This has been available since 1986, who is comparing hemiplegic gaits to these standard references to determine how to correct the hemi gait? Only 10 pages.
http://www.calstatela.edu/faculty/dwon/ee454/Supplementary/WinterYack87.pdf
Summary The EMG patterns for 16 muscles involved in human walking are reported along with stride-to-stride and
inter-subject variability measures. These profiles and measures were developed for basic researchers and clinical investigators as a baseline reference of motor patterns and for use in the diagnosis of gait pathologies.
Evident from a comparison of these patterns were some fundamental aspects of the neuromuscular control and the mechanical
demands of walking. These comparisons can be summarized as follows:
(1) The distal support muscles (soleus, tibialis anterior, gastrocnemii) are the most active muscles, the more proximal muscles are
least active.
(2) The least variable EMG patterns, as quantified by the normalized inter-subject variability measures, are seen in the most distal
single joint muscles, the most variable are the more proximal muscles. The EMGs of the biarticulate muscles, both proximal and
distal, exhibit higher variability than the EMGs of the single joint muscles.
(3) The detailed patterns and levels of EMG activity demonstrate the different mechanical tasks of each muscle over the gait
cycle.
Detailed position of electrodes. You'll have to look at the link.
It is considered useful for basic and clinical
researchers to have a profile of normal EMG
activity that can be used as a reference. Clinical
investigators require these normal patterns in order
to diagnose individual patients (Knutsson and
Richards 1979; Peat et al. 1976; Winter 1984a).
Basic researchers, interested in motor patterns,
require such profiles as a reference for discussions
of the role of various muscles during the gait
cycle, or as inputs for use in simulation models of
human gait. Thus the patterns as presented in
Figs. 3a, b, 4a and b will be useful. A rough
comparison can be made regarding the shapes of
the ensemble averages from other studies. The
only comparison for the erector spinae is with a
single subject (Thorstensson et al. 1982) and the
phasic patterns showing two bursts, one just after
heel contact of the ipsilateral limb and the second,
lesser burst after heel contact of the contralateral
limb. The phasic peaks of EMG activity of the
hamstrings, gastrocnemius, rectus femoris and
tibialis anterior agreed within 5% of the stride
period with inter-subject averages (10 subjects)
reported by Knutsson and Richards (1979). Similar
agreement was seen in the profiles obtained
from 20 subjects (Dubo et al. 1976) for tibialis
anterior, gastrocnemius, medial hamstrings and
vastus lateralis muscles.
From Table III it is valuable to note the
summary of CVs as calculated from these normalized
and unnormalized ensemble averages. The
normalization procedure reduced the variability to
about half (89-48.5%). Again, as was seen from
the range of EMG amplitudes presented in Table
II lower variability is seen in the more distal
muscles, especially the single joint ones: soleus,
tibialis anterior, extensor digitorum longus and
peroneus longus have an average CV (unnormalized)
of 59%. Conversely, the more proximal biarticulate
muscles: sartorius, biceps femoris, semitendinosus,
rectus femoris have an average CV
(unnormalized) of 112% which reinforces their
flexibility and adaptability compared with the
higher and more consistent support and power
Fig. 3. a: inter-subject ensemble average for 8 of the muscles
recorded. EMG profiles from each subject were unnormalized,
with amplitude reported in microvolts. Number of subjects
involved in each ensemble average is indicated along with the
CV. b: inter-subject ensemble average for second group of 8
muscles recorded.
generation roles of the distal single joint muscles.
The normalization technique is such that it
removes any amplitude differences between each
subject's EMG. Thus the resultant CV is a measure
of the dissimilarity in shape of each subject's
EMG over the stride period. If the shapes were
exactly the same for a given muscle, the CV after
normalization would be zero. With these normalized
CVs we again see that the single joint muscles
have the lowest variability and therefore a more
similar pattern. For example, the soleus intra-subject
CV was 31% and inter-subject CV was also
31%; conversely, the medial gastrocs had consistent
patterns within subjects (CV = 33%) but
somewhat dissimilar patterns between subjects
(CV = 61%). Similarly, the more proximal muscles
show greater differences in their inter-subject patterns.
Considerable discussion is possible when we
examine the detailed shape of the individual
muscle profiles as presented in Figs. 3 and 4.
However, general differences and similarities will
be noted. The weight-accepting muscles (tibialis
anterior, extensor digitorum longus, rectus femoris,
vastus lateralis, hamstrings, gluteus maximus and
medius) have their major peak in the first 15% of
stride. Erector spinae also peaks at 10%, to control
forward rotation of the trunk as it decelerates
during weight acceptance; a second peak is seen at
60% presumably for the same purpose when the
contralateral limb is accepting weight. The plantarflexors
(medial and lateral gastrocs, soleus and
peroneus longus) all have peaks at push-off (50%
of stride). Peroneus longus also has an initial peak
at flat foot to control foot inversion. The hip
extensors and knee flexors (gluteus maximus and
hamstrings) have increasing activity in late swing
to arrest the forward movement of the swinging
Fig. 4. a: inter-subject ensemble average for same 8 muscles as
in Fig. 3a except that each subject's mean EMG over the stride
was normalized to 100% prior to averaging. CV was reduced to
about half because the inter-subject amplitude differences have
been eliminated and resultant variability results only from
differences in the shape of the EMG profiles. CV is indicated
along with the mean EMG amplitude (in microvolts) from all
subject profiles that was calculated for this normalization
procedure, b: inter-subject normalized ensemble average for
same 8 muscles as in Fig. 3b.
410 D.A. WINTER, H.J. YACK
lower limb. Tibialis anterior and extensor digitorum
longus have similar patterns during both
stance and swing, the first peak during weight
acceptance (lowering of foot to the ground) and
the second early in swing to dorsiflex the foot for
toe clearance. The two adductors (longus and
magnus) have slightly different patterns. During
stance they both have a moderate but decreasing
activity probably as a co-contraction to stabilize
the hip joint against the action of the hip abductors.
They have major peaks in swing presumably
to control the lateral movement of the swinging
lower limb; adductor longus peaks at 70% stride
and magnus at 80% of stride. The adductor longus
peaks early in swing because of its additional role
of a hip flexor.
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