HEMME APPROACH TO SOFT-TISSUE THERAPY

The same principle applies to the soleus and gastrocnemius. Though
both muscles plantar flex the foot, the soleus is a one-joint muscle and the
gastrocnemius is a two-joint muscle. When the knee is flexed: (1) slack in
the gastrocnemius reduces plantar flexion strength by about 70 percent, and
(2) the soleus can be partially isolated and tested by testing plantar flexion.
● Three points are important for the safety of the patient:
1. Apply resistance slowly (easy on).
2. Do not break the patient's contraction.
3. Remove resistance slowly (easy off).
Resistance should be applied slowly to give the patient enough time to
apply a counterforce. Force applied too quickly may break the patient's
contraction and cause tissue damage. As a rule, the examiner should stop
counterforce when the patient's contraction changes from isometric to
eccentric and the muscle starts to yield. On the opposite side, force removed
too quickly may cause a rebound effect and cause tissue damage.
Isometric resistance is normally applied when a muscle is at or slightly
beyond normal resting length. Because of the arrangement of myofilaments
in the sarcomeres and the viscoelastic properties of a muscle, most muscles
are strongest when the muscle is at or near resting length and weakest when
the muscle is fully stretched or fully shortened. Resting length is normally
about midway between fully contracted and fully stretched. The biceps
brachii approaches resting length when the elbow is flexed to about ninety
degrees.
As a caution, testing a muscle when distal and proximal insertions are
not far enough apart to keep tension on a muscle during contraction may
cause cramping. Any condition that allows actin and myosin myofilaments
to overlap seems to encourage painful spasm. This can be demonstrated by
placing the elbow joint in full flexion (sagittal plane) and then slowly and
carefully contracting the biceps brachii. With only mild contraction, the
biceps will normally start to cramp.
Although high degrees of precision are sometimes required, most
muscles can be tested as a group. According to Beevor's axiom, the body
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HEMME Approach to Soft-Tissue Therapy