Hand digit control in children: age-related changes in hand digit force interactions during maximum flexion and extension force production tasks

We studied the finger interactions during maximum voluntary force (MVF) production in flexion and extension in children and adults. The goal of this study was to investigate the age-related changes and flexion–extension differences of MVF and finger interaction indices, such as finger inter-dependency (force enslaving (FE): unintended finger forces produced by non-instructed fingers during force production of an instructed finger), force sharing (FS; percent contributions of individual finger forces to the total force at four-finger MVF), and force deficit (FD; force difference between single-finger MVF and the force of the same finger at four-finger MVF). Twenty-five right-handed children of 6–10 years of age and 25 adults of 20–24 years of age participated as subjects in this study (five subjects at each age). During the experiments, the subjects had their forearms secured in armrests. The subjects inserted the distal phalanges of the right hand into C-shaped aluminum thimbles affixed to small force sensors with 20° of flexion about the metacarpophalangeal (MCP) joint. The subjects were instructed to produce their maximum isometric force with a single finger or all four fingers in flexion or extension. In order to examine the effects of muscle–force relationship on MVF and other digit interaction indices, six subjects were randomly selected from the group of 25 adult subjects and asked to perform the same experimental protocol described above. However, the MCP joint was at 80° of flexion. The results from the 20° of MCP joint flexion showed that (1) MVF increased and finger inter-dependency decreased with children’s age, (2) the increasing and decreasing absolute slopes (N/year) from regression analysis were steeper in flexion than extension while the relative slopes (%/year) with respect to adults’ maximum finger forces were higher in extension than flexion, (3) the larger MVF, FE, and FD were found in flexion than in extension, (4) the finger FS was very similar in children and adults, (5) the FS pattern of individual fingers was different for flexion and extension, and (6) the differences between flexion and extension found at 20° MCP joint conditions were also valid at 80° MCP joint conditions. We conclude that (a) the finger strength and independency increase from 6 to 10 years of age, and the increasing trends are more evident in flexion than in extension as indexed by the absolute slopes, (b) the finger strength and finger independency is greater in flexion than in extension, and (c) the sharing pattern in children appears to develop before 6 years of age or it is an inherent property of the hand neuromusculoskletal system. One noteworthy observation, which requires further investigation, was that FE was slightly smaller in the 80° condition than in the 20° condition for flexion, but larger for extension for all subjects. This may be interpreted as a greater FE when flexor or extensor muscles are stretched.

[1]  S C Gandevia,et al.  Distribution of the forces produced by motor unit activity in the human flexor digitorum profundus , 2002, The Journal of physiology.

[2]  K Hirunagi,et al.  Immunocytochemical demonstration of serotonin-immunoreactive cerebrospinal fluid-contacting neurons in the paraventricular organ of pigeons and domestic chickens. , 1992, Progress in brain research.

[3]  Jae Kun Shim,et al.  Is there a timing synergy during multi-finger production of quick force pulses? , 2004, Experimental brain research.

[4]  N. A. Bernshteĭn.  The co-ordination and regulation of movements , 1967 .

[5]  K. Kursa,et al.  In vivo flexor tendon forces increase with finger and wrist flexion during active finger flexion and extension , 2006, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[6]  V. T. Inman,et al.  Mechanics of human isolated voluntary muscle. , 1947, The American journal of physiology.

[7]  K. Newell,et al.  Age differences in noise and variability of isometric force production. , 2001, Journal of experimental child psychology.

[8]  M. Hackel,et al.  Changes in hand function in the aging adult as determined by the Jebsen Test of Hand Function. , 1992, Physical therapy.

[9]  J. F. Soechting,et al.  Synergistic finger movements in a skilled motor task , 2004, Experimental Brain Research.

[10]  David A. Winter,et al.  Biomechanics and Motor Control of Human Movement , 1990 .

[11]  Minoru Shinohara,et al.  Effects of age and gender on finger coordination in MVC and submaximal force-matching tasks. , 2003, Journal of applied physiology.

[12]  K. Reilly,et al.  Independence of force production by digits of the human hand , 2000, Neuroscience Letters.

[13]  M. Sjöström,et al.  Growth and development of human muscle: A quantitative morphological study of whole vastus lateralis from childhood to adult age , 1992, Muscle & nerve.

[14]  M. Latash,et al.  Prehension synergies: trial-to-trial variability and hierarchical organization of stable performance , 2003, Experimental Brain Research.

[15]  Y. Shinoda,et al.  Spinal branching of pyramidal tract neurons in the monkey , 1979, Experimental Brain Research.

[16]  R. Geuze,et al.  Children who are clumsy, five years later , 1993 .

[17]  Zong-Ming Li.  The influence of wrist position on individual finger forces during forceful grip. , 2002, The Journal of hand surgery.

[18]  J Duysens,et al.  Development of isometric force and force control in children. , 2003, Brain research. Cognitive brain research.

[19]  M J Botte,et al.  Anatomy of the juncturae tendinum of the hand. , 1990, The Journal of hand surgery.

[20]  J. Stephens,et al.  Cross‐correlation analysis of motor unit activity recorded from two separate thumb muscles during development in man. , 1997, The Journal of physiology.

[21]  J F Soechting,et al.  Kinematics of typing: parallel control of the two hands. , 1992, Journal of neurophysiology.

[22]  M. Latash.  There is no motor redundancy in human movements. There is motor abundance. , 2000, Motor control.

[23]  Marc H Schieber,et al.  Human finger independence: limitations due to passive mechanical coupling versus active neuromuscular control. , 2004, Journal of neurophysiology.

[24]  E. Fetz,et al.  Postspike facilitation of forelimb muscle activity by primate corticomotoneuronal cells. , 1980, Journal of neurophysiology.

[25]  Jae Kun Shim,et al.  Prehension synergies in three dimensions. , 2005, Journal of neurophysiology.

[26]  Gregor Schöner,et al.  A mode hypothesis for finger interaction during multi-finger force-production tasks , 2003, Biological Cybernetics.

[27]  M. Botte,et al.  Anatomy and functional significance of the long extensors to the fingers and thumb. , 2001, Clinical orthopaedics and related research.

[28]  R. Lemon,et al.  Selective facilitation of different hand muscles by single corticospinal neurones in the conscious monkey. , 1986, The Journal of physiology.

[29]  N. A. Bemstein.  The problem of interrelation between coordination and localization , 1935 .

[30]  D. Downham,et al.  Differences in fiber number and fiber type proportion within fascicles. A quantitative morphological study of whole vastus lateralis muscle from childhood to old age , 1992, The Anatomical record.

[31]  Vladimir M. Zatsiorsky,et al.  Finger interaction during accurate multi-finger force production tasks in young and elderly persons , 2004, Experimental Brain Research.

[32]  J. F. Soechting,et al.  Anticipatory and sequential motor control in piano playing , 1997, Experimental Brain Research.

[33]  P. Sacco,et al.  A cross-sectional survey of upper and lower limb strength in boys and girls during childhood and adolescence. , 1990, Annals of human biology.

[34]  Michael H. Kutner.  Applied Linear Statistical Models , 1974 .

[35]  M H Schieber,et al.  Partial Inactivation of the Primary Motor Cortex Hand Area: Effects on Individuated Finger Movements , 1998, The Journal of Neuroscience.

[36]  Teresa L Brininger,et al.  Motion enslaving among multiple fingers of the human hand. , 2004, Motor control.

[37]  Minoru Shinohara,et al.  Age effects on force produced by intrinsic and extrinsic hand muscles and finger interaction during MVC tasks. , 2003, Journal of applied physiology.

[38]  M. Latash,et al.  Learning multi-finger synergies: an uncontrolled manifold analysis , 2004, Experimental Brain Research.

[39]  V. Hömberg,et al.  Maturation of fastest afferent and efferent central and peripheral pathways: No evidence for a constancy of central conduction delays , 1994, Neuroscience Letters.

[40]  Halla B. Olafsdottir,et al.  The emergence and disappearance of multi-digit synergies during force-production tasks , 2005, Experimental Brain Research.

[41]  Marc H Schieber,et al.  Hand function: peripheral and central constraints on performance. , 2004, Journal of applied physiology.

[42]  F. Danion,et al.  The effect of a fatiguing exercise by the index finger on single- and multi-finger force production tasks , 2001, Experimental Brain Research.

[43]  K. Newell,et al.  Children's coordination of force output in a pinch grip task. , 2002, Developmental psychobiology.

[44]  Isometric force regulation in children , 1995 .

[45]  V. Hömberg,et al.  Development of speed of repetitive movements in children is determined by structural changes in corticospinal efferents , 1992, Neuroscience Letters.

[46]  J. Piek,et al.  The identification of children with developmental coordination disorder by class and physical education teachers. , 1997, The British journal of educational psychology.

[47]  B. Smits-Engelsman,et al.  Fine motor deficiencies in children diagnosed as DCD based on poor grapho-motor ability. , 2001, Human movement science.

[48]  Karl M Newell,et al.  Deterministic and stochastic processes in children's isometric force variability. , 2003, Developmental psychobiology.

[49]  T. Gaussen,et al.  A 2-year follow-up study of children with motor coordination problems identified at school entry age. , 1987, Child: care, health and development.

[50]  M. Latash,et al.  Force sharing among fingers as a model of the redundancy problem , 1998, Experimental Brain Research.

[51]  M. Latash,et al.  Enslaving effects in multi-finger force production , 2000, Experimental Brain Research.

[52]  M. Latash,et al.  Age-related changes in finger coordination in static prehension tasks. , 2004, Journal of applied physiology.

[53]  M. Latash,et al.  Prehension synergies: Effects of object geometry and prescribed torques , 2002, Experimental Brain Research.

[54]  M. Smyth,et al.  Clumsiness in Adolescence: Educational, Motor, and Social Outcomes of Motor Delay Detected at 5 Years , 1994 .

[55]  M H Schieber,et al.  Quantifying the Independence of Human Finger Movements: Comparisons of Digits, Hands, and Movement Frequencies , 2000, The Journal of Neuroscience.

[56]  Raymond D. Kent,et al.  Power and precision grip force control in three-to-five-year-old children: velocity control precedes amplitude control in development , 2006, Experimental Brain Research.

[57]  P M Rossini,et al.  Latency jump of "relaxed" versus "contracted" motor evoked potentials as a marker of cortico-spinal maturation. , 1993, Electroencephalography and clinical neurophysiology.