Dickstein R, Shefi S, Marcovitz E, Villa Y. Anticipatory postural adjustment in selected
trunk muscles in poststroke hemiparetic patients. Arch Phys Med Rehabil 2004;85:261–7.
To study electromyographic characteristics of anticipatory postural adjustment in
axial and lateral, posterior and anterior trunk muscles during the performance of
upper-and lower-limb flexion tasks, in subjects with hemiparesis after stroke and
to determine the relationship between anticipatory activity and subjects’ motor and
A nonrandomized control study.
Geriatric rehabilitation center in Israel.
Fifty poststroke hemiparetic patients and 30 healthy control subjects.
Electromyographic activity of the lumbar erector spinae and of the latissimus dorsi
muscles was recorded bilaterally during flexion of either arm and from the 2 rectus
abdominis and obliquus externus muscles during flexion of either hip.
Main Outcome Measures
Muscles’ onset latency, cross-correlation values between the temporal activation profile
of corresponding pairs and between ipsilateral muscular pairs, symmetry in activation
magnitude of corresponding muscles, and relation between electromyographic activity
and motor and functional performance
Onset latencies of trunk muscles were partially delayed in the patients with longest
hindrance displayed by the erector spinae ipsilateral to the flexing arm (P<.04). Temporal synchronization between pertinent muscular pairs was lower in the
patients than in the healthy subjects, with significant group differences (P<.05 or lower) in the correlations between ipsilateral pairs of trunk muscles. Activation
of the corresponding lateral trunk muscles in the patients was significantly less
symmetrical than in the controls (P<.03 or lower) because of reduced activity on the paretic body side, especially on
flexing of the paretic limbs. Conversely, in the controls as well as on the nonparetic
side of the patients, limb flexion was associated with increased activity in the ipsilateral
lateral trunk muscle. The erector spinae muscle in both groups and on both sides was
more active on the contralateral side than on the ipsilateral side to the flexing
arm. The reduced activity level in trunk muscles on the paretic body side was associated
with deficiencies in motor and functional abilities.
Major impairments in the activity of trunk muscles in hemiparetic subjects were manifested
in the reduced activity level of the lateral trunk muscles, in delayed onset, and
in reduced synchronization between activation of pertinent muscular pairs. These problems
were associated with motor and functional deficits and warrant specific consideration
during physical rehabilitation of poststroke hemiparetic patients.