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1.
Clinics in Orthopedic Surgery ; : 299-306, 2018.
Article in English | WPRIM | ID: wpr-717126

ABSTRACT

BACKGROUND: Although satisfactory mid- to long-term results of rotational acetabular osteotomy for early osteoarthritis secondary to acetabular dysplasia have been reported, there is still controversy about the long-term effects of this surgery in more advanced osteoarthritis. The purpose of this study was to investigate the radiographic progression of osteoarthritic changes after rotational acetabular osteotomy in acetabular dysplasia according to the preoperative Tönnis grade and evaluate its effects after minimum 10-year follow-up. METHODS: We performed 71 consecutive rotational acetabular osteotomies in 64 patients with symptomatic acetabular dysplasia between November 1984 and April 2005. Of these, 46 hips (four hips with Tönnis grade 0, 30 with grade 1, and 12 with grade 2) whose clinical and radiographic findings were available after minimum 10-year follow-up were evaluated in this study. The mean age at the time of surgery was 39.0 years (range, 18 to 62 years) and the average follow-up duration was 17.3 years (range, 10.0 to 27.7 years). Clinical and radiographic evaluations were performed according to the preoperative Tönnis grade. RESULTS: The average Harris hip score improved from 71.8 (range, 58 to 89) to 85.1 (range, 62 to 98). The radiographic parameters also improved in all Tönnis grades after the index surgery. Although the improvement of radiographic parameters was not different between preoperative Tönnis grades, the incidence of osteoarthritic progression was significantly different between grades (zero in Tönnis grade 0, four in Tönnis grade 1, and 10 in Tönnis grade 2; p < 0.001). The mean age at the time of surgery was also significantly older in osteoarthritic progression patients (p < 0.002). Kaplan-Meier survivorship analysis, with radiographic progression of osteoarthritis as the endpoint, predicted a 10-year survival rate of 100% in Tönnis grade 0, 85.7% in Tönnis grade 1, and 14.3% in Tönnis grade 2 (p < 0.001). CONCLUSIONS: The outcome of rotational acetabular osteotomy in most hips with Tönnis grade 0 and 1 was satisfactory after an average of 17 years of follow-up. The incidence of osteoarthritic progression was higher in Tönnis grade 2 and older age. Our results support that early joint preserving procedure is essential in the case of symptomatic dysplastic hips.


Subject(s)
Humans , Acetabulum , Follow-Up Studies , Hip , Incidence , Joints , Osteoarthritis , Osteotomy , Survival Rate
2.
Hip & Pelvis ; : 165-185, 2012.
Article in Korean | WPRIM | ID: wpr-221116

ABSTRACT

No abstract available.

3.
Safety and Health at Work ; : 34-38, 2011.
Article in English | WPRIM | ID: wpr-169141

ABSTRACT

OBJECTIVES: The antimicrobial activity of silver nanoparticles has resulted in their widespread use in many consumer products. Yet, despite their many advantages, it is also important to determine whether silver nanoparticles may represent a hazard to the environment and human health. METHODS: Thus, to evaluate the genotoxic potential of silver nanoparticles, in vivo genotoxicity testing (OECD 474, in vivo micronuclei test) was conducted after exposing male and female Sprague-Dawley rats to silver nanoparticles by inhalation for 90 days according to OECD test guideline 413 (Subchronic Inhalation Toxicity: 90 Day Study) with a good laboratory practice system. The rats were exposed to silver nanoparticles (18 nm diameter) at concentrations of 0.7 x 10(6) particles/cm3 (low dose), 1.4 x 10(6) particles/cm3 (middle dose), and 2.9 x 10(6) particles/cm3 (high dose) for 6 hr/day in an inhalation chamber for 90 days. The rats were killed 24 hr after the last administration, then the femurs were removed and the bone marrow collected and evaluated for micronucleus induction. RESULTS: There were no statistically significant differences in the micronucleated polychromatic erythrocytes or in the ratio of polychromatic erythrocytes among the total erythrocytes after silver nanoparticle exposure when compared with the control. CONCLUSION: The present results suggest that exposure to silver nanoparticles by inhalation for 90 days does not induce genetic toxicity in male and female rat bone marrow in vivo.


Subject(s)
Animals , Female , Humans , Male , Rats , Bone Marrow , Erythrocytes , Femur , Inhalation , Inhalation Exposure , Mutagenicity Tests , Nanoparticles , Rats, Sprague-Dawley , Silver
4.
Korean Journal of Orthodontics ; : 467-473, 2000.
Article in Korean | WPRIM | ID: wpr-649471

ABSTRACT

system may include bending force in first and second orders and a torsional force in third order. Analytical and experimental studies on bending force have been introduced, but information about torsion is still lack. The purpose of this study was to estimate the torsional moment in the force system of rectangular arch wires through theoretical and experimental studies. Wires most frequently used for third order control were selected as study materials. Cross sections of 0.016X17.022, 0.0174.025, 0.0194.025 inch rectangular wires in four different materials such as stainless steel (O mco), TMA (Ormco), NiTi (Ormco), and braided stainless steel (DentaFlex, Dentaurum) were used. The torque/twist rate of each test material was calculated using the torsion fotiuula Torque/twist rate, yield torsional moment, and ultimate torsional moment were measured with a torque gauge. The torsion formula assesses that the torque,/twist rate (T/theta) is proportional to the characteristics of material(G) and cross section (J), and is inversely proportional to the length of wire (L). Most experimental results conesponded with the formula. The relative stiffness was calculated for reference to a logical sequence of wire changes.


Subject(s)
Logic , Orthodontic Wires , Stainless Steel , Torque , Torsion, Mechanical
5.
Korean Journal of Orthodontics ; : 185-196, 2000.
Article in Korean | WPRIM | ID: wpr-647630

ABSTRACT

Patients who want to reduce their lip protrusion usually estimate the severity of the lip protrusion on the frontal aspect. Most orthodontists have a perplexed experience of a reduced thin line of vermilion border on the frontal aspect as incisors are retreated, even though the lip protrusion is thought to be reduced favorably on the sagittal aspect. Some patients, also look older after orthodontic treatment because of severe lip thinning. This unaesthetic reduction of vermilion border urges us to study the vertical lip change during orthodontic procedure. The purpose of this study was to evaluate the vertical lip and perioral soft tissue changes in respect to incisor retraction in an effort to analyze which factors might be responsible for their vertical changes, using the multiple regression analysis. The results were as follows. 1. Upper and lower lip philtrum length(SnLs, LiB') were increased after retraction of anterior teeth, were as upper and lower vermilion height(LsStms, StmiLi), and vermilion length(LsLi) were decreased. 2. Upper and lower lip length(SnStms, StmiB'), and soft tissue lower anterior facial height(SnMe') did not show any significant difference after treatment. 3. The increase of the upper lip philtrum length was mainly influenced by the extrusion of upper anterior teeth(U1V), and the increase of the lower lip philtrum length was mainly influenced by the initial overjet before treatment. 4. The decrease of the upper and lower lip vermilion height was mainly influenced by the decrease of upper lip thickness.


Subject(s)
Humans , Incisor , Lip , Tooth
6.
The Journal of the Korean Orthopaedic Association ; : 877-882, 1999.
Article in Korean | WPRIM | ID: wpr-651725

ABSTRACT

PURPOSE: To establish the incidence of deep vein thrombosis among Koreans after primary total hip arthroplasty and the usefulness of color doppler ultrasonography for routine noninvasive screening for deep vein thrombosis. MATERIALS AND METHODS: We performed prospective, randomized routine venography and color doppler ultrasonography before and after operation in a consecutive series of 89 primary total hip arthroplasty in which no form of prophylaxis was used. RESULTS: Of the 89 cases, eleven (12.4%) were found to have deep vein thrombosis (three proximal veins and eight distal veins) by bilateral venography. Most of the thromboses except two were asymptomatic. No patient had a symptomatic pulmonary embolism. Statistical analysis of risk factors, age, gender, weight, height, fixation method, and duration of operation time, were performed and there was no statistical difference (P>0.05). The reliability of color doppler ultrasonography for detection of deep vein thrombosis was demonstrated. CONCLUSIONS: We found insufficient evidence to recommend routine thromboprophylaxis in primary total hip arthroplasty among Koreans. The authors recommend that routine bilateral color doppler ultrasonography screening be considered after primary total hip arthroplasty for detection of deep vein thrombosis


Subject(s)
Humans , Arthroplasty, Replacement, Hip , Incidence , Mass Screening , Phlebography , Prevalence , Prospective Studies , Pulmonary Embolism , Risk Factors , Thrombosis , Ultrasonography, Doppler, Color , Veins , Venous Thrombosis
7.
The Journal of the Korean Orthopaedic Association ; : 559-564, 1999.
Article in Korean | WPRIM | ID: wpr-647529

ABSTRACT

PURPOSE: To evaluate the effect of curettage and autogenous bone graft procedure in treating early stage (I, lla) osteonecrosis of the femoral head. MATERIALS AND METHODS: The series included 25 cases in 22 patients, having at least 1-year follow up and 8 years at the most. The operative technique was a modified method based on Steinberg's procedure. RESULTS: In the postop clinical evaluations, 66.7% of stage I, and 61.5% of stage II a were graded as "good" In the radiological evaluation, 66.7% of stage I, and 53.8% of staged II a were grad ed as "good". The number of patients needed for total hip replacement were 4 cases (16%). CONCLUSIONS: Curettage and autogenous bone graft procedure is effective in treating the femoral head.


Subject(s)
Humans , Arthroplasty, Replacement, Hip , Curettage , Follow-Up Studies , Head , Necrosis , Osteonecrosis , Transplants
8.
Korean Journal of Orthodontics ; : 991-999, 1998.
Article in English | WPRIM | ID: wpr-656189

ABSTRACT

Tooth impact on may lead to malocclusion, root resorption, cyst or aberrant changes in adjacent teeth Clinical and radiographic examinations are used to locate the impaction, and appropriate treatment plans must be made to relocate the impacted tooth. When surgically exposing the impacted tooth, periodontal considerations to conserve maximum amount of soft and hard tissue are used Oral hygiene instructions are emphasized to maintain sound periodontal health. Securing enough space for .the impacted tooth and proper anchorage is important. Proper use of force and mechanics is crucial to prevent such complications as root resorption. Various patterns of orthodontic traction may be employed as situation permits. Most impaction cases can be managed with orthodontic traction to restore function and esthetics, provided that early detection and proper diagnosis and treatment planning are made.


Subject(s)
Diagnosis , Esthetics , Malocclusion , Mechanics , Oral Hygiene , Root Resorption , Tooth , Tooth, Impacted , Traction
9.
The Journal of the Korean Orthopaedic Association ; : 29-32, 1998.
Article in Korean | WPRIM | ID: wpr-655214

ABSTRACT

In 1970, Boutine introduced a alumina ceramic for cemented total hip replacement . A ceramic articulation thought to be superior to metal on polyethylene due to its extremely low coefficient of friction and its potential for resistance to wear. Mechanical failure of ceramic femoral head is rare. We report a case of fracture of ceramic femoral head, which occured after implantation of uncemented total hip replacement.


Subject(s)
Aluminum Oxide , Arthroplasty, Replacement, Hip , Ceramics , Friction , Head , Polyethylene
10.
The Journal of the Korean Orthopaedic Association ; : 1623-1629, 1997.
Article in Korean | WPRIM | ID: wpr-644614

ABSTRACT

There has been considerable controversies in the method of the treatment of dislocation of the acromioclavicular joint, especially in grade III injury. It is hard to give a direct firm repair having a short ruptured coracoclavicular ligament. Thats why there are lots of difficulties in the treatment. Therefore, in operative treatment, the authors make use of cotton tape on coracoid process and clavicle as a reconstructive technique, because we have thought a simple fixation of acromioclavicular joint adding to a firm fixation of clavicle and coracoid process is inevitable. From January 1991 to December 1995, twenty-nine cases of grade III acromio-clavicular dislocation were treated by the modified Phemister method with using the cotton tape. Twenty-four patients were followed for an average of fifteen months and the following results were obtained. 1. The clinical results were evaluated by Weitzman criteria after average fifteen months follow up. An excellent result was obtained in 19 cases (79.2%), a good result in 3 cases (12.5%) and a fair result in 2 cases (8.3%), consecutively. 2. Clinical result in patients over 60-year old were bad. 3. The comparison of the coracoclavicular interval ratio before surgery with that after surgery facilitated the evaluation of effectiveness of the coracoclavicular ligament reconstruction. 4. The operative technique is through temporary fixation using K-wires which endows horizontal stability, and it fixes clavicle and coracoid process using cotton tape which endows vertical stability.


Subject(s)
Humans , Middle Aged , Acromioclavicular Joint , Clavicle , Joint Dislocations , Follow-Up Studies , Ligaments
11.
The Journal of the Korean Orthopaedic Association ; : 1610-1617, 1995.
Article in Korean | WPRIM | ID: wpr-769829

ABSTRACT

Total hip replacement for adults with severe acetabular dysplasia presents a difficult problem because deficient bone stock and soft tissue contractures usually prevent sitting at the normal anatomic level. The rationales of high hip center are due to high failure rate of bulk structural weight bearing graft, good short-term result of hemispherical cementless acetabular component in revision surgery, high hip center but not lateral which does not adversely affect the biomechanics of the hip, and intimate apposition with viable host bone. We represented the short-term results of 21 total hip replacements with proximal placement of the acetabular cup than the anatomical position that is normally used. The mean duration of follow up was 18 months(range, 12-58 months) and the mean age of the patient was fifty-one years(range, thirty to sixty-seven years). Most of these hips had a major deficiency or defect of the acetabular bone stock. They had an aver- age Harris hip score of 47 points preoperatively and 90 points postoperatively. Roentgenographic measurements showed that the mean change in the height of the center of the hip postoperatively was only +6.6 millimeters and the mean change of horizontal location of them was 10 millimeters medial to the preoperative position. Postoperative complications included calcar fracture(1 case), trochanteric bursitis(1 case), postop- erative dislocation(1 case) and one case of radiological loosening of the acetabular component. The center of the hip in THR is not a crucial parameter with regard to the long-term stability of acetabular component, so our recommendation is to place the acetabular component at a more proximal but not lateral position if strong bone stock is available. But future studies of high hip center need to address femoral component longevity.


Subject(s)
Adult , Humans , Acetabulum , Arthroplasty, Replacement, Hip , Contracture , Femur , Follow-Up Studies , Hip Joint , Hip , Longevity , Osteoarthritis , Postoperative Complications , Transplants , Weight-Bearing
12.
The Journal of the Korean Orthopaedic Association ; : 1080-1085, 1994.
Article in Korean | WPRIM | ID: wpr-769451

ABSTRACT

False aneurysm has been recognized for many years. Incomplete severance of an artery as the result of trauma is thought to be the precipitating factors in the formation of false aneurysm. False aneurysm of the peripheral artery is presented with pulsating mass and may show extrinsic indentations of the adjacent bone with or without neurovascular symptoms, mimicking a malignant tumor. But careful history taking can reveal a proceeding deep penetrating injury variable period prior to development of symptoms. We are reporting two cases of false aneurysm of the superior gluteal artery and superficial femoral artery in each after trauma.


Subject(s)
Aneurysm, False , Arteries , Femoral Artery , Precipitating Factors
13.
The Journal of the Korean Orthopaedic Association ; : 1866-1873, 1993.
Article in Korean | WPRIM | ID: wpr-651185

ABSTRACT

No abstract available.


Subject(s)
Animals , Rats , Corrosion Casting , Corrosion , Head
14.
The Journal of the Korean Orthopaedic Association ; : 774-780, 1993.
Article in Korean | WPRIM | ID: wpr-649977

ABSTRACT

No abstract available.


Subject(s)
Child , Humans , Humerus
15.
The Journal of the Korean Orthopaedic Association ; : 527-539, 1993.
Article in Korean | WPRIM | ID: wpr-649889

ABSTRACT

No abstract available.


Subject(s)
Head , Magnetic Resonance Imaging , Osteonecrosis
16.
The Journal of the Korean Orthopaedic Association ; : 276-290, 1993.
Article in Korean | WPRIM | ID: wpr-645730

ABSTRACT

No abstract available.

17.
The Journal of the Korean Orthopaedic Association ; : 186-192, 1993.
Article in Korean | WPRIM | ID: wpr-645694

ABSTRACT

No abstract available.

18.
Journal of the Korean Radiological Society ; : 261-268, 1992.
Article in Korean | WPRIM | ID: wpr-51648

ABSTRACT

To explore the ability of magnetic resonance imaging(MRI) in the diagnosis of avascular necrosis(AVN) of the femoral head, we compared appearances on MRI of 85 proven AVN lesions with those on radiographs(n=79)and radionuclide scans(n=75). Clinical symptoms(n=85) were also correlated. All MR studies included coronal and axial T1WI and coronal T2WI. All lesions involved the anterosuperior aspect of the femoral head and were surrounded by a low signal intensity rim of both T1 and T2WI. The signal intensity of the lesions was variable depending on the disease course, and lesions were divided into four classes according to the classification suggested by Mitchell. Radiogrphs were normal in 16%(13/79) of the lesions which were in MR class A(10), B(1), C(2). The radionuclide scans showed normal in 16%(12/75) of the lesions which were in MR class A(8), B(1), C(2), D(1). On the other hand. 93% of the lesions with MR class A(27/29) showed stage 1 and 2 lesions on radiographs. Clinical symptoms were absent in 25%(21/85) of the leions, and among these. 81%(17/21) were MR class A. Conclusively. MR is superior to the radiograph and radionuclide scan in the early detection of AVN, and can also show the exact location, extent and signal chasacteristics of the lesion. Therefore, MR is essential in diagnosis and management of AVN.


Subject(s)
Classification , Diagnosis , Hand , Head , Magnetic Resonance Imaging , Necrosis
19.
The Journal of the Korean Orthopaedic Association ; : 1630-1639, 1992.
Article in Korean | WPRIM | ID: wpr-646901

ABSTRACT

No abstract available.

20.
The Journal of the Korean Orthopaedic Association ; : 1570-1578, 1992.
Article in Korean | WPRIM | ID: wpr-652199

ABSTRACT

No abstract available.


Subject(s)
Arthroplasty, Replacement, Hip
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