Less Pain, but no changes in maximal inclination angles during an overhead reach task following local anesthetic in patients with ongoing shoulder pain.

This multicenter observational study aimed to assess how pain reduction, induced by local anesthesia, affects the relative angular contributions of the shoulder girdle and trunk to the maximal angular performance during a semi-constrained overhead reach task in patients with ongoing shoulder pain. Twenty-nine individuals (age 59.0 SD 12.8 years;16-male) with symptomatic shoulders were administered corticosteroid and lidocaine injections by their attending orthopedic surgeon. Immediately before and after the injections, participants reached for a target on the ceiling ten times as high as possible while their pain levels, shoulder, and trunk movements were recorded. The analysis revealed that there was a significant reduction in pain following the injections. However, there were no significant differences in maximum shoulder and trunk inclination angles between the pre- and post-injection conditions. Notably, there were slight but statistically significant alterations in humeroscapular kinematics during the initial phase of arm elevation following the injections. In conclusion, acute pain relief following local anesthetics is not associated with immediate alterations in maximum shoulder girdle and trunk inclination angles during a semi-constrained overhead reach task in patients with ongoing shoulder pain. However, there are signs of small alterations in humeroscapular kinematics during the initial phase of arm elevation.

Understanding gait alterations: trunk flexion and its effects on walking neuromechanics.

Evolutionary and functional adaptations of morphology and postural tone of the spine and trunk are intrinsically shaped by the field of gravity in which humans move. Gravity also significantly impacts the timing and levels of neuromuscular activation, particularly in foot-support interactions. During step-to-step transitions, the centre of mass velocity must be redirected from downwards to upwards. When walking upright, this redirection is initiated by the trailing leg, propelling the body forward and upward before the foot contact of the leading leg, defined as an anticipated transition. In this study, we investigate the neuromechanical adjustments when walking with a bent posture. Twenty adults walked on an instrumented treadmill at 4 km/h under normal (upright) conditions and with varying degrees of anterior trunk flexion (10, 20, 30, and 40°). We recorded lower-limb kinematics, ground reaction forces under each foot, and the electromyography activity of five lower-limb muscles. Our findings indicate that with increasing trunk flexion, there is a lack of these anticipatory step-to-step transitions, and the leading limb performs the redirection after the ground collision. Surprisingly, attenuating distal extensor muscle activity at the end of stance is one of the main impacts of trunk flexion. Our observations may help to understand the physiological mechanisms and biomechanical regulations underlying our tendency toward an upright posture, as well as possible motor control disturbances in some diseases associated with trunk orientation problems.

Physiological and clinical effects of trunk inclination adjustment in patients with respiratory failure: a scoping review and narrative synthesis.

BACKGROUND: Adjusting trunk inclination from a semi-recumbent position to a supine-flat position or vice versa in patients with respiratory failure significantly affects numerous aspects of respiratory physiology including respiratory mechanics, oxygenation, end-expiratory lung volume, and ventilatory efficiency. Despite these observed effects, the current clinical evidence regarding this positioning manoeuvre is limited. This study undertakes a scoping review of patients with respiratory failure undergoing mechanical ventilation to assess the effect of trunk inclination on physiological lung parameters. METHODS: The PubMed, Cochrane, and Scopus databases were systematically searched from 2003 to 2023. INTERVENTIONS: Changes in trunk inclination. MEASUREMENTS: Four domains were evaluated in this study: 1) respiratory mechanics, 2) ventilation distribution, 3) oxygenation, and 4) ventilatory efficiency. RESULTS: After searching the three databases and removing duplicates, 220 studies were screened. Of these, 37 were assessed in detail, and 13 were included in the final analysis, comprising 274 patients. All selected studies were experimental, and assessed respiratory mechanics, ventilation distribution, oxygenation, and ventilatory efficiency, primarily within 60 min post postural change. CONCLUSION: In patients with acute respiratory failure, transitioning from a supine to a semi-recumbent position leads to decreased respiratory system compliance and increased airway driving pressure. Additionally, C-ARDS patients experienced an improvement in ventilatory efficiency, which resulted in lower PaCO2 levels. Improvements in oxygenation were observed in a few patients and only in those who exhibited an increase in EELV upon moving to a semi-recumbent position. Therefore, the trunk inclination angle must be accurately reported in patients with respiratory failure under mechanical ventilation.

Immediate Effect of Simulated High Heels on Pelvic and Spinal Posture in Healthy Young Subjects: A Cross-Sectional Study.

Background Investigations regarding the role of high-heeled shoes in the alteration of the spinopelvic profile attempted to identify a correlation with pain in the lower back. Conclusions from these studies, however, are controversial. In authors knowledge no studies were carried out to investigate the effect of heels on male population, which has been overlooked due to gender-related customs. Research question What is the immediate effect of the height of heels on the sagittal back profile (trunk inclination (TI), pelvic inclination, lordotic lumbar angle (ITL-ILS), kyphotic dorsal angle, lumbar arrow, and cervical arrow) in females and males, not used to wearing high-heeled shoes? Methods One hundred healthy young adult subjects were enrolled. Three were excluded. The remaining 97 subjects (48 female and 49 male) underwent a three-dimensional analysis of the posterior surface of the trunk, using rasterstereography. The spinopelvic profile in the barefoot condition, and with the heel raised by 3 and 7 cm, was recorded. To evaluate the reproducibility of the measure, the neutral evaluation was repeated twice in 23 subjects (13 males, 10 females). Results The change of heel height did not show statistically significant differences for any of the variables used; instead, significant differences were found stratifying the results according to the sex of the subjects tested. Test-retest evaluation in the neutral condition showed no significant differences using the Student's t-test (p > 0.05). Repeatability was excellent and significant for all data used (minimum TI r = 0.85, maximum ITL-ILS r = 0.97). Significance Studying the effect of heels on the spino-pelvic profile also in the male population is crucial for promoting gender-inclusive healthcare, enhancing occupational health practices and developing possible preventive measures. Nevertheless, in the sample of females and males evaluated in this study, the different heights of heel lift did not immediately induce significant changes in pelvis and spine posture. If there is therefore a correlation between low-back pain and the use of heels, it should not reasonably be sought in the immediate change of the spino-pelvic profile caused by raising the heels. However, the variables analyzed differed according to sex.

Influences of dynamic load phase shifts on the energetics and biomechanics of humans.

Using load-suspended backpacks to reduce vertical peak dynamic load exerted on humans can reduce metabolic costs. However, is it possible to further reduce metabolic cost by modulating dynamic load phase shift? If so, is anti-phase better than the others? In this study, we investigated the biomechanics, energetics and trunk response under phase shifts. Nine subjects wearing an active backpack with 19.4 kg loads walked on a treadmill at 5 km h-1 with four phase shift trials (T1-T4) and a load-locked trial (LK). Our results show that anti-phase trial (T3) assists ankle more and reduces the moment and gastrocnemius medialis activity, while T4 assists knee more and reduces the moment and rectus femoris activity. Due to the load injecting more mechanical energy into human in T3 and T4, the positive centre-of-mass work is significantly reduced. However, the gross metabolic rate is lowest in T4 and 4.43% lower than in T2, which may be because the activations of erector spinae and gluteus maximus are reduced in T4. In addition, T3 increases trunk extensor effort, which may weaken the metabolic advantage. This study provides guidance for improving assistance strategies and human-load interfaces and deepens the understanding of the energetics and biomechanics of human loaded walking.

PEEP Titration Is Markedly Affected by Trunk Inclination in Mechanically Ventilated Patients with COVID-19 ARDS: A Physiologic, Cross-Over Study.

BACKGROUND: Changing trunk inclination affects lung function in patients with ARDS. However, its impacts on PEEP titration remain unknown. The primary aim of this study was to assess, in mechanically ventilated patients with COVID-19 ARDS, the effects of trunk inclination on PEEP titration. The secondary aim was to compare respiratory mechanics and gas exchange in the semi-recumbent (40° head-of-the-bed) and supine-flat (0°) positions following PEEP titration. METHODS: Twelve patients were positioned both at 40° and 0° trunk inclination (randomized order). The PEEP associated with the best compromise between overdistension and collapse guided by Electrical Impedance Tomography (PEEPEIT) was set. After 30 min of controlled mechanical ventilation, data regarding respiratory mechanics, gas exchange, and EIT parameters were collected. The same procedure was repeated for the other trunk inclination. RESULTS: PEEPEIT was lower in the semi-recumbent than in the supine-flat position (8 ± 2 vs. 13 ± 2 cmH2O, p < 0.001). A semi-recumbent position with optimized PEEP resulted in higher PaO2:FiO2 (141 ± 46 vs. 196 ± 99, p = 0.02) and a lower global inhomogeneity index (46 ± 10 vs. 53 ± 11, p = 0.008). After 30 min of observation, a loss of aeration (measured by EIT) was observed only in the supine-flat position (-153 ± 162 vs. 27 ± 203 mL, p = 0.007). CONCLUSIONS: A semi-recumbent position is associated with lower PEEPEIT and results in better oxygenation, less derecruitment, and more homogenous ventilation compared to the supine-flat position.

Individuals with knee osteoarthritis demonstrate increased passive stiffness of the hip flexor muscles.

BACKGROUND: People with knee osteoarthritis stand and walk with increased trunk flexion. This altered postural alignment increases hamstring activation, elevating mechanical knee loads during walking. Increased hip flexor stiffness may lead to increased trunk flexion. Therefore, this study compared hip flexor stiffness between healthy individuals and individuals with knee osteoarthritis. This study also sought to understand the biomechanical effect of a simple instruction to reduce trunk flexion by 5° during walking. METHODS: Twenty individuals with confirmed knee osteoarthritis and 20 healthy individuals participated. The Thomas test was used to quantity passive stiffness of the hip flexor muscles and three-dimensional motion analysis used to quantify trunk flexion during normal walking. Using a controlled biofeedback protocol, each participant was then instructed to decrease trunk flexion by 5°. RESULTS: Passive stiffness was greater in the group with knee osteoarthritis (effect size = 1.04). For both groups, there was relatively strong correlation between passive stiffness and trunk flexion in walking (r = 0.61-0.72). The instruction to decrease trunk flexion produced only small, non-significant, reductions in hamstring activation during early stance. CONCLUSIONS: This is the first study to demonstrate that individuals with knee osteoarthritis exhibit increased passive stiffness of the hip muscles. This increased stiffness appears to be linked to increased trunk flexion and may therefore underlie the increased hamstring activation which is associated with this disease. As simple postural instruction does not appear to reduce hamstring activity, interventions may be required which can improve postural alignment by reducing passive stiffness of the hip muscles.

Projected frontal area and its components during front crawl depend on lung volume.

We examined the influence of lung volume on the vertical body position, trunk inclination, and projected frontal area (PFA) during swimming and the inter-relationships among these factors. Twelve highly trained male swimmers performed a 15 m front crawl with sustained maximal inspiration (INSP), maximal expiration (EXP), and intermediate (MID) at a target velocity of 1.20 m·s-1 . Using our developed digital human model, which allows inverse kinematics calculations by fitting individual body shapes measured with a three-dimensional photonic image scanner to individually measured underwater motion capture data, vertical center of mass (CoM) position, trunk inclination, and PFA were calculated for each complete stroke cycle. In particular, the PFA was calculated by automatic processing of a series of parallel frontal images obtained from a reconstructed digital human model. The vertical CoM position was higher with a larger lung-volume level (p < 0.01). The trunk inclination was smaller in INSP and MID than in EXP (p < 0.01). PFA was smaller with a larger lung-volume level (p < 0.01). Additionally, there was a significant interaction of vertical CoM position and trunk inclination with PFA (p = 0.006). There was a negative association between PFA and vertical CoM position, and a positive association between PFA and trunk inclination less than the moderate vertical CoM position (each p < 0.05). These results obtained using our methodology indicate that PFA decreases with increasing lung volume due to an increase in vertical CoM position, and additionally due to a decrease in trunk inclination at low-to-moderate lung-volume levels.

A two-stage disto-proximal braking modality to interrupt gait initiation in healthy adults.

The purpose of this investigation was to determine the effect of unexpected gait termination in able-bodied participants during gait initiation on spatiotemporal and stance limb biomechanical parameters. Twenty-one healthy adults took part in this study and were divided into two groups based on the natural anterior or posterior incline of their trunk. Each participant performed 15 random trials of gait initiation: 10 trials with a Go signal and 5 with Go-&-Stop signals. Spatiotemporal parameters were assessed between the Go signal and the first heel contact. Ankle, knee, and hip joint moments were calculated in the sagittal plane. Free moment and impulse were also calculated for the stance limb. Spatiotemporal parameters were not influenced by the mean trunk inclination (p > 0.05), but participants with a forwardly-inclined trunk presented higher hip extension moments (p < 0.05). Unexpected stopping required smaller ankle and knee moments compared to the Go condition (p < 0.05). The hip extension moments appeared to be independent of gait initiation conditions (p > 0.05). The capacity of able-bodied people to interrupt their gait initiation relied on a two-stage disto-proximal braking modality involving explosive motor patterns at the ankle and hip joints. Such a pattern could be altered in vulnerable people, and further studies are needed to investigate this. This study determined a clinical method applicable as a functional protocol to assess and improve the postural control of people suffering from a lack of motor modulation during crucial transient tasks. Such tasks are essential in activities of daily living.

Non-Invasive Neuromodulation in the Rehabilitation of Pisa Syndrome in Parkinson's Disease: A Randomized Controlled Trial.

Background: Pisa syndrome (PS) is a frequent postural complication of Parkinson's disease (PD). PS poorly responds to anti-parkinsonian drugs and the improvement achieved with neurorehabilitation tends to fade in 6 months or less. Transcranial direct current stimulation (t-DCS) is a non-invasive neuromodulation technique that showed promising results in improving specific symptoms in different movement disorders. Objectives: This study aimed to evaluate the role of bi-hemispheric t-DCS as an add-on to a standardized hospital rehabilitation program in the management of PS in PD. Methods: This study included 28 patients with PD and PS (21 men, aged 72.9 ± 5.1 years) who underwent a 4-week intensive neurorehabilitation treatment and were randomized to receive: i) t-DCS (t-DCS group, n = 13) for 5 daily sessions (20 min-2 mA) with bi-hemispheric stimulation over the primary motor cortex (M1), or ii) sham stimulation (sham group, n = 15) with the same duration and cadence. At baseline (T0), end of rehabilitation (T1), and 6 months later (T2) patients were evaluated with both trunk kinematic analysis and clinical scales, including UPDRS-III, Functional Independence Measure (FIM), and Numerical Rating Scale for lumbar pain. Results: When compared to the sham group, the t-DCS group achieved a more pronounced improvement in several variables: overall posture (p = 0.014), lateral trunk inclination (p = 0.013) during upright standing position, total range of motion of the trunk (p = 0.012), FIM score (p = 0.048), and lumbar pain intensity (p = 0.017). Conclusions: Our data support the use of neuromodulation with t-DCS as an add-on to neurorehabilitation for the treatment of patients affected by PS in PD.

The importance of the size of the trunk inclination angle in the early detection of scoliosis in children.

BACKGROUND: Early detection of idiopathic scoliosis is one factor in determining treatment effectiveness. Therefore, the aim of this study was to assess the importance of the size of the trunk inclination angle (ATI) for the early detection of scoliosis in preschool- and school-age children, taking into account the location and size of the spine curvature. METHODS: The study included a group of 216 children (mean age 11.54 years, standard deviation ± 3.05), who had previously untreated idiopathic scoliosis and a Cobb angle of ≥ 10°. The ATI values were compared with the corresponding Cobb angle values. The results of the ATI-Cobb correlation were compared to the ATI thresholds of 5° and 7°. RESULTS: In the age groups 6-9, 10-12 and 13-17 years, the method sensitivity for the ATI ≥ 7° criterion was low at 33.90%, 27.69% and 51.29% (p < 0.05), respectively, while for the ATI ≥ 5° criterion, it was 67.8%, 69.23% and 93.48% (p < 0.05), respectively. With respect to location, significantly more frequent misdiagnoses (p < 0.05) were related to the lumbar and thoracolumbar (regions) sections of the spine in the groups aged 6-9 and 10-12 for ATI ≥ 7°; while no significant relationship was found at ATI ≥ 5°. For both ATI levels, the most frequent cases of mis- or undiagnosed scoliosis were observed among children with a Cobb angle of 10°-14° (p = 0.004). CONCLUSION: A low predictive ATI value was demonstrated regarding scoliosis detection for the ATI 7° criterion in children aged 6-9 and 10-12 years, particularly for the lumbar and thoracolumbar locations. Adoption of the threshold of ATI 5° in screening tests for children aged 6-12 years, as well as for lower locations of scoliosis, may be more effective in the early detection of scoliosis. TRIAL REGISTRATION: This study was approved by the Jan Dlugosz University in Czestochowa Ethics Committee KE-U/7/2021, and conducted under the Declaration of Helsinki.

Lower lung-volume level induces lower vertical center of mass position and alters swimming kinematics during front-crawl swimming.

We examined the impact of lung-volume levels on the vertical center of mass (CoM) position and kinematics during submaximal front-crawl swimming at constant velocity. Thirteen well-trained male swimmers (21.2 ± 2.0 years) swam the front-crawl for 15 m at a target velocity of 1.20 m s-1 while holding one of three lung-volume levels: maximal inspiration (MAX), maximal expiration (MIN), and intermediate between these (MID). The three-dimensional positions of 25 reflective markers attached to each participant's body were recorded using an underwater motion capture system and then used to estimate the body's CoM. The swimming velocity and the vertical CoM position relative to the water's surface were calculated and averaged for one stroke cycle. Stroke rate, stroke length, kick rate, kick amplitude, kick velocity, and trunk inclination were also calculated for one stroke cycle. Swimming velocity was statistically comparable among the three different lung-volume levels (ICC [2,3] = 0.875). The vertical CoM position was significantly decreased with the lower lung-volume level (MAX: -0.152 ± 0.009 m, MID: -0.163 ± 0.009 m, MIN: -0.199 ± 0.007 m, P < 0.001). Stroke rate, kick rate, kick amplitude, kick velocity, and trunk inclination were significantly higher in MIN than in MAX and MID, whereas the stroke length was significantly lower (all P < 0.05). These results indicate that a lower lung-volume level during submaximal front-crawl swimming induces a lower vertical CoM position that is accompanied by a modulation of the swimming kinematics to overcome the increased drag arising from a larger projected frontal area.

The effect of tablet use on trunk posture while sitting.

BACKGROUND: The use of tablet during the office work is on the rise, but the biomechanical response of tablet use under various sitting postures is not well understood. OBJECTIVE: This study quantitatively measured changes in trunk kinematics under three sitting conditions (raised leg, neutral leg, and lowered leg) while using a tablet. METHODS: Fifteen participants were asked to sit on a chair with three different postures while staring at a handheld tablet or gazing straight ahead with a bare hand, and the head flexion, lumbar flexion and trunk inclination were captured with electrical goniometers. RESULTS: The results revealed significantly less lumbar flexion (12.8%) and trunk inclination (28.0%) while using the tablet compared to the empty hand condition (p < 0.001), but at a significant cost of increased head flexion (90.8%; p < 0.001). Further, while using the tablet, participants showed less head flexion in the raised leg condition (p < 0.001) than in the others (9.7% and 7.5%, respectively), but larger trunk inclination and lumbar flexion were required (p < 0.001 in both). CONCLUSIONS: Collectively, the lower extremity sitting posture significantly changed the way to observe the tablet by adopting more head flexion in neutral and lowered leg conditions or more trunk flexion in raised leg condition.

Effects of Toe Direction on Biomechanics of Trunk, Pelvis, and Lower-Extremity During Single-Leg Drop Landing.

CONTEXT: Toe direction is an important factor affecting knee biomechanics during various movements. However, it is still unknown whether toe direction will affect trunk and pelvic movements. OBJECTIVE: To examine and clarify the effects of toe directions on biomechanics of trunk and pelvis as well as lower-extremities during single-leg drop landing (SLDL). DESIGN: Descriptive laboratory study. SETTING: Research laboratory. PARTICIPANTS: A total of 27 male recreational-level athletes. INTERVENTION(S): Subjects performed SLDL under 3 different toe directions, including 0° (toe neutral), 20° (toe-in [TI]), and -20° (toe-out). SLDL was captured using a motion analysis system. Nondominant leg (27 left) was chosen for the analysis. MAIN OUTCOME MEASURES: Peak values of kinematic and kinetic parameters during landing phase were assessed. In addition, those parameters at the timing of peak vertical ground reaction force were also assessed. The data were statistically compared among 3 different toe directions using 1-way repeated measures of analysis of variance or Friedman χ2 r test. RESULTS: Peak knee abduction angle and moment in TI were significantly larger than in toe neutral and toe-out (P < .001). Moreover, peak greater anterior inclination, greater inclination, and rotation of trunk and pelvis toward the nonlanding side were seen in TI (P < .001). At the timing of peak vertical ground reaction force, trunk inclined to the landing side with larger knee abduction angle in TI (P < .001). CONCLUSIONS: Several previous studies suggested that larger knee abduction angle and moment on landing side as well as trunk and pelvic inclinations during landing tasks were correlated with knee ligament injury. However, it is still unknown concerning the relationship between toe direction and trunk/pelvis movements during landing tasks. From the present study, TI during SLDL would strongly affect biomechanics of trunk and pelvis as well as knee joint, compared with toe neutral and toe-out.

Real-time feedback to reduce low-back load in lifting and lowering.

Low-back pain (LBP) is a common health problem. Literature indicates an exposure-response relation between work-related lifting and LBP. Therefore, this study investigated effects of three kinds of real-time feedback on low-back load, quantified as lumbar moments, during lifting. We recruited 97 healthy male and female participants without a recent history of LBP and without prior biomechanical knowledge on lifting. Participants were assigned to groups based on the time of enrollment, filling the four groups in the following order: moment feedback, trunk inclination angle feedback, lumbar flexion feedback, and a control group not receiving feedback. Feedback was given by a sound when a threshold level of the input variable was exceeded. Participants were unaware of the input variable for the feedback, but were instructed to try to avoid the audio feedback by changing their lifting strategy. The groups with feedback were able to reduce the audio feedback and thus changed the input variable towards a more desired level. Lumbar moments significantly decreased over trials in the inclination and moment feedback groups, remained similar in the lumbar flexion group and increased in the control group. Between group comparisons revealed that low-back load was significantly lower in the moment and inclination groups compared to the control group. Additionally, moments were lower in the inclination group than in the lumbar flexion group. Real-time feedback on moments or trunk inclination is a promising tool to reduce low-back load during lifting and lowering.

Decreased Vertical Trunk Inclination Angle and Pelvic Inclination as the Result of Mid-High-Heeled Footwear on Static Posture Parameters in Asymptomatic Young Adult Women.

The influence of high-heel footwear on the lumbar lordosis angle, anterior pelvic tilt, and sacral tilt are inconsistently described in the literature. This study aimed to investigate the impact of medium-height heeled footwear on the static posture parameters of homogeneous young adult standing women. Heel geometry, data acquisition process, as well as data analysis and parameter extraction stage, were controlled. Seventy-six healthy young adult women with experience in wearing high-heeled shoes were enrolled. Data of fifty-three subjects were used for analysis due to exclusion criteria (scoliotic posture or missing measurement data). A custom structured light surface topography measurement system was used for posture parameters assessment. Three barefoot measurements were taken as a reference and tested for the reliability of the posture parameters. Two 30-degree wedges were used to imitate high-heel shoes to achieve a repeatable foot position. Our study confirmed the significant (p < 0.001) reduced vertical balance angle and pelvis inclination angle with large and medium-to-large effects, respectively, due to high-heel shoes. No significant differences were found in the kyphosis or lordosis angles. High-heeled shoes of medium height in young asymptomatic women can lead to a straightening effect associated with a reduced vertical balance angle and decreased pelvic inclination.

Trunk flexion during walking in people with knee osteoarthritis.

BACKGROUND: Over 50% of the body's mass is concentrated within the head, arms and trunk. Thus, small deviations in the orientation of the trunk, during normal walking, could influence the position of the centre of mass relative to the lower limb joint centres and impact on lower limb biomechanics. However, there are minimal data available on sagittal kinematics of the trunk in people with knee osteoarthritis (OA) during walking. RESEARCH QUESTION: Do people with knee OA have altered kinematic patterns of the trunk, pelvis or hip compared with healthy control participants during walking? METHODS: Statistical parametric mapping was used to compare sagittal and frontal plane kinematic patterns, during walking, between a healthy group and cohort of people with knee OA. RESULTS: Individuals with knee OA walked with a mean increase in trunk flexion of 2.6°. Although this difference was more pronounced during early stance, it was maintained across the whole of stance phase. There were no differences, between the groups, in sagittal plane pelvic or hip kinematics. There were also no differences in trunk, pelvic or hip kinematics in the frontal plane. SIGNIFICANCE: Most previous gait research investigating trunk motion in people with knee OA has focused on the frontal plane. However, our data suggest that an increase in sagittal trunk flexion may be a clinical hallmark of people with this disease. Altered trunk flexion could affect joint moments and muscle patterns and therefore our results motivate further research in this area.

Detection of daily postures and walking modalities using a single chest-mounted tri-axial accelerometer.

This study presents a novel method for the detection and classification of a wide range of physical activities, including standing, sitting, lying, level walking, and walking upstairs and downstairs using a single chest-mounted accelerometer. The trunk inclination angle and variation of the gravitational component of the accelerometer recording were used for detection and classification of postural transitions and walking modalities. In addition, biomechanical features of each transition were used to reject false detections. To validate the accuracy of the presented method, two studies were performed, first in the (1) laboratory environment, where a motion capture system was the reference system (ten healthy subjects), and second (2) in the free-living environment where a handheld camera was the reference system (ten healthy subjects). The first study showed that the proposed method obtained higher accuracy, sensitivity, and specificity in detection of postural transitions and walking modalities compared to other methods in the literature when implemented on the same dataset. The second study obtained (1) the sensitivity and specificity of 100% for detection of sit-to-lie, lie-to-sit, and stand-to-sit, and 100% and 97%, respectively, for detection of sit-to-stand, and (2) the accuracy of 99%, 99%, and 95% for detection of slow, normal, and fast level walking, and 97% and 96% for detection of walking upstairs and downstairs. The proposed method enabled detection and classification of postural transitions and walking modalities with high sensitivity and specificity using only one chest-mounted accelerometer. This approach can be used for convenient and reliable assessment of physical activities in long-term.

Truncal changes in children with mild limb length inequality: a surface topography study.

BACKGROUND: Limb length Inequality (LLI) in children and adults may affect posture, gait, and several truncal parameters, and it can cause spinal scoliosis. In literature, however, there is a paucity of assessment of truncal and spinal changes due to mild LLI in children. This report presents children with LLI, and it aims to provide information in pelvic imbalance, spinal posture, and scoliotic curve, using surface topography analysis which is a novel methodological approach for this condition. STUDY DESIGN: This is an ongoing prospective research study on patient series suffering LLI. MATERIAL AND METHOD: Twenty children, attending the Scoliosis Clinic of the department, 7 boys, 13 girls, 9-15 years old, range 7.5-15, mean 15.5 years, having mild LLI, were assessed. The LLI was 0.5 to 2 cm, mean 1.2 cm. There was not any post-traumatic LLI. We evaluated the LLI in correlation to pelvic and spinal posture parameters. The 4D Formetric DIERS apparatus (4DF) was used for the surface topography assessment. The following were assessed: in the coronal plane, the coronal imbalance, the pelvic obliquity, the lateral deviation, and the 4DF scoliosis angle; in the sagittal plane, the sagittal imbalance, the 4DF kyphotic angle, the kyphotic apex, the 4DF lordotic angle, the lordotic apex, the pelvic tilt, and the trunk inclination; and in the transverse plane, the pelvis rotation, the pelvic torsion, the surface rotation, and the 4DF vertebral rotation. LLI was measured using a tape. The data were statistically analyzed, and reliability study for the LLI was also performed. RESULTS/DISCUSSION: The LLI was statistically significantly correlated to the 4DF reading of pelvis rotation, pelvic tilt (pelvic obliquity), and surface rotation. The scoliometer readings (angle trunk rotation ATR or trunk inclination ATI) in the lumbar region were statistically significantly correlated to the 4DF readings of pelvic tilt (pelvic obliquity). The normally symmetric truncal parameters were also statistically significantly changed (all these deviating from the line of gravity through the vertebral prominence). Interestingly, LLI was not correlated to the scoliosis angle and the scoliometer reading at the lumbar level.The following 4DF readings are presented: in the coronal plane, the coronal imbalance, pelvic obliquity, lateral deviation, and 4DF scoliosis angle; in the sagittal plane, the sagittal imbalance, kyphotic angle, kyphotic apex, lordotic angle, lordotic apex, pelvic tilt, and trunk inclination; and in the transverse plane, the pelvic rotation, pelvic torsion, surface rotation, and vertebral rotation. CONCLUSIONS: Previous studies have reported the results after simulation of LLI in order to evaluate the effects on the pelvic balance and spinal posture parameters. This report is not a LLI simulation study but it presents the effects of mild LLI on truncal changes in the main cardinal planes in children suffering LLI. These changes undoubtedly affect not only the standing truncal posture but also the gait's economy as well.As mild LLI affects the pelvic balance and spinal posture parameters, our therapeutic approach is that mild LLI (less than 2.0 cm) has to be corrected using shoe elevation, in order to equalize the pelvic obliquity and, consequently, the spinal posture parameters.