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Spinal anaesthesia — the injection in the back
This causes more fear than almost anything else we discuss — and the fears are specific, widely repeated, and worth answering one by one rather than waving away.
What people worry about
The needle will touch my spinal cord and I will be paralysed.
The needle goes in below where the spinal cord ends.
The spinal cord finishes higher up in the back. Below that point there are only loose nerve roots floating in fluid, which move out of the way of a fine needle rather than being pierced by it.
The anaesthetist deliberately chooses that level for exactly this reason. Permanent nerve damage from spinal anaesthesia is extremely rare.
I will get back pain for the rest of my life.
This is the most widespread belief about spinal anaesthesia, and the evidence does not support it.
Soreness at the injection site for a day or two is common — it is a small needle through skin and muscle, and it feels like a bruise.
Long-term back pain is not caused by spinal anaesthesia. Studies comparing people who had spinal anaesthesia with those who had general anaesthesia find the same rates of back pain later. People who have surgery often have back pain afterwards — but the operation, the positioning and the time in bed explain it, not the injection.
I will be awake and I will feel them operating.
You will be awake. You will not feel pain.
You feel pressure, movement and pulling — but not pain. Many people describe it as someone working on a leg that does not belong to them.
And you do not have to be alert. If you would rather not be aware of the room, the anaesthetist can give sedation so you are drowsy or asleep throughout. Ask for it. It is a normal request and nobody will think anything of it.
My legs will be weak afterwards, or I will not be able to walk properly.
The numbness wears off completely, usually within two to four hours.
Your legs feel heavy and useless at first and the sensation returns gradually, often with pins and needles. This is expected.
You will be helped up for the first time only when the anaesthetist is satisfied the block has fully worn off — which is why nurses ask you to move your toes.
General anaesthesia would be safer. At least I would not know anything.
For many orthopaedic operations, spinal anaesthesia is the safer option.
Less nausea and vomiting afterwards, better pain control in the first hours, less blood loss for some operations, no breathing tube, and a lower risk of confusion afterwards in older patients — which matters a great deal after a hip fracture.
Your anaesthetist will explain which is right for you. It is their decision to advise and yours to consent to.
What actually happens
You sit on the edge of the trolley or lie on your side 2 minutes
You will be asked to curl forward and round your back like a prawn. A nurse supports you. Holding still is the only thing you have to do.
The back is cleaned 1 minute
Cold antiseptic. This is thorough because sterility matters here.
Local anaesthetic in the skin A few seconds
A brief sting, then that area goes numb.
The spinal injection 30–60 seconds
Pressure, and sometimes a brief tingle down one leg — tell the anaesthetist if that happens; it is usually harmless and they will adjust. Most people say it is much less than they had braced for.
You lie down and it begins to work 5–10 minutes
A warm, tingling, heavy feeling that spreads down from the waist. The anaesthetist checks the level with cold spray before anything starts.
Surgery As long as it takes
You feel pressure and movement, no pain. You can talk, or have sedation and sleep.
It wears off 2–4 hours
Sensation returns gradually. Tell the nurses when you can wiggle your toes.
Guides for you
In your language, free to download. Each one is a short PDF you can keep on your phone or print.
Ready when you are.
Call either clinic during consulting hours, or send a WhatsApp message any time.