Late hemorrhagic pseudoseptic arthritis encountered during total knee arthroplasty due to hyaluronic acid viscosupplementation

Transfer RNAs-derived small RNAs and their application potential in multiple diseases

The role of tRNAs is best known as adapter components of translational machinery. According to the central dogma of molecular biology, DNA is transcribed to RNA and in turn is translated into proteins, in which tRNA outstands by its role of the cellular courier. Recent studies have led to the revision of the canonical function of transfer RNAs (tRNAs), which indicates that tRNAs also serve as a source for short non-coding RNAs called tRNA-derived small RNAs (tsRNAs). tsRNAs play key roles in cellular processes by modulating complicated regulatory networks beyond translation and are widely involved in multiple diseases. Herein, the biogenesis and classification of tsRNAs were firstly clarified. tsRNAs are generated from pre-tRNAs or mature tRNAs and are classified into tRNA-derived fragments (tRFs) and tRNA halves (tiRNA). The tRFs include five types according to the incision loci: tRF-1, tRF-2, tRF-3, tRF-5 and i-tRF which contain 3′ tiRNA and 5′ tiRNA. The functions of tsRNAs and their regulation mechanisms involved in disease processes are systematically summarized as well. The mechanisms can elaborate on the specific regulation of tsRNAs. In conclusion, the current research suggests that tsRNAs are promising targets for modulating pathological processes, such as breast cancer, ischemic stroke, respiratory syncytial virus, osteoporosis and so on, and maintain vital clinical implications in diagnosis and therapeutics of various diseases.

Hyaluronic Acid Injections for Knee Osteoarthritis: Has Utilization Among Medicare Beneficiaries Changed Between 2012 and 2018?

BACKGROUND

The utilization of hyaluronic acid (HA) for the management of knee osteoarthritis (OA) remains controversial, and more information is needed regarding how its utilization and financial burden have changed over recent years. The purpose of our analysis was to evaluate changes in overall utilization and health-care costs associated with HA injections among Medicare beneficiaries over a contemporary time frame.

METHODS

The 2012 to 2018 Medicare Fee-for-Service Provider Utilization and Payment Public Use Files (PUFs) were utilized for our analysis. Organized by Healthcare Common Procedure Coding System (HCPCS) codes, these files capture 100% of Medicare Part B claims. Payment and utilization data were collected for all HCPCS codes corresponding to injection of an HA formulation. The number of services involving HA as well as the total cost of HA administration in 2020 U.S. dollars were tabulated. Mann-Kendall trend tests were used to evaluate trends in utilization for providers nationally and when segregated by specialty.

RESULTS

Total HA utilization increased significantly from 2012 (n = 1,090,503) through 2018 (n = 1,209,489; p = 0.04). Although orthopaedic surgeons did not demonstrate significant changes in total utilization rates (p = 0.23), the average number of services per orthopaedic surgeon increased significantly (p = 0.02). Reflecting a substantial growth in the number of advanced practice providers (APPs) providing injections, there was a significant increase in utilization and associated costs among physician assistants (p < 0.01) and nurse practitioners (p < 0.01). Total costs associated with HA services increased significantly from $290.10 million to $325.02 million (p < 0.01).

CONCLUSIONS

Despite the 2013 American Academy of Orthopaedic Surgeons clinical practice guideline recommending against the clinical utility of these injections, HA services continued to be widely implemented among Medicare beneficiaries. Although there were variations across specialties when evaluating overall utilization rates as well as rates per provider, APPs largely contributed to the increase seen in the U.S. over this study period. More data are needed to support continued implementation and spending on this low-value care.

Acute pseudogout presenting as an exception to Musculoskeletal Infection Society criteria in total knee arthroplasty: a case report

In this case, a 78-year-old female with no previous medical history of crystalline arthropathy presented with pain, effusion, and erythema about a total knee arthroplasty (TKA) performed 13 years prior. Implementation of a novel synovial fluid alpha-defensin assay ruled out periprosthetic joint infection (PJI) despite a positive 2018 Musculoskeletal Infection Society (MSIS) minor criteria score of 8 points, a significant diagnostic differentiation which prevented secondary invasive debridement or joint irrigation intervention. Confirmatory histologic study was positive for calcium pyrophosphate crystals, indicative of acute pseudogout inflammation rather than PJI or septic arthritis manifestation. The patient was then conservatively managed medically for a pseudogout flare and had no evidence of infection with normal physical exam and laboratory study at one- and two-years post treatment, respectively. Given the predominantly clinical nature of current PJI assessment in-clinic coupled with notable risks associated with aggressive re-intervention in the setting of suspected infection, critical need exists for the maturation of sensitive, reliable empiric measures which may assist in guiding orthopaedic surgeon evaluation of patients presenting with inflammatory symptomology around a previous surgical site. In this case, we conclude that patients with a negative alpha-defensin assay alongside crystalline arthropathy on histology may be cautiously yet successfully treated non-operatively despite clinical MSIS criteria concerning for PJI.