditious introduction of more and more effective controlled release-based treatments with the OA and CLBP patients.

Autologous Protein Solution Injections for the Treatment of Knee Osteoarthritis: 3-Year Results

BACKGROUND

Blood derivative injections have been recently proposed to address osteoarthritis (OA) with overall positive results, although long-term data on their efficacy are lacking. A novel blood derivative has been developed to concentrate growth factors and antagonists of inflammatory cytokines and shown promising early findings.

PURPOSE

To investigate if the positive effects of a single intra-articular injection of autologous protein solution (APS) in patients affected by knee OA-previously documented at 1 year in a multicenter double-blind randomized saline-controlled trial-last up to 3 years.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 46 patients with Kellgren-Lawrence 2 or 3 knee OA were randomized into 2 groups: 1 ultrasound-guided APS injection (n = 31) or 1 saline injection (n = 15). At 1 year, the saline group was allowed to cross over. Patients were re-evaluated at 24 and 36 months through the visual analog scale for pain (VAS), Western Ontario and McMaster Universities Osteoarthritis Index Likert 3.1 (WOMAC LK 3.1), Knee injury and Osteoarthritis Outcome Score (KOOS), 36-Item Short Form Health Survey (SF-36), and Outcome Measures in Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) responder rate. Magnetic resonance imaging evaluation was performed with the MRI Osteoarthritis Knee Score (MOAKS) before and at 24 months after treatment, and radiographs were assessed per Kellgren-Lawrence before and annually after treatment.

RESULTS

In the APS cohort, WOMAC pain improved from 11.5 ± 2.4 (mean ± SD) to 4.3 ± 4.0 at 1 year and to 5.7 ± 5.0 at 3 years (P < .0001 vs baseline). The APS cohort also showed a statistically significant improvement in its KOOS pain score from 39.4 ± 13.1 to 70.6 ± 21.5 at 1 year and to 64.1 ± 24.6 at 3 years (P < .0001 vs baseline) and VAS pain scores from 5.5 ± 2.2 to 2.6 ± 2.5 at 1 year and to 3.4 ± 2.9 at 3 years (P = .0184 vs baseline). VAS pain score significantly worsened from 12 to 36 months (P = .0411). All patients in the saline group decided to cross over to APS, and their final scores were better than baseline, although not significantly better than at the crossover point. Overall, 7 of 26 (26.9%) APS cases and 4 of 14 (28.6%) crossover cases were considered failures as patients underwent further injective treatments or surgical procedures between the 12- and 36-month follow-up. MOAKS findings showed no statistically significant differences. Patients with better cartilage had greater WOMAC pain improvement when their baseline scores were worse, whereas the trend was reversed for patients with cartilage loss at baseline.

CONCLUSION

Intra-articular use of APS for mild to moderate knee OA was safe, and significant pain improvement was documented 3 years after a single injection. Patients with better cartilage status seem to respond better than patients with more cartilage loss, with more clinical improvement even when starting from more painful conditions.

REGISTRATION

NCT02138890 (ClinicalTrials.gov identifier).

Retrospective Comparative Analysis of Opioid Use and Intra-Articular Corticosteroid Injections Before and After Initial Treatment of Knee Osteoarthritis with Hylan G-F 20

Background

Knee osteoarthritis (OA) is a painful condition affecting >250 million people worldwide and is a leading cause of disability. Intra-articular (IA) corticosteroids and/or oral opioids are often recommended for the management of knee OA pain. There are, however, concerns regarding their safety and tolerability.

Study Question

Do patients diagnosed with knee OA show a decrease in opioids or IA corticosteroid injections prescribed/administered in hospitals following hylan G-F 20 treatment?

Study Design

This case-crossover, retrospective study using Health Facts^®, a de-identified electronic health records database, enrolled patients ≥18 years with knee OA treated with hylan G-F 20 between January 1, 2000 and March 31, 2016, with data within 6 months before/after treatment.

Measures and Outcomes

Primary endpoints compared days on opioids, amounts of opioids, and number of IA corticosteroid injections before/after hylan G-F 20 treatment via paired t-tests.

Results

A total of 513 patients were qualified for analysis. In the opioid cohort, the average total number of days on opioids (N = 50; 5.0 vs 13.5 days; P = 0.007) and average total amount of opioids (N = 44; 165.4 morphine mg equivalents [MME] vs 493.7 MME; P = 0.013) were lower 6 months after hylan G-F 20 treatment than 6 months before treatment. In the IA corticosteroid cohort, the average number of IA corticosteroid injections decreased after hylan G-F 20 treatment (N = 36; 0.56 in the 6-month follow-up vs 1.39 before treatment; P < 0.0001). Additional time frames of 1–5 months before and after treatment were examined; similar conclusions were drawn for patients with >2 months of data.

Conclusion

Patients with knee OA previously treated with opioids or IA corticosteroid injections who received hylan G-F 20 demonstrated statistically significant decreases in these medications >2 months following hylan G-F 20 treatment versus >2 months before treatment.

Intra-articular Corticosteroid Injections for Symptomatic Knee Osteoarthritis: What the Orthopaedic Provider Needs to Know

Intra-articular corticosteroid injections have been used for decades in the management of symptomatic osteoarthritis of the knee and remain a common practice. The pain relief from a steroid injection is thought to work by reducing inflammation within the arthritic knee. Substantial variability remains among providers with regard to the technique used to perform the procedure, including the site of the injection, the medications injected, and the level of sterility. The success of steroid injections in relieving arthritic knee pain most often occurs in the short term. However, the efficacy of intra-articular corticosteroid injections varies within the published literature. The latest American Academy of Orthopaedic Surgeons clinical practice guideline does not support conclusive recommendations about the use of intra-articular corticosteroid injections for symptomatic knee osteoarthritis. Providers should be aware of the adverse effects and potential complications of these injections when using them in clinical practice.

Effects of losartan and atorvastatin on the development of early posttraumatic joint stiffness in a rat model

BACKGROUND

After a trauma, exuberant tissue healing with fibrosis of the joint capsule can lead to posttraumatic joint stiffness (PTJS). Losartan and atorvastatin have both shown their antifibrotic effects in different organ systems.

OBJECTIVE

The purpose of this study was the evaluation of the influence of losartan and atorvastatin on the early development of joint contracture. In addition to joint angles, the change in myofibroblast numbers and the distribution of bone sialoprotein (BSP) were assessed.

STUDY DESIGN AND METHODS

In this randomized and blinded experimental study with 24 rats, losartan and atorvastatin were compared to a placebo. After an initial joint injury, rat knees were immobilized with a Kirschner wire. Rats received either losartan, atorvastatin or a placebo orally daily. After 14 days, joint angle measurements and histological assessments were performed.

RESULTS

Losartan increased the length of the inferior joint capsule. Joint angle and other capsule length measurements did not reveal significant differences between both drugs and the placebo. At cellular level both losartan and atorvastatin reduced the total number of myofibroblasts (losartan: 191±77, atorvastatin: 98±58, placebo: 319±113 per counting field, p<0.01) and the percentage area of myofibroblasts (losartan: 2.8±1.8% [p<0.05], atorvastatin: 2.5±1.7% [p<0.01], vs control [6.4±4%], respectively). BSP was detectable in equivalent amounts in the joint capsules of all groups with only a trend toward a reduction of the BSP-stained area by atorvastatin.

CONCLUSION

Both atorvastatin and losartan reduced the number of myofibroblasts in the posterior knee joint capsule of rat knees 2 weeks after trauma and losartan increased the length of the inferior joint capsule. However, these changes at the cellular level did not translate an increase in range of motion of the rats´ knee joints during early contracture development.

Retrospective Analysis of Septic Arthritis Caused by Intra-Articular Viscosupplementation and Steroid Injections in a Single Outpatient Center

Background

Septic arthritis is defined by the presence of pathogen(s) in a joint by direct inoculation or hematogenous spread. Most common organisms include Staphylococcus aureus and Escherichia coli. Clinical presentation is fever, warmth and night pain, with most common joints involved being the knee and hip. Iatrogenic septic arthritis is an uncommon complication of intra-articular injection for osteoarthritis yet its complications can be devastating. We aim to highlight ten cases of iatrogenic septic arthritis in retrospective study reviewing symptoms, signs, laboratory data, causing organisms and reasons leading to those infections.

Methods

Retrospective analysis of charts of ten patients who were admitted to Jersey Shore University Medical Center with diagnosis of iatrogenic septic arthritis.

Results

Average age of patients is 69.9 years. Most common comorbidities seen in our patient were hypertension and diabetes mellitus. The most common intra-articular agents that were injected were cortisone and Synvisc. The mean incubation period was 11.9 days. Most common presenting symptoms were joint pain and swelling. The most common organism isolated in cultures was Streptococcus mitis. A total of 100% of patients underwent surgical intervention for septic arthritis. One case was complicated by sepsis.

Conclusions

Iatrogenic septic arthritis is not common; however its complications can be catastrophic to patients. Improper sterile techniques and untrained physicians are the main risks factors for this complication. Physicians should take proper sterile measures to avoid complications of intra-articular injections.

Cytotoxicity of drugs injected into joints in orthopaedics

Objectives

Intra-articular injections of local anaesthetics (LA), glucocorticoids (GC), or hyaluronic acid (HA) are used to treat osteoarthritis (OA). Contrast agents (CA) are needed to prove successful intra-articular injection or aspiration, or to visualize articular structures dynamically during fluoroscopy. Tranexamic acid (TA) is used to control haemostasis and prevent excessive intra-articular bleeding. Despite their common usage, little is known about the cytotoxicity of common drugs injected into joints. Thus, the aim of our study was to investigate the effects of LA, GC, HA, CA, and TA on the viability of primary human chondrocytes and tenocytes in vitro.

Methods

Human chondrocytes and tenocytes were cultured in a medium with three different drug dilutions (1:2; 1:10; 1:100). The following drugs were used to investigate cytotoxicity: lidocaine hydrochloride 1%; bupivacaine 0.5%; triamcinolone acetonide; dexamethasone 21-palmitate; TA; iodine contrast media; HA; and distilled water. Normal saline served as a control. After an incubation period of 24 hours, cell numbers and morphology were assessed.

Results

Using LA or GC, especially triamcinolone acetonide, a dilution of 1:100 resulted in only a moderate reduction of viability, while a dilution of 1:10 showed significantly fewer cell counts. TA and CA reduced viability significantly at a dilution of 1:2. Higher dilutions did not affect viability. Notably, HA showed no effects of cytotoxicity in all drug dilutions.

Conclusion

The toxicity of common intra-articular injectable drugs, assessed by cell viability, is mainly dependent on the dilution of the drug being tested. LA are particularly toxic, whereas HA did not affect cell viability.

Cite this article: P. Busse, C. Vater, M. Stiehler, J. Nowotny, P. Kasten, H. Bretschneider, S. B. Goodman, M. Gelinsky, S. Zwingenberger. Cytotoxicity of drugs injected into joints in orthopaedics. Bone Joint Res 2019;8:41–48. DOI: 10.1302/2046-3758.82.BJR-2018-0099.R1.

Platelet-Rich Plasma Versus Hyaluronic Acid Injections for the Treatment of Knee Osteoarthritis: Results at 5 Years of a Double-Blind, Randomized Controlled Trial

BACKGROUND

Platelet-rich plasma (PRP) injections have been proposed as a new conservative option for knee degeneration to provide symptomatic relief and delay surgical intervention. Although the current literature provides some evidence on the benefits of this technique compared with viscosupplementation, no studies have been performed to compare their long-term effects.

PURPOSE

To compare the long-term clinical outcomes provided by intra-articular injections of either PRP or hyaluronic acid (HA) to treat knee degenerative disease.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients with a history of chronic symptomatic knee degenerative changes and osteoarthritis (Kellgren-Lawrence grade 0-3) were enrolled: 192 patients were randomized to undergo 3 blinded weekly intra-articular injections of either PRP or HA. Patients were prospectively evaluated before the injection and then at 2, 6, 12, and 24 months and a mean of 64.3 months (SD, 7.8 months) of follow-up. Evaluation was based on International Knee Documentation Committee (IKDC) subjective (main outcome), EuroQol visual analog scale, and Tegner scores; 167 patients reached the final evaluation.

RESULTS

Both treatments were effective in improving knee functional status and symptoms over time: Mean ± SD IKDC subjective score improved significantly for both PRP and HA groups ( P < .0005) and remained stable over time up to 24 months (from 53.3 ± 14.3 to 67.3 ± 18.1 and from 50.3 ± 13.2 to 62.1 ± 20.8 for PRP and HA groups, respectively). At final evaluation, a significant IKDC reduction was observed in both treatment groups, with the PRP group still presenting significantly higher values compared with baseline: PRP 60.5 ± 19.0 ( P < .001 vs baseline), HA 55.7 ± 18.8 (not significant vs baseline). A comparative analysis showed no significant intergroup difference in any of the clinical scores at any follow-up point. The median duration of patient subjective perception of symptomatic relief was 9 months for HA and 12 months for PRP (not significant). The only significant difference was observed in the rate of reintervention at 24 months, which was significantly lower in the PRP group (22.6% vs 37.1%, P = .036).

CONCLUSION

Both treatments were effective in improving knee functional status and symptoms over time. PRP did not provide an overall superior clinical improvement compared with HA in terms of either symptomatic-functional improvement at different follow-up points or effect duration.

REGISTRATION

NCT01670578 (ClinicalTrials.gov identifier).

Corticosteroids and Hyaluronic Acid Injections

Osteoarthritis is a common condition that affects many individuals resulting in pain, reduced mobility, and decreased function. Corticosteroids have been a mainstay of osteoarthritis treatment. Studies have shown that they provide short-term pain improvement and can be used for osteoarthritis flares. Hyaluronic acid injections have extensively been studied in knee osteoarthritis but to a lesser degree in other joints. Despite some debate between societies, a large number of recent studies have shown hyaluronic acid to be a viable treatment option showing longer-term improvement in both pain and function.

Preoperatively elevated serum inflammatory markers increase the risk of periprosthetic joint infection following total knee arthroplasty in patients with osteoarthritis

Background

The purpose of this study was to evaluate the prevalence of preoperatively elevated serum inflammatory markers and to determine its association with periprosthetic joint infection (PJI) in patients with osteoarthritis (OA) undergoing total knee arthroplasty (TKA).

Methods

From January 2010 to May 2014, we retrospectively reviewed 3,376 consecutive patients who were scheduled for unilateral TKA due to OA. Patients with inflammatory arthritis, posttraumatic arthritis, previous knee surgery, simultaneous surgery or arthroplasty, and comorbidity with autoimmune disease, hepatitis, renal disease, respiratory tract infections, urinary tract infection, and malignancy were excluded. One hundred and forty patients with preoperatively elevated erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) were enrolled. The control group was matched by age, sex, body mass index, and year of index surgery in 1:1 ratio. All patients were followed for a minimum of 1 year or until the occurrence of PJI. PJI was defined based on the criteria in the International Consensus Meeting. A multivariate Cox proportional hazards model was utilized to calculate the HR and 95% CI.

Results

The prevalence of preoperatively elevated inflammatory markers was 4.1%. The rate of PJI was significantly higher in the both elevated ESR and CRP groups (12.5%, 4/32) compared with both normal group (1.4%, 2/140) and either high group (0.9%, 1/108) (P<0.001). Patients with preoperative elevated ESR and CRP had a significant risk of PJI compared to those with normal serum inflammatory markers (HR: 15.8, 95% CI: 2.57–96.7, P=0.003) after adjusting confounding factors. The cumulative rate for PJI was 6.3% (95% CI: 0%–14.27%) at 1 year and 16.5% (95% CI: 0%–30.66%) at 5 years for both high ESR and CRP groups, which was significantly higher than other 2 groups (P=0.0002).

Conclusion

Although the prevalence of preoperatively elevated ESR and CRP is low, routine examination of ESR and CRP preoperatively might be necessary to prevent subsequent PJI in patients with OA following TKA.