• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.10
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• pp.1205-1210
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• 2011

Spinal instability known to be related to low back pain. However, the quantitative definition of spinal instability has not been established because there is a lack of consensus regarding clinical and radiological studies. In addition, the major factors affecting such instability have not been elucidated, although disc degeneration, disc injury, ligament injury, and isthmic defects are considered to result in such problems. In this study, individual and combined influences on spinal instability with a three-dimensional finite element model of a one-level lumbar spinal motion segment were investigated, under the assumption that the rotation and translation in the sagittal plane under flexion and extension represented the instability indices. The results could be helpful in understanding the causes and mechanisms of spinal instability in the lumbar spine.

• Physical Therapy Rehabilitation Science
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• v.7 no.1
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• pp.35-40
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• 2018

Objective: The purpose of this study was to investigate the immediate effect of applying self-myofascial release (SMR) to the plantar fascia using a foam roller on hamstring and lumbar spine superficial back line (SBL). Design: Randomized controlled trial. Methods: Thirty-one healthy adults agreed to the method and purpose of the study. Selection and exclusion criteria were screened, and baseline measurements for the Toe Touch test and passive straight leg raise (PSLR) test were obtained. The participants were then randomly assigned to the SMR group or the sham group. After group assignment, the SMR group rolled the surface of the foot from the heel to the metatarsal head using a foam roller for 5 minutes. The sham group received passive mobilization of the ankle joint in the supine position. Afterwards, the Toe Touch test and the passive straight leg-raise test were re-assessed. Results: In the SMR group, the Toe Touch test results showed significant improvement (p<0.05). Left and right PSLR test results showed a significant increase (p<0.05). In the sham group, there was no significant difference between pre and post-test results. The SMR group showed a significant difference in the PSLR test and Toe Touch test compared to the sham group (p<0.05). Conclusions: The results of this study showed that SMR on the plantar fascia was immediately effective for improving the flexibility of the SBL of the lumbar spine and hamstring.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.2
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• pp.17-27
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• 2015

PURPOSE: The purpose of this study was to compare the effects of three interventions (intervention by passive range of motion exercise plus manual cervical traction, Mulligan's joint mobilization, and strengthening exercises) after Kaltenborn's joint mobilization on the cervical spine alignment, and muscle activity in patients with a forward head posture. METHODS: The subjects were 39 students from H University in Chungnam and C University in Jeonbuk. The subjects in each group attended training sessions three times a week for four weeks. We used one-way ANOVA and Scheffe's post hoc test to compare values between groups, and used paired t-test to compare the values of the dependent variables within groups. RESULTS: The results showed that the active intervention group experienced a significant increase compared to the passive intervention group in terms of the craniovertebral angle, cervical lordosis angle, and had significant decreases compared to the passive intervention group in terms of the upper trapezius muscle activity. The active intervention group also had significant increases in craniovertebral angle and decreased anterior scalene muscle activity than the active-assistive intervention group. The active-assistive intervention group had significant decreases compared to the active intervention group in terms of the serratus anterior, levator scapulae, and splenius capitis muscle activity. CONCLUSION: It appears that the subjects with a forward head posture had significant improvements in the cervical lordosis angle, cranial rotation angle, craniovertebral angle, and muscle activity after intervention by Mulligan's joint mobilization (active-assistive intervention component) and strengthening exercises (active intervention component) after applying Kaltenborn's joint mobilization.

• Journal of Korean Neurosurgical Society
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• v.37 no.5
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• pp.364-369
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• 2005

Objective: Spinal instrumentation without fusion often fails due to biological failure of intervertebral joints (spontaneous fusion, degeneration, etc). The purpose of this study is to investigate the influence of fixation rigidity on viability of intervertebral joints. Methods: Twenty pigs in growing period were subjected to posterior segmental fixation. Twelve were fixed with a rigid fixation system(RF) while eight were fixed with a flexible unconstrained implant(FF). At the time of the surgery, a scoliosis was created to monitor fixation adequacy. The pigs were subjected to periodic radiological examinations and 12pigs (six in RF, six in FF) were euthanized at 12-18months postoperatively for analysis. Results: The initial scoliotic curve was reduced from $31{\pm}5^{\circ}$ to $27{\pm}8^{\circ}$ in RF group (p=0.37) and from $19{\pm}4^{\circ}$ to $17{\pm}5^{\circ}$ in FF group (p=0.21). Although severe disc degeneration and spontaneous fusion of facet joints were observed in RF group, disc heights of FF group were well maintained without major signs of degeneration. Conclusion: The viability of the intervertebral joints depends on motion spinal fixation. Systems allowing intervertebral micromotion may preserve the viability of intervertebral discs and the facet joint articular cartilages while maintaining a reasonably stable fixation.

• Journal of Korean Neurosurgical Society
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• v.53 no.6
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• pp.331-336
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• 2013

Objective : The offset connector can allow medial and lateral variability and facilitate intralaminar screw incorporation into the construct. The aim of this study was to compare the biomechanical characteristics of C7 intralaminar screw constructs with and without offset connector using a three dimensional finite element model of a C6-7 cervical spine segment. Methods : Finite element models representing C7 intralaminar screw constructs with and without the offset connector were developed. Range of motion (ROM) and maximum von Mises stresses in the vertebra for the two techniques were compared under pure moments in flexion, extension, lateral bending and axial rotation. Results : ROM for intralaminar screw construct with offset connector was less than the construct without the offset connector in the three principal directions. The maximum von Misses stress was observed in the C7 vertebra around the pedicle in both constructs. Maximum von Mises stress in the construct without offset connector was found to be 12-30% higher than the corresponding stresses in the construct with offset connector in the three principal directions. Conclusion : This study demonstrated that the intralaminar screw fixation with offset connector is better than the construct without offset connector in terms of biomechanical stability. Construct with the offset connector reduces the ROM of C6-7 segment more significantly compared to the construct without the offset connector and causes lower stresses around the C7 pedicle-vertebral body complex.

• PNF and Movement
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• v.17 no.1
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• pp.41-46
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• 2019

Purpose: Continuous use of a smartphone increases the angle of forward bending of the user's cervical vertebrae, causing pain in the shoulders and back, including the thorax, lumbar region, and vertebrae. Although there are many studies on changes in the cervical spine due to smartphone usage, the changes in the shoulders, thoracolumbar spine, and pelvic have rarely been compared. The purpose of this study is to investigate the change in the spinal segments, shoulders, and pelvic when using a smartphone with both hands while in the standing position. Methods: This study was conducted on 35 adults in their twenties. The selection criteria for the subjects were limited to those in a similar age group, thus excluding posture differences according to age, and to those who did not have specific diseases or pain in the spinal and musculoskeletal system for 12 months prior to the study. In this study, we used a 3D spinal diagnostic imaging system (Back Mapper, Frickenhausen) to compare the changing conditions in each vertebral segment before and during smartphone usage with both hands while in the standing position. Posture differences according to smartphone usage were compared using the paired t-test for the motion of each spinal segment. Results: This study showed that the thoracic and lumbar angle increased posteriorly during smartphone usage (p<0.05). In addition, the anterior rotation angle of the shoulder bone significantly increased, but no significant difference occurred in the pelvic region. Conclusion: Based on the results of this study, smartphone usage with both hands while in the standing position showed that the spine, as a whole, forms a kyphotic curve. Therefore, we propose to present a postural guideline for correct smartphone usage, considering the change in each vertebral segment.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.3
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• pp.131-137
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• 2014

Objectives The purpose of this study was to compare the effects of MSAT (Mostion style acuputure treatment) on piriformis muscle regarding leg radiating pain with HIVD of L-SPINE. Methods Forty patients who received inpatient treatment from Febuarary 1 to March 31, 2014 in the Daejon-Jaseng oriental medicine hospital were divided into 2 groups by blocked randomization : Group A (n=20)=routine treatment on HIVD of L-SPINE with MSAT on piriformis muscle and Group B (n=20)=routine treatment on HIVD of L-SPINE (acupuncture, Shinbaro pharmacopuncture, herb medication, chuna treatment and physiotherapy). The MSAT (Mostion style acuputure treatment) on piriformis muscle was administered each day and both groups were received routine treatment each day. Evaluations were made before treatment, after 3 days and 7 days, and before discharge using the NRS (numeric rating scale) and ODI (oswestry disability index). The statistically significance was evaluated by SPSS 18.0 for windows. Results Compared to before treatment, the NRS (numeric rating scale) and ODI (oswestry disability index) of both A and B groups after 3, 7 days and before discharge of treatment significantly decreased (p<0.05). Regarding group comparison, the NRS (numeric rating scale) and ODI (oswestry disability index) of A group was significantly lower than the B group at 3, 7 days, before dischanre (p<0.05). Regarding improvement of the NRS (numeric rating scale) and ODI (oswestry disability index), A group was significantly lower than the B group at 3 day (NRS), 7day (ODI) (p=0.000) but there was no significant difference between the two groups at 7 days (NRS) and before discharge (p>0.05). Conclusions Compared to just routine treatment, the MSAT (Mostion style acuputure treatment) on piriformis muscle significantly improved the NRS (numeric rating scale) and ODI (oswestry disability index) after 3, 7 days, and before discharge. Because early intervention determines the grade of Leg radiating pain with HIVD of L-SPINE, the MSAT (Mostion style acuputure treatment) on piriformisat the early stage will be clinically helpful to patients.

• Journal of Biomedical Engineering Research
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• v.26 no.3
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• pp.151-155
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• 2005

Interspinous spacers have been developed as an alternative surgical treatment for laminectomy or fusion with pedicle screws and rods for the treatment of lumbar spinal stenosis. However, its biomedical efficacies are well not known. In this study, we evaluated kinematic behaviors of the surgical and the adjacent levels before and after inserting interspinous spacers. Three porcine lumbar spines were prepared. On each specimen, an interspinous spacer was inserted at the L4-L5. Flexion-extension moments (0, 2.5, 5.0, 7.5, 10Nm) were applied. A stereophotogrammetric set-up with DLT algorithm was used to assess the three-dimensional motions of the specimen where three markers $({\square}0.8mm)$ were attached to each vertebra. Results showed that extension motion decreased by $15-24\%$ at the surgical level (L4-L5) after insertion of interspinous spacer. At the adjacent levels, the range of motion remained unchanged. In flexion, no significant changes in motion were observed regardless of levels. Therefore, our experimental results demonstrated the interspinous spacer is very effective in limiting the extension motion that may cause narrowing of the spinal canal and vertebral foramen while maintaining kinematic behaviors at the adjacent levels. Further, these results suggested that the use of interspinous spacer may be able to prevent lower back pain at the surgical level and to lower the incidence of degenerative changes at the adjacent levels.

• PNF and Movement
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• v.20 no.3
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• pp.341-349
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• 2022

Purpose: The purpose of this study is to compare the muscle activity of the hip abductors and the ratio between the hip abductor muscle group according to the range of hip abduction during the clam exercise. Methods: This study was conducted on 18 healthy men in their aged 20 to 29 who had not been diagnosed with spine-related diseases. The subjects performed a clam exercise without rotation of the pelvis in a state of 60° hip flexion and 90° knee joint flexion in the side-lying position. Using Myomotion equipment and EMG, the muscle activity of the hip abductor muscles and the activity ratio between the hip abductor muscle group were measured during the clam exercise by dividing the range into initial, mid-range, and terminal sections. Repeated measures analysis of variants was employed to compare the activity and use of hip abductor muscles according to range of motion during the clam exercise. Results: Gluteus medius muscle activation was significantly increased in the comparison of muscle activity in the initial, mid-range, and terminal sections of hip abduction. Tensor fasciae latae muscle activation was significantly increased in the comparison of muscle activity in all range of motion sections as well. The gluteus medius-tensor fasciae latae muscle activation ratio was significantly increased in the terminal section compared to the initial section. Conclusion: The gluteus medius and tensor fasciae latae had higher muscle activities as they approached the terminal section during the clam exercise, and the hip abduction activity ratio of the gluteus medius and tensor fasciae latae was higher as the range of motion approached the terminal section.

• Journal of Korean Neurosurgical Society
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• v.46 no.6
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• pp.532-537
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• 2009

Objective : Recently, motion preservation has come to the forefront of emerging technologies in spine surgery. This is the important background information of the emergence of cervical arthroplasty as an alternative to arthrodesis that offers the promise of restoring normal spinal movement and reduces a kinematic strain on adjacent segments. The study was designed to evaluate early surgical outcome and radiological effects of $Bryan^{(R)}$ cervical disc prosthesis. Methods : The authors retrospectively reviewed radiographic and clinical outcomes in 52 patients who received the $Bryan^{(R)}$ Cervical Disc prosthesis, for whom follow-up data were available. Static and dynamic radiographs were measured by computer to determine the angles formed by the endplates of the natural disc preoperatively, those formed by the shells of the implanted prosthesis, the angle of functional spine unit (FSU), and the C2-7 Cobb angle. The range of motion (ROM) was also determined radiographically, whereas clinical outcomes were assessed using Odom's criteria, visual analogue pain scale (VAS) and neck disability index (NDI). Results : A total of 71 $Bryan^{(R)}$ disc were placed in 52 patients. A single-level procedure was performed in 36 patients, a two-level procedure in 13 patients, and a three-level procedure in 3. Radiographic and clinical assessments were made preoperatively. Mean follow-up duration was 29.2 months, ranging from 6 to 36 months. All of the patients were satisfied with the surgical results by Odom's criteria, and showed significant improvement by VAS and NDI score (p < 0.05). The postoperative ROM of the implanted level was preserved without significant difference from preoperative ROM of the operated level (p < 0.05). 97% of patients with a preoperative lordotic sagittal orientation of the FSU were able to maintain lordosis. The overall sagittal alignment of the cervical spine was preserved in 88.5% of cases at the final follow up. Interestingly, preoperatively kyphotic FSU resulted in lordotic FSU in 70% of patients during the late follow up, and preoperatively kyphotic overall cervical alignment resulted in lordosis in 66.6% of the patients postoperatively. Conclusion : Arthroplasty using the $Bryan^{(R)}$ disc seemed to be safe and provided encouraging clinical and radiologic outcome in our study. Although the early results are promising, this is a relatively new approach, therefore long-term follow up studies are required to prove its efficacy and its ability to prevent adjacent segment disease.