Outcomes with culture-directed antibiotics following microvascular free tissue reconstruction for osteonecrosis of the jaw.

OBJECTIVES: Radiation (ORNJ) and bisphosphonate-related (BRONJ) osteonecrosis of the jaw represent challenging entities to treat, with many patients requiring segmental resection and reconstruction with microvascular free tissue transfer (MFTT) in the setting of failed conservative therapy. Microvascular reconstruction is associated with higher post-operative complication rates when performed for advanced osteonecrosis versus oncologic defects. We hypothesize that basing antibiotic therapy on cultures obtained from the healthy bone marrow following resection during MFTT for ORNJ or BRONJ reduces rates of post-operative wound and surgical complications. MATERIALS AND METHODS: In a retrospective cohort study spanning January 2016 to October 2018, 44 patients undergoing MFTT for ORNJ or BRONJ were identified. Patients were categorized into two cohorts: residual healthy marrow culture (n = 11; RHM), treated with antibiotics guided by cultures from healthy appearing mandible, and all others (n = 33; AO), treated with antibiotics guided by cultures from resected necrotic bone or purulent drainage. Patient, reconstruction, and outcome variables were compared via appropriate statistical tools. RESULTS: 81.8% of the RHM cohort versus 24.2% of the AO cohort received long-term IV antibiotics. Rates of post-operative wound complications, including those necessitating operative management, were significantly lower in the RHM cohort. Rates of flap failure were similar across both groups. CONCLUSION: Administration of long-term IV antibiotics directed by native mandible cultures may decrease complication rates following MFTT for ORNJ or BRONJ by treating residual, smoldering infection. Concurrently, transplantation of well-vascularized free tissue likely improves antibiotic delivery. Findings are crucial for the development of a standardized treatment algorithm following microvascular reconstruction for advanced osteonecrosis.

Using the Craniovertebral Angle to Quantify Intraoperative Ergonomic Risk.

OBJECTIVE: To measure the craniovertebral angle during tonsillectomy, assess the interrater reliability of our methodology, and investigate the correlations of the Rapid Upper Limb Assessment and the craniovertebral angle to quantify ergonomic risk. STUDY DESIGN: Prospective, observational study. SETTING: Tertiary care pediatric institution. METHODS: Neck posture was evaluated for 92 images with 7 surgeons. Lateral images of the surgeon were captured every minute in a standardized method. Images were assessed by 3 raters, measuring the craniovertebral angle, defined as the angle between a horizontal line through the C7 vertebrae and another line through C7 and the tragus of the ear. Interrater reliability of the craniovertebral angle was evaluated using the κ statistic. Per prior publications, reports of neck pain were frequent when the craniovertebral angle value was <50°; thus, we defined an abnormal posture if the craniovertebral angle was <50°. RESULTS: Mean (SD) craniovertebral angle during tonsillectomy was 26.0° (11.3°). One hundred percent of procedures had at least 1 assessment of abnormal posture. The lowest interrater reliability was 0.77 (CI: 0.67-0.87). Rapid Upper Limb Assessment and craniovertebral angle (CA) correlation was -0.12 (P = .27) and, therefore, null. CONCLUSION: Poor posture during tonsillectomy places otolaryngologists at intraoperative ergonomic risk. The craniovertebral angle is a predictor of future neck pain, and a pathologic neck position during tonsillectomy was identified. Given the high interrater reliability, our approach to assessing intraoperative surgical ergonomics was validated. Overall, RULA and the CA are not a substitute for one another but complementary.

Anticoagulation management following left ventricular assist device implantation is similar across all provider strategies.

OBJECTIVES: Thromboembolic and bleeding events are potential complications following left ventricular assist device implantation. A tight control of the international normalized ratio (INR) is believed to be crucial in the reduction of postimplant complications. There is significant variability among institutions as to whether a device implanting centre should be managing the INR. In this study, we evaluated the effect of INR management strategies in maintaining a therapeutic INR. METHODS: A retrospective review was utilized to identify patients implanted with either the HeartMate II or the HeartWare HVAD between January 2011 and February 2016. Patients were stratified into 4 groups based on the post-discharge INR management strategy: outside hospital system anticoagulation clinic, outside hospital primary care provider, implanting centre anticoagulation clinic or implanting centre ventricular assist device office. The INR data were collected and analysed for both the early (discharge, 7, 14, 21 and 30 days) and late (3, 6, 9 and 12 months) postoperative periods. RESULTS: There were 163 patients identified during the study period who met the study inclusion criteria: 49 (30%) patients were managed by an outside hospital system anticoagulation clinic, 59 (36.2%) patients by an outside hospital physician/primary care provider, 22 (13.5%) patients by the implanting centre anticoagulation clinic and 33 (20.2%) patients by the implanting centre ventricular assist device office. There were no statistically significant differences found between management strategies across all time points. CONCLUSIONS: There was no statistically significant difference found between the management strategies examined. Regardless of the chosen INR management strategy, patients have similar INR values and postoperative outcomes.

Chick embryo extract demethylates tumor suppressor genes in osteosarcoma cells.

BACKGROUND: Epigenetics is the study of changes in gene expression or cellular phenotype caused by mechanisms other than changes in the underlying DNA sequence. It is widely accepted that cancer has genetic and epigenetic origins. The idea of epigenetic reprogramming of cancer cells by an embryonic microenvironment possesses potential interest from the prospect of both basic science and potential therapeutic strategies. Chick embryo extract (CEE) has been used for the successful expansion of many specific stem cells and has demonstrated the ability to facilitate DNA demethylation. QUESTIONS/PURPOSES: The current study was conducted to compare the status of DNA methylation in highly metastatic and less metastatic osteosarcoma cells and to investigate whether CEE may affect the epigenetic regulation of tumor suppressor genes and thus change the metastatic phenotypes of highly metastatic osteosarcoma cells. METHODS: K7M2 murine OS cells were treated with CEE to determine its potential effect on DNA methylation, cell apoptosis, and invasion capacity. RESULTS: Our current results suggest that the methylation status of tumor suppressor genes (p16, p53, and E-cadherin) is significantly greater in highly metastatic mouse ostoesarcoma K7M2 cells in comparison with less metastatic mouse osteosarcoma K12 cells. CEE treatment of K7M2 cells caused demethylation of p16, p53, and E-cadherin genes, upregulated their expression, and resulted in the reversion of metastatic phenotypes in highly metastatic osteosarcoma cells. CONCLUSIONS: CEE may promote the reversion of metastatic phenotypes of osteosarcoma cells and can be a helpful tool to study osteosarcoma tumor reversion by epigenetic reprogramming. CLINICAL RELEVANCE: Demethylation of tumor suppressor genes in osteosarcoma may represent a novel strategy to diminish the metastatic potential of this neoplasm. Further studies, both in vitro and in vivo, are warranted to evaluate the clinical feasibility of this approach as an adjuvant to current therapy.