Tendon excursion and moment arm of index finger muscles

An, Kai Nan; Ueba, Y; Chao, Edward; Cooney, William P.; Linscheid, Ronald L.

doi:10.1016/0021-9290(83)90074-x

Cited by 353 publications

(312 citation statements)

References 9 publications

Supporting

Mentioning

285

Contrasting

Unclassified

Order By: Relevance

“…The joint thickness and posture measurements taken from the video determined the subject-specific tendon moment arms as described by Armstrong and Chaffin (3) and An et al (1). Hand length measurements determine the distances between adjacent joint axes of rotation in the sagittal plane as described by Buchholz and Armstrong (5).…”

Section: Methodsmentioning

confidence: 99%

In vivo finger flexor tendon force while tapping on a keyswitch

Dennerlein

Diao

Mote

et al. 1999

Journal Orthopaedic Research

View full text Add to dashboard Cite

SummaryForce may be a risk factor for musculoskeletal disorders of the upper extremity associated with typing and keying. However, the internal finger flexor tendon forces and their relationship to fingertip forces during rapid tapping on a keyswitch have not yet been measured in vivo. During the open carpal tunnel release surgery of five human subjects, a tendon-force transducer was inserted on the flexor digitorum super-ficialis of the long finger. During surgery, subjects tapped with the long finger on a computer keyswitch, instrumented with a keycap load cell. The average tendon maximum forces during a keystroke ranged from 8.3 to 16.6 N (mean = 12.9 N, SD = 3.3 N) for the subjects, four to seven times larger than the maximum forces observed at the fingertip. Tendon forces estimated from an isometric tendon-force model were only one to two times larger than tip force, significantly less than the observed tendon forces (p = 0.001). The force histories of the tendon during a keystroke were not proportional to fingertip force. First, the tendon-force histories did not contain the highfrequency fingertip force components observed as the tip impacts with the end of key travel. Instead, tendon tension during a keystroke continued to increase throughout the impact. Second, following the maximum keycap force, tendon tension during a keystroke decreased more slowly than fingertip force, remaining elevated approximately twice as long as the fingertip force. The prolonged elevation of tendon forces may be the result of residual eccentric muscle contraction or passive muscle forces, or both, which are additive to increasing extensor activity during the release phase of the keystroke.Although the rate of injury to the tendons at the wrist and adjacent tissues associated with repetitive work is reported to be high (55% of all work-related repetitive motion disorders [6]), the injury mechanisms are not well understood. Along with motion, posture, and vibration, the force exerted during a repetitive task is a risk factor for tendon-related disorders (4,19,23). Understanding how force is transmitted from the site of external application (fingertip) to the internal tissue (finger flexor tendons) is critical to understanding the mechanics of repetitive motion disorders. This understanding determines how the internal biological tissues support an externally applied force, and such knowledge identifies tendons that are exposed to higher forces. The knowledge of in vivo tendon tension also guides techniques of tendon repair, procedures for rehabilitation (15,22), and design of joint replacements (25). Rempel et al. (21) and Martin et al. (18) have measured exposure to force during keyboard work. The fingertip force history during a keystroke contains three distinct phases: (I) the keyswitch compression, (II) the high frequency component during finger impact at the end of keycap motion, and (III) the compression and release of the fingertip (21). Currently, applied fingertip loads and finger postures are used as the input or ind...

show abstract

Section: Methodsmentioning

confidence: 99%

In vivo finger flexor tendon force while tapping on a keyswitch

Dennerlein

Diao

Mote

et al. 1999

Journal Orthopaedic Research

View full text Add to dashboard Cite

show abstract

“…Cooling systems and precise sensors are available. An et al carried out basic studies on cadavers investigating tendon excursion and moment arm of index finger muscles by applying a 5 N weight to the tendons in (An et al 1983). The joints of the index finger were fixated except one, on which the angle was measured using an electric goniometer.…”

Section: Forward Dynamic Modelsmentioning

confidence: 99%

“…According to An et al (1983), a major benefit of hand research is the proper reconstruction of the damaged hand. Valero-Cuevas provides a tool for measuring and quantifying anatomical structures which are crucial for grasp abilities of patients who have to undergo surgery (Valero-Cuevas and Laboratory 2000).…”

Section: The Purpose Of the Modelsmentioning

confidence: 99%

Human hand modelling: kinematics, dynamics, applications

et al. 2012

View full text Add to dashboard Cite

An overview of mathematical modelling of the human hand is given. We consider hand models from a specific background: rather than studying hands for surgical or similar goals, we target at providing a set of tools with which human grasping and manipulation capabilities can be studied, and hand functionality can be described. We do this by investigating the human hand at various levels: (1) at the level of kinematics, focussing on the movement of the bones of the hand, not taking corresponding forces into account; (2) at the musculotendon structure, i.e. by looking at the part of the hand generating the forces and thus inducing the motion; and (3) at the combination of the two, resulting in hand dynam- ics as well as the underlying neurocontrol. Our purpose is to not only provide the reader with an overview of current human hand modelling approaches but also to fill the gaps with recent results and data, thus allowing for an encompassing picture.

show abstract

“…Changes in moment arms of a joint motor tendon reflect alteration in the instantaneous centers of rotation of the tendon during a part or all of the arc of motion [1,2,5,17,18,20]. Although wrist motion is nonlinear and the instantaneous centers vary in different carpal bones, the approximate center of carpal rotation is about the proximal head of the capitate [8,27].…”

Section: Discussionmentioning

confidence: 99%

Wrist kinetics after luno‐triquetral dissociation: the changes in moment arms of the flexor carpi ulnaris tendon

Tang¹,

Xie²,

Yu³

et al. 2002

Journal Orthopaedic Research

View full text Add to dashboard Cite

Wrist biomechanics after luno-triquetral (LT) dissociation is important for understanding the clinical sequelae of the disease and for determining its treatment options. The LT interosseous ligament plays an important role in stabilizing the joint and damage to the ligament would be expected to significantly increase moment arms of tendon of the flexor carpi ulnaris (FCU), the principal ulnar wrist flexor. We investigated the changes in moment arms of FCU tendon after various amounts of sectioning of the ligaments proven to be associated with LT dissociation. In six fresh frozen cadaveric upper extremities, excursions of the FCU tendon were recorded simultaneously with wrist joint angulation during wrist flexion-extension and radioulnar deviation. Tendon excursions were measured in intact wrists, in wrists with sectioning of the dorsal portion of the L T interosseous ligament, in wrists with sectioning of the entire LT interosseous ligament, and finally in wrists with further sectioning of the dorsal radiotriquetral and intercarpal ligaments. Moment arms of the tendon were calculated from tendon excursions and joint motion angulations and expressed as percentage changes from those in the intact wrist. During wrist flexion-extension, moment arms of the FCU tendon after sectioning of the entire LT interosseous ligament and after sectioning of the two capsular ligaments were 112 i 7% and 114 8'%,, respectively; these values were significantly greater than those in the intact wrist. During radioulnar deviation, the moment arms were 114 ?C 11% after sectioning of the dorsal portion of the LT interosseous ligament, 134 * 15'% after sectioning of the entire ligament, and 153 i 18% after sectioning of the capsular ligaments, again being significantly greater than the normal wrist. Increase in moment arms of the FCU tendon after loss of integrity of the L T interosseous ligament and dorsal capsular ligaments may contribute to clinical sequelae of LT dissociation and difficulty in treating this disorder.

show abstract

Tendon excursion and moment arm of index finger muscles

Cited by 353 publications

References 9 publications

In vivo finger flexor tendon force while tapping on a keyswitch

In vivo finger flexor tendon force while tapping on a keyswitch

Human hand modelling: kinematics, dynamics, applications

Wrist kinetics after luno‐triquetral dissociation: the changes in moment arms of the flexor carpi ulnaris tendon

Contact Info

Product

Resources

About