No announcement yet.

summary of adaptability of motor patterns

This topic is closed.
  • Filter
  • Time
  • Show
Clear All
new posts

  • summary of adaptability of motor patterns

    Dear Biomch-L members:
    Following are all the replies to my original questions concerning
    the adaptability of motor patterns in human locomotion. Thanks to all
    those who replied.

    Wen Liu

    Original questions
    Dear Biomch-L members:
    It have been long observed and documented in certain degree that
    the central neural system have the capability of adapting to compensate
    for the loss of function in the pathological human locomotion. Even
    though these adaptions lead to the abnormal kinematics and kinetics in the
    locomotion, they should not be considered as pathological (D.A. Winter,
    et al., 1990). Following are my questions:

    1) How many such adaptions have been well defined in the human
    walking and running gait?

    2) How many such adaptions have been well defined in the upper
    limbs and whole body related activities?

    3) How can we always be able to distinguish the adaption from the
    pathological change? As we all know, the patients with ankle instability
    tend to move their hip more in order to keep their posture and balance.
    If we observe the excessive motion in their hip joint during balance
    exercise, can we simply ignore the possibility of overuse injury on their
    hip joint soft tissues? This kind of injury may be a secondary injury
    comparing to the primary injury. Is it possible for us to draw a limit
    for the adaption?

    I will post the summary as usual. Thank you in advance.

    Wen Liu
    Institute of Biomedical Engineering
    Drexel University

    Dear Liu,

    You may be interested in the findings of my doctoral research
    evaluating changes in motor control of the trunk muscles in low back
    pain. We evaluated the behaviour of the trunk muscles in response to
    rapid limb movement paradigm. One of the interesting findings from
    the studies of people without low back pain was that transversus
    abdominis was always the first trunk muscle active, preceding the
    onset of EMG of the agonist upper limb muscle. Furthermore, unlike
    the other trunk muscles investigated (RA, EO, IO, ES) the contraction
    of transversus abdominis was not influenced by the direction of
    movement of the limb. By manipulation of the movement preparation we
    were able to demonstarte the organisational strategy used by the CNS
    to control contraction of transversus abdominis was different ot the
    other trunk muscles.

    When we looked at people with a history of recurrent low back pain we
    identified several changes in the motor control of the trunk muscles.
    The most interesting were that TrA was delayed by 50-450 ms, occuring
    after the onset of deltoid. The temporal parameters of the
    contraction of this muscle were now dependent on the direction of
    movement and the control strategy used by the CNS for control of TrA
    was significantly altered.

    In summary the results provide evidence of change in the control of the
    muscles of the trunk associated with pathology. Whether this change
    is an adaptation to low back pain (which is unlikely considering the
    biomechanics and action of this muscle) or perhaps a predisposing
    factor is as yet not confirmed.

    The major low back pain study has been accepted for publication in
    'Spine' and will be out later this year. Please let me know if I can
    help further.

    Paul Hodges

    Paul Hodges
    Department of Physiotherapy Ph: +61 7 3365 4524
    The University of Queensland Fax: +61 7 3365 2775
    St Lucia QLD 4072 Australia Email:

    ************************************************** *****************

    I draw your attention to the following reference:
    Mizrahi, J. Adaptation phenomena and compensatory mechanisms in
    normal and pathological locomotion. In: Sensorimotor Plasticity,
    Theoretical, Experimental and Clinical Aspects, eds. S. Ron, R. Schmid
    and M. Jeannerod, INSERM, Vol 140, Paris, pp 343-366, 1986.

    Prof. Joseph Mizrahi , D.Sc.
    Dept. of Biomedical Eng. Technion, Israel Institute of Technology
    Haifa 32000, Israel
    Phone: +972-4-8294128 Fax: +972-4-8234131

    ************************************************** *****************

    liu wen,
    -one particular set of gait adaptations has been observed in fully
    rehabilitated acl-injured individuals. essentially, the adpatations
    are a reduced mechanical output (torque and power) at the knee and
    increased output at the hip and ankle. these results have been
    observed in walking, running, sideways cutting, and stair climbing.
    not all these adaptations have been observed in each sample of acl-
    injured subjects but they each have been seen in various samples.
    -these results were in agreement with emg analyses which have shown
    reduced quadricep and increased hamstring activations.
    -also, these results were observed in both acl-deficient and acl-
    reconstructed individuals but, possibly, to different extents. some
    deficient subjects have completely eliminated the midstance, knee
    extensor torque, while reconstructed subjects had an extensor torque
    at the knee but much reduced compared to healthy individuals.
    -partial list of refs:
    1. berchuck et al. 1990. j bone & joint surg. 871-877.
    2. devita et al. 1992. med sci sports & exer. 797-806.
    3. lass et al. 1991. acta orthop scand. 9-14.
    4. limbird et al. 1988. j orthop res. 630-638.
    5. timoney et al. 1993. amer j sports med. 887-889.
    paul devita
    biomechanics lab
    east carolina university

    ************************************************** ********

    Dear Wen Liu,

    I am interested in walking strategies as a result of constraints at the foot
    and ankle. In response to your first question, the following are a number
    of references which implicitly or explicitly describe walking strategies in
    various patient populations;

    Mueller MJ, Minor SD, Sahrmann SA, Schaaf JA, Strube MJ.
    Differences in the gait characteristics of patients with
    diabetes and peripheral neuropathy compared with age-matched
    controls. Phys Ther 1994;74:299-308.

    Winter DA, Patla AE, Frank JS, Walt SE: Biomechanical
    walking pattern changes in the fit and healthy elderly. Phys
    Ther 1990;70:340-347.

    Winter DA, Sienko SE: Biomechanics of below-knee amputee
    gait. J Biomechanics 1988;21:361-367.

    Olney SJ, MacPhail HE. Hedden DM, Boyce WF: Work and power
    in hemiplegic cerebral palsy gait. Phys Ther. 1990;70:431-

    Mueller MJ, Sinacore DR, Hoogstrate S, Daly L: Effect of
    hip and ankle walking strategies on peak plantar pressures:
    Implicaitons for neuropathic ulceration. Arch Phys Med Rehab

    Michael J. Mueller, PhD, PT
    Program in Physical Therapy
    Washington University School of Medicine
    4444 Forest Park Blvd
    Box 8502
    St. Louis, MO 63108
    Phone: 314/ 286-1400
    FAX: 314/ 286-1410