Surface electromyography of lower limb muscles in healthy middle-aged and old women during stair ascent and descent / 中国康复理论与实践

ObjectiveTo observe the lower limb muscle activation strategy of healthy middle-aged and old women during stair ascent and descent with surface electromyography. MethodsFrom August, 2021 to February, 2022, 20 healthy middle-aged and old women were measured the surface electromyography root mean square (RMS) and integrated electromyography (iEMG) of bilateral vastus lateral, rectus femoris, vastus medialis, biceps femoris and semitendinosus during stair ascent and descent, and co-contraction ratio was calculated. ResultsDuring stair ascent, the RMS of bilateral vastus lateral, rectus femoris and vastus medialis was higher at starting stage than at following stage (|t| > 6.650, P < 0.001), while the RMS of biceps femoris and semitendinosus was lower (t > 3.559, P < 0.01); and the co-contraction ratio of hamstrings/quadriceps was lower at starting stage than at following stage (t > 8.185, P < 0.001). During stair descent, the RMS of bilateral vastus lateral, vastus medialis, biceps femoris and semitendinosus was higher at following stage than at starting stage (t > 2.345, P < 0.05), as well as the co-contraction ratio of hamstrings/quadriceps (t > 2.405, P < 0.05). ConclusionThe activities of the muscles around the knees are almost symmetrical during stair ascent and descent for healthy middle-aged and old women. The activation and co-contraction ratio of quadriceps and hamstring are various at starting/following stages.

Stair climbing and incident atrial fibrillation: a prospective cohort study

BACKGROUND@#A protective role for physical activity against the development of atrial fibrillation (AF) has been suggested. Stair climbing is a readily available form of physical activity that many people practice. Herein, we investigated the association between stair climbing and the risk of AF in a Japanese population.@*METHODS@#In this prospective cohort study, we used data of 6,575 people registered in the Suita Study, aged 30-84 years, and had no history of AF. The frequency of stair climbing was assessed by a baseline questionnaire, while AF was diagnosed during the follow-up using a 12-lead ECG, health records, check-ups, and death certificates. We used the Cox regression to calculate the hazard ratios and 95% confidence intervals of AF incidence for climbing stairs in 20-39%, 40-59%, and ≥60% compared with <20% of the time.@*RESULTS@#Within 91,389 person-years of follow-up, 295 participants developed AF. The incidence of AF was distributed across the stair climbing groups <20%, 20-39%, 40-59%, and ≥60% as follows: 3.57, 3.27, 3.46, and 2.63/1,000 person-years, respectively. Stair climbing ≥60% of the time was associated with a reduced risk of AF after adjustment for age and sex 0.69 (0.49, 0.96). Further adjustment for lifestyle and medical history did not affect the results 0.69 (0.49, 0.98).@*CONCLUSION@#Frequent stair climbing could protect from AF. From a preventive point of view, stair climbing could be a simple way to reduce AF risk at the population level.

Comparison of two circuit class therapy programs on walking capacity, gait velocity and stair ambulation among patients with chronic stroke: a parallel pretest-posttest pilot study

OBJECTIVE@#Circuit class therapy is a cost-efficient model of treatment that can be beneficial in a setting with limited resources. Current literature has conflicting results regarding which is a more effective approach to stroke rehabilitation: focusing on functional training or on improving impairments. This pilot study provides preliminary information comparing the effects of a task-oriented versus an impairment-focused circuit class therapy on walking ability among patients with chronic stroke.@*METHOD@#Eighteen participants with a single episode of chronic stroke and limited mobility were randomized into task-oriented circuit class (task group) (n=9) and impairment-focused circuit class (impairment group) (n=9). Both groups underwent intervention thrice a week for four weeks. Blind examination was done using the Ten Meter Walk Test for comfortable gait velocity (CGV) and fast gait velocit(FGV), Time Up and Down Stairs (TUDS), and Six Minute Walk Test (6MWT).@*RESULTS@#All participants completed the treatment sessions without adverse effects. After four weeks of treatment, the task group showed statistically significant within-group change in CGV (0.12±0.08, p=0.003) and FGV (0.25±0.22, p=0.007). The impairment group only showed statistically significant improvement in 6MWT (25.80±31.2, p=0.038). There were no statistically significant changes between the groups in all outcome measures.@*CONCLUSIONS@#The preliminary data from this pilot study suggest either program can improve walking-related outcomes and may not be different, although this needs to be confirmed using an appropriately-powered trial.

The predictive value of stair climbing test combined with arterial blood gas analysis on postoperative complications in lung cancer patients with limited pulmonary function / 中华胸心血管外科杂志

Objective:To evaluate the predictive value of stair climbing test combined with arterial blood gas analysis on postoperative complications in lung cancer patients with limited pulmonary function.Methods:A total of 1 231 hospitalized lung cancer patients with limited pulmonary function dating from August 2012 to August 2020 were retrospectively reviewed. Included in the cohort were 766 of patients who underwent stair climbing test(SCT) preoperatively and completed data collection. Patients were grouped according to their general condition, past medical history, surgical approach, pulmonary function test(PFT) and SCT results. Comparison of the postoperative cardiopulmonary complication rates were made between different groups, and independent risk factors were identified.Results:A total of 182 cardiopulmonary-related complications occurred in 144 cases, accounting for 18.8% of the entire cohort. Perioperative mortality rate was 0.9%(7/766). The rate of postoperative cardiopulmonary complications was significantly different between the groups stratified by gender, age, smoking index, PFT index(FEV1%, DLCO%), SCT results(height achieved, speed, changes in heart rate and oxygen saturation of the arteries before and after the test), ASA score, surgical approach(VATS/Open), resection range(Lobectomy/Sublobectomy), anesthetic duration, blood loss volume, etc. Logistic regression analysis showed that only height achieved( P<0.001), changes in heart rate( P<0.001), changes in oxygen saturation of the arteries( P=0.001), resection range( P=0.006) and anesthetic duration( P=0.025) were independent risk factors for cardiopulmonary-related complications in lung cancer patients with limited pulmonary function. Conclusion:The stair climbing test combined with arterial blood gas analysis could be used as a preoperative screening method for lung cancer patients with limited lung function and may have a predictive value for postoperative cardiopulmonary-related complications.

Surface Electromyography Characteristics of Lower Extremities of Flat Feet Walking on Stairs / 中国康复理论与实践

Objective:To explore the characteristics of surface electromyography (sEMG) of flat foot in lower extremity muscles when walking flat and stairs. Methods:From March to June, 2019, 20 male subjects (10 with normal feet, 10 with flat feet) were recruited to use sEMG system of Noraxon to collect the average amplitude and integral electromyography of sEMG of tibialis anterio (TA), medialis gastrocnemius (MG), lateralis gastrocnemius (LG), rectus femoris (RF) and biceps femoris (BF) during the flat ground walking and the stair walking. Results:As ascending stairs, the average amplitudes of TA, RF and BF of flat feet were higher than that of normal feet (|t| > 2.461, P < 0.05); as descending stairs, the average amplitude of MG of flat feet was higher (t = -1.976, P < 0.05), and the average amplitude of BF of flat feet was lower than that of normal feet (t = 2.298, P < 0.05). Compared with ground walking, the average amplitudes of TA, RF and BF of flat feet increased when ascending stairs (|t| > 2.257, P < 0.05), and the average amplitudes of RF and BF increased when descending stairs (|t| > 2.630, P < 0.05). As ascending stairs, the integral electromyography of TA, MG, LG, RF and BF of flat feet was higher than that of normal feet (|t| > 2.492, P < 0.01); as descending stairs, the integral electromyography of MG of flat feet was higher (t = -5.271, P < 0.05), and the integral electromyography of BF was lower (t = 2.685, P < 0.05) than that of normal feet. Compared with ground walking, the integral electromyography of TA, MG, LG and BF increased when ascending stairs (|t| > 2.088, P < 0.05), and the integral electromyography of TA, LG and RF decreased when descending stairs (t > 2.059, P < 0.05). Conclusion:The lower extremities muscles of flat foot compensate for the excessive rotation of the joint when walking stairs.

Changes in dynamic stability, motor coordination and joint mechanics of the lower extremity during stair descent and performing phone task / 中国组织工程研究

BACKGROUND: The coupling and coordination control of the multi-link rigid body of human body is the key to stable walking. It is reported that the use of cell phones greatly increases the chance of falling down stairs when walking; however, it lacks the analysis of the dynamic stability, motion coordination and joint mechanics of the lower limbs when walking down stairs with cell phone intervention. OBJECTIVE: To investigate the effects of cell phone on coupling control strategy of the multi-link rigid body in lower extremity during stair descent. METHODS: Twenty healthy university students were recruited and conducted the stair descent under no-interference (single task) and cell phone (phone task) randomly. Using the method of synchronous acquisition of 3D kinematics and dynamics, the kinetic and kinematic data were synchronously collected to acquire the parameters of stair descent under both conditions. RESULTS AND CONCLUSION: (1) The intervention of phone task significantly reduced the dynamic stability in anterior-posterior/media-lateral direction, the first knee extension moment peak, the first dorsiflexion moment peak, the second hip flexion moment peak in sagittal plane during stance phase, and significantly increased the mean and standard deviation of hip-knee/knee-ankle relative phase angles during swing phase. (2) It is concluded that when the gait of human body changes from time to time, the coupling control ability of multi-link rigid bodies decreased and the risk of falling increased. (3) The intervention of phone task reduces the supporting moment of lower limbs in the supporting phase, reduces the stability of adjacent joint coordination control in the swinging phase, reduces the dynamic stability in front, back and inside directions, and increases the risk of falling.

Effects of Electro-Acupuncture on Vertical Ground Reaction Force and Impulse Symmetry of Patients with Knee Osteoarthritis during Stair Climbing / 医用生物力学

Objective To observe the effects of electro-acupuncture on loading of lower limb joints in patients with knee osteoarthritis (KOA) during stair climbing and explore the related biomechanical mechanism. Methods Forty patients with KOA were randomly assigned, with 20 patients in observation group (electro-acupuncture group, EA group) and 20 patients in control group (superficial acupuncture group, SA group). Finally 18 patients in each group completed the study. In observation group, seven knee acupuncture points were chosen and patients were connected with electro-acupuncture instrument; while in control group, the electro-acupuncture instrument was connected but not electrified after superficial acupuncture at non-acupoint points. The three-dimensional gait analysis system was used to assess the biomechanical characteristics during stair climbing before and after treatment, including peak vertical force (PFz), vertical impulse (IFz) and symmetry index (SI%). Results After 3 weeks of treatment in EA group, PFz of the right foot during stair ascent and PFz of the left foot during stair descent increased (P＜0.05); IFz of both feet during stair ascent and IFz of the right foot during stairs descent significantly decreased (P＜0.05); no significant differences were found in SI% of peak and impulse (P＞0.05). In SA group, only SI of impulse during stairs ascent increased (P＜0.05). There was no significant difference between two groups before and after treatment (P＞0.05). Conclusions Electro-acupuncture can effectively improve the joint load capacity and reduce the dynamic cumulative load of patients w

Effects of Stair Climbing on Blood Pressure, Lipid Profiles, and Physical Fitness / 대한스포츠의학회지

PURPOSE: The purpose of the study is to identify the effects of worker's stair-climbing on blood pressure, lipid profiles, and physical fitness. METHODS: After recruiting 114 healthy adult women aged 20 to 64 years who have had sedentary for more than 3 months, we divided into two groups: the stair group (SG, n=57) and control group (CG, n=57). SG was supposed to do stair-climbing in daily life like workplace and home for 12 weeks. To investigate the effects of the lifestyle changing of stair-climbing, resting blood pressure, heart rate (HR), and lipid profiles were measured before and after 12-week stair-climbing. Also, physical fitness items such as peak oxygen consumption (VO2peak), back muscle strength, sit and reach, isokinetic strength of knee joint, static and dynamic balance were measured. RESULTS: As a result of the 12-week lifestyle changing of stair-climbing, resting systolic blood pressure (SBP; p < 0.05) and HR (p < 0.01) were significantly decreased in SG. Low-density lipoprotein-cholesterol (LDL-C) was significantly reduced in SG (p < 0.05). There was a significant improvement in the VO2peak (p < 0.001). There were a significant improvement in back strength (p < 0.001) and bilateral knee extensor (60°/sec: p < 0.05, p < 0.01, 180°/sec: p < 0.01, p < 0.01) and knee flexor (180°/sec: p < 0.01, p < 0.05) of isokinetic strength. There were significant improvements in static balance of one leg standing eye-closed (p < 0.05) and dynamic balance of left/right velocity (p < 0.01), forward/backward velocity (p < 0.01). CONCLUSION: In this study, 12 weeks of lifestyle changing of stair-climbing improved SBP, resting HR, LDL-C, VO2peak, back and knee strength, static and dynamic balance as well as increased physical activity volume of stair-climbing in the daily living.

Pelvic, Hip, and Knee Kinematics of Stair Climbing in People with Genu Varum

PURPOSE: This study examined the effects of the lower limb alignment on the pelvis, hip, and knee kinematics in people with genu varum during stair walking. METHODS: Forty subjects were enrolled in this study. People who had intercondylar distance ≥4cm were classified in the genu varum group, and people who had intercondylar distance < 4cm and intermalleolar distance < 4cm were placed in the control group. 3D motion analysis was used to collect the pelvis, hip, and knee kinematic data while subjects were walking stairs with three steps. RESULTS: During stair ascent, the genu varum group had decreased pelvic lateral tilt and hip adduction at the early stance phase and decreased pelvic lateral tilt at the swing phase compared to the control group. At the same time, they had decreased minimal hip adduction ROM at the early stance and decreased maximum pelvic lateral tilt ROM and minimum hip rotation ROM at the swing phase. During stair descent, the genu varum group had decreased pelvic lateral tilt at the early stance and decreased pelvic lateral tilt and pelvic rotation at the swing phase. In addition, they had decreased pelvic frontal ROM during single limb support and increased knee sagittal ROM during the whole gait cycle. CONCLUSION: This study suggests that a genu varum deformity could affect the pelvis, hip and knee kinematics. In addition, the biomechanical risk factors that could result in the articular impairments by the excessive loads from lower limb malalignment were identified.

Plantar Pressure and Surface EMG Parameters During Stair Walking / 医用生物力学

Objective To explore the plantar pressure and surface electromyography (sEMG) parameters during human stair walking, so as to provide theoretical support for foot structure design of dynamic walker, selection of power element and distribution of installation location. Methods Ten healthy young males were recruited to perform stair walking trials, respectively. The motion capture system, plantar pressure system and surface myoelectricity acquisition system were used to collect plantar peak pressure, trajectory of COP(center of pressure) and sEMG parameters of lower limb muscles at the same time. Results Compared with level walking, the percentage of stance time in the whole gait cycle increased during stair walking. The peak pressure of forefoot area increased during stair ascent, while the peak pressure of toe area decreased during stair descent. During stair walking, rectus femoris, biceps femoris, medialis and lateralis gastrocnemius played a main role in maintaining the stability of human body. Conclusions The plantar pressure distribution should be fully considered for foot structure design of dynamic walker and the function of main muscles should be considered for selection of power element and distribution of installation location.

Observation on impact of activity on knee meniscus with T1 rho and T2 mapping sequences / 中国医学影像技术

Objective To observe the impact of walking,running and stair activity on knee meniscus with T1 rho and T2 mapping sequences.Methods Twenty-three participants immediately after 30 minutes of rest,walking,running and stair activity underwent MRI scanning of the right knee,respectively.The 30 minutes rest was conducted before every physical activity.The physical activities were performed randomly to every participant in the morning every other week.T1 rho andT2 values of the meniscus in different physiological activities were estimated.Results T1 rho and T2 values reduced after physiological activities in posterior horn,body of medial meniscus and body of lateral meniscus compared with those of rest state (all P＜50.05).Compared with rest,reduction rate of T1 rho and T2 values of medial meniscus after different physiological activities reduced in the following order:Posterior horn ＞ body ＞ anterior horn,while those of lateral meniscus reduced in the following order:Body ＞ posterior horn ＞ anterior horn.Conclusion T1 rho and T2 mapping sequences are sensitive technologies to monitor the impacts of different activities on knee meniscus.

Finite element study on total knee prosthesis wear during stair ascent / 医用生物力学

Objective To study the effect of stair ascent on insert wear of total knee replacement (TKA) by finite element model, which is of great theoretical and practical significance for improvement of wear evaluation method and guidance of design of artificial knee joint prosthesis. Method A finite element analysis model of TKR wear based on Archard’s law was established and validated. The model was applied with loads under normal level walking (ISO14243) and stair ascent, respectively, to compare and analyze the influence of stair ascent on TKR wear. Results The predicted wear during level walking was consistent with experimental results reported in the literature. The volumetric wear rate during stair ascent was 37.10 mm3 per million cycles (MC), which was significantly higher than that during level walking (16.94 mm3/MC). The linear wear during stair ascent was significantly higher than that during level walking as well. Wear during stair ascent was mainly distributed in the backward area of medial platform, which was obviously different from that during level walking. Conclusions As a common daily activity with high loads and high flexion angles, stair ascent contributes an important part in TKR wear, and more attention should be paid to the testing and evaluation of TKR wear.

Surface Electromyography Changes of Vastus Medialis, Rectus Femoris and Vastus Lateralis during Stair Descent in Healthy Youth / 中国康复理论与实践

@#Objective To evaluate the activities of vastus medialis, rectus femoris and vastus lateralis during stair descent in healthy youth. Methods Thirty healthy college students were recruited from the Capital Medical University 2015 admissions in 2016. The electrode was put on the dominant side of the quadriceps. Surface electromyography was used to record muscle activity during stair descent. Results During stair descent, the maximum amplitude and mean amplitude were significantly lower in rectus femoris than in vastus medialis and vas-tus lateralis (P<0.001). No significant difference was found between vastus medialis and vastus lateralis (P>0.05). Conclusion The activa-tion of both vastus medialis and vastus lateralis during stair descent is significantly higher than that of rectus femoris. The coactivation of vastus medialis and vastus lateralis is equal in healthy youth.

Surface Electromyography Changes of Vastus Medialis, Rectus Femoris and Vastus Lateralis during Stair Descent in Healthy Youth / 中国康复理论与实践

@#Objective To evaluate the activities of vastus medialis, rectus femoris and vastus lateralis during stair descent in healthy youth. Methods Thirty healthy college students were recruited from the Capital Medical University 2015 admissions in 2016. The electrode was put on the dominant side of the quadriceps. Surface electromyography was used to record muscle activity during stair descent. Results During stair descent, the maximum amplitude and mean amplitude were significantly lower in rectus femoris than in vastus medialis and vas-tus lateralis (P<0.001). No significant difference was found between vastus medialis and vastus lateralis (P>0.05). Conclusion The activa-tion of both vastus medialis and vastus lateralis during stair descent is significantly higher than that of rectus femoris. The coactivation of vastus medialis and vastus lateralis is equal in healthy youth.

Kinetic mechanism of electroacupuncture for stair climbing in knee osteoarthritis patients / 中国针灸

<p><b>OBJECTIVE</b>To observe the kinetic change that reflects joint loading in different planes during stair climbing in knee osteoarthritis (KOA) after electroacupuncture (EA) by three-dimensional motion analysis, so as to provide reference for its biomechanical mechanism treated with acupuncture.</p><p><b>METHODS</b>Forty KOA patients, in accordance with the random number table, were assigned into an observation group and a control group, 20 cases in each one and finally 18 cases completed. Acupoints in the observation group were Neixiyan (EX-LE 4), Dubi (ST 35), Yanglingquan (GB 34), Yinlingquan (SP 9), Xuehai (SP 10), Liangqiu (ST 34) and Zusanli (ST 36); points in the control groups were located about 2 cm next to the above acupoints with shallow acupuncture. EA was connected at Neixiyan (EX-LE 4) and Yinlingquan (SP 9), Liangqiu (ST 34) and Yanglingquan (GB 34). The frequency was 2 Hz with continuous wave in the observation group and there was no current in the control group for the corresponding points. All the treatment was given for 3 weeks, totally 11 times. Climbing stairs gait was measured before and after treatment. Velocities and kinetic parameters during ascending and descending stairs were analyzed, including flexion and extension peak torques of hip, knee, ankle on the vertical plane, external knee adduction moment on the coronal plane.</p><p><b>RESULTS</b>After treatment in the observation group, velocities during ascending and descending stairs significantly increased (<0.05,<0.01); maximal ankle plantar flexor moments during ascending and descending stairs and the second peak external knee adduction moment (PEKAM2) during ascending stairs significantly increased (<0.05,<0.01). After treatment in the control group, the first peak external knee adduction moment (PEKAM1) and PEKAM2 during descending stairs were less than those before treatment (<0.05,<0.01). In the observation group, the difference value (DV) of velocity before and after treatment was positively correlated to DV in the torque of ankle plantar flexors during ascending stairs in the observation group (=0.598，<0.01). Excluding the impact of velocity, the DV of the maximal torque of ankle plantar flexors during ascending stairs didn't show difference in the observation group (>0.05).</p><p><b>CONCLUSION</b>EA can increase the velocities of ascending and descending stairs of KOA patients. It improves the loading capacity of knee joint on both sagittal and coronary planes. But its effect during ascending may be correlated with the increase of velocity. The mechanism of different effects between EA and minimal acupuncture on joint moments is still unclear and warrants further study.</p>

Variation characteristics of gait parameters during stair ascent and descent / 医用生物力学

Objective To collect the kinematics and kinetics functional parameters of healthy human lower limbs during stair ascent and descent, so as to provide data for designing the gait trajectory and selecting the driving components of the exoskeleton walker to achieve the motion of stair climbing. Methods Common staircase as an experimental setup was designed, and the three-dimensional (3D) motion capture system and 3D force plate were used to simultaneously measure the ankle, knee, hip motion information during stair ascent and descent. The movement characteristics of the lower limb during stair climbing was analyzed by SPSS statistical software and Origin graphics software, and the functional parameters during stair ascent and decent were also compared and analyzed. Results The joint angle at the sagittal plane, joint moment variation with gait and activity limits in lower limbs of healthy youth during stair ascent and descent were obtained by the experiment. The ranges of motion in ankle，knee and hip joints during stair ascent were -10.66°-13.26°, 6.85°-88.92°, 1.31°-50.18°,while those during stair descent were -37.42°-27.18°,9.83°-95.53°,8.01°-31.62°.The maximum ankle, knee and hip joint moment during stair ascent and descent were 1.788, 1.121, 0.946 N•m/kg, respectively. Conclusions The gait parameters variation with gait and the joint range of motion in human lower limb were significantly different during stair ascent and descent. Separate design targeting at stair ascent or stair descent is required for gait planning of walking aids, and the selection of driving element should consider the maximum moment in each joint during stair ascent and descent.

The influence of heel height on gait of young females during stair descent / 医用生物力学

Objective To investigate the effects of heel heights on gait of young women when going downstairs, and analyze the injury risk of women wearing high-heeled shoes during stair descent. Methods The gait from 17 young women wearing shoes with 4 different heel heights during their stair descent was measured by infrared high-speed motion capture system. The subjects’temporal parameters of gait and 3D joint angles of lower extremity were calculated and analyzed. Results Compared with flat shoes, the gait cycle increased when wearing 3 cm, 5 cm, 7 cm high-heeled shoes during stair descent, and the stance phase proportion and double-support stance phase proportion decreased, while the step width also decreased evidently. For 5 cm, 7 cm high-heeled shoes, the ankle range of motion (ROM) in the sagittal plane would reduce significantly, and for all the 3 cm, 5 cm, 7 cm high-heeled shoes, the ankle ROM in transverse plane would increase during stair descent. Wearing 3 cm, 5 cm high-heeled shoes could make the knee ROM in the sagittal plane significantly reduce, while wearing 3 cm, 5 cm, 7 cm high-heeled shoes, the knee ROM in the transverse plane would increase evidently. Wearing 5 cm, 7 cm high-heeled shoes, the maximum hip flexion angle was greater than that of wearing flat shoes, and the minimum hip flexion angle would be also greater when wearing 3 cm, 5 cm, 7 cm high-heeled shoes. Conclusions During stair descent, with the increase of heel heights, the gait cycle and swing phase proportion increase, while the stance phase proportion, double-support stance phase proportion and step width decrease, which will raise the risk of falling. Meanwhile, the knee and ankle ROMs in sagittal plane decrease gradually, while those in transverse plane come to increase. The research findings can help to further understand the influence of heel heights on gait characteristics and patterns during stair descent and provide reference for possible injury risk analysis.

Modified Mandibulotomy Technique to Reduce Postoperative Complications: 5-Year Results

PURPOSE: To review the 5-year outcomes of our modified mandibulotomy technique. Retrospective review of a tertiary level oral cancer center. MATERIALS AND METHODS: During a 5-year period, 30 patients who had a uniform surgical technique consisting of a lower lip-splitting, modified stair-step osteotomy with thin saw blade and osteotome after plate-precontouring and combination fixation with monocortical osteosynthesis (miniplate) and bicortical osteosynthesis (maxiplate and bicortical screws), with at least 14 months postoperative follow-up, were selected and reviewed retrospectively. RESULTS: There were 8 women and 22 men with an average age of 56.5 years. All the patients involved malignancies were squamous cell carcinoma. The main primary sites of the those who underwent a mandibulotomy were the tonsil, the base of tongue, the oral tongue, the retromolar pad area, and others. Others included buccal cheek, floor of mouth, and soft palate. 23 patients received postoperative radiation therapy, and among whom 8 patients also received chemotherapy. Total four (13%) mandibulotomy-related complications occurred, only two (6.7%) requiring additional operation under general anesthesia. CONCLUSION: Our modified mandibulotomy meets the criteria for an ideal mandibulotomy technique relatively well because it requires no intermaxillary fixation, can precise preserve the occlusion in a precise way, allows early function, requires no secondary procedures, and has few complications.

Effects of Abdominal Hollowing During Stair Climbing on the Activations of Local Trunk Stabilizing Muscles: A Cross-Sectional Study

OBJECTIVE: To examine using surface electromyography whether stair climbing with abdominal hollowing (AH) is better at facilitating local trunk muscle activity than stair climbing without AH. METHODS: Twenty healthy men with no history of low back pain participated in the study. Surface electrodes were attached to the multifidus (MF), lumbar erector spinae, thoracic erector spinae, transverse abdominus - internal oblique abdominals (TrA-IO), external oblique abdominals (EO), and the rectus abdominis. Amplitudes of electromyographic signals were measured during stair climbing. Study participants performed maximal voluntary contractions (MVC) for each muscle in various positions to normalize the surface electromyography data. RESULTS: AH during stair climbing resulted in significant increases in normalized MVCs in both MFs and TrA-IOs (p<0.05). Local trunk muscle/global trunk muscle ratios were higher during stair climbing with AH as compared with stair climbing without AH. Especially, right TrA-IO/EO and left TrA-IO/EO were significantly increased (p<0.05). CONCLUSION: Stair climbing with AH activates local trunk stabilizing muscles better than stair climbing without AH. The findings suggest that AH during stair climbing contributes to trunk muscle activation and trunk stabilization.

La ventilación no invasiva mejora los resultados en las pruebas de ejercicio en pacientes con enfermedad pulmonar obstructiva crónica / Non-invasive ventilation improves the outcome of exercise in COPD patients

Existen pocos estudios sobre el efecto de la Ventilación de doble nivel de presión positiva (VNI) sobre el ejercicio en pacientes con EPOC. El objetivo fue evaluar el impacto de la VNI en la respuesta a ejercicios máximos ysubmáximos en pruebas de campo en pacientes con EPOC. Fueron incluidos pacientes con EPOC (definición GOLD). Se les realizó una prueba de 6 minutos (según normativas de ATS), de escalera (Girish et al., Chest 2001) y ShuttleTest (Singh et al., Thorax 1992) con medición de escala de Borg de miembros inferiores y disnea, saturación arterial y frecuencia cardíaca. A través de una máscara nasal, se adaptó VNI con promedio 15 cmH2O de IPAP y 4 cmH2O de EPAP, y luego se realizaronlas mismas pruebas de ejercicio. Fueron evaluados 11 pacientes con EPOC: mediana edad: 61 años (IC25-75%, 58-75), sexo masculino 72%, FVC: 65% (IC25-75%, 60,1-70); FEV1: 37,4(IC25-75%, 33,97-42,5); FEV1/FVC: 46 (IC25-75%, 42,5-52,5); PaO2:68 mmHg (IC25-75%,63-75,3); PaCO2:40mmHg (IC25-75%,39-41).En la prueba de 6 minutos, se observó que la VNI aumentaba la distancia caminada en 61.78 % (p=0.001) la distancia caminada y la carga (kg.m) en 16,55% (p=0.002). No había cambios significativos en los síntomas (fatiga y disnea) por escala de Borg. En la prueba de escalera, se observó que la VNI incrementaba la velocidad de ascensoen 11,81% (p=0.05), sin cambios significativos en los síntomas o la altura ascendida. En el shuttle test, se observó que la VNI aumenta la distancia caminada en 30.6% (p=0.001), sin cambio significativos en los síntomas.En conclusión, se observó una significativa mejoría en las distancias caminadas y mayor velocidad de ascenso en la de escalera. Es la primera comunicación del efecto de la VNIsobre pruebas de escalera en pacientes con EPOC.

There are few exercise studies about the effect of bi-level non-invasive ventilation (NIV) on the exercise in COPD patients. The objective of the study was to evaluate the impact of NIV on the results of submaximal and maximal field exercise tests in COPD patients. The COPD patients were selected according to the GOLD definition. The study tests included: the six minute walking test (ATS guidelines), stair climbing test (Girish et al., Chest 2001) and shuttle test (Singh et al., Thorax 1992) which were measured with the Borg scale for legs and dyspnea, arterial saturation and heart rate. With a nasal mask, the NIV was adapted with pressure support ventilation through 15 cm H2O of IPAP and 4 cm H2O of EPAP. Then, the same exercise tests were performed. Eleven COPD patients were evaluated: age (median) 61 years (IC25-75%, 58-75), male sex 72%, FVC: 65% (IC25-75%, 60.1-70); FEV1: 37.4(IC25-75%, 33.97-42.5); FEV1/FVC: 46 (IC25-75%, 42.5-52.5); PaO2: 68 mmHg (IC25-75%,63-75.3); PaCO2: 40mmHg(IC25-75%, 39-41). The NIV increased the walked distance by 61.78% (p=0.001) and load (kg.m) by 16.55%(p=0.002) in the six minute walking test. There was no significant difference in the symptoms (dyspnea and fatigue) in the Borg scale. The NIV increased the ascent velocity by 11.81% (p=0.05) in the stair climbing test. No significant changes in symptoms and ascended height were observed. The NIV increased the walked distance by 30.6% (p=0.001), without significant changes in symptoms. As conclusion, distance increased significantly with NIV in the six minute walking test and shuttle test. A higher velocity was observed in the stair climbing test. This study was the first experience of NIV on the stair climbing test in COPD patients.