The term neurological injury refers to any kind of disturbance in the functioning
of the nervous system, the most frequent being spinal cord and brain injuries.
Regarding the hand, causes of paralysis can be a result of injuries to the central
nervous system, cerebral palsy, tumours, trauma, etc. Those caused by spinal
cord injury, poliomyelitis, amyotrophic lateral sclerosis, etc., injuries to the brachial
plexus and its peripheral trunks or those produced by ischemic causes.
Various injuries can occur in the hand with different symptoms depending on
which of the radial, median or ulnar nerves are affected, due to their muscle
The result can vary from spastic to flaccid paralysis.
Symptoms vary depending on the affected nerve. In radial nerve palsy, for
example, loss of extension of the metacarpophalangeal and interphalangeal
joints of the thumb can be observed and the inability to extend the wrist is evident.
In the case of median nerve palsy, however, symptoms include loss of abduction
of the thumb, loss of flexion of the metacarpophalangeal joint of the thumb and
loss of the ability to perform thumb opposition, making it impossible to bring the
thumb and index or little finger together. This can be compounded when the
injury affects the forearm and elbow, causing loss of flexion in the interphalangeal
joint of the thumb and distal interphalangeal flexion of the index and middle
In ulnar nerve injuries, symptoms include flattening of the thenar eminence,
partial ulnar claw in the 4th and 5th fingers (if the median and ulnar nerves are
affected, the claw is complete), while the 5th finger is positioned in abduction
and the hand shows hollowing in the interosseous spaces.
As well as rehabilitation techniques applied to each type of neurological injury
of the hand, there is a wide variety of orthosis designs available for each particular
purpose, with objectives that include protecting the skin, preventing deformities,
restoring muscle balance, or as a method of stabilisation, helping functional
rehabilitation, recovering function (if possible) and assisting function as a stabilising
Distinguishing between passive and active according to function, these first ones
have the purpose of keeping the hand, or an anatomical segment of it, in a
particular position, as per the prescriber’s instructions, and can be used during
the day, night or both. Active or functional orthoses allow correction, alignment
or rehabilitation exercises, with selection of the most suitable device depending
on the prescribed function.