All Publications

  • Surgeon practice patterns for pre-soaking ACL tendon grafts in vancomycin: a survey of the ACL study group. Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA Xiao, M., Sherman, S. L., Safran, M. R., Abrams, G. D. 2020


    PURPOSE: To survey members of The ACL study group to determine the current practice patterns surrounding the technique of pre-soaking ACL grafts in vancomycin.METHODS: A web-based questionnaire was distributed to members of the ACL Study Group. Questions included the use of vancomycin solution for graft soaking during ACL reconstruction, their protocol for soaking the graft, vancomycin concentration utilized, graft choices, and concerns with the technique.RESULTS: Sixty-six (57%) ACL surgeons completed the survey. Approximately one-third (37.9%) of respondents currently pre-soak their ACL grafts in vancomycin prior to implantation, with 60% of these surgeons being from Europe. Seventy-six percent have adopted this practice within the past 5years. The majority of surgeons wrap the graft in a vancomycin-soaked gauze prior to implantation (56%), soak for a variable amount of time before implantation (56%), use a concentration of 5mg/mL (68%), and soak hamstring grafts (92%). Concerns included the mechanical properties of the graft (35%), cost of vancomycin (23%), availability (12%), and antibiotic resistance (9%).CONCLUSION: This survey demonstrates that 37.9% of ACL study group members currently utilize vancomycin to pre-soak ACL tendon grafts as a means to decrease post-operative infection risk, with the majority of surgeons having implemented this practice within the past 5years. The biggest concern towards using vancomycin was the mechanical properties of the graft after soaking.LEVEL OF EVIDENCE: IV.

    View details for DOI 10.1007/s00167-020-06265-1

    View details for PubMedID 32902684

  • Administrative Databases Utilized for Sports Medicine Research Demonstrate Significant Differences in Underlying Patient Demographics and Resulting Surgical Trends. Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association Xiao, M., Donahue, J., Safran, M. R., Sherman, S. L., Abrams, G. D. 2020


    To discern differences between the PearlDiver and MarketScan databases with regards to patient demographics, costs, re-operations, and complication rates for isolated meniscectomy.We queried the PearlDiver Humana Patient Records Database and the IBM® MarketScan® Commercial Claims and Encounters database for all patients who had record of meniscectomy denoted by CPT-29880 or CPT-29881 codes between January 1, 2007 and December 31, 2016. Those that had any other knee procedure at the same time as the meniscectomy were excluded, and the first instance of isolated meniscectomy was recorded. Patient demographics, Charlson Comorbidity Index (CCI), reoperations, 30- and 90-day complication rates, and costs were collected from both databases. Pearson's ?2 test with Yate's continuity correction and the student t-test were used to compare the two databases, and an alpha value of 0.05 was set as significant.We identified 441,147 patients with isolated meniscectomy from the MarketScan database (0.36% of total database), approximately 10 times the number of patients (n = 49,924; 0.20% of total database) identified from PearlDiver. The PearlDiver population was significantly older (median age: 65-69) than the MarketScan cohort, where all patients were younger than 65 (median age: 52; p < 0.001). Average CCI was significantly lower for MarketScan (0.172, SD: 0.546) compared to PearlDiver (1.43, SD: 2.05; p < 0.001), even when restricting the PearlDiver cohort to patients under 65 (1.02, SD: 1.74; p < 0.001). The PearlDiver < 65 sub-cohort also had increased 30- (RR: 1.53 (1.40-1.67)) and 90-day (RR: 1.56 (1.47-1.66)) post-operative complications compared to MarketScan. Overall, laterality coding was more prevalent in the PearlDiver database.For those undergoing isolated meniscectomy, the MarketScan database comprised an overall larger and younger cohort of patients with fewer comorbidities, even when examining only subjects under 65 years of age.Level III, retrospective comparative study.

    View details for DOI 10.1016/j.arthro.2020.09.013

    View details for PubMedID 32966865

  • Soaking of Autologous Tendon Grafts in Vancomycin Before Implantation Does Not Lead to Tenocyte Cytotoxicity. The American journal of sports medicine Xiao, M., Leonardi, E. A., Sharpe, O., Sherman, S. L., Safran, M. R., Robinson, W. H., Abrams, G. D. 2020: 363546520951815


    Surgical site infections (SSIs) after anterior cruciate ligament (ACL) reconstruction procedures are an unfortunate complication. Soaking grafts in vancomycin before implantation has been reported to reduce the incidence of postoperative SSI after ACL reconstruction. There is potential for vancomycin to compromise graft integrity because of tenocyte toxicity.To examine the in vitro toxicity of varying doses of vancomycin on human tenocytes.Controlled laboratory study.Human patellar tenocytes were isolated and expanded in vitro. Tenocytes in culture were exposed to vancomycin at 5 different concentrations (400, 1600, 3200, 6400, and 12,800 ?g/mL) and 3 time intervals (2, 6, and 24 hours). The control for all series was tenocyte exposure to only culture medium for each time interval. After treatment, a 10% Cell Counting Kit-8 solution in cellular growth medium was applied to the cells to examine cytotoxicity. A live/dead assay was used to assess tenocyte viability through fluorescence microscopy and flow cytometry. Results were analyzed statistically using multivariable logistic regression models with Tukey honest significant difference post hoc tests.Vancomycin did not cause significant changes in tenocyte viability after 2 and 6 hours of incubation at any concentration between 0 and 12,800 µg/mL. Incubation with vancomycin for 24 hours led to a significant decrease in cell viability at higher concentrations.Tenocytes derived from human patellar tendons exposed to relatively high concentrations of vancomycin for short periods of time do not demonstrate significant cell death and toxicity.Exposing tendons to vancomycin for a short period of time, such as before ACL reconstruction, is not likely to cause tenocyte toxicity because of vancomycin administration.

    View details for DOI 10.1177/0363546520951815

    View details for PubMedID 32898431

  • Exogenous micro-RNA and antagomir modulate osteogenic gene expression in tenocytes EXPERIMENTAL CELL RESEARCH Xiao, M., Iglinski-Benjamin, K. C., Sharpe, O., Robinson, W. H., Abrams, G. D. 2019; 378 (2): 119?23
  • Exogenous Micro-RNA and Antagomir Modulate Osteogenic Gene Expression in Tenocytes. Experimental cell research Xiao, M., Iglinski-Benjamin, K. C., Sharpe, O., Robinson, W. H., Abrams, G. D. 2019


    Tendinopathy is a common and disabling condition that is difficult to treat. The pathomolecular events behind tendinopathy remain uncertain. Micro-RNAs (miRNAs, miRs) are short non-coding RNAs that regulate gene expression and may play a role in tendinopathy development. Tenocytes were obtained from human patellar tendons in patients undergoing anterior cruciate ligament (ACL) reconstruction. Micro-RNA mimics and antagomirs for miR-30d, 26a, and 29a were separately transfected into tenocyte culture. Gene expression for scleraxis, collagen 1 alpha 1 (COL1A1), collagen 3 alpha 1 (COL3A1), interleukin-1-beta (IL-1beta), interleukin-6 (IL-6), bone morphogenic protein 2 (BMP2), bone morphogenic protein 12 (BMP12), and osteocalcin was determined for each miRNA mimic and antagomir transfection using real-time quantitative PCR (qPCR). The results showed that exogenous miR-29a downregulated BMP2 and BMP12, while miR-26a and miR-30d did not have a significant effect on tenocyte gene expression. These findings suggest miR-29a contributes to tendon homeostasis and can serve as a potential therapeutic target in treating tendinopathy.

    View details for PubMedID 30849310

  • Increased Prevalence of Concomitant Psychiatric Diagnoses Among Patients Undergoing Hip Arthroscopic Surgery ORTHOPAEDIC JOURNAL OF SPORTS MEDICINE Iglinski-Benjamin, K. C., Xiao, M., Safran, M. R., Abrams, G. D. 2019; 7 (1)
  • Increased reoperation rates among patients undergoing shoulder arthroscopy with concomitant biceps tenodesis. JSES open access Xiao, M., Abrams, G. D. 2019; 3 (4): 344?49


    The purpose of this study was to determine whether patients undergoing any shoulder arthroscopic procedure with concomitant biceps tenodesis have higher reoperation and complication rates vs. patients undergoing shoulder arthroscopy without concomitant biceps tenodesis.A large database was queried for patients undergoing shoulder arthroscopy, identified by Current Procedural Terminology code. Only records indicating the laterality of the procedure were included. Patients were divided into 3 cohorts: arthroscopic shoulder surgery without concomitant biceps tenodesis (group 1), surgery with arthroscopic biceps tenodesis (group 2), and surgery with open biceps tenodesis (group 3). Reoperations on the same shoulder, as well as medical or surgical complications (by International Classification of Diseases, Ninth Revision code) during the 30-day postoperative period, were determined. Multivariate logistic regression was used to control for differences in age, sex, and Charlson Comorbidity Index between groups.We identified 62,461 patients (54.3% male patients) in the database who underwent shoulder arthroscopy, with 51,773 patients in group 1, 7134 patients in group 2, and 3554 patients in group 3. Overall, 3134 patients (5.0%) underwent a shoulder arthroscopy reoperation. With adjustment for age, sex, and Charlson Comorbidity Index, the biceps intervention groups demonstrated a significantly higher overall reoperation rate (odds ratio, 1.3 [95% confidence interval, 1.2-1.5]; P < .001). Patients undergoing biceps tenodesis had a lower adjusted overall 30-day complication rate vs. those not undergoing tenodesis (odds ratio, 0.82 [95% confidence interval, 0.79-0.86]; P < .001).Reoperation rates were significantly higher in patients undergoing shoulder arthroscopy with biceps tenodesis than in patients undergoing shoulder arthroscopy without biceps tenodesis. Both the arthroscopic and open tenodesis groups had significantly lower complication rates.

    View details for DOI 10.1016/j.jses.2019.08.002

    View details for PubMedID 31891037

    View details for PubMedCentralID PMC6928255

  • Increased Prevalence of Concomitant Psychiatric Diagnoses Among Patients Undergoing Hip Arthroscopic Surgery. Orthopaedic journal of sports medicine Iglinski-Benjamin, K. C., Xiao, M., Safran, M. R., Abrams, G. D. 2019; 7 (1): 2325967118822451


    Active patients with musculoskeletal pain are not immune to psychological or psychiatric disease. Observations suggest that patients undergoing hip arthroscopic surgery may have an increased prevalence of comorbid psychiatric conditions.Patients undergoing hip arthroscopic surgery have an increased prevalence of concomitant psychiatric diagnoses compared with the general population as well as those undergoing anterior cruciate ligament (ACL) reconstruction.Case-control study; Level of evidence, 3.A retrospective review of a medical claims database spanning from 2007 to 2016 was utilized to identify patients with a Current Procedural Terminology (CPT) code indicating that they had undergone hip arthroscopic surgery. This group was then dichotomized to those with or without an International Classification of Diseases, 9th Revision (ICD-9) and 10th Revision (ICD-10) diagnosis code indicating a psychological or psychiatric condition at any time before hip arthroscopic surgery or up to 2 years after hip arthrscopic surgery. As a control, ICD-9 and ICD-10 diagnosis codes for psychological or psychiatric conditions were determined in patients without a CPT code for hip arthroscopic surgery (general population) as well as for 2 surgical groups: those undergoing ACL reconstruction and those undergoing shoulder stabilization surgery. Prevalence was determined in all groups and compared using chi-square analysis.There were 22,676,069 patients in the database, with 2428 undergoing hip arthroscopic surgery. Those undergoing hip arthroscopic surgery had a 3-fold increased prevalence of concomitant psychiatric diagnoses compared with the general population (52% vs 17%, respectively; P < .0001). There was a significant difference in the prevalence of psychiatric diagnoses in the hip arthroscopic surgery group between male and female patients (46% vs 56%, respectively; P = .0061), with depression and anxiety being the 2 most common comorbid conditions. Those undergoing hip arthroscopic surgery also had a significantly increased prevalence of concomitant psychiatric diagnoses versus those undergoing ACL reconstruction (52% vs 28%, respectively; P < .0001) as well as those undergoing shoulder stabilization surgery (52% vs 42%, respectively; P < .0001).Patients undergoing hip arthroscopic surgery had an increased prevalence of comorbid psychiatric conditions compared with the general population as well as those undergoing ACL reconstruction or shoulder stabilization surgery. Depression and anxiety were the most prevalent concomitant psychiatric diagnoses.

    View details for PubMedID 30719482

  • Design and synthesis of new piperidone grafted acetylcholinesterase inhibitors BIOORGANIC & MEDICINAL CHEMISTRY LETTERS Basiri, A., Xiao, M., McCarthy, A., Dutta, D., Byrareddy, S. N., Conda-Sheridan, M. 2017; 27 (2): 228?31


    Alzheimer's disease (AD) is a neurodegenerative disorder affecting 35million people worldwide. A common strategy to improve the well-being of AD patients consists on the inhibition of acetylcholinesterase with the concomitant increase of the neurotransmitter acetylcholine at cholinergic synapses. Two series of unreported N-benzylpiperidines 5(a-h) and thiazolopyrimidines 9(a-q) molecules were synthesized and evaluated in vitro for their acetylcholinesterase (AChE) inhibitory activities. Among the newly synthesized compounds, 5h, 9h, 9j, and 9p displayed higher AChE enzyme inhibitory activities than the standard drug, galantamine, with IC50 values of 0.83, 0.98, and 0.73?M, respectively. Cytotoxicity studies of 5h, 9h, 9j, 9n and 9p on human neuroblastoma cells SH-SY5Y, showed no toxicity up to 40?M concentration. Molecular docking simulations of the active compounds 5h and 9p disclosed the crucial role of ?-?-stacking in their binding interaction to the active site AChE enzyme. The presented compounds have potential as AChE inhibitors and potential AD drugs.

    View details for DOI 10.1016/j.bmcl.2016.11.065

    View details for Web of Science ID 000392558500022

    View details for PubMedID 27914796

    View details for PubMedCentralID PMC5518470

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