Symptomatic Myelopathy Caused by Ossification of the Yellow Ligament

OBJECTIVE: This study was performed to describe the clinical presentation, surgical outcome in patients with symptomatic myelopathy caused by ossification of the yellow ligament (OYL). METHODS: The authors reviewed consequent 12 patients in whom posterior decompressive laminectomies were performed for OYL from 1999 to 2005. Diagnostic imagings including simple radiographs, computed tomography and magnetic resonance images were performed in each case. The patients were reviewed to evaluate the clinical presentation, surgical outcome and complications of the operation. RESULTS: In all patients, OYL was located in the lower thoracic region and all patients presented with numbness on both limbs and pain. Among them, 5 patients presented with gait disturbance due to paraparesis and two patients had sphincter dysfunction. Decompressive laminectomy through a posterior approach using microscope resulted in improvement of symptoms in all patients, but, recovery was incomplete in a half of the patients. The mean postoperative Japanese orthopaedics association (JOA) score was 7.9 when compared with 4.9 in preoperative assessment and the mean recovery rate was 65%. Dural tear was noticed in four patients, so dural repair was performed, but there were no neurological deficits related to neural injury. CONCLUSION: OYL is an uncommon cause of myelopathy but it can lead to debilitating thoracic myelopathy. Careful decompressive laminectomy can achieve favorable results.

Paraspinal Muscle Sparing Versus Percutaneous Screw Fixation: A Comparative Enzyme Study of Tissue Injury during the Treatment of L4-L5 Spondylolisthesis

OBJECTIVE: Screw fixation via the paraspinal muscle sparing approach and by percutaneous screw fixation are known to diminish the risk of complications, such as, iatrogenic muscle injury as compared with the conventional midline approach. The purpose of this study was to evaluate tissue injury markers after these less traumatic screw fixation techniques for the treatment of L4-L5 spondylolisthesis. METHODS: Twenty-two patients scheduled for posterior lumbar interbody fusion (PLIF) at the L4-L5 segment for spondylolisthesis were prospectively studied. Patients were divided into two groups by screw fixation technique (Group I: paraspinal muscle sparing approach and Group II: percutaneous screw fixation). Levels of serum enzymes representing muscle injury (CK-MM and Troponin C type 2 fast), pro-inflammatory cytokine (IL-8), and anti-inflammatory cytokine (IL-1ra) were analyzed using ELISA techniques on the day of the surgery and 1, 3, and 7 days after the surgery. RESULTS: Serum CK-MM, Troponic C type 2 fast (TNNC2), and IL-1ra levels were significantly elevated in Group I on postoperative day 1 and 3, and returned to preoperative levels on postoperative day 7. No significant intergroup difference was found between IL-8 levels despite higher concentrations in Group I on postoperative day 1 and 3. CONCLUSION: This study shows that percutaneous screw fixation procedure is the preferable minimally invasive technique in terms of minimizing muscle injury associated with L4-L5 spondylolisthesis.

Solitary Lymphoblastic Lymphoma of the Thoracic Spine

Non-Hodgkin's lymphoma rarely originates from bone, and even more infrequently from a vertebral body. Lymphoblastic lymphoma is a rare type of non-Hodgkin's lymphoma, and results from an abnormality in adaptive immune cells. A 27-year-old man presented with a two-month history of night sweats, weight loss, and severe back pain. Radiological studies demonstrated an osteolytic lesion compressing the subarachnoid space at the T11 level. Posterolateral fusion with decompression was performed and a pathologic examination confirmed lymphoblastic lymphoma of the B-cell precursor type. To our knowledge, this is the first report of solitary lymphoblastic lymphoma from B-cell precursors in of the thoracic spine. Herein, we discuss the presenting symptoms and the management of this rare case of lymphoblastic lymphoma.

The Characteristics of Musical Formant and Vocal Fold Vibration in the Classical and Western-Style Singers / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Professional singers have a particular "ringing" sound quality during singing, so called singer's formant. Two types of professional singers in Korea that sound very different are classical (pansori) and western style performers. The purpose of this research was to systematically analyze and compare the acoustic sound structure of both the speaking and singing voices of Korean classical singers (pansori). We also investigated the morphologic and vibratory characteristics of vocal folds using videostroboscopy. MATERIALS AND METHODS: 24 classical singers and 29 western style singers were subjects. The formant frequencies, intensities and singing power ratio was evaluated for clarifying the existence of singing formant. Using laryngeal stroboscopy, the vibratory characteristics were evaluated. RESULTS: The all formant intensities were incraesed in the classical singers, but typical increase of third and fourth formant in the western style singers. The singing power ratio was smaller in the western style singers. Most of classical singers showed abnormal vibratory patterns. CONCLUSION: The western style singers have typical singing formant during singing, but not in the classical singers. Most of classical singers showed abnormal vibratory patterns of vocal folds during phonation, but usually normal vibration in the western style singers.

Two Cases of Intradermal Nevus of the External Auditory Canal / 대한이비인후과학회지

The intradermal nevus is composed of nevus cells which are usually referred to as the melanocytic nevi and is a form of benign cutaneous tumor. Although the intradermal nevi are common benign pigmented skin tumors, their occurrence within the external auditory canal is uncommon. The clinical and pathologic features of the intradermal nevus arising within the external auditory canal are presented, with a review of literature.

Characteristics of Traffic Accident for the Primary School Students and Its Affecting Factors / 예방의학회지

For the purpose to analysis the characteristics of traffic accidents(TA) and investigate the relationship between traffic accidents and children attention problem rating scale(CAP) and, family environment scale(FES), this questionnaire survey was conducted to the 16 primary school students in Taejon from July 14 to August 26, 1997. The number of study subjects who had an experience of traffic accidents from July 1, 1996 to June 30, 1997 were 195, and the number of control subjects were 512. The main results were as follows; 1. The traffic accident rates was 0.9% as a whole, but those were 1.4% in boys, 0.7% in girls, 1.3% in low (1st-3rd) grade, and 0.8% in high (4th-6th) grade. 2. The rates of traffic accidents were high in spring, friday, afternoon and a driveway around home. TA occurred during walking with friends most frequently. 3. In CAP the score of inattention was lower in TA group than control group, and hyperactivity was higher in TA group but they didn't showed significantly different. In FES, cohesion score was higher in TA group than control group, but Conflict score and Expressiveness score were in control group, but they didn't showed significantly different. 4. In CAP the odds ratio of inattention score for TA group was 0.84, but that of hyperactivity score was 1.15. In FES, the odds ratio of cohesion score was 1.06, but that of expression score and conflict score was 0.94 and 0.96, respectively. In conclusion, the relationships between TA and CAP, TA and FES in this study were not clear to explain personal characteristics and environmental conditions.

Immunohistochemical Localization of Insulin-Like Growth Factor-I in the Eustachian Tube of the Rat / 대한이비인후과학회지

Insulin-like growth factor-I(IGF-I) is a peptide hormone of approximately 7.5 kilodaltons which has been shown to be involved in cellular growth and differentiation. Because the IGF-I is synthesized in a variety of tissues, it is thought to act both locally in a paracrine/autocrine manner, as well as a true endocrine hormone after entering the circulation. It may be considered that IGF-I is very important for differentiation of bone, cartilage, and muscle. The eustachian tube has the function of ventilation, clearance, and protection of the middle ear, contributing to the maintenance of normal hearing. After the opening of eustachian tube, it may return to its original position by elasticity resulting from the recoil of elastic fiber, muscle itself, and other deformed soft tissues surrounding the tube. Previously we have studied the distribution of elastic fibers in the rat eustachian tube and ascertained enormous elastin in the cartilage of the eustachian tube. The maintenance of elasticity in the tubal cartilage, related to closing of the eustachian tube, has been suspected as one of important factors in the pathogenesis of otitis media. Rich13) previously described that IGF-I acts as a modulator of the elastogenesis, essential for stretch and recoil actions. However, the examination of the presence of IGF-I in the eustachian tube, especially cartilage may very important as one of factors for well functioning of the eustachian tube. This immunohistochemical study, the tubal cartilage has a considerable content of IGF-I in the capsule around the chondrocytes. The submucosal connective tissue layer of the eustachian tube contained some immunostained cells, considered to be fibroblasts. These findings suggest that IGF-I may be important for normal chondrocyte growth of rat eustachian tube.

Treatment of Inverted Papilloma: A Comparision of Extranasal Operation and Conservative Surgery Using Nasal Endoscope / 대한이비인후과학회지

BACKGROUND: Inverted papilloma is a benign neoplastic lesion which shows high recurrence rate and possibility of association with malignancy. Medial maxillectomy has been preferred as a treatment of choice, for conservative treatments resulted in higher recurrence rate. However, introduction of nasal endoscope made more precise evaluation of intranasal lesion under brighter illumination. OBJECTIVES: Aim of this study was to compare the recurence rate between medial maxillectomy and conservative surgery using nasal endoscope. MATERIAL AND METHODS: Thirty one patients who underwent operation between 1980 and 1995 were retrospectively studied. RESULTS: Fifteen patients were treated via external approach and sixteen patients endoscopically. Inverted papilloma was recurred in two cases of endoscopic surgery group and one case of external surgery group. CONCLUSION: Endoscopic conservative surgery can be an alternative surgical modality in the selected cases.

Clinical Characteristics of Intracordal Cysts / 대한이비인후과학회지

The intracordal cysts are more increasingly diagnosed and treated due to advanced laryngeal microsurgical technique. The intracodal cysts are classified into two categories as the content of the cysts and lining epithelium. The one is the ductal cysts, known as mucous retension cysts, resulting from retension of mucous in dilated collecting ducts due to ductal obstruction, and can be found anywhere in the larynx. The another is the epidermoid cysts, containing accumulated keratin. It results either from a rest of epithelial cells buried congenitally in the subepithelial layer or from healing of the mucosa injured by voice abuse over buried epithelial cells. In the present series, 44 cases of the intracordal cysts treated with laryngeal microsurgeries from 1988 to 1995 are reported. In the clinical evaluation, the ductal cysts are considered more frequent than the epidermoid cysts. With indirect laryngoscopic examination, the ductal cysts can be frequently misdiagnosed as vocal polyps or Reinke's edema, but the epidermoid cysts are relative easily dignosed. The etiologic factor of intracordal cysts are suspected as voice abuse and upper respiratory infection. Pathologically, the ductal cysts are lined with mucosal epithelium, but the epidermoid cyst are lined with squamous epithelium.

Changes of Renal Cadmium Accumulation Levels and Urinary Cadmium Excretion Levels Induced by Long-term Cadmium Exposure in Rats / 대한산업의학회지

This study was performed to compare the cadmium accumulation levels in kidney with urinary cadmium excretion levels according to the duration of cadmium exposure in rats. Total 120 male rats, 6 weeks of age, were administered 0.5 mg/day of Cd to subcutaneously, intraperitoneally and orally 6 times per week for 12 weeks. The animals were sacrificed in the 1st day of 2nd, 4th, 6th, 8th, 10th and 12th week after beginning of cadmium administrations. Body weight, hematologic values, enzyme activities, renal Cd levels, urinary Cd and proteins were calculated and each value was compared according to the Cd administration routers. The Cd accumulation levels in the kidney of rats increased remarkably for 6-8th weeks which were experimented and urinary Cd excretion levels and urinary protein levels showed the tendency of increasing with the Cd accumulations in kidneys, especially in the subcutaneous injected rats. On the other hand, there was a significant positive correlation among the total Cd administration, the Cd accumulation in the kidneys, the urinary Cd excretion and protein.

A study on the development of low back pain and the risk factors of manufacturing workers / 예방의학회지

This study was conducted to investigate the prevalence rate of low back pain during past one year and its risk factors. The data were collected form 1,384 manafacturing factory workers from March 1, 1992 to August 30, 1992. The results obtained were as follows: 1. The one year prevalence rate of low back pain by manufacturing company was 38.4% in textile manufacturing, 35.2% in concrete reenforcement, 31.0% in cigarette and 26.1% in metal part(P<0.01). 2. In textile manufacturing, age groups with high prevalence rate of low back pain were 30's (36.8%) and 40's (36.4%) (P<0.05), and the one year prevalence rates of low back pain by marital state were 34.9% in married workers and 28.5% in unmarried(P=0.0511). 3. The one year prevelence rates of low back pain by job part are 35.0% in labor workers and 26.1% in clerical(P<0.05), and by work hour per day it was 34.9% in 9 or more and 28.9% in 8 or less (P<0.05). 4. The highest group of low back pain by work posture was 43.5% in 'lifting and transfering materials', and it by fitness of chair was 56.0% in uncomfortable one, and by height of working board was 33.6% in low working one. 5. In logistic regression analysis, significant determinants with low back pain were marital state (P<0.05), work hour per day(P<0.05), height of working board(P<0.01), and work posture(P<0.01).

A Study On The Factors Of Absenteeism Among The Manufacturing Workers / 예방의학회지

This study was to examine the actual conditions and contributing factors of absenteeism in manufacturing workers. Subjects were 1,184 workers employed in Taejon city and the observation period for absenteeism was 3 months (June to August), 1992. We obtained the following results. 1. Percentage of the absentees among the studied subjects were 21.1% in gross absence and 6.9% in sickness absence. Gross absence rate of subjects was 1.2% and sickness absence rate was 0.5%. 2. In the group of absentees, mean days of absence was 2.8 days and those of sickness was 4.4 days. Mean days of sickness absence due to injury was higher than that of illness, but the total days of sickness absence was high in extremity injuries, trunk injury, general fatigue, head injury, musculoskeletal problem in that order. 3. Variables contributing to the absence were job classification, education level, working hours per day, exposure of noxious factor, worker classification. 4. In the group of absentees, variables influencing the gross absence rate were working atmosphere, body mass index, working environment, working hours per day but those of the sickness absence were working hours per day, education level and working atmosphere.