Incidence of Postoperative Infection Following Simultaneous Bilateral Knee Arthroplasty: A Systematic Review and Meta-Analysis

Total knee arthroplasty is one of the most common orthopedic procedures. Simultaneous bilateral knee arthroplasty involves performing total knee arthroplasty on both knees in a single anesthetic session. This systematic review and meta-analysis followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. A primary search was performed using PubMed, EBSCO, Scopus, Web of Science, Clarivate, and Google Scholar databases. Quantitative data synthesis was performed using MedCalc® Statistical Software version 20.115 to determine the pooled prevalence of the infection among patients who underwent simultaneous bilateral knee arthroplasty. The Newcastle-Ottawa Scale was used to assess study quality. We included 30 studies in our quantitative data synthesis, with a total population of 118,502 patients (237,004 knees). The pooled prevalence of superficial infection, deep infection, and unspecified surgical site infection was estimated to be 0.86% (95% confidence interval: 0.62-1.13%), 0.84% (95% confidence interval: 0.64-1.05%), and 1.18% (95% confidence interval: 0.45-2.27%), respectively. There was significant heterogeneity (I2 >50%) in all analyses, and inspection of funnel plots revealed a symmetrical distribution of plotted data. We found that the infection rates following simultaneous bilateral knee arthroplasty were relatively low but heterogeneous, as the data showed marked variability. Superficial infections were more common than deep infections; however, there was a small difference in their prevalence. Furthermore, the reliability of our findings was limited owing to significant heterogeneity.

Cytotoxic effects of different mouthwash solutions on primary human articular chondrocytes and normal human articular cartilage - an in vitro study

OBJECTIVES

To compare the cytotoxicity of octenidine dihydrochloride and chlorhexidine gluconate at different concentrations on primary human articular chondrocytes and cartilage.

MATERIALS AND METHODS

Primary cultures of human normal adult articular chondrocytes were exposed to octenidine dihydrochloride (0.001562%, 0.003125%, 0.00625%, 0.0125%, 0.025%, 0.05%, and 0.1%), chlorhexidine gluconate (0.003125%, 0.00625%, 0.0125%, 0.025%, 0.05%, 0.1%, and 0.2%), and control (Dulbecco's modified Eagle medium or phosphate-buffered saline) for 30 s. Normal human articular cartilage explants were exposed to octenidine dihydrochloride (0.1% versus control) and chlorhexidine gluconate (0.1% versus control) for 30 s. The viability of human articular chondrocytes was measured by Trypan blue staining, Cell Proliferation Reagent WST-1, and Live/Dead staining. The proliferation of human chondrocytes was measured using the Cell Proliferation Reagent WST-1. The viability of human articular cartilage explants was measured by using Live/Dead staining.

RESULTS

Octenidine dihydrochloride and chlorhexidine gluconate exposure decreased cell viability and proliferation in a dose-dependent manner in primary human articular chondrocytes. Octenidine dihydrochloride and chlorhexidine gluconate exposure decreased cell viability in human articular cartilage explant cultures.

CONCLUSION

The degree of toxicity varied between octenidine dihydrochloride and chlorhexidine gluconate, with chlorhexidine gluconate being less toxic than octenidine dihydrochloride at the same concentration. Additionally, both octenidine dihydrochloride and chlorhexidine gluconate evaluation had cytotoxic effects on human articular cartilage. Therefore, dosing for the antimicrobial mouthwash ingredients administration would ideally be determined to remain below IC50.

CLINICAL RELEVANCE

These data support the in vitro safety of antimicrobial mouthwashes on primary adult human articular chondrocytes.

Arthroplasty of a Charcot Knee in a Patient With Congenital Insensitivity to Pain

Hereditary sensory and autonomic neuropathies (HSANs) include hereditary disorders that cause congenital insensitivity to pain. Moreover, patients diagnosed with such disorders are known to have genetic mutations that alter their deep pain sensation, making them more prone to developing bone and joint complications such as repetitive fractures, joint swelling, and Charcot arthropathy. Neuropathic arthropathy (Charcot joint) is a rare and relatively poorly understood condition; it is suggested to be caused by autonomic dysfunction and repetitive microtrauma and characterized by instability and joint destruction. Diagnosing the idiopathic Charcot joint is challenging and is considered to be a diagnosis of exclusion. In addition, there are limited cases of Charcot knees managed by arthroplasty. Patients with Charcot knees are commonly characterized by profound bone loss, diffuse synovitis, and instability in the knee joint. In this article, we report the case of a 13-year-old patient with known NTRK1 gene mutation who presented with recurrent knee joint swelling episodes and instability without pain. She was diagnosed with Charcot knee joint and underwent right hinged total knee replacement. At one-year follow-up, she continued to have good knee stability and an overall functional gait. Our findings suggest that managing Charcot knee joint with total knee replacement in patients with HSAN may show improvement in terms of stability, swelling, and overall gait.

Mixed-Methods Analysis of a Validated Arthroscopic Knot-Tying Simulator With New Indirect Visualization Condition

Background:

Simulation provides low-risk opportunities for surgical trainees to learn and practice fundamental skills. One simulation tool for orthopaedics is the Arthroscopic Knot (ArK) Trainer, which has been validated as an effective simulation tool across multiple methodologies. Previous studies have investigated the ArK Trainer in its basic form using clear plexiglass, which allows direct visualization of tissue anchors.

Purpose:

Using a mixed-methods approach, we assessed and compared junior and senior trainees’ Seoul Medical Center (SMC) knot–tying performance under direct and indirect visualization.

Study Design:

Cross-sectional study.

Methods:

Fourteen orthopaedic surgery postgraduate trainees at a single medical school were recruited to participate. Trainees tied SMC knots using the Ark Trainer under direct and indirect visualization. A mixed-methods approach was used to evaluate knot-tying proficiency and characterize participants’ approach to knot-tying. Knot-tying proficiency was evaluated using validated tools: a task-specific checklist (TSC), a global rating scale (GRS), and a proficiency scale (PS). Participants’ approach to knot-tying was characterized using Likert-type questionnaires and semistructured interviews. An α level of .10 was set a priori owing to the small pool of trainees.

Results:

The 14 participants included 7 junior residents (postgraduate years [PGYs] 1 and 2) and 7 senior residents (PGY ≥3), of whom 3 were fellows (PGY 6). Senior trainees outperformed junior trainees on both versions of the ArK Trainer: clear (GRS, P = .055; PS, P = .075) and covered (TSC, P = .05). Overall, participants performed better under direct visualization conditions (GRS, P = .05). In semistructured interviews, significantly more senior trainees discussed relying on haptic cues while tying knots under direct visualization (P = .021). The majority of trainees agreed that both versions of the ArK Trainer were realistic and appropriate practice formats for their level of training.

Conclusion:

Senior trainees were significantly more experienced than were junior trainees in arthroscopic skill and outperformed them on both configurations: direct (PS and GRS) and indirect (TSC) visualization. Experienced trainees were significantly more likely to report using tactile cues to aid knot-tying under indirect visualization. It is likely that inexperienced trainees rely more heavily on direct visualization and that the use of tactile cues may be an indicator of knot-tying proficiency. Trainees recommended progression from direct to indirect visualization configurations for inexperienced learners.

First insights into chlorhexidine retention in the oral cavity after application of different regimens

Objectives

This in situ study aimed to determine and compare the chlorhexidine (CHX) retention in the oral cavity after the application of different CHX pharmaceutical regimens.

Methods

Five volunteers used different CHX treatment regimens including mouth rinses, dental spray and toothpaste gel. After the application of the different CHX regimens, 2-μl samples were taken from saliva and buccal mucosa pellicle as well as the dental pellicle samples formed on standardized enamel surfaces. Sample collection was conducted at six time points within 12 h. Retention of CHX was measured using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry.

Results

CHX retention values in the oral mucosa pellicle were significantly higher than those in saliva. CHX remained in the mucosal pellicle at microgrammes per millilitre levels for 12 h after mouth rinsing, 10 h after spray application and 2 h after using the toothpaste. CHX was detected in the dental pellicle for at least 12 h after application of mouth rinsing and spray. Retention of CHX after mouth rinsing or spray application was significantly higher than the retention after using toothpaste.

Conclusions

Oral mucosa was the favourable site for CHX retention. Higher mouth rinse concentration and longer rinsing time produced a slight increase in CHX retention. CHX spray provided considerable retention values, whereas toothpaste gel delivered the lowest retention after application. MALDI-TOF was a sensitive method with excellent limits of quantification for CHX detection.

Profiling of cytokines, chemokines and growth factors in saliva and gingival crevicular fluid

In saliva and gingival crevicular fluid (GCF) soluble factors such as cytokines, chemokines and growth factors have shown a great potential serving as biomarkers for early detection and/or diagnosis of oral and systemic diseases. However, GCF and saliva, which one is a better source is still under debate. This study aimed to gain an overview of cytokines, chemokines and growth factors in saliva and GCF to pave the way for selecting suitable oral fluids for oral and systemic diseases. Multiplex cytokine assay was conducted to determine concentrations of cytokines, chemokines and growth factors in saliva and GCF samples from healthy subjects. The protocol for sample collection was carefully optimized. Stabilization, repeatability, and donor variation of the profiles were analyzed. We found that for different donors, cytokine and chemokine profiles showed unique patterns in saliva but similar patterns in GCF. In terms of growth factors, the profiles were individualized in saliva and GCF. All profiles stayed stable for the same healthy individual. In saliva, profiles of cytokines, chemokines and growth factors are individualized for different donors. In GCF, profiles of cytokines and chemokines are similar. Other factors, such as growth factors and T helper-related cytokines, are highly variable in donors. Profiles of soluble factors are not correlated in saliva and GCF. The comprehensive cytokine profiles in saliva and GCF reported in this work would serve as a good base for choosing promising cytokines for developing biomarkers in oral fluids.

Effects of Octenidine on the Formation and Disruption of Dental Biofilms: An Exploratory In Situ Study in Healthy Subjects

Dental biofilms are highly structured, complex multispecies communities that, if left untreated, lead to severe oral complications such as caries and periodontal diseases. Therefore, antibiofilm agents are often recommended for both preventive and therapeutic measures. However, biofilm management can be challenging due to the low sensitivity of biofilms to antimicrobial treatments. Octenidine dihydrochloride (OCT) is a highly effective antibacterial agent. Because the OCT antibiofilm efficacy has not been studied in situ, this exploratory crossover study aimed to evaluate the effects of OCT mouth rinsing on biofilm formation and on the disruption of mature biofilms. Moreover, a comparison to the gold-standard chlorhexidine (CHX) was conducted. The biofilms were formed intraorally by 5 healthy volunteers on enamel specimens fixed to acrylic splints. For biofilm formation analysis, OCT, CHX, or water rinses were applied for 30 s every 12 h. The samples evaluation took place at 24-and 48-h time points. For biofilm disruption analysis, sample assessment was performed before and directly after the first OCT or CHX rinse on 48-h mature biofilms. A second rinse was carried out 12 h later. The last assessment was applied to 72-h mature biofilms. The biofilms were analyzed by fluorescence microscopy and transmission electron microscopy. The results showed OCT significantly reducing biofilm formation and bacterial vitality in situ. Simultaneously, the biofilm thickness was strongly decreased. Moreover, a single application of OCT to a 48-h mature biofilm induced substantial biofilm disruption. In addition, the efficacy of OCT compared favorably to CHX. These findings show that OCT rinses prevent biofilm formation and disrupt preexisting mature biofilms formed by healthy subjects. This work suggests that OCT might be used for dental biofilm management as a part of the medical treatment of oral diseases. Future studies with a larger subject heterogeneity and number are needed to confirm the observed OCT effects.

Determination of chlorhexidine retention in different oral sites using matrix-assisted laser desorption/ionization-time of flight mass spectrometry

OBJECTIVE

The aim of this study was to determine chlorhexidine retention in different oral sites after a one-time 30 s mouth rinsing.

DESIGN

Five volunteers were asked to rinse their mouth with 10 ml of 0.2 % chlorhexidine digluconate for 30 s. After rinsing, samples were collected from the interdental area, buccal dental pellicle, anterior labial and posterior buccal mucosa, and saliva with a microbrush at five-time points within 24 h. Retention of chlorhexidine was measured using matrix-assisted laser desorption/ionization-time of flight mass spectrometry with a quantification limit of 15 ng/ml.

RESULTS

Chlorhexidine remained in the oral cavity at micrograms per milliliter levels for 11 h after mouth rinsing and was even detected 24 h after application. The results showed a distinct decline of intraoral chlorhexidine levels during the first 6 h after rinsing and it was then retained at low concentrations for at least 24 h.

CONCLUSIONS

The dental pellicle and oral mucosa were favorable sites for chlorhexidine retention. The novel method used for chlorhexidine determination offered excellent quantification limits and readily permitted quantification of chlorhexidine.

Postoperative Numbness: A Survey of Patients After Hip Arthroscopic Surgery

Background:

Hip arthroscopic surgery is a rapidly growing procedure that requires distraction of the leg to access the joint. A frequently reported complication of this procedure is postoperative numbness, with rates between 1% and 20% reported in the literature.

Purpose/Hypothesis:

The purpose of this study was to determine the factors contributing to the development and effect of numbness on functional outcomes. We hypothesized that this complication is underreported and that its prevalence is higher than what has been described in the literature.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patients who had undergone hip arthroscopic surgery between 2012 and 2016 were included, and a telephone survey was conducted to collect data. Data related to the procedure and outcome scores were collected via a systematic chart review for the included patients. Data analysis was conducted for means, SDs, frequencies, and percentages. For comparative statistics, t tests and multiple logistic regression models were used.

Results:

A total of 221 patients (113 male, 108 female; mean age, 39.8 ± 13.34 years) completed the survey out of 362 eligible patients. Overall, 37% (n = 82) of patients reported having experienced some form of numbness after surgery. Approximately 43% (35/82) of the patients reported resolution by 6 weeks postoperatively, and 68% (56/82) of numbness was reported to have completely resolved by 6 months. The duration of surgery was a significant factor for the development of postoperative numbness (P = .010; odds ratio, 2.18) when comparing procedures longer than 50 minutes with procedures shorter than 50 minutes (first incision until closure). Postoperative numbness was associated with a negative effect on the International Hip Outcome Tool–33 (iHOT-33) score that reached statistical significance at the 1-year (numbness, 60.19; no numbness, 74.21; P = .006) and 2-year time points (numbness, 52.04; no numbness, 72.69; P = .01).

Conclusion:

This study confirmed our hypothesis that postoperative numbness is more common in our patient population than the incidence reported in the literature. This adverse event was also shown to be associated with decreased postoperative functional outcomes, as measured by the iHOT-33 at 1 and 2 years postoperatively.

Cystic bone tumors of the foot and ankle

Bone tumors are relatively rare in the foot and ankle region. Many of them present as cystic lesions on plain films. Due to the relative rarity of these lesions and the complex anatomy of the foot and ankle region, identification of such lesions is often delayed or they get misdiagnosed and mismanaged. This review discusses the most common cystic tumors of the foot and ankle including their radiographic features and principles of management.

Revision of Failed Rotator Cuff Reconstruction With a Large Humeral Head Cyst

A revision rotator cuff repair is a technically challenging surgical procedure. This can be further complicated by the presence of poor quality of the cuff tissue, as well as a large greater tuberosity cyst, typically located at the rotator cuff footprint. This Technical Note discusses the surgical approach to deal with a revision rotator cuff tear with a large humeral head cyst. This described arthroscopic technique is performed in a single-stage procedure using a human dermal allograft (GraftJacket) for augmentation. This technique was specifically designed to (1) address the limited area for anchor placement, (2) use a bone graft, demineralized bone matrix, for repairing the bone cyst, and (3) optimize the biology for healing by augmenting the reconstruction with GraftJacket.