Most Publications Regarding Platelet-Rich Plasma Use in the Knee Are From Asia, Investigate Injection for Osteoarthritis, and Show Outcome Improvement: A Scoping Review

PURPOSE

To evaluate and synthesize the available literature related to platelet-rich plasma (PRP) treatment of knee pathologies and to provide recommendations to inform future research in the field.

METHODS

PubMed, CINAHL, and Scopus databases were queried on October 6, 2023. All identified citations were collated and uploaded into Covidence for screening and data extraction. Studies were included if they were human studies published in English with adult cohorts that received PRP as a procedural injection or surgical augmentation for knee pathologies with patient-reported outcome measures (PROMs) and level of evidence Levels I-IV.

RESULTS

Our search yielded 2,615 studies, of which 155 studies from 2006 to 2023 met the inclusion criteria. Median follow-up was 9 months (±11.2 months). Most studies (75.5%) characterized the leukocyte content of PRP, although most studies (86%) did not use a comprehensive classification scheme. In addition, most studies were from Asia (50%) and Europe (32%) and were from a single center (96%). In terms of treatment, 74% of studies examined PRP as a procedural injection, whereas 26% examined PRP as an augmentation. Most studies (68%) examined treatment of knee osteoarthritis. Many studies (83%) documented significant improvements in PROMs, including 93% of Level III/IV evidence studies and 72% of Level I/II evidence studies, although most studies (70%) failed to include minimal clinically important difference values. The visual analog scale was the most-used PROM (58% of studies), whereas the Short Form Health Survey 36-item was the least-used PROM (5% of studies).

CONCLUSIONS

Most published investigations of knee PRP are performed in Asia, investigate procedural injection for osteoarthritis, and show significant outcome improvements. In addition, this review highlights the need for better classification of PRP formulations.

LEVEL OF EVIDENCE

Level IV, scoping Review of level I-IV studies.

Intraoperative Performance with the Exoscope in Spine Surgery: An Institutional Experience

BACKGROUND

Exoscope use in spinal neurosurgery has become a promising surgical option providing enhanced operative field visibility and ergonomics. However, data on its use in spine surgery are underreported in the literature. We aimed to assess the intraoperative outcomes in exoscope-assisted spine surgery compared with similar procedures performed using the operative microscope.

METHODS

A retrospective review was performed of all spinal surgeries performed using an exoscope and, subsequently, an equal number of operative microscope cases performed by 2 senior surgeons at a single institution from 2016 to 2023. The variables included demographics, clinical presentation, surgical treatment, and operative outcomes.

RESULTS

A total of 123 exoscope spinal surgeries were performed on 116 unique patients with a mean age of 67 ± 14 years, of whom 60 (52%) were women. The microscope group included 126 surgeries on 120 unique patients with a mean age of 62 ± 14 years, of whom 53 (45%) were women. The mean blood loss (28 mL vs. 132 mL; P = 0.0009), operative time (83 minutes vs. 103 minutes; P = 0.006), and length of stay (1.04 days vs. 1.73 days; P = 0.02) were significantly less for the exoscope group than for the microscope group.

CONCLUSIONS

The use of the exoscope resulted in a shorter operative time, less blood loss, a shorter length of stay, and favorable clinical outcomes compared with the use of the operative microscope. Neurosurgeons should consider this seemingly efficacious and ergonomically favorable visual technology for spinal surgeries.

Characterization and Performance of Carbon Films Deposited by Plasma and Ion Beam Based Techniques

Plasma and ion beam based techniques have been used to deposit carbon-based films. The ion beam based method, a cathodic arc process, used a magnetically mass analyzed beam and is inherently a line-of-sight process. Two hydrocarbon plasma-based, non-line-of-sight techniques were also used and have the advantage of being capable of coating complicated geometries. The self-bias technique can produce hard carbon films, but is dependent on rf power and the surface area of the target. The pulsed-bias technique can also produce hard carbon films but has the additional advantage of being independent of rf power and target surface area. Tribological results indicated the coefficient of friction is nearly the same for carbon films from each deposition process, but the wear rate of the cathodic arc film was five times less than for the self-bias or pulsed-bias films. Although the cathodic arc film was the hardest, contained the highest fraction of sp3 bonds and exhibited the lowest wear rate, the cathodic arc film also produced the highest wear on the 440C stainless steel counterface during tribological testing. Thus, for tribological applications requiring low wear rates for both counterfaces, coating one surface with a very hard, wear resistant film may detrimentally affect the tribological behavior of the counterface.

Emerging concepts in antihypertensive therapy: the benefits of angiotensin II blockade

Essential hypertension affects more than 40 million Americans, or one in four adults. The prevalence of hypertension is greater among the African-American population, with a distressingly high rate of end-organ complications. Although diabetes mellitus has surpassed hyper tension as the dominant etiology of end-stage renal disease in the United States, kidney failure secondary to hypertensive nephrosclerosis remains a significant problem, particularly among African Americans. During the past decade, a shift in the paradigm for the renin-angiotensin system (RAS) has evolved from a circulating vasoactive cascade toward angiotensin II (ANG II) formation at the cellular level. The molecular components of the RAS have been identified in cells, documenting the existence of an autocrine tissue RAS, as well as the presence of enzymes, which catalyze the formation of ANG II by angiotensin-converting-enzyme-independent pathways, providing new targets for therapeutic intervention. The latter challenge has important clinical implications, in view of recent evidence implicating ANG II in pathologic cell growth and cell death and fundamental events in the remodeling of the vascular wall and myocardium in the setting of hypertension. This review focuses on ANG II as a major determinant of end-organ damage in essential hypertension; the benefits of ANG II blockade at the end-organ level, which appear to be independent of the blood pressure-lowering effect; and the emerging role for ANG II receptor antagonists as first-line agents in the treatment of essential hypertension.

A recombinant adenovirus expressing wild type p53 induces apoptosis in drug-resistant human breast cancer cells: a gene therapy approach for drug-resistant cancers

The cytotoxicity of a recombinant adenovirus expressing the wild type tumor suppressor gene p53 (AdWTp53) was studied in two human breast cancer MCF-7 sublines selected for resistance to adriamycin (MCF-Adr) and mitoxantrone (MCF-Mito). Although the levels of wild type p53 protein following infection with AdWTp53 are comparable in all cell lines, the two drug-resistant MCF-7 sublines were 300- and 18-fold more sensitive to killing by AdWTp53 compared with the drug-sensitive parental MCF-7 cell lines. In each cell line, AdWTp53 infection led to cell cycle arrest, and reduction of Cdk2 and cyclin B1-Cdc2 activity. Nucleosomal DNA fragmentation analysis (as a function of apoptosis) following AdWTp53 infection revealed that, while the parental MCF-7 cells failed to undergo apoptosis, both drug-resistant cell lines showed distinct DNA laddering. In MCF-Adr cells, a combination treatment of AdWTp53 and adriamycin was much more toxic than either of the reagents used individually. Finally, exposure of a mixed population of MCF-Adr and CD34+ cells to AdWTp53 selectively prevented MCF-Adr cell colony formation, while there was no inhibition of CFU-GM colony formation from CD34+ cells. These findings suggest that some drug-resistant human breast cancers may be effectively treated with adenovirus expressing wild type p53.