Hereditary spastic paraplegia

Also called HSP, Familial spastic paraparesis

Inherited progressive stiffness and weakness of the legs. Slow, usually not life-shortening, and frequently mistaken for MS or cerebral palsy.

What it is

A group of inherited conditions causing progressive stiffness and weakness of the legs, from degeneration of the longest nerve fibres running down the spinal cord.

There are many genetic types. Pure HSP affects the legs and bladder only; complex forms add other features such as cognitive difficulty, neuropathy or ataxia.

It progresses slowly, usually over decades, and in the pure form does not shorten life. Many people continue walking with aids for many years.

It is commonly misdiagnosed. In children it is mistaken for cerebral palsy, and the giveaway is that HSP progresses while cerebral palsy is static. In adults it is mistaken for multiple sclerosis, and the giveaway is the absence of relapses and of the typical MRI changes, together with a family history.

Getting the diagnosis right matters for genetic counselling, for family members, and for avoiding unnecessary treatment.

There is no disease-modifying treatment. Everything worthwhile is symptomatic: managing spasticity, physiotherapy, orthotics, bladder management and pain control, done well and consistently. See contractures and spasticity.

Signs you might notice

Gradually increasing stiffness of the legs, often noticed as tripping, catching the toes, or shoes wearing unevenly.

A stiff, scissoring gait.

Weakness, particularly of the muscles lifting the foot and the hip.

Muscle spasms and cramps.

Urinary urgency and frequency, which is common and often the most troublesome symptom.

High arched feet.

In complex forms: peripheral neuropathy, ataxia, learning difficulty, or epilepsy.

Prompting a rethink: a child diagnosed with cerebral palsy whose walking is deteriorating rather than static; an adult diagnosed with MS who has no relapses, a normal MRI and a family history of similar problems.

Urgent: sudden deterioration, which is not typical and suggests something else, including a treatable cause.

How it can affect day-to-day life

Because progression is slow, people adapt without noticing, and function is often lost before any help is asked for. Regular review rather than crisis response works far better.

Ankle-foot orthoses transform walking for many people and are frequently offered too late or fitted badly.

Spasticity management, with stretching, physiotherapy, baclofen and sometimes botulinum toxin, needs to be ongoing rather than a one-off.

Bladder urgency is often the symptom that limits life most and is treatable; it is under-reported because people do not connect it to a leg condition.

Fatigue from the effort of walking is substantial and under-recognised.

Genetic counselling matters for family planning, and the inheritance pattern varies by type, so the specific genetic diagnosis is useful.

Falls prevention becomes central as the condition progresses. See falls.

Supporting someone well

Ask for a genetic diagnosis; it clarifies inheritance and the likely course.

Question a cerebral palsy diagnosis in a child whose walking is getting worse rather than staying stable.

Question an MS diagnosis in an adult with no relapses, a normal MRI and a family history.

Ask for physiotherapy and a daily stretching programme, and keep it going.

Ask for orthotics assessment early, and persist if the first pair does not work.

Raise bladder urgency; it is treatable and it is often not mentioned.

Ask about spasticity treatment including baclofen and botulinum toxin.

Ask for occupational therapy and falls assessment before there is a crisis.

Ask for genetic counselling for the family.

Where to get help

A GP practice for referral to neurology, ideally a specialist neuromuscular or ataxia service.

Physiotherapy, orthotics and continence services for ongoing management.

Ataxia UK and the Brain and Spine Foundation both support people with rare progressive neurological conditions.