Variation of muscle moment arms with elbow and forearm position

Murray, Wendy M.; Delp, Scott L.; Buchanan, Thomas S.

doi:10.1016/0021-9290(94)00114-j

Cited by 315 publications

(267 citation statements)

References 15 publications

Supporting

Mentioning

229

Contrasting

Unclassified

Order By: Relevance

“…Significant effects of the elbow angles on maximum torque production have been reported when the forearm is positioned at 75% pronation and the elbow is flexed at 135º 13 . also, it has been reported that supination peak torque occurs when the elbow is flexed at 85º and goes down to 48% when the elbow is flexed at 45º 21 .…”

Section: Discussionmentioning

confidence: 95%

“…in literature, there are reports that the production of maximum forearm supination torque is influenced by elbow position and that the greatest torque-generating capacity occurs in the positions in which the elbow is at greater flexion angles, decreasing as the elbow extends [11][12][13] . the effect on the capacity for maximum supination torque production has been described in literature; however there is no record, up to the present date, of studies on the effects of elbow position on submaximum torque control.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Efeito da posição da articulação do cotovelo no controle de torque de supinação do antebraço em jovens adultos

Borges¹,

Rodrigues²,

Loss³

et al. 2007

Rev. bras. fisioter.

View full text Add to dashboard Cite

Background: large numbers of cases of pathological conditions in the forearm and elbow that have been reported in the literature are associated with tasks involving effort and repetitive movements of the arms and hands. Elbow position is known to affect the production of maximum forearm supination torque, and is a critical factor in designing appropriate therapeutic exercises. However, to our knowledge, there are no data on the effects of elbow position on tasks requiring control over submaximal torque levels. objective: this study investigated the effects of elbow position on the production of maximum isometric forearm supination torque, and on constant and continuous torque control at different submaximal torque levels. method: Sixteen young adults (24.7 ± 2.2 years old) were asked to perform two tasks: production of maximum lateral pinch torque (thumb and index finger) and controlled lateral pinch constant torque. Both tasks were evaluated at four different elbow positions (free position, 0°, 45° and 90° of elbow flexion) and three submaximal levels of lateral pinch torque production (20%, 40% and 60%). maximal torque, variability, irregularity and accuracy of the motor response were used as dependent variables. Results: greater torque values were found when the elbow joint was not restricted. the torque control tasks were not affected by the elbow position. However, greater variability and irregularity and lower accuracy in torque response were recorded with progressively increased submaximal torque levels. Conclusion: the results suggest that elbow position is not a determining factor for rehabilitation exercises that include torque control, in relation to forearm supination.

show abstract

Section: Discussionmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

Efeito da posição da articulação do cotovelo no controle de torque de supinação do antebraço em jovens adultos

Borges¹,

Rodrigues²,

Loss³

et al. 2007

Rev. bras. fisioter.

View full text Add to dashboard Cite

show abstract

“…During the electrogoniometric recording of elbow flexion, the B3 prototype produced the ranges of motion with the greatest biomechanical advantage (80° to 120°) 30 for all of the handling heights we evaluated. This result was expected because the higher handle position favors elbow flexion.…”

Section: Discussionmentioning

confidence: 99%

30o inclination in handles of plastic boxes can reduce postural and muscular workload during handling

Silva

Oliveira

Silva

et al. 2013

Braz. J. Phys. Ther.

View full text Add to dashboard Cite

| Background: The handling of materials, which occurs in the industrial sector, is associated with lesions on the lumbar spine and in the upper limbs. Inserting handles in industrial boxes is a way to reduce work-related risks. Although the position and angle of the handles are significant factors in comfort and safety during handling, these factors have rarely been studied objectively. Objective: To compare the handling of a commercial box and prototypes with handles and to evaluate the effects on upper limb posture, muscle electrical activity, and perceived acceptability using different grips while handling materials from different heights. Method: Thirty-seven healthy volunteers evaluated the handles of prototypes that allowed for changes in position (top and bottom) and angle (0°, 15°, and 30°). Wrist, elbow, and shoulder movements were evaluated using electrogoniometry and inclinometry. The muscle electrical activity in the wrist extensors, biceps brachii, and the upper portion of the trapezius was measured using a portable electromyographer. The recorded data on muscle movements and electrical activity were synchronized. Subjective evaluations of acceptability were evaluated using a visual analog scale. Results and Conclusions: The prototypes with handles at a 30° angle produced the highest acceptability ratings, more neutral wrist positions, lower levels of electromyographic activity for the upper trapezius, and lower elevation angles for the arms. The different measurement methods were complementary in evaluating the upper limbs during handling.Keywords: ergonomic design; usability; electrogoniometry; electromyography; grip perception. HOW TO CITE THIS ARTICLESilva LCCB, Oliveira AB, Silva DC, Paschoarelli LC, Coury HJCG. 30° inclination in handles of plastic boxes can reduce postural and muscular workload during handling. Braz J Phys Ther. 2013 May-June; 17(3):307-318. http://dx

show abstract

“…The muscle parameters, F MAX , tendon slack-length (l SE 0 ), l CE_opt and moment arms of the four lumped muscles were obtained from Nijhof and Kouwenhoven (2000) and Murray et al (1995Murray et al ( , 2000. The contribution of the individual muscle parameters to the parameters of the lumped muscles depended on the relative contribution of the muscle to the total joint moment.…”

Section: Methodsmentioning

confidence: 99%

“…The contribution of the individual muscle parameters to the parameters of the lumped muscles depended on the relative contribution of the muscle to the total joint moment. Moment arms (arm) were related to joint angle on the basis of the relationship between the length of the muscle-tendon complex (l MTC ) and joint angle (Nijhof and Kouwenhoven 2000;Murray et al 1995), measured using the tendon displacement method (Grieve et al 1978). The muscle parameter width (see Appendix) was chosen such that the isometric elbow moment-angle relationship at maximal stimulation was in accordance with that observed experimentally (Singh and Karpovitch 1968;Kullig et al 1984;Van Zuylen et al 1988;An et al 1989;Chang et al 1999).…”

Section: Methodsmentioning

confidence: 99%

A model of open-loop control of equilibrium position and stiffness of the human elbow joint

2006

View full text Add to dashboard Cite

According to the equilibrium point theory, the control of posture and movement involves the setting of equilibrium joint positions (EP) and the independent modulation of stiffness. One model of EP control, the α-model, posits that stable EPs and stiffness are set open-loop, i.e. without the aid of feedback. The purpose of the present study was to explore for the elbow joint the range over which stable EPs can be set open-loop and to investigate the effect of co-contraction on intrinsic low-frequency elbow joint stiffness (K ilf ). For this purpose, a model of the upper and lower arm was constructed, equipped with Hill-type muscles. At a constant neural input, the isometric force of the contractile element of the muscles depended on both the myofilamentary overlap and the effect of sarcomere length on the sensitivity of myofilaments to [Ca 2+ ] (LDCS). The musculoskeletal model, for which the parameters were chosen carefully on the basis of physiological literature, captured the salient isometric properties of the muscles spanning the elbow joint. It was found that stable open-loop EPs could be achieved over the whole range of motion of the elbow joint and that K ilf , which ranged from 18 to 42 N m·rad −1 , could be independently controlled. In the model, LDCS contributed substantially to K ilf (up to 25 N m·rad −1 ) and caused K ilf to peak at a sub-maximal level of co-contraction.

show abstract

Variation of muscle moment arms with elbow and forearm position

Cited by 315 publications

References 15 publications

Efeito da posição da articulação do cotovelo no controle de torque de supinação do antebraço em jovens adultos

Efeito da posição da articulação do cotovelo no controle de torque de supinação do antebraço em jovens adultos

30o inclination in handles of plastic boxes can reduce postural and muscular workload during handling

A model of open-loop control of equilibrium position and stiffness of the human elbow joint

Contact Info

Product

Resources

About