Bone is a heterogenous and anisotrophic material exhibiting elastic, viscoelastis and plasticproperties. A considerable amount of information is now available regarding biomechanical properties and mechanisms of fractures of mature long bones, but less is known about the properties of the growing bones. In order to assess the biomechanical properties under tension, rabbits growing bones were loaded with Instron Modal 1,000 until fracture occurred. Two hundred tibiae of 100 New Zealand white immature rabbits were divided into 6 experimental groups according to maturity and size. Group I-R(40 right tibiae of 1-month old rabbits), Group I-L (40 left tibiae of 1-month old rabbits), Group II-R(20 right tibiae of 3-month old rabbits), Group II-L (20 left tibiae of 3-month old rabbits), Group III-R(40 rigth tibiae of 5-month old rabbits), and Group III-L(40 left tibiae of 5-month old rabbits). The following results were obtained. 1. Fracture type was transverse.or nearly transverse in 170 out of the total 200 tibiae(85%).
Absorption ; Elastic Modulus ; New Zealand ; Rabbits ; Tensile Strength ; Tibia

In order to compare the efficacies of some surgical procedures for correction of congenital muscular tortiollis, we evaluate 36 patients who had been treated either by unipolar release (19 patients) or bipolar release (17 patients) of the sternocleidomastoid (SCM) muscle at Seoul National University Children Hospital from August 1985 to June 1993. The average follow up period was 4.1 years (range, 1 year to 7 years and 8 months). The average ages at the time of operation was 3.4 years (range, 11 months to 7 years and 1 month) in the unipolar group and 9.7 years(range, 4 years and 5 months to 16 years and 11 months) in the bipolar group. Postoperatively, flexion and extension range of motion of the neck was not limited of limited less than 10 degrees, if present, in all cases. In rotation motion, 89.4% of the unipolar group and 94.1% of the bipolar group showed no limitation or limitation of less than 10 degrees when compared to the normal side postoperatively. In lateral bending, however, 21.1% of the unipolar group and 21.5% of the bipolar group showed limitation of more than 10 degrees when compared to the normal side postoperatively. Facial asymmetry, which was present in 89.4% of the unipolar group and all cases of bipolar group preoperatively, disappeared in 73.7% of the unipolar group and 23.5% of the bipolar group and improved in 94.1% of the unipolar group and 64.7% of the bipolar group. The over-all functional and cosmetic results were assessed according to the modified Ling's criteria. In function results, 14 patients(73.3%) had excellent or good results in unipolar group and 12 patients(70.6%) in bipolar group. In cosmetic results, 15 patients(78.9%) had excellent or good results in unipolar group and 11 patients(64.7%) in bipolar group. Recurrence rate was higher in the unipolar group (15.8%) than in the bipolar group (5.8%). In conclusion, limitation of lateral bending was more resistant to the treatment than the limitation of rotation. Bipolar release of SCM muscle would be recommendable even in young children in terms of recurecce.
Child ; Facial Asymmetry ; Follow-Up Studies ; Humans ; Neck ; Range of Motion, Articular ; Recurrence ; Seoul ; Torticollis

It is essential to define the mechanical and morphological characteristics of bone in undrestanding the mechanism and treatment of fractrues of bone. We already reported the results of bending study in 1983 and tension study in 1987 to assess the mechanical and morphological changes of bone according to the growth. Following these studies, we performed torsion study on growing long bone to have better understanding of the characteristics of bone. In order to assess the mechanical and morphological properties of fracture of growing bone by torsion, we divided 100 Newzealand white rabbits(40 1-month-old rabbits, 20 3-months old rabbits and 40 5-months-old rabbits) into 6 experimental groups according to their maturity and side : Group 1(right femur of 1 month old), Group 2( left femur of 1 month old), Group 3(right femur of 3 months old), Group 4(left femur of 3 months old), Group 5(right femur of 5 months old), Group 6(left femur of 5 months old). Each group of femora were loaded in torsion with varing distance and the following results were obtained: 1. Fracture shapes were composed of the spiral component and the vertical component which connected the two ends of the spiral component. 2. Younger bones revealed greater deformation angle and apex angle but less obliquity than older bones. 3. When the gap between the grips were lengthened three times, there was a very signi ficant increase of deformation angle and obliquity but apex angle was decreased and the fracture angle showed little change. 4. It was necessary to measure the apex angle and obliquity in the morphological description of fractures by torsion. 5. We observed when a certain degree of angular deformity was applied on a bone at a certain age, the fracture was occured through the tension failure regardless of types of loading forces.
Congenital Abnormalities ; Femur ; Hand Strength ; Humans ; Infant, Newborn ; Rabbits

No abstract available.
Cerebral Palsy* ; Muscle Spasticity*

Photoplethysmography(PPG) employs an infrared light-emitting diode to transmit light into the skin noninvasively. Light reflected from blood cells is received by a photocell or phototrotransistor which permits recording of the pulsatile cutaneous microcirculation. The use of PPG for vascular measurements in extremities is not new. Since Hertzmann, in 1938, first described the technique to measure skin blood flow, a few investigators have used PPG for clinical application. However, experimental reports on the photoplethysmographic assessment of blood flow after arterial reanastomosis are rare. We assessed the changes of blood flow after reanastomosis of the femoral artery in rabbits using photoplethysmography. We divided 20 rabbits into 3 experimental groups. In Group I, the femoral artery was surgically exposed and clamped for 60 minutes. In Group II, the femoral artery was surgically exposed and clamped, as in Group I, and then severed and anastomosed crudely in order to creat thrombus formation. In Group IU, the femoral artery was prepared as Group II and then anastomosed carefully to ensure patency. Blood flow was measured by photoplethysmography on the anteromedial aspect of the right hind leg, every 15 minutes for the fisrt 2 hours, at the 3rd day, I week, and II weeks post-operatively. The following results were obtained l. After the removal of vascular clamp, the mean time for the pulse wave to return to normal form was 63±24.0 minutes in Group I and 63±18.7 minutes in Group III. There was no statistically significant difference beween the two groups. When the wave form was normalized, it remained so continuously. 2. After the removal of vascular clamp, the mean time for the wave amplitude to return to normal was 108±11.2 minutes in Group I and 102±16.4 minutes in Group III. There was no statistically significant difference between the two groups. 3. The thrombosis which obstructed blood flow was formed within the first 60 minutes(mean time: 49±12.4 minutes) in all the animals in Group II. When the thrombosis was formed, it was readily detected by the change of wave form and by decrease in amplitude. 4. It is concluded from this experiments the changes of blood flow after reanastomosis of the femoral artery in rabbits were accurately assessed by PPG. It is suggested that PPG can be used clinically in monitoring blood flow after arterial reanastomosis.
Animals ; Blood Cells ; Extremities ; Femoral Artery ; Humans ; Leg ; Microcirculation ; Photoplethysmography ; Rabbits ; Research Personnel ; Skin ; Thrombosis

We carried out animal experiment in order to determine the effect of resection of nerves, muscles and tendons on the induction of osteoporosis. One hundred and forty rats, weighing approximately 250 gm, were divided into seven groups. In Group I, as a control group, the three skin incisions, one on the anterior aspect of the knee, one on the anteromedial aspect of proximal thigh, and one on the posterior aspect of proximal thigh were made and wounds were sutured. In Group II, the patellar tendon and the extensor digitorum longus tendon were divided to disable knee extension. In Group III, all the knee flexors were divided. In Group IV, all the knee extensors and flexors were divided. In Group V, the femoral nerve was divided to disable knee extension. In Group VI, the sciatic and obturator nerves were divided to diable knee flexion. In Group VII, the sciatic, and obtrator nerves were all divided. Before the procedures, bone density was measured by photon absorptiometry and postoperatively, the measurement was repeated every two weeks until the eighth week. At the time of each measurement, two rats were sacrificed out of each group and were submitted to microphotographic measurement of the tibial cortices. The results were as follows. l. In the muscle and tendon resection groups (Group II, Group III, Group IV), the bone density significantly decreased two weeks after operation and then, gradually increased four, six and eight weeks. 2. In the nerve resection groups (Group V, Group VI, and Group VII), the bone density decreased significantly two and four weeks after operation and then gradually increased six, and eight weeks after operation. 3. In both motor resection and denervation, the paralysis of both flexors and extensors of the knee, caused more decrease in bone density than the paralysis of either flexor or extensor. 4. In the muscle and tendon resection groups, the bone density was significantly more decrease two weeks after operation when the flexors were resected, but thereafter there was no significant difference between the flexors and extensors resection. In the nerve resection group, the paralysis of knee flexors caused more decrease in bone density than the paralysis of knee extensors throughout the entire experimental period. 5. The nerve resection groups demonstrated significantly more severe loss of bone density than muscle and tendon resection groups throughout the entire experimental period. 6. The values of bone density measured by photon absorptiometry correlated well with the cortical thickness indices. Bssed upon these observations, we came to the following conclusions. 1. The osteoporosis following injuries of the nerve, muscle, and tendon is most significant at two weeks after injury. 2. Denervation causes more severe osteoporosis than muscle and tendon injuries. 3. It is suggested that the photon absorptiometry is a reliable means in the evaluation of the osteoporosis.
Absorptiometry, Photon ; Animal Experimentation ; Animals ; Bone Density ; Denervation ; Femoral Nerve ; Knee ; Muscles ; Obturator Nerve ; Osteoporosis ; Paralysis ; Patellar Ligament ; Rats ; Skin ; Tendon Injuries ; Tendons ; Thigh ; Tibia ; Wounds and Injuries

We investigated the effect of tibial lengthening by means of callotasis on enchondral growth of the tibia, Ninety-nine 5-week-old immature rabbits were separated into five groups according to the percentage of lengthening : GroupI(10% lengthening), Group II (20% lengthening), Group III (30% lengthening), Group IV (40% lengthening), Group V (sham operation without lengthening). Osteotomy of the tibia and fibula was made at the proximal metaphysiodiaphyseal junction. Distraction was started at the rate of 0.25mm twice a day from the third postoperative day to simulate the currently accepted callotasis. In Group I, II, and V, there two were no statistically significant differences in the growth rates between the left operated and the right normal tibiae. In contrast, the ratios of left over right tibial length decreased significantly in Group III (4.8%), and Group IV (8.6%) at the completion of lengthening(p < 0.0001), and remained decreased until near skeletal maturity. Histomorphometric study revealed that, in Group III and IV, there were statistically significant decreases in the ratios of the thickness of left over night tibiae at both proximal and distal growth plate(p < 0.0001). Immunohistochemical study also revealed that, in Group III and Group IV, the ratios of left over right bromodeoxyuridine(BrdUrd) labeling percentage decreased significantly (p < 0.0001). In summary, when the tiba was lengthened 30% or more, retardation of enchondral growth was evident, which persisted from the time of completion of lengthening to near skeletal maturity. It is postulated that unphysiologically increased pressure on the growth plate due to excessive bone lengthening may be closely related with the inhibition of enchondral growth.
Bone Lengthening ; Fibula ; Growth Plate ; Osteogenesis, Distraction ; Osteotomy ; Rabbits ; Tibia

No abstract available.
Congenital Abnormalities* ; Ilizarov Technique* ; Upper Extremity*

PURPOSE: To report polymicrobial keratitis involving Pseudomonas aeruginosa, Acinetobacter baumannii, and Ochrobactrum anthropi. CASE SUMMARY: A 53-year-old female complained of pain and secretion in her right eye, which started 6 weeks before her visit. She applied steroid ointment, which was received from the dermatologist, to her eyelid 7 days prior to her visit but this treatment worsened her symptoms. At the initial visit, the visual acuity of the right eye was light perception, and purulent secretions were observed. Using a slit lamp, severe conjunctival hyperemia, hypopyon, and a ring-shaped central corneal ulcer were observed. The anterior chamber and fundus were not observed due to corneal lesions but ultrasonography showed no intraocular inflammation. Infectious keratitis was suspected and cultured by corneal scraping. During the incubation period, 0.5% moxifloxacin, 2% voriconazole, and 1% cyclopentolate were administered. A total of 400 mg of moxifloxacin and 100 mg of doxycycline were given orally. In the primary culture, Pseudomonas aeruginosa and Acinetobacter baumannii were identified so 5% ceftazidime, which was sensitive for the antibiotic susceptibility results was further instilled. Thereafter, the keratitis improved but the keratitis again worsened while maintaining the topical treatment. A secondary culture was positive for Ochrobactrum anthropi. Treatment with 1.4% gentamicin, which was sensitive for the antibiotic susceptibility test was added and the keratitis improved. A conjunctival flap was performed because of the increased risk of perforation. CONCLUSIONS: We report polymicrobial keratitis involving Pseudomonas aeruginosa, Acinetobacter baumannii, and Ochrobactrum anthropi for the first time in the Republic of Korea.
Acinetobacter baumannii ; Acinetobacter ; Anterior Chamber ; Ceftazidime ; Corneal Ulcer ; Cyclopentolate ; Doxycycline ; Eyelids ; Female ; Gentamicins ; Humans ; Hyperemia ; Inflammation ; Keratitis ; Middle Aged ; Ochrobactrum anthropi ; Ochrobactrum ; Pseudomonas aeruginosa ; Pseudomonas ; Republic of Korea ; Slit Lamp ; Ultrasonography ; Visual Acuity ; Voriconazole

PURPOSE: We analyzed time series changes in cataract surgeries in Korea, and provide basic data to enhance the efficiency of medical services for cataract surgery. METHODS: Among cataract surgery statistics registered in the Korean National Health Insurance Cooperation from 2006 to 2012, we used data regarding the number of patients and operations and the number of patients and operations per 100,000 people. We analyzed various time series changes, including differences by sex and age. RESULTS: The total numbers of patients from 2006 to 2012 by year were 207,370; 228,170; 250,289; 268,548; 289,867; 308,111; and 302,182, respectively. The total numbers of operations from 2006 to 2012 by year were 272,920; 305,807; 338,332; 365,874; 398,338; 428,158; and 420,905, respectively. The number of patients and operations per 100,000 people were highest in men 80 to 84 years old and women 75 to 79 years old. Comparing the number of operations in 2006 and after, the patient age group with the highest increase rate changed from over 85 years old to 75–79 years old since 2010 in men and from over 85 years old to 50–54 years old since 2009 in women. For each year investigated, the number of operations performed was higher than the number of patients who received operations. CONCLUSIONS: Over the study period, the number of cataract surgeries increased, while the age of cataract patients decreased. Additionally, the number of cataract-related surgeries increased in relation to the number of patients.
Cataract Extraction ; Cataract* ; Epidemiology ; Female ; Humans ; Korea* ; Male ; National Health Programs