Spastic Hand

Spasticity can follow damage to the brain. It may start at or soon after birth, as in cerebral palsy, or later in life after a head injury or a stroke. The muscles themselves are healthy, but the brain no longer controls them properly, so a particular group of muscles stays tight and overpowers the opposing group.

This is different from a floppy, paralysed hand, where muscles have lost their nerve supply. In a spastic hand the problem is too much pull in the wrong direction.

In a very typical case, the affected arm is held like this:

• The elbow is slightly bent.
• The arm is turned inward (internally rotated).
• The wrist is bent down (flexed).
• The fingers are curled into a fist, with the thumb tucked into the palm.
• Part of the thumb bends backwards, at the knuckle where it joins the hand (hyperextension of the metacarpophalangeal, or MP, joint).

Over time this posture can make the palm hard to clean, the skin can break down, and dressing and daily care become difficult.

The thumb is often the most troublesome part. In a thumb-in-palm deformity, the thumb is pulled across the palm and its MP joint bends backwards, so the hand cannot open to hold anything. Treatment options include:

• Releasing the adductor pollicis in the palm: loosening the tight muscle that pulls the thumb into the palm.
• Rerouting the abductor pollicis longus (APL) around the brachioradialis (BR): a tendon is looped so that it pulls the thumb out of the palm.
• Stabilising the MP joint (sesamoid-metacarpal fusion): a small fusion that stops the thumb knuckle bending backwards.

Not every spastic hand needs surgery. Before planning anything, the hand is examined for:

• how much voluntary control the patient has over the fingers and wrist,
• whether the hand can feel (sensation),
• whether the joints are still supple or have become stiff,
• the patient's age, general health and, for children, ability to take part in therapy,
• the goal: better use of the hand, easier care and hygiene, or improved appearance.

Surgery is usually considered when the condition is stable and therapy and splinting alone have not achieved the goal. Setting realistic expectations is part of every consultation.

Many patients start with, or continue alongside surgery with:

• Therapy to stretch tight muscles and train useful movement.
• Splints to hold the wrist, fingers and thumb in a better position. Splints are designed and made in-house at the clinic.
• Botulinum toxin injections, which temporarily relax selected tight muscles.

For a detailed look at choices for children with cerebral palsy and adults after a stroke, read the spastic hand guide.

Surgery rebalances the hand by loosening muscles that pull too hard and redirecting tendons to support weak movements. Common procedures include:

1. Tendon transfer from FCU to ECRB to correct a bent wrist: the flexor carpi ulnaris, which bends the wrist down, is rerouted to the extensor carpi radialis brevis so that it helps lift the wrist instead.
2. Release of the flexor-pronator muscles (Zancolli aponeurotic release) to correct tight flexion.
3. Rerouting the pronator muscle to correct a forearm that is permanently turned palm-down (pronated).

After surgery, a period of splinting and therapy is essential to keep the gains.

Book a consultation to discuss whether surgery could help.