압축센스(Compressed SENSE) 기법은 검사 시간을 획기적으로 단축할 수 있으나, 시간 단축을 위한 기법적용 시 가속계수를 증가시키면 인공물의 발생이 영상에서 증가하는 문제점이 있다. 이에 인공물이 발생하지 않으면서 검사 시간을 최대한 단축할 수 있는 최적의 압축센스 가속계수를 제시하고자 하였다. 연구 방법은 인공물이 발생하지 않는 가속계수 1.0을 기준으로 0.5 간격씩 5.0까지 무릎관절 자기공명영상의 팬텀 실험과 임상실험 영상을 획득한 후, 방사선사 10명이 5점 척도로 영상을 평가하여 유의한 차이가 있는지 판단하였다. 연구 결과 T1 강조영상과 T2 강조 영상 모두 팬텀 실험은 가속계수 2.0 이하로 하였을 때 임상실험은 3.0 이하로 하였을 때 기준이 되는 1.0 영상과 차이가 없었다. 결론적으로 무릎관절 자기공명영상 검사 시 인공물이 발생하지 않으며 검사 시간을 최대로 단축할 수 있는 최적의 압축센스 가속계수는 팬텀 실험의 경우 2.0, 임상실험의 경우 3.0이 적정하리라 판단된다.

This study analyzed 214 sports knee braces found on Chinese websites between October 2022 and November 2022 to assess product type (impact protection material, fastening method, and protection method), material composition, size, weight, and main characteristics. The product type was further categorized according to (1) use of hard guard and soft guard protection method; (2) cover type, strap type, and slip-on type fastening method; and (3) pressure type and support type protection method. It also noted the physical shock protection materials used, including foam (EVA or polyurethane) attached to joints as a buffer material and plastic (TPU or PP) that protects the user’s knee from external impacts. The study found that the materials that primarily comprise sports knee braces are a combination of nylon, polyester, and neoprene. Additionally, it found that most sports knee braces available on the market are available in three sizes based on knee circumference: M (35–38cm), L (38–41cm), and XL (41–44cm), while some products are available in one size only. Furthermore, the majority of the 214 products studied weighed 200g, followed by 1,000g. Finally, in terms of product characteristics, many sports knee braces utilize ring-shaped silicone pads to distribute the load pressure on the knees or incorporate sturdy adhesive velcro to improve knee stability.

Background: Floor sit-to-stand (FSTS) places a higher load on the knees than chair sit-to-stand (CSTS). It is difficult to experimentally measure the maximum knee joint force during sit-to-stand motion. Objectives: This study's objectives were twofold: firstly, to quantify the differences in knee joint force between FSTS and CSTS, and secondly, to identify the angles at which the maximum knee joint force occurs during these motions. Design: Computer simulation study. Method: This study was conducted on 4 adult male subjects in their 20s. The FSTS and CSTS motion trajectories of the subjects were acquired using 3- dimensional motion analysis equipment. Using these, the human body mass model of the program was modified according to the subject, and the knee joint force was calculated. Also, the knee angle at which the maximum knee joint force occurs was found. Results: When the subjects performed the FSTS motion, a knee joint force that was up to about 160% higher than that of the CSTS motion occurred, and the angle at which the maximum knee joint force occurred was different between the sitting sequence(FSTS motion: 56~58 degree, CSTS motion: 78~82 degree) and the standing sequence(FSTS motion: 98~100 degree, CSTS motion: 70~74 degree). Conclusion: By comparing FSTS motion with CSTS motion, it is expected that it can be used as a quantitative guide for the effect of motion similar to FSTS motion on the knee when prescribing exercise for the elderly or patients with knee-related lesions.

본 연구의 목적은 허벅다리걸기 시 유도 선수들의 무릎 관절 부상 경험이 운동학적 요인과 압력 중심 요인들에 미치는 영향을 분석하는데 있었다. 본 연구에는 허벅다리걸기를 특기로 하는 오른손잡이 남 자 대학 유도 선수 중 최근 2년 이내 무릎 관절 부상 경험이 있었던 13명(연령, 20.69.1±0.75 세; 신장, 172.85±4.81 cm; 체중, 74.92±5.51 kg; 경력, 8.92±0.95 세)과 상해 경험이 없었던 13명(연령, 21.08.1±0.76 세; 신장, 172.54±6.32 cm; 체중, 76.62±9.09 kg; 경력, 9.46±0.94 세)이 두 그룹으로 나 뉘어 피험자로 참여하였다. 두 그룹의 발목, 무릎, 힙 관절각도 변인과 압력 중심 가동범위와 속도 요인들 의 차이를 분석하였다. 그 결과, 부상 경험 그룹은 부상 경험이 없었던 그룹에 비해 허벅다리걸기 기술 발 휘 시 한발 지지 구간 중 E3에서의 무릎 관절 굴곡 각도와 E4에서의 힙 관절 신전 각도에서 작은 수치를 나타내었다. 더불어 부상 경험 그룹은 부상 경험이 없었던 그룹에 비해 한발 지지 구간에서 압력 중심 가동 범위와 전방 이동 속도 요인에서도 낮은 수치를 나타내었다.

Background: Kinesio taping (KT) is an intervention method used to improve early function after surgery; however, the effect of KT varies depending on the intervention method. Objectives: To investigated systematically review and quantitatively analyze the effect of KT randomized controlled trials (RCTs) applied to Total knee arthroplasty (TKA) to determine the value of the treatment method for TKA patients. Design: A systemic review and meta-analysis. Methods: Studies were identified by searching multiple electronic databases from January 2023 to February 2023. We selected RCTs comparing KT or no treatment, standard physical therapy, multimodal therapeutic approaches. When possible, we pooled data using random-effects meta-analysis. The Cochrane Bias Method Group's seven-item risk of bias (RoB) assessment tool was used for RCTs. The main outcomes were pain, swelling, and ROM. Results: Three trials (290 patients) provided sufficient data and were similar enough to be pooled for meta-analysis. The standardized mean difference for a reduction of pain was SMD = -1.02, 95 % CI -1.93 to -0.12; p= 0.03; I2= 92 %. The standardized mean difference for a reduction of swelling was SMD= - 0.23, 95 % CI -0.50 to -0.05; p= 0.10; I2= 58 %. The standardized mean difference for ROM was SMD= 1.06, 95 % CI -0.08 to 2.20; p= 0.07; I2= 95 %. Conclusion: KT has a large effect on pain reduction in TKA patients and could be used as an additional treatment option, but a small effect was observed in swelling and ROM.

자기공명영상은 영상 의학 분야에서 다른 진단 장비에 비해 연부 조직에 대한 높은 대조도를 지니고 있고 인대의 손상, 주변 조직의 염증, 골염 등의 병변을 진단하는 데 유용하여 연골 및 관절 병변의 진단에 널리 이용되고 있다. 또한, 기존 고식적 TSE 기법 외에도 SMS 기법, DL 기법, CS 기법, 병렬 영상 기법 등 다양한 펄스 시퀀스들이 개발되고 임상에서 사용되고 있다. 본 연구는 무릎 관절 자기공명영상 검사에서 얇은 절편 검사 시 고식적 TSE 기법, SMS TSE 기법, DL TSE 기법에서 영상을 획득하여 각 각의 영상의 비교를 통해 무릎 관절 영상 획득에 최적의 기법에 대하여 알아보고자 한다. 무릎 관절 질환의 진단을 위해 본원에 내원한 환자를 대상으로 고식적 TSE 기법, SMS TSE 기법, DL TSE 기법을 적용하여 시상면 T2 강조 영상을 획득한 후 신호 대 잡음비, 대조도 대 잡음비, 검사 시간, 영상의 질 평가를 정량적, 정성 적 방법으로 비교 분석하였다. 연구 결과 세 가지 기법으로 획득한 영상 비교 시 통계적으로 유의한 차이가 있었으며, 환자 의 상태와 임상의 상황을 종합적으로 고려하여 적절한 기법을 선택한다면, 최적의 영상을 제공할 수 있다고 생각된다.

Background: Individuals with scapular winging have a weak serratus anterior (SA) muscle, and to compensate, the pectoralis major (PM) and upper trapezius (UT) muscles excessively activate, which can cause upper extremity dysfunction. This study aimed to compare the effects of isometric horizontal abduction (IHA) on SA, PM, and UT muscle activity, as well as the SA/PM and SA/UT muscle activity ratios during knee push-up plus (KPP) at 90° and 120° of shoulder flexion. Objects: This study aimed to compare the effects of IHA on SA, PM, and UT muscle activity, as well as the SA/PM and SA/UT muscle activity ratios during KPP at 90° and 120° of shoulder flexion. Methods: This study, conducted at a university research laboratory, included 20 individuals with scapular winging. Participants performed KPP with and without IHA at 90° (KPP90) and 120° (KPP120) of shoulder flexion. SA, PM, and UT muscle activity were measured using surface electromyography. Results: PM activity in KPP90 with IHA was significantly lower than KPP90 and in KPP120 was significantly lower than KPP90. UT activity was significantly greater with IHA than without IHA and at 120° than 90° of shoulder flexion. SA/PM muscle activity ratio was significantly higher in KPP90 with IHA than without IHA and in KPP120 than in KPP90. SA/UT muscle activity ratio was significantly lower with IHA than without IHA. Conclusion: KPP90 with IHA and KPP120 are effective exercises to reduce PM activity and increase SA/PM muscle activity ratio. However, applying IHA in KPP90 also reduces SA/UT muscle activity ratio, implying that it would be preferable to apply KPP120 in individuals overusing their UT muscles.

Background: Osteoarthritis is a common condition with an increasing prevalence and is a common cause of disability. Osteoarthritic pain decreases the quality of life, and simple gait training is used to alleviate it. Knee osteoarthritis limits joint motion in the sagittal and lateral directions. Although many recent studies have activated orthotic research to increase knee joint stabilization, no study has used patellar tendon straps to treat knee osteoarthritis. Objects: This study aimed to determine the effects of patellar tendon straps on kinematic, mechanical, and electromyographic activation in patients with knee osteoarthritis. Methods: Patients with knee osteoarthritis were selected. After creating the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), leg length difference, Q-angle, and thumb side flexion angle of the foot were measured. Kinematic, kinetic, and muscle activation data during walking before and after wearing the orthosis were viewed. Results: After wearing the patellar tendon straps, hip adduction from the terminal stance phase, knee flexion from the terminal swing phase, and ankle plantar flexion angle increased during the pre-swing and initial swing phases. The cadence of spatiotemporal parameters and velocity increased, and step time, stride time, and foot force duration decreased. Conclusion: Based on the results of this study, the increase in plantar flexion after strap wearing is inferred by an increase due to neurological mechanisms, and adduction at the hip joint is inferred by an increase in adduction due to increased velocity. The increase in cadence and velocity and the decrease in gait speed and foot pressure duration may be due to joint stabilization. It can be inferred that joint stabilization is increased by wearing knee straps. Thus, wearing a patellar tendon strap during gait in patients with knee osteoarthritis influences kinematic changes in the sagittal plane of the joint.

Background: Studies using Smovey and Vibration foam rollers are mostly conducted with normal adults, breast cancer patients, and athletes. However, there are not many studies applied to stroke patients to date. Objectives: The purpose of this study is to investigate the effect of vibration exercise on the range of motion of the shoulder and knee joints in stroke patients. Design: A randomized controlled trial. Methods: A total of 36 stroke patients, with 12 in the Smovey and Vibration foam roller group (SVG), 12 in the Smovey and Non-Vibration foam roller group (SNVG), and 12 in the control group (CG) were randomly assigned to exercise three times a week for 6 weeks. The range of motion of the shoulder and knee joints was measured for each group before and after 6 weeks of exercise. For joint range of motion, shoulder flexion and extension and knee flexion and extension were measured using BPMpro. Results: In terms of the difference in time, the flexion and extension of the shoulder and the flexion and extension of the knee on the paretic side were significant in the SVG and SNVG. The CG was not significant. Shoulder flexion and extension and knee flexion and extension on the unaffected side were all insignificant. The differences between each group were significant between the SVG and the CG and the SNVG and the CG. SVG and SNVG were not significant. Conclusion: It was found that vibration exercise had a positive effect on the range of motion of the shoulder and knee joints. Therefore, it is thought that vibration exercise can be provided as a clinical intervention method for shoulder and knee range of motion.

목적 : 본 연구는 무릎관절 치환술 환자를 위한 작업치료 임상 가이드라인을 체계적으로 개발하고자 하였다. 전 세계적으로 무릎관절 치환술을 받은 환자들의 회복과 지역사회 복귀에 있어 작업치료의 역할이 매우 중요하다는 문헌이 보고되고 있으나, 우리나라에서는 관절 치환술 환자를 위한 작업치료가 거의 제공되지 않는다는 현실이 있다. 본 연구에서는 무릎관절 치환술 환자를 위한 근거기반 작업치료 중재를 확인하고 이것을 가이드라인을 통해 제안하고자 한다. 연구방법 : 가이드라인 개발 방법은 영국 작업치료사협회의 ｢Practice guideline development manual(4th edition)｣에서 소개한 절차를 따랐다. Patient/Population, Intervention, Comparison and Outcomes(PICO) 임상 질문 설정은 이해관계자의 의견을 수렴하여 한국의 보건·의료제도를 고려하여 설정하고 이를 바탕으로 체계적 고찰을 진행하였다. 데이터베이스에서 총 7,241건의 논문을 추출하였으며 논문의 질 평가 및 비평적 읽기를 통해 최종 66편의 근거 논문을 선정하였다. 논문의 중재를 바탕으로 가이드라인 내용을 구성하고 권고 강도는 Grading of Recommendations, Assessment, Development, and Evaluations(GRADE) approach 체계를 활용하여 [권고]와 [제안]으로 구분하였다. 결과 : 무릎관절 치환술 환자를 위한 작업치료 임상 가이드라인 권고 내용은 ‘환자 중심’과 ‘서비스 제공 중심’으로 범주화하였다. ‘환자 중심’범주에는 ‘일상생활 활동기능 향상’, ‘정신건강의 안정(불안, 우울 등)’, ‘환자 만족도 증가’, ‘지역사회복귀 향상’을, ‘서비스 제공 중심’범주에는 ‘작업치료사를 포함한 다학제 재활팀 구성’과 ‘작업치료 를 통한 병원 입원 기간 단축’을 위한 내용을 포함하였다. 결론 : 무릎관절 치환술 환자를 위한 작업치료 임상 가이드라인은 수술환자들의 안정적인 지역사회 복귀와 입원 기간 단축에 기여할 것이다. 또한 정형외과 작업치료사 역량 강화를 위한 교육자료로 활용될 수 있으며 의료비 용 감소를 위한 정책 마련에 근거 자료가 될 것이다.

Background: Virtual reality (VR) programs based on motion capture camera are the most convenient and cost-effective approaches for remote rehabilitation. Assessment of physical function is critical for providing optimal VR rehabilitation training; however, direct muscle strength measurement using camera-based kinematic data is impracticable. Therefore, it is necessary to develop a method to indirectly estimate the muscle strength of users from the value obtained using a motion capture camera. Objects: The purpose of this study was to determine whether the pedaling speed converted using the VR engine from the captured foot position data in the VR environment can be used as an indirect way to evaluate knee muscle strength, and to investigate the validity and reliability of a camera-based VR program. Methods: Thirty healthy adults were included in this study. Each subject performed a 15-second maximum pedaling test in the VR and built-in speedometer modes. In the VR speedometer mode, a motion capture camera was used to detect the position of the ankle joints and automatically calculate the pedaling speed. An isokinetic dynamometer was used to assess the isometric and isokinetic peak torques of knee flexion and extension. Results: The pedaling speeds in VR and built-in speedometer modes revealed a significantly high positive correlation (r = 0.922). In addition, the intra-rater reliability of the pedaling speed in the VR speedometer mode was good (ICC [intraclass correlation coefficient] = 0.685). The results of the Pearson correlation analysis revealed a significant moderate positive correlation between the pedaling speed of the VR speedometer and the peak torque of knee isokinetic flexion (r = 0.639) and extension (r = 0.598). Conclusion: This study suggests the potential benefits of measuring the maximum pedaling speed using 3D depth camera in a VR environment as an indirect assessment of muscle strength. However, technological improvements must be followed to obtain more accurate estimation of muscle strength from the VR cycling test.

Background: If the weakness of the knee muscles persists and there is pain at the same time, lumbar mobilization can be used. Objectives: This study investigated the immediate effect of lumbar joint mobilization on postural sway and knee pain in elite volleyball players. Design: Randomized controlled trial. Methods: Twelve male elite volleyball players were recruited for this study. Lumbar joint mobilization was performed in all study subjects. Evaluation items were static and dynamic balance and knee pain change. All evaluations were made immediately after the intervention. Results: C90 area, trace length, and STD Y deviation in the open static balance were significantly decreased after intervention (P<.05). C90 area, trace length, Velocity, STD X deviation, and STD Y deviation in static balance with closed eyes decreased significantly after intervention (P<.05). In dynamic balance, the left and right side. COPs were significantly increased. Pain significantly decreased after intervention (P<.05). Conclusion: This study found that lumbar joint mobilization is an effective method for improving postural sway and knee pain in elite volleyball players.

병렬영상기법인 SENSE 기법은 슬관절 자기공명영상의 검사 시간을 획기적으로 단축할 수 있다. 그러나 기법 적용 시 SENSE factor를 증가시키면 영상에 인공물의 발생이 증가하는 문제점이 있어 개선을 위해 본 연구에서는 최소의 시간이 소요되면서 인공물이 발생하지 않는 최적의 SENSE factor를 제시하고자 하였다. 연구 방법은 SENSE factor 1.0을 기준 으로 0.5 간격씩 5.0까지 변화시켜 팬텀 실험과 임상실험을 시행하였다. 3.0T 초전도 자기공명영상장치와 dS Knee 코일 을 사용하여 T1, T2 강조영상을 획득하였으며, 영상의 비교평가는 임상 경력 10년 이상의 방사선사 10명이 5점 척도로 평가한 후, 일원배치 분산분석과 사후분석을 통해 유의한 차이가 있는지 판단하였다. 연구 결과 팬텀 실험은 T1, T2 강조 영상 모두 SENSE factor를 1.5 이하로 하였을 때 기준 영상과 차이가 없었으며, 임상실험은 SENSE factor를 2.0 이하로 하였을 때 기준 영상과 차이가 없었다. 결론적으로 슬관절 자기공명영상 시 검사 시간을 단축하면서 인공물이 발생하지 않는 최적의 SENSE factor는 팬텀 실험의 경우 1.5, 임상실험의 경우 2.0이 적정하리라 사료된다.

Background: Pronated foot posture (PFP) contributes to excessive dynamic knee valgus (DKV). Although foot orthoses such as medial arch support (MAS) are widely and easily used in clinical practice and sports, few studies have investigated the effect of MAS on the improvement of DKV during stair descent in individuals with a PFP. Moreover, no studies reported the degree of improvement in DKV according to the severity of PFP when MAS was applied. Objects: This study aimed to examine the immediate effect of MAS on DKV during stair descent and determine the correlation between navicular drop distance and changes in DKV when MAS is applied. Methods: Twenty individuals with a PFP (15 males and five females) participated in this study. The navicular drop test was used to measure PFP severity. The frontal plane projection angle (FPPA) was calculated under two conditions, with and without MAS application, using 2-dimensional video analysis. Results: During stair descent, the FPPA with MAS (173.1° ± 4.7°) was significantly greater than that without MAS (164.8° ± 5.8°) (p < 0.05). There was also a significant correlation between the navicular drop distance and improvement in the FPPA when MAS was applied (r = 0.453, p = 0.045). Conclusion: MAS application can affect the decrease in DKV during stair descent. In addition, MAS application should be considered to improve the knee alignment for individuals with greater navicular drop distance.

본 연구는 무릎 MRI 검사 시 무릎의 위치가 보어 중심을 기준으로 거리가 멀어짐에 따라 무릎 연골 T2 값의 변화를 평가하고자 하였다. 이를 위해 무릎 질환이 없는 정상인 지원자 10명을 대상으로 하였고 보어 중심을 기준으로 무릎을 오른쪽으로 10 cm 그리고 20 cm 이동시키면서 영상을 획득하였다. 무릎 MRI 영상은 스핀에코기법을 활용하였고 무릎 연골의 T2 값을 계산하기 위해 TE 값은 13.8, 27.6, 41.4, 55.2, 그리고 69 ms로 적용하였다. 신호 측정은 무릎의 내, 외측 관절 융기가 가장 크게 나타난 영상의 대퇴 연골과 경골 연골에서 진행하였다. 연구의 결과, 재구성된 T2 값은 보어 중심에서 멀어질수록 감소하였다 (0 cm: 39.16 ms, 10 cm: 32.59 ms, 20 cm: 26 ms). 또한, 신호 값도 보어 중심에서 그 위치가 멀어질수록 감소하였다 (p<0.00). 특히, 보어 중심에서 20 cm까지 멀어짐에 따라 TE 69 ms의 영상에서 신호 값은 46.2%까지 감소하였다. 무릎 위치와 무릎 연골 T2 값의 상관관계분석 결과는 음의 상관관계 (r=-0.736)가 나타났다 (p<0.00). 결론적으로 MRI 검사에서 무릎 위치는 무릎 연골의 T2 값에 상당한 영향을 미치므로 T2 값의 정확도나 재현성 이 감소할 수 있다. 따라서 무릎 MRI 검사에서 무릎 연골의 정확한 T2 값을 획득하기 위해서는 최대한 보어 중심에서 검사가 이루어져야 한다.

Background: The superimposed technique (ST) involves the application of electrical muscle stimulation (EMS) during voluntary muscle action. The physiological effects attributed to each stimulus may be accumulated by the ST. Although various EMS devices for the quadriceps muscle are being marketed to the general public, there is still a lack of research on whether ST training can provide significant advantages for improving quadriceps muscle strength or thickness compared with EMS alone. Objective: To compare the effects of eight weeks of ST and EMS on the thicknesses of the rectus femoris (RF) and vastus intermedius (VI) muscles and knee extension strength. Methods: Thirty healthy subjects were recruited and randomly assigned to either the ST or EMS groups. The participants underwent ST or EMS training for eight weeks. In all participants, the thicknesses of the RF and VI muscles were measured before and after the 8-week intervention by ultrasonography, and quadriceps muscle strength was measured using the Smart KEMA tension sensor (KOREATECH Co., Ltd.). Results: There were significant differences in the pre- and post-intervention thicknesses of the RF and VI muscles as well as the quadriceps muscle strength in both groups (p < 0.05). RF thickness was significantly greater in the ST group (F = 4.294, p = 0.048), but there was no significant difference in VI thickness (F = 0.234, p = 0.632) or knee extension strength (F = 0.775, p = 0.386). Conclusion: EMS can be used to improve quadriceps muscle strength and RF and VI muscle thickness, and ST can be used to improve RF thickness in the context of athletic training and fitness.

Background: Bird dog exercise (BDE) is one of the lumbar stabilization exercises that rehabilitate low back pain by co-contraction of the local and global muscles. Previous studies have reported the effect of various type of BDEs (for example, practicing the exercises on various surfaces and changing the limb movement) for muscle co-contraction. Objects: This study aimed to investigate the effect of knee joint flexion position of the raised lower limb on abdominal and back muscle activity during BDE in patients with chronic low back pain (CLBP). Methods: Thirteen males participated in this study (age: 32.54 ± 4.48 years, height: 177.38 ± 7.17 cm). Surface electromyographic (SEMG) data of the internal abdominal oblique (IO), external abdominal oblique (EO), lumbar multifidus (MF), and thoracic part of the iliocostalis lumborum (ICLT) were collected in two knee joint flexion positions (90° flexion versus 0° flexion) during BDE. The SEMG data were expressed as a percentage of root mean square mean values obtained in the maximal voluntary isometric contraction. Results: Greater muscle activity of the IO (p = 0.001), MF (p = 0.009), and ICLT (p = 0.021) of the raised lower limb side and the EO (p = 0.001) and MF (p = 0.009) of the contralateral side were demonstrated in the knee joint flexion position compared to the knee joint extension position. Greater local/global activity ratios of the abdominal muscle (i.e., IO and EO) of the raised lower limb (p = 0.002) and the back muscle (i.e., MF and ICLT) of the contralateral side (p = 0.028) were also noted in the knee joint flexion position. Conclusion: BDE with a knee joint flexion position might be recommended as an alternative lumbar stabilization exercise to enhance muscle activity in both the raised lower limb and the contralateral sides of the trunk for individuals with CLBP

Background: Considering the kinetic chain of the lower extremity, a pronated foot position (PFP) can affect malalignment of the lower extremity, such as a dynamic knee valgus (DKV). Although the DKV during several single-leg movement tests has been investigated, no studies have compared the differences in DKV during a single-leg step down (SLSD) between subjects with and without PFP. Objects: The purpose of this study was to compare the DKV during SLSD between subjects with and without PFP. Methods: Twelve subjects with PFP (9 men, 3 women) and 15 subjects without PFP (12 men, 3 women) participated in this study. To calculate the DKV, frontal plane projection angle (FPPA), knee-in distance (KID), and hip-out distance (HOD) during SLSD were analyzed by twodimensional video analysis software (Kinovea). Results: The FPPA was significantly lower in PFP group, compared with control group (166.4° ± 7.5° and 174.5° ± 5.5°, p < 0.05). Also, the KID was significantly greater in PFP group, compared with control group (12.7 ± 3.9 cm and 7.3 ± 2.4 cm, p < 0.05). However, the HOD not significantly differed between two groups (12.7 ± 1.7 cm and 11.4 ± 2.5 cm, p > 0.05). Conclusion: The PFP is associated with lower FPPA and greater KID. When assess the DKV during SLSD, the PFP should be considered as a crucial factor for occurrence of DKV.

Background: Individuals with scapular winging may have proprioceptive dysfunction which is important for motor control and causes shoulder instability. Reduced serratus anterior (SA) and lower trapezius (LT) muscle activity accompanied by over-active upper trapezius (UT), and pectoralis major (PM) may be contributing factors. Flexi-bar (FB) exercise may be used to increase joint position sense (JPS) and alter the target muscle activities. Objects: This study aimed to investigate the immediate effects of flexi-bar exercise prior to knee push-up plus (FPK) versus knee push-up plus (KPP) on JPS and muscle activity of SA, LT, UT, and PM in subjects with scapular winging. Methods: Eighteen subjects with scapular winging were recruited. JPS was investigated at baseline, after KPP and after FPK. Passive and active JPS errors were calculated by isokinetic equipment. Surface electromyography was used to record muscle activities during KPP and FPK. One-way repeated-measures analysis of variance and post hoc analyses were used to analyze the JPS error measured at baseline, after KPP and after FPK. Paired t-tests were used to compare muscle activities between KPP and FPK. Results: Passive JPS error was significantly decreased after KPP (p = 0.005) and after FPK (p = 0.003) compared to the baseline. Active JPS error was also significantly decreased after KPP (p = 0.016) and after FPK (p = 0.012) compared to the baseline. There was no significant difference in the passive and active JPS errors between KPP and FPK. SA activity during FPK was significantly increased (p = 0.024), and LT activity during FPK was significantly increased (p = 0.006). There were no significant differences in the UT and PM activity. Conclusion: FB might be recommended to immediately improve passive and active JPS and to selectively increase SA and LT muscle activities during KPP in individuals with scapular winging.

Background: The foot is a complex body structure that plays an important role in static and dynamic situations. Previous studies have reported that altered foot posture might affect knee joint strength and postural stability, however their relationship still remains unclear. Objects: The purpose of this study was to identify whether pronated foot posture has an influence on knee isokinetic strength and static and dynamic postural stability. Methods: Forty healthy young males aged 18 to 26 years were included. Foot posture was evaluated using the Foot Posture Index-6 (FPI-6), and the subjects were divided into two groups according to their FPI-6 scores: a neutral foot group (n = 20, FPI-6 score 0 to +5) and a pronated foot group (n = 20, FPI-6 score +6 or more). Biodex Systems 3 isokinetic dynamometer was used to evaluate knee isokinetic strength and hamstring to quadriceps ratio at three angular velocities: 60°/sec, 90°/sec, and 180°/sec. The static and dynamic postural stability in a single-leg stance under the eyes-open and eyes-closed conditions were measured with a Biodex Balance System. Results: There were no significant differences between the groups in knee isokinetic strength and static postural stability (p > 0.05), but there was a significant difference in the medial– lateral stability index (MLSI) for dynamic postural stability under the eyes-closed condition (p = 0.022). The FPI-6 scores correlated significantly only with the dynamic overall stability index (OSI) and the MLSI (OSI: R = 0.344, p = 0.030; MLSI: R = 0.409, p = 0.009) under the eyesclosed condition. Conclusion: Participants with pronated foot had poorer medial–lateral dynamic stability under an eyes-closed condition than those without, and FPI-6 scores were moderately positively correlated with dynamic OSI and dynamic MLSI under the eyes-closed condition. These results suggest that pronated foot posture could induce a change in postural stability, but not in knee isokinetic strength.