Healthcare and Medicine Reference
In-Depth Information
medial hamstrings, the semimembranosus and semiten-
dinosus, are complemented by the single lateral ham-
string, the biceps femoris (although the outer leg is also
supported by two 'hamstrings' - see Ch. 6, p. 139). All
three of the hamstrings are 'expresses', affecting both
knee and hip.
Separating the hamstrings
Much has been written about the hamstrings, but very
little about the separate functions of the hamstrings. The
medial hamstrings (semitendinosus and semimembra-
nosus) create medial tibial rotation when the knee is
flexed. The lateral hamstring (biceps femoris) creates
lateral rotation of the lower leg on the femur in the same
situation. To perform these separate functions, the two
sets of muscles must be able to work separately. This
differential movement between inner and outer ham-
strings is especially important in sports or activities
where the hips move side-to-side while there is pressure
on the knee, as in jazz dance, skiing, football, or rugby.
In running - pure flexion and extension - this separation
is not required as the inner and outer hamstrings always
work in tandem.
To feel how far the inner and outer hamstring func-
tion is separated, have your client lie prone, preferably
with the knee flexed for easier access, and begin to feel
your way up the space between the two sets of ham-
strings, just above the endangerment area in the popli-
teal space (Figs 3.18 and 3.21). Here it will be easy to feel
the separation, for they are quite tendinous, and at least
an inch or two (3-5 cm) apart. Now move up toward the
ischial tuberosity, being careful to stay in the 'valley'
between the two sets of muscles. How far up can you
feel a palpable valley? For some people, the entire group
of three muscles will be bound together a few inches up
from the popliteal space; for others a division will be
palpable halfway or more to the ischial tuberosity. In
dissection the potential separation can go up to within
a few inches, or 10 cm, of the ischial tuberosity.
To test this functionally, have your client bend the
knee you are assessing to a right angle, and then twist
that foot medially and laterally, while you rest a hand
across the muscles and palpate to feel if they are working
separately.
To treat bound hamstrings, insert (or wiggle or
'swim') your fingers in between the muscles at the
lowest level of binding as your client continues to slowly
rotate the lower leg medially and laterally with the knee
bent. The binding fascia will gradually release, allowing
your fingers to sink toward the femur. Continue working
upward a few inches at a time until you reach the limit
of that technique (DVD ref: Superficial Back Line,
31:08-33:57).
Fig. 3.21 A superficial view (left) shows the hamstrings
disappearing under the gluteus maximus, but despite the gluteus
being a superficial muscle on the back, it is not part of the SBL. It
is disqualified by involving both a change in direction, and a
change of level. Remove the gluteus (which will show up later as
part of other lines) to see the clear connection from the hamstrings
to the sacrotuberous ligament.
and strains coming up from the foot, can contribute to
this pattern, working differentially on the two sets of
hamstrings can be very helpful in releasing the leg back
into alignment.
If the tibia is medially rotated (as measured by the
direction in which the tibial tuberosity faces relative to
the patella - the outside edges of the patella and tibial
tuberosity should form an isoceles triangle), then manual
or stretching work on the medial set of hamstrings (sem-
itendinosus and semimembranosus) is required. If the
tibia is turned laterally, work on the biceps femoris (both
heads) is necessary. The tissues should be worked
toward the knee. Begin with whatever general stretch-
ing or work with the hamstrings you had planned, then
do additional work on the relevant hamstring to reduce
the rotation, using the client's slow eccentric lengthen-
ing of the tissues occasioned by bringing the knee
from flexion to extension. The tissues that maintain
these rotations are located deep within the hamstring
Rotation at the knee
Although functional rotation of the knee is only possible
when the knee is flexed, postural rotation of the tibia on
the femur, medial or lateral, is quite common. Although
several factors, including strain in peri-articular tissues
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