BACKGROUND: The measurement of carbon monoxide concentration in expired air is used as an objective method to analyze the smoking status. This method has been proven to be reliable and is used throughout the world but it has been only recently accepted in Korea. Therefore the purpose of this study was to examine if measuring the concentration in expired air accurately reflects the Korean's smoking status. METHODS: The subjects were from ages of 19 through 75 healthy people including smokers and nonsmokers. The smokers had their carbon monoxide measured after answering a questionnaire. This questionnaire was formed to obtain information concerning smoking status, smoking habit and factors that influence carbon monoxide measurement. Micro II smokerlyzer (Bedfont Instruments Ltd., England) was used to analyze CO concentration in expired air. The method used for measuring CO concentration was to deeply inhale and hold one's breath for 15 seconds and measure CO concentration while exhaling. RESULTS: The total number of subjects was 148(143 males, 5 females) consisting of 114 smokers, 34 non smokers(never smokers 23, ex smokers 11). The average CO concentration in exhaled air in smokers was 17.247.30 ppm, in nonsmokers 6.031.06 ppm(in ex smokers 6.361.29 ppm, in never smokers 5.870.92 ppm). A significant difference was evident between smokers and non smokers(P<0.0001). The CO concentration values compared among the groups divided in terms of daily smoking rate were as the following 11.885.57 ppm in subjects smoking less than 10 cigarettes/day, 17.356.48 ppm in those smoking 11 20 cigarettes/day, 20.006.35 ppm in the 21 30 cigarettes/day group, and 24.889.70 ppm in the 31 cigarettes/day group (p<0.0001). In addition, the CO concentration was influenced by the change of the degree of inhalation and the elapsed time since last smoking. CONCLUSION: The measurement of CO concentration in exhaled air among the Koreans proved to be an accurate and reliable method reflecting the present smoking status.
Carbon Monoxide* ; Carbon* ; Exhalation ; Humans ; Inhalation ; Korea ; Male ; Smoke* ; Smoking* ; Surveys and Questionnaires

PURPOSE: We evaluated oncologic outcomes of chondrosarcomas and analyzed the disease-free survival rate of chondrosarcomas according to the various factors. MATERIALS AND METHODS: We performed a retrospective study for the disease-free survival rate of 48 chondrosarcomas, 44 of which underwent surgical treatment and followed up more than 18 months since 1993, and in the remaining 4 cases, the patients died before 18 months after surgery. The vsariables were location, tumor volume, histologic grade, stage, age at presentation and treatment performed. The mean follow up period was 43.8 months (1-196 months). RESULTS: The overall disease-free survival rate was 77.1% at mean 43.8 month follow up. The 5 year- and 10 year disease-free survival rates were 64% and 58% respectively. The histologic grade, stage, age at presentation revealed statistical significance on disease-free survival. All 9 patients treated with extended curettage for grade 1 central chondrosarcomas revealed disease-free survival with excellent functional outcome. CONCLUSION: The disease-free survival rate of chondrosarcomas mainly depended on histologic grade, stage and age at presentation. Local recurrence and distant metastasis also revealed statistically significant differences of disease-free survival rate. Comparing to wide resection, extended curettage for low-grade central chondrosarcomas in extremities were efficient methods with similar survival rate and less functional losses and complications.
Chondrosarcoma ; Curettage ; Disease-Free Survival ; Extremities ; Follow-Up Studies ; Humans ; Neoplasm Metastasis ; Recurrence ; Retrospective Studies ; Survival Rate ; Tumor Burden

PURPOSE: To analyze clinical, radiological and pathological features as well as clinical outcome after surgical treatment of patients with secondary chondrosarcoma arising from osteochondroma(tosis). MATERIALS AND METHODS: We retrospectively reviewed clinical records, radiographs, pathologic slides of 14 patients. Nine patients were male and five were female. The mean age was 34 years. The mean follow-up period was 54 months. RESULTS: All patients had a history of previous mass since childhood or puberty. Preexisted osteochondroma was single in 3 patients and multiple in 10. Remaining 1 patient had multiple osteochondromatosis with enchondromatosis. MRI clearly provided thickness of cartilage cap, which was over 2 cm except in 2 cases. Chondrosarcoma was grade 1 in all except 1 case, which was grade 2. Wide excision was performed in 10 patients, marginal excision in 3 and amputation in 1. Twelve patients were doing very well without evidence of disease. Among 3 patients with marginal excision, 1 patient had local recurrence and 1 patient died of disease. CONCLUSION: Comprehensive understanding of clinical, radiological and pathological features of secondary chondrosarcoma is warranted for accurate diagnosis. The best result can be expected with early recognition of malignant change of osteohcondroma(tosis) and wide excision.
Amputation ; Cartilage ; Chondrosarcoma ; Enchondromatosis ; Female ; Follow-Up Studies ; Humans ; Male ; Osteochondroma ; Osteochondromatosis ; Puberty ; Recurrence ; Retrospective Studies

PURPOSE: To investigate prognostic factors influencing on local recurrence, distant metastasis and event-free survival of liposarcomas. MATERIALS AND METHODS: Fifty-two patients managed for liposarcomas since 1993 were analyzed respectively in the view of prognostic influence of patient age, tumor size, location, histologic type, histologic grade, resection type, surgical margin, chemotherapy and radiation therapy on local recurrence, distant metastasis and event-free survival. The mean follow up period was 39 months. The univariate and multivariate regression analysis were performed for statistical evaluation. RESULTS: The local recurrences occurred in 11 patients (21.2%) and distant metastasis in 4 patients (8%), Event-free survival rate at 4 year follow up was 67%. In univariate analysis, histologic grade, surgical margin, chemotherapy and radiation therapy were significant prognostic factors on local recurrence (p<0.05). However, histologic grade lost its significance in muitivariate analysis. Trunk location revealed higher rate of distant metastasis than extremity location. In univariate analysis on event-free survival. histologic grade and chemotherapy were significant factors (p<0.05). No factor remained significant in multivariate analysis. CONCLUSION: Considering selection bias, positive surgical margin was negative prognostic factor on local recurrence. Liposarcomas arisen in trunk revealed higher rate of distant metastasis. There was no independent prognostic factor on event-free survival of patients with liposarcomas.
Disease-Free Survival ; Extremities ; Follow-Up Studies ; Humans ; Liposarcoma ; Multivariate Analysis ; Neoplasm Metastasis ; Recurrence ; Retrospective Studies ; Selection Bias

Numerous studies have revealed the similarities and discrepancies in two divisions of class II malocclusion, since these malocclusion groups have been postulated to be disparate criterion, much as classified under one diagnostic umbrella. This study was undertaken to describe the craniofacial configurations of class II division 1 and 2, and consequently to discriminate the morphologic differences between the two malocclusion groups in Korean sample. Lateral headfilms of 34 class II division 1 and 29 division 2 were employed, while those of 142 adults of normal occlusion served as a control. The landmarks were digitized and 26 variables were statistically analyzed for one way: 1. There manifested no statistically significant difference in maxillary position anteroposteriorly. Normal occlusion group exhibited most anteriorly positioned mandible, whereas class II division 1 showed the most retroposition. Class II division 1 disclosed clockwise rotation tendency of mandible, which resulted in position of the chin posteriorly. 2. Class II division 1 showed greater in SN to MP, SN to PP significantly than other groups. 3. Class II division 2 showed smaller gonial angle and larger mandibular body length than other groups. 4. Class II division 1 revealed greater anterior lower face height than other groups, whereas division 2 dictated significantly greater posterior face height. 5. Class II division 2 expressed the most retroclined lower incisor, while division 1 manifested the most proclination. The largest interincisal angle resided in Class II division 2 group. There were no significant differences in upper molar position anteroposteriorly.
Adult ; Chin ; Humans ; Incisor ; Malocclusion ; Mandible ; Molar

STUDY DESIGN: A retrospective study. OBJECTIVES: To validate a treatment plan by analyzing the clinical outcome of conservative treatment for patients with osteoporotic vertebral compression fractures at thoracolumbar junctions. SUMMARY OF LITERATURE REVIEW: Osteoporotic vertebral compression fractures, without neurological symptoms, have been treated by conservative management; however, serious sequelae of the osteoporotic vertebral compression fractures have been reported by many investigators. MATERIALS AND METHODS: We evaluated 83 cases; 68 patients had an average age of 71.1 years (58 to 99 years). After conservative treatment of the osteoporotic compression fractures, and based on the clinical outcome derived from a 10-point pain rating scale at last follow up, the group was sub-divided into two groups. Group A (N=28): had a score of above five points on the pain scale. Group B (N=55): had a score of less than five points on the pain scale. Evaluation of the correlation between the clinical outcome and factors affecting outcome such as vertebral body height loss, change in height loss, BMD and bracing were recorded at the initial and follow up assessment. RESULTS: The mean VAS score was 3.20+/-1.62, and the mean compression ratio was 24.74+/-12.03% at injury and 21.68+/-11.43% at the last follow-up. The mean compression ratio at injury was 27.67+/-10.50% in group A and 23.25+/-10.57% in group B. The mean compression ratio at the last follow-up was 53.43+/-13.31% for group A and 42.86+/-13.74% for group B. The change in compression ratio was 25.76+/-12.68% in group A and 19.60+/-10.25% in group B. The mean BMD was -3.63+/-1.16 for group A and -2.80+/-1.10 for group B. The compression ratio at last follow-up, change of compression ratio and BMD were significantly different in comparisons between group A and B (p=0.001, 0.031, 0.003, respectively). CONCLUSION: The clinical outcome of osteoporotic compression fractures was related to the compression ratio, and the compression ratio was related with BMD. Patients with osteoporotic compression fractures with a compression ratio of more than 30% and a T-score from the BMD of less than -3.5 require active treatment.
Body Height ; Braces ; Follow-Up Studies ; Fractures, Compression* ; Humans ; Osteoporosis ; Research Personnel ; Retrospective Studies ; Spine

STUDY DESIGN: This is a retrospective study. OBJECTIVES: We wanted to analyze the radiological features of degenerative lumbar spondylolisthesis and retrolisthesis, and we wanted to verify what radiological factors are related to the development of the retrolisthesis. We also wanted to determine these radiological factors' clinical significance. SUMMARY OF THE LITERATURE REVIEW: There is little information about the pathological mechanism and the clinical and radiological aspects of degenerative lumbar retrolisthsis. MATERIALS & METHODS: Sixty patients were reviewed and divided into three groups. The degenerative lumbar retrolisthesis patients were in group A. The degenerative lumbar spondylolisthesis patients were in group B. Group C patients had no vertebral shift in any direction. The factors we measured were the facet joint angle, the disc height of L3-4, L4-5 and L5-S1, and the lordosis of the lumbar spine. The evaluation of the clinical results was then quantified. RESULTS: The facet joint angle showed no statistical significance between the two groups. The disc height of group A at L4-5 and L5-S1 was more decreased in group A than in group B (p<0.05). Lumbar lordosis was decreased significantly in group A (p<0.05). The preoperative pain was improved at the final follow up, but preoperative pain was significantly higher in group A than in group B (p<0.05). The clinical results were improved in each group, but there was no statistically significant difference between the two groups. CONCLUSIONS: The disc height and lumbar lordosis were considerably reduced in the patients with retrolisthesis, especially compared to those patients with spondylolisthesis. Preoperative pain was higher for the retrolisthesis patients than for the spondylolithesis patients, but there was no significant difference.
Animals ; Follow-Up Studies ; Humans ; Lordosis ; Retrospective Studies ; Spine ; Spondylolisthesis* ; Zygapophyseal Joint

PURPOSE: To investigate and define the clinical results and prognostic factors affecting surgical outcome of the various etiologies of a cervical myelopathy. MATERIALS AND METHODS: Forty-one cervical myelopathy patients, who underwent surgery from March 1997 to March 2004, were retrospectively reviewed. The patients were divided into three groups according to the cause, HIVD (10 cases, group A), OPLL (14 cases, group B), cervical spondylotic myelopathy (17 cases, group C). An anterior cervical discectomy and fusion was carried out on one or two segments in group A, and an expansive open-door laminoplasty was performed in groups B and C. The correlations between age, onset, preoperative JOA score, signal change in the cord on the T2 weighted image MRI, compression ratio, which are known etiologies of myelopathy, and the recovery rate according to causes were analyzed. RESULTS: The mean preoperative and postoperative JOA score was 11.2 and 14.6 respectively. The mean recovery rate was 61.7%. There was no significant difference in the preoperative JOA score in each group (11.40 in group A, 11.93 in group B, 10.53 in group C). The recovery rate was ranked as follows: group A, B, and C (group A 75.98%, group B 61.39%, group C 53.61%) but the difference was not significant. Age, preoperative JOA score, signal change on T2WI MRI in group A (p<0.05), age, preoperative JOA score in group B (p<0.05), age, preoperative JOA score, signal change on T2WI MRI, compression ratio in group C (p<0.05) were significant prognostic factors that influenced the recovery rate. CONCLUSION: There was no difference between the preoperative clinical symptoms and the surgical outcome according to the cause. The most significant prognostic factors affecting the results of surgery for cervical myelopathy were age, preoperative JOA score in each group. A specific prognostic factor in each group may exist, but a further evaluation is needed.
Diskectomy ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; Spinal Cord Diseases*

STUDY DESIGN: This study is a prospective, clinical study for lumbar degenerative kyphosis. PURPOSE: To determine the factors affecting postoperative clinical outcomes in patients who undergo corrective osteotomy for lumbar degenerative kyphosis. OVERVIEW OF LITERATURE: Only a small number of studies have reported clinical results for surgery for lumbar degenerative kyphosis. There are almost no studies about prognostic factors that predict postoperative clinical results. METHODS: This study involved 25 patients who were diagnosed with lumbar degenerative kyphosis and who underwent corrective osteotomy following gait analysis. A pedicle subtraction osteotomy was done at the third lumbar vertebra (L 3). Regarding the fusion level, surgery was done within a range from T10 proximally to S1 distally. Of these, for rigid fixation of a distal part, an iliac screw was used. Pain was evaluated using a 10-point pain scale and a questionnaire about activities. We also evaluated cosmesis and subjective satisfaction using a modified version of the Scoliosis Research Society Outcome-22 (SRS-22) instrument. This assessment was done using a 5-point scale which was designed by us. We assigned patients to group A (good clinical outcomes) if their postoperative pain score was lower than 4 (of 10 points) and if scores indicating activity, cosmesis and subjective satisfaction were higher than 11 (of 15 points). All other patients were assigned to group B (poor clinical outcomes). RESULTS: Clinical outcomes were good in 64% of patients (16/25) and poor in 36% (9/25). Regarding cosmesis and subjective satisfaction, there were significant differences between the two groups. There were also significant differences in physical factors of individual patients such as body mass index (BMI): 23.78 +/- 2.79 in group A and 26.44 +/- 2.75 in group B. On gait analysis, there was a significant difference in the dynamic pelvic tilt: 7.5 +/- 3.3degrees in group A and 11.72 +/- 1.89degrees in group B. CONCLUSIONS: There is no correlation between preoperative degree of kyphotic deformity and clinical outcomes. The degree of anterior rotation of pelvic tilt does not change significantly; rather, compensatory mechanisms of the pelvis and BMI were found to have more influence. Because neither the degree of satisfaction with clinical outcomes nor the increased activity was relatively higher, a more sincere decision should be made before recommending corrective osteotomy for degenerative lumbar kyphosis.
Body Mass Index ; Congenital Abnormalities ; Gait ; Humans ; Kyphosis ; Osteotomy ; Pain, Postoperative ; Pelvis ; Prospective Studies ; Scoliosis ; Spine ; Surveys and Questionnaires

STUDY DESIGN: This is a retrospective study. OBJECTIVES: We analyzed the risk factors and the surgical results for adjacent segment disease after lumbar fusion. SUMMARY OF LITERATURE REVIEW: Many studies have been performed about the risk factors for adjacent segment disease, but the findings are still controversial. MATERIALS AND METHODS: This study was carried out on 35 (13 men, 22 women) of 50 patients who underwent lumbar fusion due to adjacent segment disease with a minimum of 2 year follow-up period from July 1999 to July 2006. The differences of the interval to revision (IR) were statistically analyzed by the examining preexisting degenerative change in the adjacent segments on MRI, the number of fused segments, the lumbar lordosis and the sagittal balance. The surgical outcomes of reoperation were assessed by Brodsky's criteria. RESULTS: Junctional stenosis as adjacent segment disease was seen in 21 cases (60%) and instability was seen in 14 cases (40%), including 2 iatrogenic flat backs and 2 cases of lumbar degenerative kyphosis. The average IR was 93 months for the cases that had less than 2 segment fusion (20 cases) and 62 months in those with more than 3 segment fusion (15 cases). As for lumbar lordosis, 25 cases (71%) had a normal range of angle as well as 101 months until the IR and 10 cases (29%) had an abnormal range of angle as well as 64 months until IR. Six cases were beyond the normal range of sagittal balance (17%) and their average IR value was 59 months. Otherwise, the cases with a normal range of sagittal balance had 109 months for the IR. The clinical outcome was excellent in 6 cases (17%) and good in 15 cases (43%). CONCLUSION: To decrease the adjacent segment disease, we should seriously consider the extent of lumbar fusion and we should restore the angle in lumbar lordosis to the physiological range and the sagittal balance during the initial operation.
Animals ; Constriction, Pathologic ; Ethylenes ; Follow-Up Studies ; Humans ; Kyphosis ; Lordosis ; Male ; Reference Values ; Reoperation ; Retrospective Studies ; Risk Factors