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causes facilitation (Bahnung) of their stretch reflex, and at the same time the constant
over-stretching of their antagonists, the extensors of hips and knees, result in a weakening
of the stretch reflex of the latter. Conversely, in paraplegics with complete lesions who
did not develop flexion contractures of legs and hips during the early stages through
faulty positioning but remained free from septic conditions, the initially pre-dominant
flexor reflex synergy gradually decreased in later stages and the extensor reflex synergy
became predominant. Factors which have proved effectual in facilitating extensor
activity are:
1
Placing the paralysed limbs during spinal shock in abduction and extension at hips
and knees and keeping feet and toes in dorsi-flexion while the patient lies in supine
position.
2 Placing the patient in prone position, which, particularly in high thoracic and cervical
lesions, as in babies whose pyramidal tracts are not yet developed, promotes the extension
reflex of the body.
3 Early passive movements of the paralysed limbs.
4 Restoration of the upright position of paraplegics and tetraplegics—in particular
standing in parallel bars.
It has already been pointed out that prolonged overstretching of the skeletal muscles
by faulty positioning of the paralysed limb causing structural damage of the muscle and
resulting in unrestrained action of its antagonist represents an important factor in deter
mining the reflex pattern of the paralysed limb. Another common cause of structural
damage of a muscle and its peripheral nerve supply is pressure produced by plaster or
splint. In this connection, the constant pressure against the capitulum fibulae, causing
damage to the popliteal nerve and thus resulting in additional peripheral nerve lesion of
the tibialis anterior and the dorsi-flexors of the toes, is one of the frequent causes of the
predominance of the plantar flexors of the toes and feet.
