• Journal of Korean Foot and Ankle Society
• /
• v.21 no.3
• /
• pp.93-97
• /
• 2017

Purpose: The aim of this study was to evaluate the radiological and clinical outcomes of scarf osteotomy for hallux valgus (HV) deformity in elderly patient with osteoporosis. Materials and Methods: A total of 58 elderly patients (mean age, 72.6 years) underwent scarf osteotomy for HV deformity between 2008 and 2015. The mean follow-up period was 24.4 months. Of the 58 patients, 42 were diagnosed with osteoporosis and 16 were diagnosed as normal. The radiological and clinical outcomes were assessed preoperatively, postoperatively, and at final follow-up, including HV angle, intermetatarsal (IM) angle, American Orthopaedic Foot and Ankle Society (AOFAS) score, patient satisfaction, visual analogue scale (VAS), and complication. Results: There was no significant difference in HV angle and IM angle between the osteoporosis group and normal bone mineral densitometry group at all time points, preoperative, postoperative, and final follow-up. Moreover, there was no statistically significant difference between the two groups with respect to the AOFAS score and VAS evaluations. In the osteoporosis group, the mean HV angle improved from $36.7^{\circ}$ preoperatively to $11.3^{\circ}$ at the time of final follow-up, and the mean IM angle improved from $13.2^{\circ}$ to $5.7^{\circ}$. The mean AOFAS score improved from 52.6 preoperatively to 89.1 at the time of final follow-up. With respect to satisfaction, 83.4% of patients were very satisfied or satisfied. There were no serious complications, and all cases showed complete union at the osteotomy site. Conclusion: We believed that scarf osteotomy is a safe, effective procedure for the correction of elderly patients with osteoporosis.

• Korean Journal of Applied Biomechanics
• /
• v.17 no.3
• /
• pp.11-21
• /
• 2007

The purpose of this study was to examine the differences of kinematics and muscle activities depending on the changes of angle approaching balls during backhand drive in squash. The results are as follows. Stride time took the longest at AD2 and step lengths were the biggest at AD1 of left foot contact and right foot contact and AD2 of impact and follow-through. The center of gravity and the speed of racket head were the highest at AD3 and at AD2. Angle of shoulder joint were the biggest at AD1 of left foot contact, right foot contact and impact and AD3 of follow-through. Angle of elbow joint were the biggest at AD3 of left foot contact, right foot contact and follow-through and AD2 of impact. Angle of pelvis joint were the biggest at AD2 of left foot contact, AD1 of right foot contact and AD3 of impact and follow-through. Angle of knee joint were the biggest at AD2 of left foot contact, AD1 of right foot contact and AD3 of impact and follow-through. Angle of ankle joint were the biggest at AD1 of left foot contact and AD3 of right foot contact, impact and follow-through. According to the analysis results of triceps brachii, latissimus dorsi, brachioradialis muscle and flexor carpi ulnaris muscle activities were high at AD1 of all phases. Analysis results of vastus lateralis, vastus medialis, tibialis anterior and gastrocnemius medial muscle activities were high at AD2 of phase1 and phase3. Those of vastus lateralis, vastus medialis and tibialis anterior, gastrocnemius medial were high at AD3 of Phase 2 and AD1 of phase2.

• The Journal of Korean Physical Therapy
• /
• v.23 no.1
• /
• pp.13-19
• /
• 2011

Purpose:This study was designed to investigate difference in isokinetic muscle strength in the knee extensor muscle and characteristic differences in muscle strength between males and females through the ankle joint angles. Methods: Seventy-four subjects participated in this study. There were two groups: 36 males and 38 females. The mean age of the men was 24.58 years and women was 23.74 years. Subjects were seated on a CON-TREX LP (leg press) lean to back of chair, and there bodies were fixed by straps with the hip joint at an angle of $130^{\circ}$. After randomly fixing the ankle joint at $0^{\circ}$, $20^{\circ}$, and $40^{\circ}$ of plantar flexion (PF) in range of full extension of knee joint. We studied force max average, force max average/kg, power average, and total work through the angle of the ankle joint when the knee joint was extended from $90^{\circ}$ to $180^{\circ}$. Results: In the male group, all maximum measured value showed at the ankle joint $0^{\circ}$, all minimum measured value showed at $40^{\circ}$ PF (p<0.01). In the female group, all maximum measured value showed at the ankle joint $20^{\circ}$ PF, especially the power average increased significantly. All minimum measured value showed $40^{\circ}$ PF (p<0.01). Conclusion: There are differences between males and females in isokinetic muscle strength of the knee extensor through ankle joint angles in healthy adults. Males and Females have different characteristics of muscle strength through the ankle joint angles.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.891-896
• /
• 2008

Behavior of the existing tunnel in the jointed rocks was affected by the adjacent slope excavation. In this study, large scale model tests were conducted. To investigate the tunnel distortion depending on the excavated slope angle and the joint dip of the ground performed model tests were numerically back analyzed. Consequently, as the joint dip and slope angle became larger, the tunnel distortion was tended to be larger. Ground displacement was also greatly dependent on the joint dip and the excavated slope angle, which indicated the possibility of the optimal slope reinforcement.

• Korean Journal of Applied Biomechanics
• /
• v.14 no.2
• /
• pp.153-166
• /
• 2004

The purpose of this study was to investigate time of the phase, angle of the right ankle, knee, and hip joint, lateral angle of the trunk, mediolateral displacement of COM, and vertical displacement of COM between two groups while executing grand battement $jet{\acute{e}}$ $\acute{a}$ la seconde in a center exercise setting through 3D video analysis. The subjects participated in this study were skilled and unskilled 6 female ballet majors in Busan, respectively. The conclusions are as follows: 1. The time of the phase 2 was faster than P3. It shows a significant difference(p<.05) for P1 and P4 between skilled and unskilled groups 2. The angle of He right ankle joint has a significant difference(p<.05) at E4 between skilled and unskilled groups. The angle of the right knee joint has no significant difference at all events between skilled and unskilled groups. The angle of the right hip joint has a significant difference(p<.001) at E3 between skilled and unskilled groups. 3. The lateral angle of the trunk has a significant difference(p<.05) at E1 and at E5 between skilled and unskilled groups. The skilled group of the lateral angle of the trunk was lower than the unskilled group. However the skilled group's lateral angle of the trunk was bigger than the unskilled group at E3. It has significant difference(p<.001) at E3 between skilled and unskilled groups. 4. The mediolateral displacement of COM has no significant difference at all events between skilled and unskilled groups. The vertical displacement of COM has a significant difference(p<.01) at E3 between skilled and unskilled groups.

• Korean Journal of Applied Biomechanics
• /
• v.15 no.4
• /
• pp.13-24
• /
• 2005

The purpose of this study was to compare kinematic data between experts and novices, and identify difference kinematic parameters changing direction to kick in penalty kick of soccer play. Novice subjects were 5 high school students Who has never been experienced a soccer player, and expert subjects were 5 competitive high school soccer players. The 3-d angle was calculated by Euler's Angle by inertial axis and local axis with three-dimensional cinematography. Kinematic parameters in this study consisted of angles of knee joints, hip joints, lower trunk and upper trunk when the support foot was contacted on ground and kicking foot impacted the ball. The difference of angle of knee joints in the flexion/extension was insignificantly showed below $4{\sim}9^{\circ}$ in groups and directions of ball at the time of support and impact. But the difference of angle of hip joint was significant in groups and directions of ball at the time of support and impact. Specially the right hip joint of experts were more flexed about $12^{\circ}$($43.99{\pm}6.17^{\circ}$ at left side, $31.87{\pm}4.49^{\circ}$ at right side), less abducted about $10^{\circ}$ ($-31.27{\pm}4.49^{\circ}$ at left side, $-41.97{\pm}6.67^{\circ}$ at right side) at impact when they kicked a ball to the left side of goalpost. The difference of amplitude angle in the trunk was significantly shown at upper trunk not lower trunk. The upper trunk was external rotated about $30^{\circ}$ (novice' angle was $-16.3{\pm}17.08^{\circ}$, expert's angle was $-43.73{\pm}12.79^{\circ}$) at impact. Therefore the significant difference of kinematic characteristics could be found at the right hip joint and the upper trunk at penalty kick depending on the direction of kicking.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2002.03a
• /
• pp.501-508
• /
• 2002

The percentage of a mountainous district in our country is comparatively high but the concern for rock mass has been disregarded for a long time. Especially for rock slope, the most important factors are geometric characteristics and their shear strength parameter. In this paper, parametric studies are performed using the distinct element computer program UDEC-BB for rock slopes. Parameters adopted in this paper are joint angle, spacing, persistence, aperture and shear strength parameters (JRC, JCS, basic friction angle). To estimate slope stability, shear strength reduction method is used. The most important factors affecting rock slope stability are joint angle and spacing. The relationship between average displacement calculated by UDEC-BB and safe factor by shear strength reduction method is researched.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.64 no.5
• /
• pp.792-798
• /
• 2015

Joint angle generally can be measured to check the recovery process in rehabilitation field. This paper suggests to measure joint angle with Infrared sensor based on triangulation principle. We performed various experiments to find the optimal condition of the sensor’s attached distance, height, and angle. The results were compared with commercial goniometer for accuracy. The proposed infrared joint angle sensor can be effectively used in rehabilitation and sport science fields.

• Journal of Korean Foot and Ankle Society
• /
• v.16 no.2
• /
• pp.101-107
• /
• 2012

Purpose: The aim of this study was to investigate the radiological characteristics of the osteoarthritis of the second metatarsophalangeal (MTP) and tarsometatarsal (TMT) joint. Materials and Methods: Between January 2002 and August 2010, 27 patients (33 feet) who had second metatarsal osteoarthritis (OA) were reviewed retrospectively. Group 1 was 14 patients (17 feet) with second MTP joint OA. Group 2 was 13 patients (16 feet) with second TMT joint OA. Group 3 was 24 patients (25 feet) had hallux valgus without second metatarsal (MT) OA as control. Weight bearing foot anteroposterior (AP) and lateral view were checked, and measured hallux valgus angle, metatarsus adductus angle (MAA), second MT functional length, first and second MT length by Hardy & Clapham method on AP view, angle of second MT with horizontal plane, calcaneal pitch, talo-first MT on lateral view. Results: On weight bearing foot AP view, second MT functional length of group 1, 2, 3 was 2.4 mm, -0.1 mm, 0.7 mm and MAA of group 1, 2, 3 was $17.7^{\circ}$, $17.7^{\circ}$, $14.5^{\circ}$. Second MT functional length of group 1 was longer than control group and it was statistically significant. MAA was significant different between group 1-3 and group 2-3. Angle of second MT with horizontal plane of group 2 was smaller than control group and it was statistically significant. Other radiographic parameters have no statistical significance. Conclusion: Group 1 has long functional length of second MT and group 2 has small angle of second MT with horizontal plane.

• Proceedings of the KIEE Conference
• /
• 2006.07d
• /
• pp.1929-1930
• /
• 2006

Human like robot arm posture for grasping by considering the shape of the target object is quite a challenge in the field of robotics. In this paper, an optimized grasp posture with respect to the shape of the object considering the wrist joint angle and elbow elevation angle, in order to verify that the grasp posture is human like has been proposed. Given a target object, the candidates for grasp are computed by the method described in this paper. For each candidate, the closed loop inverse kinematics has been solved for the corresponding hand position and orientation. From the obtained joint angles through inverse kinematics, the elbow elevation angle has been computed and compared with the elbow elevation angle obtained through human movement data by the characteristic equation. After considering all the candidates, the hand position and orientation with minimum wrist joint and difference in elbow elevation angles has been utilized as the optimized grasp posture. Simulation results are presented.