Dc. Kerrigan et al., BIOMECHANICAL GAIT ALTERATIONS INDEPENDENT OF SPEED IN THE HEALTHY ELDERLY - EVIDENCE FOR SPECIFIC LIMITING IMPAIRMENTS, Archives of physical medicine and rehabilitation, 79(3), 1998, pp. 317-322
Objectives: It is not known whether changes in the biomechanics of eld
erly gait are related to aging per se, or to reduced walking speed in
this population, The goals of the present study were to identify speci
fic biomechanical changes, independent of speed, that might impair gai
t performance in healthy older people by identifying age-associated ch
anges in the biomechanics of gait, and to determine which of these cha
nges persist at increased walking speed. Design: Stereophotogrammetric
and force platform data were collected, Differences in peak joint mot
ion (kinematic) and joint moment and power (kinetic) values between he
althy young and elderly subjects at comfortable and increased walking
speed were measured. Setting: A gait laboratory. Subjects: Thirty-one
healthy elderly (age 65 to 84 years) and 31 healthy young adult subjec
ts (age 18 to 36 years), all without known neurologic, musculoskeletal
, cardiac, or pulmonary problems. Main Outcome Measures: All major pea
k kinematic and kinetic variables during the gait cycle, Results: Seve
ral kinematic and kinetic differences between young and elderly adults
were found that did not persist when walking speed was increased, Dif
ferences that persisted at both comfortable and fast walking speeds we
re reduced peak hip extension, increased anterior pelvic tilt, and red
uced ankle plantarflexion and ankle power generation, Conclusion: Gait
performance in the elderly may be limited by both subtle hip flexion
contracture and ankle plantarflexor concentric weakness. Results of th
e current study should motivate future experimental trials of specific
hip flexor stretching and ankle plantarflexor concentric strengthenin
g exercises to preserve and potentially improve walking performance in
the elderly. (C) 1998 by the American Congress of Rehabilitation Medi
cine and the American Academy of Physical Medicine and Rehabilitation.