Biomedical subjects

J A Fialkov

Publications and source records attributed to J A Fialkov.

8 recordsLinked to original sources

PubMed2003

Use of a biomimetic strategy to engineer bone.

Engineering trabecular-like, three-dimensional bone tissue throughout biodegradable polymer scaffolds is a significant challenge. Using a novel processing technique, we have created a biodegradable scaffold with geometry similar to that of trabecular bone. When seeded with bone-marrow cells, new bone tissue, the geometry of which reflected that of the scaffold, was evident throughout the scaffold volume and to a depth of 10 mm. Preseeded scaffolds implanted in non-healing rabbit segmental bone defects allowed new functional bone formation and bony union to be achieved throughout the defects within 8 weeks. This marks the first report of successful three-dimensional bone-tissue engineering repair using autologous marrow cells without the use of supplementary growth factors. We attribute our success to the novel scaffold morphology.

Animals↗

PubMed2002

Autosomal dominant craniometaphyseal dysplasia with atypical features.

Craniometaphyseal dysplasia (CMD) is a rare genetic disorder of bone modelling characterised by hyperostosis and sclerosis of the craniofacial bones, and abnormal modelling of the metaphyses. Clinically, autosomal dominant (AD) CMD is characterised by facial distortion and cranial-nerve compression. The goals of surgical treatment for AD CMD are cosmetic recontouring of the sclerotic craniofacial bones, correction of nasal obstruction and correction or prevention of neurological manifestations. We describe the successful correction of AD CMD craniofacial manifestations in an individual with atypical findings, and outline an approach for correcting the craniofacial deformities associated with this rare disorder.

Adult↗

PubMed2001

Postoperative infections in craniofacial reconstructive procedures.

The rate of, and possible risk factors for, postoperative craniofacial infection is unclear. To investigate this problem, we reviewed 349 cases of craniofacial skeletal procedures performed from 1996 to 1999 at our institution. Infection rate was determined and correlated with the use of implants, operative site, and cause of deformity. The inclusion criteria consisted of all procedures requiring autologous or prosthetic implantation in craniofacial skeletal sites, as well as all procedures involving bone or cartilage resection, osteotomies, debridement, reduction and/or fixation. Procedures that did not involve bone or cartilage surgery were excluded. The criteria for diagnosis of infection included clinical confirmation and one or more of 1) intravenous or oral antibiotic treatment outside of the prophylactic surgical regimen; 2) surgical intervention for drainage, irrigation, and or debridement; and 3) microbiological confirmation. Among the 280 surgical cases that fit the inclusion criteria and had complete records, there were 23 cases of postoperative infection (8.2%). The most common site for postoperative infection was the mandible (infection rate = 16.7%). Multiple logistic regression analysis revealed gunshot wound to be the most significant predictor of postoperative infection. Additionally, porous polyethylene implantation through a transoral route was correlated with a significant risk of postoperative infection.

Adult↗

PubMed1996

Warmed local anesthetic reduces pain of infiltration.

The effect of warming local anesthetic on the amount of pain experienced during local infiltration was tested by comparing equal volumes of 40 degrees C- and 21 degrees C-infiltrates in each of 26 subjects. Six subjects were patients undergoing excision of two benign asymptomatic nevi in separate locations, and 20 subjects were healthy adult volunteers who were injected in bilateral antebrachial sites. The warmed and room temperature solutions were randomized to each side, so that each subject received both temperature injections in random order. All subjects and the injector were blinded. The rate of injection was time-controlled (0.05 ml/sec). Following both injections, subjects were asked to rate the pain experienced at each site. In addition, the subject was asked if there was no difference, a slight difference, or a substantial difference between the two sites. A two-tailed paired t-test was used to analyze the mean difference in pain scores for all subjects. Paired analysis of the pain scores for each subject eliminated intersubject variance of pain tolerance. The mean difference in pain score between the room temperature and warmed solutions was +1.5 (p < 0.0001). Of the 21 subjects (81%) who found the warmed solution less painful, 11 (52%) found the difference to be significant, while 10 (48%) found the difference to be slight. Two subjects (8%) found no difference between the two, while 3 subjects (11%) found the colder solution slightly less painful. We conclude that warming local anesthetic to 40 degrees C prior to subcutaneous injection is a simple, inexpensive means of reducing the pain of local infiltration.

Adult↗

PubMed1996

The effect of infection and lag screw fixation on revascularization and new bone deposition in membranous bone grafts in a rabbit model.

We have suggested that rigid fixation of membranous bone grafts in the presence of infection may improve graft-recipient bone union by facilitating graft revascularzation. To test this hypothesis, we grafted autogenous membranous bone grafts to the mandibles of 94 New Zealand White rabbits. Lag screw fixation was applied in half the animals. The wounds were inoculated with a range of Staphylococcus aureus doses. Infected and noninfected rabbits were injected weekly over a 5-week course with fluorescein bone markers and with a marker of vascular endothelium (procion red) just prior to sacrifice. Revascularization and new bone deposition in the grafts were then quantified histologically for the 75 rabbits available for data collection. Infection decreased the amount of graft revascularized and the amount of new bone deposited for both rigidly fixated and nonfixated grafts. Grafts fixated with a lag screw showed a greater amount of revascularization and new bone deposition in the presence and absence of infection when compared with nonfixated grafts, supporting the hypothesis that rigid fixation of membranous bone grafts in the presence of infection may promote graft survival and union by improving revascularization and osteogenesis within the graft.

Animals↗

PubMed1994

The effect of infection and lag screw fixation on the union of membranous bone grafts in a rabbit model.

Infection complicating craniofacial procedures contributes significantly to patient morbidity and health care costs. The role of fixation materials in this setting remains unclear. As foreign material, does fixation hardware increase patients' susceptibility to developing postoperative infection? Furthermore, once infection is established, should fixation hardware be removed? To answer these questions, we performed an onlay membranous bone grafting procedure to the mandible in 94 New Zealand White rabbits, applied lag-screw fixation in half the animals, and inoculated the wounds with different bacterial doses. We quantified the differential rates of infection and rates of graft union in the presence of infection. The infection rates for the rigidly fixated group were not significantly different from the rates for the nonfixated group for a range of bacterial inoculum doses. There was no significant difference in the rates of resolution of infection and sepsis between the two groups. Gross and histologic assessments revealed a significantly lower union rate for infected grafts when compared with uninfected grafts. Furthermore, grafts rigidly fixated with a lag screw showed a higher rate of union when compared with nonfixated grafts in the presence of infection. In the absence of infection, the union rates for fixated and nonfixated groups did not differ significantly. While fixation hardware has been cited as a risk factor for postoperative infection, we were unable to show that lag-screw fixation contributes to this risk. Although infection impaired the union of membranous bone grafts to the recipient mandible, fixation of the grafts with a lag screw significantly decreased this deleterious effect of infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

A stereotactic system for guiding complex craniofacial reconstruction.

A stereotactic system has been designed to address the problem of achieving symmetry in complex and extensive craniofacial defects. Preliminary testing suggests that such a system, which allows for the intraoperative application of preoperative CT planning, will be useful in guiding the reconstruction of congenital or acquired bony time, is being used to investigate the correlation of intraoperative globe position following enophthalmos correction with long-term outcome, particularly as it relates to the size and location of the orbital defect, and the timing of the procedure.

Adult↗

PubMedDate not supplied

High pressure injection injuries: an overview.

Injuries resulting from the use of high pressure injectors and spray guns are relatively rare; however, the potential tissue damage caused by the injury as well as the extent of the injury itself may go unrecognized by the primary physician. The purpose of this paper is to inform the emergency physician of the nature and standard management of this type of injury. A basic understanding of the pathophysiology of the high pressure injection injury (HPII) is essential in avoiding the mistakes in management that have been reported in the literature. The emergency management of the HPII includes: evaluation and immobilization, tetanus and antimicrobial prophylaxis, supportive and resuscitative measures, analgesia, and minimizing the time to definitive surgical treatment.

Combined Modality Therapy↗