scholarly journals Changes in intervertebral disc morphology persist 5 mo after 21-day bed rest

2011 ◽  
Vol 111 (5) ◽  
pp. 1304-1314 ◽  
Author(s):  
Daniel L. Belavý ◽  
P. Martin Bansmann ◽  
Gisela Böhme ◽  
Petra Frings-Meuthen ◽  
Martina Heer ◽  
...  
Keyword(s):  
Intervertebral Disc ◽  
Signal Intensity ◽  
Muscle Activation ◽  
Bed Rest ◽  
Intervertebral Discs ◽  
Erector Spinae ◽  
Cross Sectional ◽  
Intensity Changes ◽  
Lumbar Muscle ◽  
Muscle Cross Sectional Area

As part of the nutrition-countermeasures (NUC) study in Cologne, Germany in 2010, seven healthy male subjects underwent 21 days of head-down tilt bed rest and returned 153 days later to undergo a second bout of 21-day bed rest. As part of this model, we aimed to examine the recovery of the lumbar intervertebral discs and muscle cross-sectional area (CSA) after bed rest using magnetic resonance imaging and conduct a pilot study on the effects of bed rest in lumbar muscle activation, as measured by signal intensity changes in T2-weighted images after a standardized isometric spinal extension loading task. The changes in intervertebral disc volume, anterior and posterior disc height, and intervertebral length seen after bed rest did not return to prebed-rest values 153 days later. While recovery of muscle CSA occurred after bed rest, increases ( P ≤ 0.016) in multifidus, psoas, and quadratus lumborum muscle CSA were seen 153 days after bed rest. A trend was seen for greater activation of the erector spinae and multifidus muscles in the standardized loading task after bed rest. Greater reductions of multifidus and psoas CSA muscle and greater increases in multifidus signal intensity with loading were associated with incidence of low back pain in the first 28 days after bed rest ( P ≤ 0.044). The current study contributes to our understanding of the recovery of the lumbar spine after 21-day bed rest, and the main finding was that a decrease in spinal extensor muscle CSA recovers within 5 mo after bed rest but that changes in the intervertebral discs persist.

scholarly journals WISE 2005: Aerobic and resistive countermeasures prevent paraspinal muscle deconditioning during 60-day bed rest in women

2016 ◽  
Vol 120 (10) ◽  
pp. 1215-1222 ◽  
Author(s):  
Jacquelyn A. Holt ◽  
Brandon R. Macias ◽  
Suzanne M. Schneider ◽  
Donald E. Watenpaugh ◽  
Stuart M. C. Lee ◽  
...  
Keyword(s):  
Lower Body Negative Pressure ◽  
Bed Rest ◽  
Exercise Group ◽  
Erector Spinae ◽  
Paraspinal Muscle ◽  
Control Group ◽  
Cross Sectional ◽  
Before And After ◽  
Spine Function ◽  
Muscle Cross Sectional Area

Microgravity-induced lumbar paraspinal muscle deconditioning may contribute to back pain commonly experienced by astronauts and may increase the risk of postflight injury. We hypothesized that a combined resistive and aerobic exercise countermeasure protocol that included spinal loading would mitigate lumbar paraspinal muscle deconditioning during 60 days of bed rest in women. Sixteen women underwent 60-day, 6° head-down-tilt bed rest (BR) and were randomized into control and exercise groups. During bed rest the control group performed no exercise. The exercise group performed supine treadmill exercise within lower body negative pressure (LBNP) for 3-4 days/wk and flywheel resistive exercise for 2–3 days/wk. Paraspinal muscle cross-sectional area (CSA) was measured using a lumbar spine MRI sequence before and after BR. In addition, isokinetic spinal flexion and extension strengths were measured before and after BR. Data are presented as means ± SD. Total lumbar paraspinal muscle CSA decreased significantly more in controls (10.9 ± 3.4%) than in exercisers (4.3 ± 3.4%; P < 0.05). The erector spinae was the primary contributor (76%) to total lumbar paraspinal muscle loss. Moreover, exercise attenuated isokinetic spinal extension loss (−4.3 ± 4.5%), compared with controls (−16.6 ± 11.2%; P < 0.05). In conclusion, LBNP treadmill and flywheel resistive exercises during simulated microgravity mitigate decrements in lumbar paraspinal muscle structure and spine function. Therefore spaceflight exercise countermeasures that attempt to reproduce spinal loads experienced on Earth may mitigate spinal deconditioning during long-duration space travel.

scholarly journals Standing Up from a Chair with an Asymmetrical Initial Foot Position Decreases Trunk and Masticatory Muscle Activities in Healthy Young Men

Healthcare ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 480
Author(s):  
Youngsook Bae
Keyword(s):  
Muscle Activation ◽  
Young Men ◽  
Rectus Femoris ◽  
Erector Spinae ◽  
Masticatory Muscle ◽  
Cross Sectional ◽  
Upper Trapezius ◽  
Trunk Inclination ◽  
Trunk Kinematics ◽  
Foot Position

This study aimed to identify the activation of lower extremity, trunk, and masticatory muscle and trunk kinematics of the initial foot position during the sit-to-stand (STS) movement. Sixteen young men participated in this cross-sectional pilot study and performed STS using both symmetrical and asymmetrical foot positions. Activation of the tibialis anterior (TA), gastrocnemius lateral head (GA), rectus femoris (RF), biceps femoris (BF), rectus abdominis, erector spinae (ES), sternocleidomastoid (SCM), upper trapezius (UT), temporalis (TE), and masseter muscles in the dominant side was determined. For trunk kinematics, head and trunk velocities, front-back (For-Back) and mediolateral (Med-Lat) weight translation rates, and trunk inclination were measured. GA, TA, BF, and RF activation significantly increased, whereas ES, SCM, UT, and TE activation significantly decreased when using the asymmetrical foot position. Head velocity, For-Back, Med-Lat, and trunk inclination were also significantly decreased. In conclusion, the asymmetrical foot position increases muscle activation in the lower extremities and decreases trunk inclination. In addition, ES, UT, and TE muscle activity decreases at the initial asymmetrical foot position.

Countermeasures against lumbar spine deconditioning in prolonged bed rest: resistive exercise with and without whole body vibration

2010 ◽  
Vol 109 (6) ◽  
pp. 1801-1811 ◽  
Author(s):  
Daniel L. Belavý ◽  
Gabriele Armbrecht ◽  
Ulf Gast ◽  
Carolyn A. Richardson ◽  
Julie A. Hides ◽  
...  
Keyword(s):  
Whole Body Vibration ◽  
Bed Rest ◽  
Magnetic Resonance Images ◽  
Erector Spinae ◽  
Whole Body ◽  
Resistive Exercise ◽  
Body Vibration ◽  
Vibration Exercise ◽  
Quadratus Lumborum ◽  
Lumbar Muscle

To evaluate the effect of short-duration, high-load resistive exercise, with and without whole body vibration on lumbar muscle size, intervertebral disk and spinal morphology changes, and low back pain (LBP) incidence during prolonged bed rest, 24 subjects underwent 60 days of head-down tilt bed rest and performed either resistive vibration exercise ( n = 7), resistive exercise only ( n = 8), or no exercise ( n = 9; 2nd Berlin Bed-Rest Study). Discal and spinal shape was measured from sagittal plane magnetic resonance images. Cross-sectional areas (CSAs) of the multifidus, erector spinae, quadratus lumborum, and psoas were measured on para-axial magnetic resonance images. LBP incidence was assessed with questionnaires at regular intervals. The countermeasures reduced CSA loss in the multifidus, lumbar erector spinae and quadratus lumborum muscles, with greater increases in psoas muscle CSA seen in the countermeasure groups ( P ≤ 0.004). There was little statistical evidence for an additional effect of whole body vibration above resistive exercise alone on these muscle changes. Exercise subjects reported LBP more frequently in the first week of bed rest, but this was only significant in resistive exercise only ( P = 0.011 vs. control, resistive vibration exercise vs. control: P = 0.56). No effect of the countermeasures on changes in spinal morphology was seen ( P ≥ 0.22). The results suggest that high-load resistive exercise, with or without whole body vibration, performed 3 days/wk can reduce lumbar muscle atrophy, but further countermeasure optimization is required.

scholarly journals Rate of Muscle Activation in Power-and Endurance-Trained Boys

2011 ◽  
Vol 6 (1) ◽  
pp. 94-105 ◽  
Author(s):  
Cameron Mitchell ◽  
Rotem Cohen ◽  
Raffy Dotan ◽  
David Gabriel ◽  
Panagiota Klentrou ◽  
...  
Keyword(s):  
Muscle Activation ◽  
Peak Torque ◽  
Surface Emg ◽  
Knee Extension ◽  
Endurance Athletes ◽  
Group Differences ◽  
Electromechanical Delay ◽  
Cross Sectional ◽  
Isometric Knee Extension ◽  
Muscle Cross Sectional Area

Previous studies in adults have demonstrated power athletes as having greater muscle force and muscle activation than nonathletes. Findings on endurance athletes are scarce and inconsistent. No comparable data on child athletes exist.Purpose:This study compared peak torque (Tq), peak rate of torque development (RTD), and rate of muscle activation (EMG rise, Q30), in isometric knee extension (KE) and fexion (KF), in pre- and early-pubertal power- and endurance-trained boys vs minimally active nonathletes.Methods:Nine gymnasts, 12 swimmers, and 18 nonathletes (7–12 y), performed fast, maximal isometric KE and KF. Values for Tq, RTD, electromechanical delay (EMD), and Q30 were calculated from averaged torque and surface EMG traces.Results:No group differences were observed in Tq, normalized for muscle cross-sectional area. The Tq-normalized KE RTD was highest in power athletes (6.2 ± 1.9, 4.7 ± 1.2, 5.0 ± 1.5 N·m·s–1, for power, endurance, and nonathletes, respectively), whereas no group differences were observed for KF. The KE Q30 was significantly greater in power athletes, both in absolute terms and relative to peak EMG amplitude (9.8 ± 7.0, 5.9 ± 4.2, 4.4 ± 2.2 mV·ms and 1.7 ± 0.8, 1.1 ± 0.6, 0.9 ± 0.5 (mV·ms)/(mV) for power, endurance, and nonathletes, respectively), with no group differences in KF. The KE EMD tended to be shorter (P = .07) in power athletes during KE (71.0 ± 24.1, 87.8 ± 18.0, 88.4 ± 27.8 ms, for power, endurance, and nonathletes), with no group differences in KF.Conclusions:Pre- and early-pubertal power athletes have enhanced rate of muscle activation in specifically trained muscles compared with controls or endurance athletes, suggesting that specific training can result in muscle activation-pattern changes before the onset of puberty.

Finite Element Aided Tracking of Signal Intensity Changes in Deforming Intervertebral Disc Tissue

1998 ◽  
Vol 16 (1) ◽  
pp. 77-82 ◽  
Author(s):  
Idsart Kingma ◽  
Harrie Weinans ◽  
Jaap H. van Dieën ◽  
Ruud W. de Boer
Keyword(s):  
Finite Element ◽  
Intervertebral Disc ◽  
Signal Intensity ◽  
Disc Tissue ◽  
Intensity Changes

Muscle Activation in the Shoulder Girdle and Lumbopelvic-Hip Complex During Common Therapeutic Exercises

2021 ◽  
pp. 1-7
Author(s):  
Luk Devorski ◽  
David M. Bazett-Jones ◽  
L. Colby Mangum ◽  
Neal R. Glaviano
Keyword(s):  
Upper Extremity ◽  
Muscle Activation ◽  
Failure Surface ◽  
Deltoid Muscle ◽  
Shoulder Girdle ◽  
Erector Spinae ◽  
Cross Sectional ◽  
Maximum Voluntary Isometric Contraction ◽  
Therapeutic Exercises ◽  
External Oblique

Context: Lumbopelvic-hip complex (LPHC) exercises are used to increase stabilization within the human body. Torso-elevated side support (TESS), foot-elevated side support (FESS), prone bridge plank (PBP), and V-sit are common LPHC exercises. Objective: To evaluate muscle activation in the shoulder girdle and LPHC during 4 LPHC exercises and evaluate the reasoning for termination. Study Design: Cross-sectional study. Setting: Laboratory. Patients or Other Participants: Seventeen healthy participants (12 males and 5 females; age: 21.47 [3.16] y, height: 179.73 [8.92] cm, mass: 76.89 [11.17] kg). Main Outcome Measures: Participants completed 2 repetitions of the TESS, FESS, PBP, and V-sit until failure. Surface electromyography of the middle deltoid, latissimus dorsi, middle trapezius, rectus abdominis, erector spinae, external oblique, and gluteus medius were recorded and normalized to maximum voluntary isometric contraction (MVIC). The duration of exercise and subjective reasoning for termination of exercise was completed following the 4 tasks. Results: The TESS and PBP had significantly greater middle deltoid muscle activation (TESS: 55.66% [24.45%] MVIC and PBP: 42.63% [18.25%] MVIC) compared with the FESS (10.10% [10.04%] MVIC) and V-sit (2.21% [1.94%] MVIC), P < .05. The TESS produced significantly greater external oblique activity (78.13% [32.32%] MVIC) than the PBP (54.99% [19.54%] MVIC), P < .05. Due to shoulder fatigue and pain, 41.1% and 17.0% of participants terminated the TESS, respectively. The PBP was terminated due to abdominal fatigue (41.1%) and upper-extremity fatigue (47.0%). Conclusions: The V-sit resulted in isolated activity of the abdominal portion of the LPHC. The FESS had increased global co-contraction of the LPHC compared with the TESS. The PBP and TESS had significant muscle activation in the upper-extremity.

scholarly journals Ulnar Nerve Morphology in Magnetic Resonance Imaging Predicts Nerve Recovery After Surgery for Cubital Tunnel Syndrome

2020 ◽  
Author(s):  
Jong Seop Kim ◽  
Young Ju Chae ◽  
Gajendra Mani Shah ◽  
Hyun Sik Gong
Keyword(s):  
Magnetic Resonance Imaging ◽  
Ulnar Nerve ◽  
Signal Intensity ◽  
Cubital Tunnel Syndrome ◽  
Sectional Area ◽  
Resonance Imaging ◽  
Cross Sectional ◽  
Intensity Changes ◽  
Tunnel Syndrome ◽  
Poor Outcomes

Abstract Background: Magnetic resonance imaging (MRI) is helpful for the diagnosis of cubital tunnel syndrome (CuTS), but its prognostic value for surgical outcomes is unknown. We aimed to determine whether MRI parameters correlated with outcomes after surgery for CuTS. Methods: We reviewed 40 patients who had electrodiagnostic tests and MRIs for CuTS preoperatively and had 6-month evaluations postoperatively. The MRI parameters were ulnar nerve cross-sectional area (UNCSA) measured at 6 different levels around the medial epicondyle (ME), signal intensity changes of innervated muscles of the ulnar nerve, and the presence of ganglion around the ulnar nerve. Other factors assessed were age, symptom duration, symptom severity, presence of diabetes mellitus, and electrodiagnostic parameters including motor nerve conduction velocity (mNCV). We analyzed the factors associated with fair or poor outcomes graded by Wilson-Krout classification. Results: The UNCSA was the largest at ME level and smallest at 3cm distal to ME level. Increased ulnar nerve signal intensity changes were found in 34 subjects and increased forearm muscle signal intensity changes were found in two. Ten patients were found to have ganglia. Twelve patients (30%) had excellent results, 19 (48%) had good, 8 (20%) had fair, and 1 (4%) had a poor result. In univariate analysis, fair or poor outcomes were associated with increased UNCSA 1 cm proximal and 1 cm distal from the ME, the presence of ganglion, and decreased mNCV. In multivariate analysis, fair or poor outcomes were associated with either increased UNCSA 1 cm distal from the ME (OR 11.15; p = 0.019), or increased UNCSA 1 cm proximal from the ME (OR 16.01; p = 0.038) and decreased mNCV (OR 0.92; p = 0.044).Conclusions: This study demonstrated that increased ulnar nerve cross-sectional area on MRI correlated with suboptimal improvement after surgery for CuTS at 6 months follow up. MRI examination for morphologic changes of the ulnar nerve can be helpful for patient consultation on the prognosis of surgery for CuTS.

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