Background: Pectoralis minor tightness is associated with reduced glenohumeral internal rotation range of motion (ROM) and scapular anterior tilt alignment. However, the synergistic effects of the pectoralis minor stretching exercise and scapular posterior tilt strategy on glenohumeral internal rotation ROM and pectoralis minor length remain unexplored.
Objectives: This study examined the effects of doorway stretching with scapular posterior tilt on pectoralis minor length, scapular alignment, and glenohumeral internal rotation ROM.
Design: A case series study.
Methods: Fifteen adults with pectoralis minor tightness performed doorway stretching with scapular posterior tilt. Pectoralis minor length, acromion–table distance, and glenohumeral internal rotation ROM were measured before and immediately after stretching. The pectoralis minor length was calculated using the pectoralis minor index. The measured variables were analyzed using a paired t-test.
Results: While the pectoralis minor index and glenohumeral internal rotation ROM significantly increased, the acromion–table distance markedly decreased after doorway stretching with scapular posterior tilt (P<.05).
Conclusion: Based on the present findings, doorway stretching with scapular posterior tilt could be an effective exercise for increasing glenohumeral internal rotation ROM and pectoralis minor length.
Background: Shoulder external rotation exercises are commonly used to improve the stabilizing ability of the infraspinatus. However, during exercise, excessive activation of the posterior deltoid compared to the infraspinatus causes the humeral head to move anteriorly in an abnormal position. Many researchers have emphasized selective activation of the infraspinatus during shoulder external rotation exercise.
Objects: This study aims to delineate the optimal exercise method for selective activation of infraspinatus by investigating the muscle activities of the infraspinatus and posterior deltoid according to the four shoulder exercise methods and two forearm positions.
Methods: Thirty healthy individuals participated in this study. The participants were instructed to perform shoulder external rotation exercises following four exercise methods: sitting external rotation (SIER); standing external rotation at 90° abduction (STER); prone external rotation at 90° abduction (PRER); side-lying external rotation (SLER), and two forearm positions (neutral, supinated). The electromyography (EMG) signal amplitude was measured during each exercise. Surface EMG signals were recorded from the posterior deltoid, infraspinatus, and biceps brachii. Results: EMG results of the infraspinatus and posterior deltoid in PRER, were significantly higher than that of the other exercises (p < 0.01). The EMG ratio (infraspinatus/posterior deltoid) in SIER was significantly higher than that of the other exercises. EMG activation of the posterior deltoid in SIER, PRER, and SLER was significantly higher in neutral than in supinated (p < 0.01). Furthermore, the EMG of the infraspinatus in SIER was significantly higher in neutral than in supinated (p < 0.01). The EMG ratio (infraspinatus/ posterior deltoid) in SIER was significantly higher in neutral than in supinated (p < 0.05.) Contrarily EMG ratios in PRER and SLER were significantly higher in supinated than in neutral (p < 0.05).
Conclusion: The results show that clinicians should consider these exercise methods and forearm positions when planning shoulder external rotation exercises for optimal shoulder rehabilitation.
Background: Individuals with calf muscle shortening may have decreased dynamic balance. Objects: This study aimed to investigate the effect of mobilization with movement (MWM) and myofascial release (MFR) on kinematic changes in dynamic balance in individuals with calf muscle shortening.
Methods: Thirteen participants were randomly assigned to the MWM or the mobilization with movement added myofascial release (MWM-MFR) group. The MWM group received treatment with only MWM, whereas the MWM-MFR group was treated with MWM and MFR. Pre- and post-intervention passive range of motion (PROM), maximum reaching lengths, and modified star excursion balance test (MSEBT) results were compared for all participants. Wilcoxon signed-rank test and Mann-Whitney U test were used for statistical analysis.
Results: The results showed significant within-group differences in ankle PROM, but no significant between-group differences. The maximum reaching length in the MWM-MFR group in the posterolateral direction was significantly different before and after the intervention (p = 0.005). This group also showed significantly reduced ankle abduction in MSEBT during the posteromedial direction section 3 (p = 0.007) and posterolateral direction section 5 (p = 0.049) compared with the MWM group.
Conclusion: Combined MWM and MFR intervention improves ankle stability in the coronal plane during the posteromedial and posterolateral forward mo
Background: The serratus posterior inferior (SPI) muscle originates from the spinous process of T11-L2 and inserts at the lower border of the 9–12th ribs. This muscle is involved in thoracolumbar rotation and stability. Several positions can be used to improve trunk stability; the quadruped position is a good position for easily maintaining a neutral spine. In particular, during one arm lifting, various muscles act to maintain a neutral trunk position, and the SPI is one of these muscles. If trunk stability is weakened, uncontrolled trunk rotation may occur at this time. Tape can be used to increase trunk stability. There have been no studies on the effect of taping applied to the SPI muscle on thoracolumbar junction (TLJ) stability.
Objects: This study compared the TLJ rotation angle between three different conditions (without taping, transverse taping, and SPI muscle direction taping).
Methods: Thirty subjects were recruited to the study (18 males and 12 females). The TLJ rotation angle was measured during one arm lifting in a quadruped position (ALQP). Two taping methods (transverse and SPI muscle direction taping) were applied, and the TLJ rotation angle was measured in the same movement.
Results: SPI muscle direction taping significantly reduced TLJ rotation compared to that without taping (p < 0.001) and with transverse taping (p < 0.001). There was a significant difference in the TLJ rotation angle between transverse taping and SPI muscle direction taping (p < 0.017). Conclusion: SPI muscle direction taping reduces the TLJ rotation angle during ALQP. Therefore, SPI muscle direction taping is one method to improve TLJ stability and reduce uncontrolled TLJ rotation during ALQP.
Background: Although the scapular posterior tilt movement could facilitate the lower trapezius (LT) muscle activity, no study identified the effects of the scapular posterior tilt movement on the selective activation of the LT muscle during prone shoulder extension.
Objectives: To examine the influences of additional scapular posterior tilt on electromyography (EMG) of the upper trapezius (UT) and the LT muscles during prone shoulder extension.
Design: Cross-sectional study.
Methods: There were 15 asymptomatic male participants in this study who performed prone shoulder extension with and without scapular posterior tilt movements. For the scapular posterior tilt movements, participants performed visual biofeedback training for scapular movement using motion sensor. During the exercises, the EMG activity of the UT and LT was recorded using surface EMG system.
Results: The EMG activity of the LT significantly increased during prone shoulder extension with scapular posterior tilt compared to that of general prone shoulder extension, whereas that of the UT was not significantly different between the two exercises. Moreover, scapular posterior tilt application significantly decreased UT/LT muscle activity ratio.
Conclusion: Scapular posterior tilt movement may be emphasized during exercise when facilitating LT muscle activation.
Background: Forward head posture (FHP) causes various posture imbalances associated with the head and neck. Myofascial release is an effective treatment method used for relaxing muscles and reducing muscle hyperactivity, but no studies have been conducted on suboccipital and neck muscles related to FHP.
Objects: The purpose of this study was to investigate the immediate effect of roller massages on the cranio-cervical flexion (CCF) range of motion (ROM) and CCF strength applied to suboccipital and neck muscles in subject with forward head posture.
Methods: Twenty-four FHP subjects (male: 13, female: 11) were recruited for this study. All subjects were recruited with a craniovertebral angle (CVA) of 53 degrees or less and a head tilt angle (HTA) of 20.66 degrees or higher. CCF strength was measured using Pressure biofeedback unit (PBU) in the supine posture and CCF ROM was measured using smartphone-based inclinometer. Roller massage (RM) was applied to suboccipital and neck muscles for 2 minutes and CCF ROM and strength were remeasured.
Results: These results of this study showed that CCF ROM was a significant difference in CCF ROM before and after RM (p < 0.05). CCF strength also showed a significant difference before and after RM (p < 0.05).
Conclusion: RM method might be recommended to increase the immediate ROM and strength of CCF in subjects with forward head posture.
Background: Shoulder horizontal abduction in the prone position (SHAP) has been reported as an effective exercise to strengthen the lower trapezius. However, the effects of pre-emptive scapular posterior tilt on scapular muscle activity and scapulohumeral movements during SHAP have not been examined.
Objectives: To examine the effect of the addition of scapular posterior tilt on muscle activity of the trapezius and posterior deltoid, and scapular posterior tilt and shoulder horizontal abduction, during SHAP.
Design: Cross-sectional study.
Methods: Fifteen healthy male subjects performed two types of SHAP: general and modified SHAP (SHAP combined with pre-emptive scapular posterior tilt). To perform modified SHAP, pre-emptive scapular posterior tilt training was performed prior to the modified SHAP. Muscle activity of the middle and lower trapezius and posterior deltoid, and the amount of scapular posterior tilt and shoulder horizontal abduction, were measured during two types of SHAP.
Results: Muscle activity of the lower trapezius and scapular posterior tilt was significantly increased during the modified SHAP, while muscle activity of the posterior deltoid and the amount of shoulder horizontal abduction were significantly decreased. However, the middle trapezius muscle activity did not change during the modified SHAP.
Conclusion: The SHAP with pre-emptive scapular posterior tilt can be useful to strengthen the lower trapezius.
Background: Based on the understanding of the muscle activation relationship between the infraspinatus and posterior deltoid muscles to according to the angle of motion during external rotation on glenohumeral joint, effective shoulder joint strengthening exercise for the prevention and rehabilitation of shoulder injury due to muscle strength imbalance can be performed by achieving the ideal muscle activity ratio during exercise.
Objectives: To compare and analyze the muscle activation changes and activity ratio of the infraspinatus and posterior deltoid muscles according to the glenohumeral external rotation angle.
Design: Quasi-randomized trial.
Methods: The study included 48 healthy male and female adults who provided informed consent for participation in the study. All the subjects performed isometric glenohumeral external rotation by setting the angle of motion to 30°, 45°, and 60° using a 5 kg resistance weight pulley. On surface electromyography, the differences in muscle activation and activity ratio between the infraspinatus and posterior deltoid muscles were investigated.
Results: A significant difference in muscle activation was found in the comparison between the infraspinatus and posterior deltoid muscles according to the glenohumeral external rotation angle (P<.05). The muscle activation levels of the infraspinatus and posterior deltoid muscles were highest at the external rotation angles of 30° and 60°, respectively. The muscle activity ratio between the infraspinatus and posterior deltoid muscles also showed a significant difference (P<.05) and was highest at the shoulder external rotation angle of 30°.
Conclusion: The findings of this study suggest that muscle activity is the highest at the shoulder external rotation angle of 30° in healthy individuals.
Background: Posterior shoulder tightness, which is a problem mainly seen in patients with shoulder impingement syndrome, disrupts the scapulohumeral rhythm between the humerus and scapulae.
Objects: The aim of this study was to compare the effects of joint mobilization and stretching on shoulder muscle activity and internal rotation range of motion (ROM) of the glenohumeral joint in patients with impingement syndrome with posterior shoulder tightness.
Methods: The research subjects included 22 in-patients with impingement syndrome with posterior shoulder tightness. They were randomly divided into two groups: one group (12 patients) was treated with joint mobilization and the other group (10 patients) was treated with stretching for the posterior shoulder tightness. Each treatment was performed five times a week for two weeks, and there were 15 sessions for each treatment. The ROM of the internal rotation and muscle activities of shoulder joint were evaluated pretest and posttest in each group. Electromyography data were collected from the upper, middle, and lower trapezius and serratus anterior during shoulder abduction of 90°, 120°, and 150°.
Results: Both the joint mobilization and stretching groups showed significant decreases in muscle activity in the upper, middle, and lower trapezius on the posttest (p < 0.05). There was a significant difference in serratus anterior at 150° (p < 0.05), but there was no significant difference between group in post-hoc analysis (p > 0.025). The internal rotation ROM was significantly increased in the stretching group compared to that in the joint mobilization group (p < 0.025).
Conclusion: This study found that both joint mobilization and stretching for posterior shoulder tightness were effective in muscle activity during arm abduction, also in order to increase internal rotation ROM of shoulder joint, stretching was effective in patients with impingement syndrome with posterior tightness.
Background: Previous researchers have investigated the mechanical and neurophysiological effects of manual mobilization, however little research has been done on muscle tone and muscle stiffness.
Objective: To compare the effects of posterior-anterior (PA) mobilization with weight bearing on sling and conventional PA mobilization on the bed. Design: Randomized controlled trial (single blind)
Methods: The subjects were 16 male university students and randomized to sling mobilization group (SMG, n=8) or conventional mobilization group (CMG, n=8). SMG received PA mobilization using a sling and CMG received traditional mobilization on the bed during lumbar mobilization.
Results: Both left and right muscle tones of SMG increased, but left muscle tone of SMG were increased and right muscle tone was decreased after intervention. In addition, both left and right muscle stiffness of SMG were also increased, however left muscle stiffness of SMG was increased and right muscle stiffness was decreased. The muscle tone and muscle stiffness of SMG were higher than those of DMG, especially the right side was statistically significantly higher. Extension of SMG, extension and flexion of CMG were increased statistically significantly except for Flexion of SMG (p<.05). There were no significant differences between the groups in Extension and Flexion. Conclusions: This study suggests that lumbar spine PA mobilization using sling is beneficial in improving muscle tone, muscle stiffness, and trunk movement.
Background: Posterior-anterior (PA) vertebral mobilization, a manual therapy technique has been used for relieving pain or stiffness treating in spinal segment for in clinical practice, however evidence to gauge efficacy is yet to be synthesised.
Objects: This study aimed to investigate the effect of PA mobilization of the thoracic spine on the respiratory function in patients with low back pain (LBP).
Methods: The study participants included 30 patients with chronic LBP. They were randomly allocated to the experimental and control groups. The experimental and control groups received PA mobilization of the T1-T8 level of the thoracic spine and placebo mobilization, respectively. All patients received interventions for 35 minutes a day, five times a week, over 2-week period, respectively. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), forced expiratory flow 25∼75% (FEF25∼75%), and chest wall expansion were measured before and after the intervention. Statistical analysis was performed using independent t-test and two-way analysis of variance, and Pearson’s correlation analysis was used to compare the correlation between respiratory function and chest measurement.
Results: The experimental group showed significant improvements in FVC, FEV1, PEF, FEF25∼75% (p<.05), and chest wall expansion (p<.05) compared with the control group.
Conclusion: PA mobilization of the upper thoracic spine may be beneficial for improving respiratory function parameters including FVC, FEV1, PEF, FEF25∼75%, and chest wall expansion in patients with chronic LBP.
Background: Round shoulder posture, results from excessive flexed posture of the thorax, is defined as a position of scapular protraction, anterior tipping, and downward rotation. However, previous studies have focused on only passive position of the thorax during scapular posterior tilting (SPT) and have not reported on SPT combined with correction of flexed posture.
Objects: The aim of this study was to compare effects of SPT and SPT with prone trunk extension (SPT + PTE) on activities of the lower trapezius, serratus anterior, and thoracic erector spinae and degree of posture in subjects with round shoulder and flexed posture.
Methods: Fifteen subjects with round shoulder and flexed posture were recruited. The caliper was used to measure the degree of round shoulder and flexed posture. Electromyography was performed to collect data of muscle activities. Paired t-test was used to compare two exercise (α=.05).
Results: When SPT + PTE was applied, the degree of round shoulder posture (p=.001) and flexed posture (p=.039) significantly decreased compared with that when SPT was applied. The lower trapezius activity significantly increased in the SPT + PTE condition compared with that in the SPT condition (p=.026). There were no significant differences in serratus anterior activity between SPT + PTE and SPT. The thoracic erector spinae activity significantly increased in the SPT + PTE condition compared with that in the SPT condition (p=.014).
Conclusion: SPT + PTE might be one of the effective methods to enhance activities of lower trapezius and thoracic erector spinae, and to reduce round shoulder posture and flexed posture in subjects with round shoulder and flexed posture.
It has been reported that gastrocnemius tightness and posterior talar glide are crucial factors influencing ankle dorsiflexion. However, the relationship of ankle dorsiflexion and these factors is not identified in previous studies. The purpose of this study was to identify the relationship of ankle dorsiflexion passive range of motion and gastrocnemius tightness and posterior talar glide. Twenty-five male subjects participated in this study. Bilateral weight-bearing ankle dorsiflexion passive range of motion and amount posterior talar glide of participants were measured using an inclinometer. Change in myotendinous junction of medial gastrocnemius was measured using ultrasonography to identify gastrocnemius tightness. Pearson product moment correlations were performed to examine correlations between ankle dorsiflexion passive range of motion and gastrocnemius tightness and posterior talar glide. Present findings revealed significant correlation between ankle dorsiflexion passive range of motion and gastrocnemius tightness (p=0.017, r=0.336). Also, ankle dorsiflexion passive range of motion was correlated with posterior talar glide (p=0.001, r=0.470). The present findings provide experimental evidence for factors influencing weight-bearing ankle dorsiflexion.
“Cartilaginous choristoma” refers to as a tumorlike cartilaginous mass composed of normal tissues in an abnormal location. Oral cartilaginous choristomas are extremely rare. Although its rarity, most intraoral choristomas occur in the tongue. Adenomatoid hyperplasia of the minor salivary glands may be seen on the minor salivary gland bearing areas, especially seen on the palate. This report describes a case of firm mass on the left lateral tongue that was resulted cartilaginous choristoma associated with adenomatoid hyperplasia, which occurred in a 23-year-old male patient. And It hasn’t recurred during 17 months after complete excision.
This study investigated the effects of myofascial release therapy and massage on upper trapezius myalgia and sleep quality in 60 female and male individuals employed at casinos between the ages of 20-49. Subjects were divided into three groups: a myofascial release therapy group (n=20), a massage group (n=20), and a control group (n=20). Each intervention lasted 15 minutes and was performed 4 times a week for 4 weeks. Pain was significantly decreased after the application of myofascial release therapy and massage (p<.05), however slightly increased in the control group, and myofascial release therapy reduced pain a little more than massage. Sleep quality was also significantly increased by myofascial release and mass (p<.05), however only slightly in the control group. The findings of this study suggest that myofascial release therapy and massage are effective in improving upper trapezius myalgia and sleep quality in casino employees.
Background: Scapular posterior tilt (SPT) is important in the prevention of abnormal scapular movement and pain during elevation of the arm. However, previous studies have overlooked increased upper trapezius (UT) muscle activity interrupting the normal force couple of scapular motion and compensation of levator scapulae (LS) muscle activated simultaneously with UT during SPT exercise. Objects: The purpose of this study was to compare the effects of modified SPT with depression exercise versus SPT exercise on serratus anterior (SA), lower trapezius (LT), UT, and LS muscle activities and the clavicular tilt angle, in subjects with rounded shoulder posture (RSP) and myofascial pain in the UT muscle region. Methods: Eighteen subjects with RSP were recruited and randomly allocated to 2 groups; 9 in the SPT group and 9 in the SPT with depression group. All subjects met the specific RSP criteria and had myofascial pain of UT region. Depending on the allocated group, subjects performed the assigned SPT exercise and EMG data were recorded during the each exercise. Clavicular tilt angle was defined as the angle between the line joining the medial and lateral end of the clavicle and a horizontal line. Results: The SA muscle activity was significantly greater in SPT with depression than with SPT exercise (p<.05). The UT, LS muscle activity and the clavicular tilt angle was significantly lower in SPT with depression than with SPT exercise (p<.05). Conclusion: These findings were insightful because the potential risk of pain from overactivation of the UT and LS was considered, in contrast with SPT exercise. SPT with depression exercise can be implemented as an effective method to facilitate scapular muscle activity for stability and to prevent myofascial pain in the neck and shoulder.
목 적 : 후방십자인대는 무릎 관절의 안정화를 위한 중요한 인대로 인체의 균형을 유지하는데 매우 중요한 역할을 한다. 본 연구에서는 후방십자인대의 해부학적 구조에 따라 사방향 관상면 영상과 이중 사방향 시상면 영상을 획득하여 그 유용성을 평가하고자 한다.
대상 및 방법 : 2016년 12월부터 2017년 1월까지 환자 20명을 대상으로 검사하였고 SIEMENS사의 Skyra 3.0T에서 knee coil을 사용하였다. 검사 방법은 T2 COR, PD SAG을 획득하고 원위부 후방십자인대의 해부학적 구조를 고려한 PD OBL COR과 전체적인 구조를 고려한 PD Dual OBL SAG을 획득하였다. PCL의 관상면 비교를 위하여 밑단점의 길이와 폭을 측정하여 비교하였고, 시상면 평가를 위하여 기시점, 중간지점, 밑단점을 측정하여 비교하였다. 측정결과를 Mann-Whitney 방법을 사용하여 통계적 유의성을 검정하였다. 정성적 방법은 기존의 관상면, 시상면 영상과 사방향 관상면, 이중 사방향 시상면 영상에서 후방십자인대를 비교하여 미흡, 대등, 우월 세 단계로 평가하였다.
결 과 : 검사를 진행한 결과 기존 관상면 영상보다 사방향 관상면 영상에서 원위부 후방십자인대의 길이는4 7.9%, 폭 14.9% 증가하였고, 기존 시상면 영상보다 이중 사방향 시상면 영상에서 기시점 19.8%, 중간지점 18.3%, 끝단점 33%의 증가된 것 으로 측정되었다.
결 론 : 사방향 관상면 영상과 이중 사방향 시상면 영상 모두 기존 영상보다 우월한 영상 검사방법으로 평가되었다. 이에 슬 관절 후방십자인대의 해부학적 관찰에는 기존 검사 방법에 사방향 관상면 영상 검사와 이중 사방향 시상면 영상 검사를 병 행하는 것이 유용할 것으로 사료된다.
Background: In previous studies regarding flexible pes planus, Foot orthosis, special shoes have been used as interventions for correcting malalignment and intrinsic muscles strengthening exercise have been regarded as interventions for foot function and supporting medial longitudinal arch during walking. However, some recent studies reported that strengthening extrinsic muscles as well as intrinsic muscles is more effective and active intervention for flexible pes planus. In particular, the tibialis posterior muscle of foot extrinsic muscles plays essential roles in maintaining the medial longitudinal arch during dynamic weight bearing and balance. In addition this muscle acts longer than other supination muscles during the stance phase in the gait cycle.
Objects: This study aimed to investigate the effect of foot intrinsic muscle and tibialis posterior muscle strengthening exercise for plantar pressure and dynamic balance in adults with flexible pes planus.
Methods: 16 young flexible pes planus adults (7 males, 9 females) were recruited and were randomized into two groups. The experimental group performed foot intrinsic muscle and tibialis posterior muscle strengthening training, the control group performed only foot intrinsic muscle strengthening training. All groups received strengthening training for 30 minutes five times a week for six weeks.
Results: The experimental group had significantly lower plantar pressure of medial heel area than the control group in stand (p<.05). The experimental group had significantly higher dynamic balance ability than control group (p<.05).
Conclusion: The results of this study provide evidence to suggest that foot intrinsic muscle and tibialis posterior muscle of extrinsic muscle strengthening exercises may improve plantar pressure distribution and dynamic balance ability in adults with flexible pes planus.
목 적: 후방안내렌즈삽입술 후 이중경로방식(double-pass technique)으로 시력의 질을 평가하였다. 방 법: 중등도 및 고도 근시안(평균 등가구면굴절력: -9.26±1.67 D) 30명(57 안, 평균연령: 26.87± 7.26세)을 대상으로 후방안내렌즈 삽입 전과 삽입 1개월 후 OQAS(Optical Quality Analysis System) 장비 를 이용하여 MTF(modulation transfer function), Strehl ratio, OSI(objective scattering index) 및 객관 적 시력 OVs(OQAS values)를 측정하였다. 수술 전과 수술 1개월 후 모든 측정값을 비교하여 시력의 질을 평가하였으며, 중등도 근시안과 고도 근시군의 수술 후 시력의 질을 비교하였다.
결 과: 후방안내렌즈 삽입 1개월 후 MTF cutoff 값, Strehl ratio, OSI, OV100%, OV20% 및 OV9% 는 각 각 31.23±8.85 cycles/degree, 0.18±0.05, 0.76±0.37, 1.04±0.30, 0.73±0.24, 0.44±0.14로, MTF cutoff 값, Strehl ratio, OSI는 수술 전과 유의한 차이가 없었고(p=0.552, p=0.579, p=0.364), 객관적 시 력 OV100%, OV20%, OV9%도 후방안내렌즈 삽입 전과 유의한 차이를 보이지 않았다(p=0.561, p=0.671, p=0.522). 등가구면 굴절력 –6.00 D를 기준으로 나눈 두 그룹 사이에서 수술 1개월 후 MTF cutoff, Strehl ratio, OSI, OV100%, OV20% 및 OV9% 는 모두 유의한 차이를 보이지 않았다(p>0.05).
결 론: 후방안내렌즈 삽입 1개월 후 시력의 질을 나타내는 측정값은 수술 전 안경으로 교정한 시력의 질 과 비교하여 차이가 없었으며, 고도근시안에서도 중등도 근시안과 차이를 보이지 않아 굴절력에 관계없이 좋 은 시력의 질을 제공하는 것으로 평가된다.
Background: Prone hip extension (PHE) can be performed to measure the lumbopelvic motor patterns and motions. Imbalances in lumbopelvic muscle activity and muscle weakness can result in instability including pain in lumbopelvic region. The posterior oblique sling (POS) muscles contribute to dynamic lumbopelvic stability. In addition, POS are anatomically aligned with the trapezius muscle group according to shoulder positions. Objects: This study compared the electromyography (EMG) activity of POS and pelvic compensations during PHE with and without pre-activation of lower trapezius muscle (lowT). Methods: Sixteen healthy males were recruited. PHE was performed in randomized order: PHE with and without lowT pre-activation. Surface EMG signals were recorded for biceps femoris (BF), gluteus maximus (GM) (ipsilateral), lumbar multifidus (MF) (bilateral), and the lowT (contralateral). An electromagnetic tracking motion analysis was used to measure the angle of pelvic rotation and anterior tilting. Results: The ipsilateral GM and bilateral MF EMG amplitudes were greater during PHE with lowT pre-activation compared to PHE without lowT pre-activation (p<.05). The BF amplitude during PHE without lowT pre-activation was significantly greater than that during PHE with lowT pre-activation (p<.05). The angles of pelvic rotation and anterior tilting during PHE with lowT pre-activation were significantly smaller compared to PHE without lowT pre-activation (p<.05). Conclusion: PHE with lowT pre-activation, which is aligned with the POS, showed more increased MF and GM muscular activity with smaller lumbopelvic compensations in rotation and anterior tilting compared to PHE without lowT pre-activation.