Comparison of preventive effect of seat belt on traumatic brain injury by age in motor vehicle collision

Objective@#This study examined whether the preventive effects of the safety belt on traumatic brain injury (TBI) from motor vehicle collisions (MVCs) differ according to the occupants’ age. @*Methods@#This study was a retrospective, observational study. This study evaluated the crash data from 2011 to 2016 obtained from the Emergency Department-based Injury In-depth Surveillance registry. The injured occupants were categorized by age into young adults (age, 18-35 years; n=35,032), middle-aged adults (age, 36-55 years; n=34,507), and older adults (aged older than 55 years, n=21,895). The primary (TBI), secondary (intensive care unit [ICU] admission), and tertiary endpoint (mortality) were set. Multivariate logistic regression analysis was performed, and the adjusted odds ratios (aORs) of subgroups were calculated for study outcomes adjusted for any potential confounders. @*Results@#Among 91,434 patients, 61,205 used seat belts at the time of the crashes. Compared to the unbelted group, the belted group was less likely to have a TBI. A comparison of the aOR of subgroups for TBI revealed the odds ratio reduction to be the highest in young adults (aOR, 0.39; 95% confidence interval [CI], 0.32-0.47), followed by middle-aged adults (aOR, 0.39; 95% CI, 0.33-0.47) and older adults (aOR, 0.49; 95% CI, 0.42-0.56). In addition, seat belt use had a preventive effect on ICU admission and mortality at all subgroups, the effect of which decreased with age. @*Conclusion@#The protective effects of seat belts on TBI, ICU admission, and mortality from MVCs were reduced with age.

Comparison of preventive effect of seat belt on traumatic brain injury by age in motor vehicle collision

Objective@#This study examined whether the preventive effects of the safety belt on traumatic brain injury (TBI) from motor vehicle collisions (MVCs) differ according to the occupants’ age. @*Methods@#This study was a retrospective, observational study. This study evaluated the crash data from 2011 to 2016 obtained from the Emergency Department-based Injury In-depth Surveillance registry. The injured occupants were categorized by age into young adults (age, 18-35 years; n=35,032), middle-aged adults (age, 36-55 years; n=34,507), and older adults (aged older than 55 years, n=21,895). The primary (TBI), secondary (intensive care unit [ICU] admission), and tertiary endpoint (mortality) were set. Multivariate logistic regression analysis was performed, and the adjusted odds ratios (aORs) of subgroups were calculated for study outcomes adjusted for any potential confounders. @*Results@#Among 91,434 patients, 61,205 used seat belts at the time of the crashes. Compared to the unbelted group, the belted group was less likely to have a TBI. A comparison of the aOR of subgroups for TBI revealed the odds ratio reduction to be the highest in young adults (aOR, 0.39; 95% confidence interval [CI], 0.32-0.47), followed by middle-aged adults (aOR, 0.39; 95% CI, 0.33-0.47) and older adults (aOR, 0.49; 95% CI, 0.42-0.56). In addition, seat belt use had a preventive effect on ICU admission and mortality at all subgroups, the effect of which decreased with age. @*Conclusion@#The protective effects of seat belts on TBI, ICU admission, and mortality from MVCs were reduced with age.

Avidity of serum immunoglobulin G antibodies to Porphyromonas gingivalis in the elderly with chronic periodontitis

The present study aimed at evaluating serum immunoglobulin G (IgG) avidity to Porphyromonas gingivalis in elderly patients with mild and severe chronic periodontitis. The avidity of antibodies against P. gingivalis present in the sera of 18 patients with mild chronic periodontitis and 18 patients with severe chronic periodontitis was evaluated using an ammonium thiocyanate-dissociated enzyme-linked immunosorbent assay (ELISA). The results showed that the mean absorbance value in serum IgG antibody titers was significantly higher in the severe chronic periodontitis group than in the mild chronic periodontitis group (198 ± 35 ELISA unit [EU] vs. 142 ± 32 EU, p < 0.01). However, there was no significant difference between the two groups in antibody avidity (65 ± 57 EU vs. 54 ± 27 EU). These findings suggest that humoral immune responses to P. gingivalis between mild and severe chronic periodontitis in elderly patients are characterized by the differences in the quantity rather than the quality of the antibodies.

Impact of discharge against medical advice on emergency department revisit among suicide attempters

OBJECTIVE: This study examined the clinical effects of discharge against medical advice (DAMA) on suicide reattempts and clarified the risk factors related to DAMA. METHODS: A cross-sectional observational study was conducted in the emergency department (ED) of Chungbuk National University Hospital from 2015 to 2017. The medical records of suicide attempters from the National Emergency Department Information System were reviewed. The primary outcome was the ED revisit rate. The characteristics of the patients associated with DAMA were also examined. RESULTS: Among 889 eligible suicide attempters, 328 patients (36.9%) were reported to have DAMA at least once during the study period. Patients who were discharged against medical advice were more likely to reattempt suicide compared to normal disposition patients (11.0% vs. 3.7%, adjusted odds ratio [AOR], 3.002; 95% confidence interval [CI], 1.71–5.28). The independent risk factors for DAMA were age≤60 (AOR, 1.77; 95% CI, 1.20–2.59), female (AOR, 1.45; 95% CI, 1.09–1.91), ED visit at night time (AOR, 1.41; 95% CI, 1.03–1.92), and ED discharge at night time (AOR, 1.40; 95% CI, 1.06–1.85). CONCLUSION: Patients who were discharged against medical advice revisited the ED more after suicide attempts. Public efforts will be needed for patients who are discharged against medical advice considering those risk factors.

Analysis of risk factors affecting a suicidal attempter exposing suicidal intensions for the development of the active intervention strategy for suicide prevention

OBJECTIVE: This study examined the clinical characteristics of suicide attempters who exposed their suicidal intension to suggest an active intervention strategy for suicide prevention based on the regional emergency medical service system. METHODS: A prospective database of suicide attempters who visited the emergency department of Chungbuk National University Hospital between October 2013 and December 2017 was used. All of the adult patients who provided consent for the initial assessment for suicidal attempters were eligible, excluding cases with unknown exposure of suicidal intension. The primary and secondary endpoints were the risk factors affecting exposure to the suicidal intension and characteristics of the exposure group. The adjusted odds ratios (AORs) of exposure to suicidal attempts after adjusting for potential confounders was calculated. RESULTS: Of a total 1,035 suicidal attempters enrolled, 332 (32.1%) were included in the exposure group. The exposure group was more likely to have an educational level above high school and no religion, and have suicidal characteristics at night time (18:00–08:00), under the influence of alcohol, suicidal plan before 1 week, and suicidal method involving asphyxia (P<0.05). The exposure group was more likely to have no guardian (AORs, 1.46; 95% confidence interval [CI], 1.00–2.12), use methods involving asphyxia (AORs, 2.07; 95% CI, 1.46–2.91), and attempt suicide at night (18:00 to 08:00) (AORs, 1.38; 95% CI, 1.05–1.83) compared to the no exposure group. CONCLUSION: Models need to be established, where regional mental health welfare center, local government, fire headquarter, and tele-communication companies can participate in the implementation of an active intervention strategy.

A Preliminary Study for Effect of High Flow Oxygen through Nasal Cannula Therapy in Carbon Monoxide Poisoning

PURPOSE@#Acute carbon monoxide (CO) poisoning is one of the most common types of poisoning and a major health problem worldwide. Treatment options are limited to normobaric oxygen therapy, administered using a non-rebreather face mask or hyperbaric oxygen. Compared to conventional oxygen therapy, high-flow nasal cannula oxygen (HFNC) creates a positive pressure effect through high-flow rates. The purpose of this human pilot study is to determine the effects of HFNC on the rate of CO clearance from the blood, in patients with mild to moderate CO poisoning.@*METHODS@#CO-poisoned patients were administered 100% oxygen from HFNC (flow of 60 L/min). The fraction of COHb (fCOHb) was measured at 30-min intervals until it decreased to under 10%, and the half-life time of fCOHb (fCOHb t(1/2)) was subsequently determined.@*RESULTS@#At the time of ED arrival, a total of 10 patients had fCOHb levels ≥10%, with 4 patients ranging between 10% and 50%. The mean rate of fCOHb elimination patterns exhibits logarithmic growth curves that initially increase quickly with time (HFNC equation, Y=0.3388*X+11.67). The mean fCOHbt1/2 in the HFNC group was determined to be 48.5±12.4 minutes.@*CONCLUSION@#In patients with mild to moderate CO poisoning, oxygen delivered via high flow nasal cannula is a safe and comfortable method to treat acute CO toxicity, and is effective in reducing the COHb half-life. Our results indicate HFNC to be a promising alternative method of delivering oxygen for CO toxicity. Validating the effectiveness of this method will require larger studies with clinical outcomes.

Antibody-based Screening of Porphyromonas gingivalis Proteins Specifically Produced in Patients with Chronic Periodontitis

Porphyromonas gingivalis is among the major etiological pathogens of chronic periodontitis. The virulence mechanisms of P. gingivalis is yet to be identified as its activity is largely unknown in actual disease process. The purpose of this study is to identify antigens of P. gingivalis expressed only in patients with chronic periodontitis using a unique immunoscreening technique. Change Mediated Antigen Technology (CMAT), an antibody-based screening technique, was used to identify virulence-associated proteins of P. gingivalis that are expressed only during infection stage in patients having chronic periodontitis. Out of 13,000 recombinant clones screened, 22 tested positive for reproducible reactivity with rabbit hyperimmune anti-sera prepared against dental plaque samples acquired from periodontitis patients. The DNA sequences of these 18 genes were determined. CMAT-identified protein antigens of P. gingivalis included proteins involved in energy metabolism and biosynthesis, heme and iron binding, drug resistance, specific enzyme activities, and unknown functions. Further analysis of these genes could result in a novel insight into the virulence mechanisms of P. gingivalis.

Surface interactions between two of the main periodontal pathogens: Porphyromonas gingivalis and Tannerella forsythia

PURPOSE: Porphyromonas gingivalis and Tannerella forsythia have been implicated as the major etiologic agents of periodontal disease. These two bacteria are frequently isolated together from the periodontal lesion, and it has been suggested that their interaction may increase each one's virulence potential. The purpose of this study was to identify proteins on the surface of these organisms that are involved in interbacterial binding. METHODS: Biotin labeling of surface proteins of P. gingivalis and T. forsythia and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was performed to identify surface proteins involved in the coaggregating activity between P. gingivalis and T. forsythia. RESULTS: It was found that three major T. forsythia proteins sized 161, 100, and 62 kDa were involved in binding to P. gingivalis, and P. gingivalis proteins sized 35, 32, and 26 kDa were involved in binding to T. forsythia cells. CONCLUSIONS: LC-MS/MS analysis identified one T. forsythia surface protein (TonB-linked outer membrane protein) involved in interbacterial binding to P. gingivalis. However, the nature of other T. forsythia and P. gingivalis surface proteins identified by biotin labeling could not be determined. Further analysis of these proteins will help elucidate the molecular mechanisms that mediate coaggregation between P. gingivalis and T. forsythia.

Identification of Enterococcus faecalis antigens specifically expressed in vivo

OBJECTIVES: Molecular mechanism of the pathogenicity of Enterococcus faecalis (E. faecalis), a suspected endodontic pathogen, has not yet been adequately elucidated due to limited information on its virulence factors. Here we report the identification of in vivo expressed antigens of E. faecalis by using a novel immunoscreening technique called change-mediated antigen technology (CMAT) and an experimental animal model of endodontic infection. MATERIALS AND METHODS: Among 4,500 E. coli recombinant clones screened, 19 positive clones reacted reproducibly with hyperimmune sera obtained from rabbits immunized with E. faecalis cells isolated from an experimental endodontic infection. DNA sequences from 16 of these in vivo-induced (IVI) genes were determined. RESULTS: Identified protein antigens of E. faecalis included enzymes involved in housekeeping functions, copper resistance protein, putative outer membrane proteins, and proteins of unknown function. CONCLUSIONS: In vivo expressed antigens of E. faecalis could be identified by using a novel immune-screening technique CMAT and an experimental animal model of endodontic infection. Detailed analysis of these IVI genes will lead to a better understanding of the molecular mechanisms involved in the endodontic infection of E. faecalis.

Humoral immune responses to periodontal pathogens in the elderly

PURPOSE: Elderly people are thought to be more susceptible to periodontal disease due to reduced immune function associated with aging. However, little information is available on the nature of immune responses against putative periodontal pathogens in geriatric patients. The purpose of this study was to evaluate the serum IgG antibody responses to six periodontal pathogens in geriatric subjects. METHODS: The study population consisted of 85 geriatric patients and was divided into three groups: 29 mild (MCP), 27 moderate (MoCP) and 29 severe (SCP) chronic periodontitis patients. Serum levels of IgG antibody to Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Prevotella intermedia were measured by enzyme-linked immunosorbent assay (ELISA) and compared among the groups. RESULTS: All three groups showed levels of serum IgG in response to P. gingivalis, A. actinomycetemcomitans, and P. intermedia that were three to four times higher than levels of IgG to T. forsythia, T. denticola, and F. nucleatum. There were no significant differences among all three groups in IgG response to P. gingivalis (P=0.065), T. forsythia (P=0.057), T. denticola (P=0.1), and P. intermedia (P=0.167), although the IgG levels tended to be higher in patients with SCP than in those with MCP or MoCP (with the exception of those for P. intermedia). In contrast, there were significant differences among the groups in IgG levels in response to F. nucleatum (P=0.001) and A. actinomycetemcomitans (P=0.003). IgG levels to A. actinomycetemcomitans were higher in patients with MCP than in those with MoCP or SCP. CONCLUSIONS: When IgG levels were compared among three periodontal disease groups, only IgG levels to F. nucleatum significantly increased with the severity of disease. On the contrary, IgG levels to A. actinomycetemcomitans decreased significantly in patients with SCP compared to those with MCP. There were no significant differences in the IgG levels for P. gingivalis, T. forsythia, T. denticola, and P. intermedia among geriatric patients with chronic periodontitis.

Quantitative analysis of periodontal pathogens present in the saliva of geriatric subjects

PURPOSE: At present, information regarding periodontal disease in geriatric patients is scarce. The purpose of this study was to quantify the periodontal pathogens present in the saliva of Korean geriatric patients and assess the relationship between the bacterial levels and the periodontal condition. METHODS: Six putative periodontal pathogens were quantified by using a real-time polymerase chain reaction assay in geriatric patient groups (>60 years) with mild chronic periodontitis (MCP), moderate chronic periodontitis (MoCP), and severe chronic periodontitis (SCP). The copy numbers of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, and Prevotella intermedia were measured. RESULTS: It was found that the bacterial copy numbers increased as the severity of the disease increased from MCP to SCP, except for P. intermedia. For P. intermedia, it was found that samples in the MCP group yielded the largest amount. It was also found that the quantities of P. gingivalis, T. forsythia, and T. denticola, the so-called "red complex" bacteria, were lower than those of F. nucleatum, A. actinomycetemcomitans, and P. intermedia in all of the samples. CONCLUSIONS: Collectively, the results of this study suggest that the levels of P. gingivalis, T. forsythia, F. nucleatum, and T. denticola present in saliva are associated with the severity of periodontal disease in geriatric patients.

Coaggregation between Porphyromonas gingivalis and Tannerella forsythia / 대한치주과학회지

Dental plaque, a biofilm consisting of more than 500 different bacterial species, is an etiological agent of human periodontal disease. It is therefore important to characterize interactions among periodontopathic microorganisms in order to understand the microbial pathogenesis of periodontal disease. Previous data have suggested a synergistic effect of tow major periodontal pathogens Porphyromonas gingivalis and Tannerella forsythia in the periodontal lesion. In the present study, to better understand interaction between P. gingivalis and T. forsythia, the coaggregation activity between these bacteria was characterized. The coaggregation activity was observed by a direct visual assay by mixing equal amount (1 x 10(9)) of T. forsythia and P. gingivalis cells. It was found that the first aggregates began to appear after 5-10 min, and that the large aggregates completely settled within 1 h. Electron and epifluorescence microscopic studies confirmed cell-cell contact between two bacteria. The heat treatment of P. gingivalis completely blocked the activity, suggesting an involvement of a heat-labile component of P. gingivalis in the interaction. On the other hand, heat treatment of T. forsythia significantly increased the coaggregation activity; the aggregates began to appear immediately. The coaggregation activity was inhibited by addition of protease, however carbohydrates did not inhibit the activity, suggesting that coaggregation is a protein-protein interaction. The results of this study suggest that coaggregation between P. gingivalis and T. forsythia is a result of cell-cell physical contact, and that coaggregation is mediated by a heat-labile component of P. gingivalis and T. forsythia component that can be activated on heat treatment.

The biomechanical study of the bone-prosthesis interface stability according to the difference of types of porous-coated acetabular implant / 대한정형외과학회잡지

PURPOSE: To analyze the effects of implant design on the primary stability and the contact between bone and prosthesis of three different porous coated acetabular implants. MATERIALS AND METHODS: The distal part of sixty bovine femurs were employed. 52 mm acetabular cups were inserted tightly after 2mm under-reaming. Trilogy acetabular cups were inserted in Group I, Mallory head finned RingLoc cups in Group II, Duraloc spiked cups in Group III. The gaps between the acetabular cups and the bones were measured on the radiography. The axial compression test and rotation test were performed using Instron. RESULTS: The gaps between the acetabular cup and bone of Gorup I and II was significantly smaller than Group III at its central adjacent and peripheral area (p0.05) . The mean torque of 1 degree rotation test was higher in the Group III than in the group I and II without statistical significance (p>0.05) . The mean torque of 2, 3 and 5 degree rotation test was highest in Group II among three, but there were no statistical differences among three groups (p>0.05) . CONCLUSION: Triology and Mallory-Head cup can be assumed to have better primary stability than Duraloc cup. And additional fin or spikes attached on the acetabular implant couldn't enhance the primary bone-prosthesis interface stability.

Anesthetic Management for Cervicothoracic Sympathectomy in a Patient with Congenital Long QT Syndrome / 대한마취과학회지

A 23-year-old female patient was diagnosed with congenital long QT syndrome, discovered when she visited our cardiac department due to chest discomfort, because she had a prolonged QTc interval on ECG, history of syncopal attacks and seizures several times every year, and ingestion of anticonvulsants for several years. It is well known that the long QT syndrome is associated with sudden death secondary to ventricular tachyarrhythmia or fibrillation at a young age. Moreover cardiac arrests during induction, maintenance, and awakening of anesthesia of these patients have been reported, and may be due to asymmetrical adrenergic stimuli in the heart, especially in the unrecognised case. This case report describes the anesthetic management of a patient with congenital long QT syndrome, who presented for cervicothoracic sympathectomy for a more permanent control of life-threatening ventricular arrhythmias, and reviews the related literature.

The Effect of Famotidine on Lowering Gastric Acidity in Gastric Carcinoma Patients / 대한마취과학회지

BACKGROUND: To identify the gastric pH of gastric carcinoma patients after more than 8 hours of fasting and ascertain the antisecretory effects of H2-receptor antagonists, the gastric volume and pH of 41 gastric carcinoma patients was checked immediately after the induction of inhalational general anesthesia (endotracheal intubation). METHODS: The patients were divided randomly into two groups: the control received IV normal saline as a placebo and the famotidine group received IV famotidine as a premedicant 1 to 2 hours before the induction of anesthesia. Immediately after the induction of anesthesia, the gastric contents were aspirated blindly with a 60 ml syringe. Fisher's exact test was used to compare the percentage of patients 'at risk' between the two groups in relation to their pH and volumes. RESULTS: The percentage of patients 'at risk' (volume > 0.4 ml/kg and pH < 2.5) of acid aspiration pneumonitis in the control and famotidine groups was 8.7% and 5.6%, respectively, which was 30 77% lower than for patients with no premedication, as observed in other studies. In the present study, the difference in percentage of patients 'at risk' between the two groups was not statistically significant. CONCLUSIONS: The gastric carcinoma patients exhibited a higher gastric pH when fasting and a lower risk of acid aspiration pneumonitis relative to their gastric contents. The effect of famotidine on lowering gastric acidity and volume in gastric carcinoma patients was rather weak. Accordingly, the routine use of H2-receptor antagonists to decrease gastric secretion in gastric carcinoma patients should be reevaluated.

The Effects of Preanesthetic Low Dose Famotidine on Gastric pH and Volume in Children / 대한마취과학회지

BACKGROUND: Children undergoing general anesthesia are at increased risk of aspiration pneumonia. Cimetidine and ranitidine, specific histamine (H2-receptor) antagonists, markedly reduce the acidity and volume of gastric content when given 2 3h preoperatively. A newer compound, famotidine, is a more specific antagonist that has no inhibitory effect on the drug metabolizing microsomal enzyme systems of the liver (cytochrome P-450), in contrast to cimetidine. An additional clinical advantage is a possible longer duration of action. The aim of this study is to evaluate the lowest effective dose of famotidine on gastric pH and volume in children. METHODS: Fifty-five children, aged 2 to 14 years (ASA physical status I-II) were divided into four groups (Group I:placebo, normal saline 10 ml, Group II:famotidine 0.1 mg/kg, Group III:famotidine 0.15 mg/kg, Group IV:famotidine 0.2 mg/kg.). Doses were administered intravenously 2 or 3 hours before the operation. Following induction with oxygen, enflurane and pentothal sodium, anesthesia was maintained with N2O/O2 and enflurane. A nasogastric tube was passed into the stomach and the gastric contents were aspirated in a uniform manner. Gastric volume was recorded and pH values were measured with pH meter. The incidence of high risk for aspiration pneumonia, defined as gastric pH 0.4 ml/kg of gastric juice, was measured in all groups. RESULTS: In the placebo group, 10 of 13 children (77%) had a pH 0.4 ml/kg. Group II (famotidine 0.1 mg/kg) was not found to produce a significant increase in the gastric pH. Groups III and IV (famotidine 0.15 mg/kg and 0.2 mg/kg) were found to produce a significant increase in the gastric pH. The gastric juice volume was reduced in all famotidine groups, but was not statistically significant compared with the placebo group. The incidences of high risk for aspirationpneumonitis decreased in all famotidine groups. CONCLUSIONS: The results suggest that the preoperative intravenous administration of famotidine 0.15 mg/kg is enough to decrease both gastric juice acidity and volume in this high-risk group.

Isolated Bacteria and Their Susceptibility to Antibiotics in Chronic Sinusitis : Results of Endoscopically Guided Cultures of Maxillary Sinus Secretions

The aim of this study was to identify the pathogens of chronic recalcitrant sinusitis and to obtain information for determining appropriate antibiotics through sensitivity testing. A prospective study was conducted on 100 patients with chronic sinusitis who had undergone endoscopic sinus surgery after failed medical treatment. Specimens were obtained from the maxillary sinuses and sent for bacterial cultures and sensitivity tests. Bacteria were isolated in 75 (75%) of the 100 cases. Aerobic bacteria were isolated in 73 cases (73%). Gram-positive aerobes were recovered in 54 cases (54%) and Gram-negative aerobes in 20 cases (20%). Anaerobes were isolated in three cases (3%). Mixed infections were found in two cases (2%). More than 90% of the aerobic bacteria were resistant to penicillin, and 48.8% of the Staphylococci were resistant to oxacillin. Seventy percent of Gram-positive aerobes were sensitive to trimethoprim-sulfamethoxazole, 75% to clindamycin, and 93% to ciprofloxacin. Ninety percent of Gramnegative aerobes were sensitive to ciprofloxacin, and 95% to trimethoprim-sulfamethoxazole. In conclusion, most of the isolated bacteria were aerobic, and in contrast to previous reports, mixed or anaerobic bacterial infection was not frequent. Among the oral antibiotics tested for sensitivity in this study, ciprofloxacin, trimethoprim-sulfamethoxazole, and clindamycin are most strongly recommended for treating chronic sinusitis refractory to first-line antibiotic treatment.

Avascular Necrosis of the Femoral Head : Correlation of Magnetic Resonance Imaging, Radiograph, Radionuclide Imaging, and Histological Findings / 대한정형외과학회잡지

Magnetic resonance imaging(MRI) appears to be the most sensitive modality for early diagnosis of avascular necrosis of the femoral head and has recently been recommanded as a means of strengthening individual treatment decisions, However, MR signal patterns in AVN has been described to vary widely. And the understanding of the anatomic and pathologic structures represented on the MRI thus appears desirable for improved tissue characterization, staging of disease, and therapeutic planning. The object of this study was to analyze the correlation of MRI, radiographic staging, radionuclide imaging, and histological findings in AVN of the femoral head. The authors analyzed retrospectively 30 patients(36 hips) of AVN of the femoral head who underwent bipolar hemiarthroplasty or total hip replacement arthroplasty at Korea University Hospital from Nov. 1990 to Oct. 1993. The radiographic stage was evaluated according to Ficat and Arlet classification, and MRI was evaluated according to Mitchell et al. classification. The histologic changes corresponding to MRI abnormalities were assessed in 10 fresh surgical specimens. The obtained results were as follows; 1. Nine cases (25%) were class A, 3 class B (8%), 6 class C (17%) and 18 class D(50%) by Michell et al. classification on MRI and typical double line sign was found in 20 cases(56%). 2. Most of the cases of Ficat and Arlet stage II in simple radiograph showed MR class A or B, and stage III and IV showed class C or D. 3. There cases(10%) showed false negative studies in radionuclide imaging. 4. The necrotic bone & marrow and amorphous cellular debris represented the low signal intensity on both T1WI and T2WI, and repairing tissue, thickened trabeculae with mesenchymal cell infiltration was low signal intensity in T1WI and intermediate signal intensity in T2WI, and fibrous tissue was low signal intensity on both T1WI and T2WI. 5. MR classification by Mitchell et al. was not correlated with histological finding in respect of progression. Above results suggest that MRI provide the information about accurate anatomical location and involved site of necrosis, while MR classification by Mitchell et al. was not useful for staging of pathogenic process of AVN of the femoral head. The therapeutic plan and modalities have to be estabilished by comprehensive analysis of MRI, simple radiograph and other diagnostic modalities.

Surgical treatment of thoracolumbar fractures with transpedicular screws / 대한정형외과학회잡지

No abstract available.

A clinical study of the tibial condylar fractures / 대한정형외과학회잡지

No abstract available.