I have suffered from dizziness for months. It started years ago but my dizziness has never lasted for such a long period. My life is in limbo as I’m fearful of going anywhere.

Irene Smith, Dundee.

A common procedure is the Epley manoeuvre, which takes minutes. It’s carried out by trained medic and involves moving the patient’s head through a series of rotations and positions 

Dr Martin Scurr replies: I’m sorry to hear this is having such an effect on your life. Benign paroxysmal positional vertigo (BPPV), which you say you were diagnosed with years ago, is a common cause of dizziness (‘vertigo’ is the medical name). It’s caused by a problem in the inner ear system that controls balance, and the dizziness is triggered by movement, usually of the head.

BPPV occurs when calcium crystals that are found naturally there become dislodged and end up in the wrong part of the inner ear, causing disruption to signals to the brain.

Why this happens is not clear, but the crystals move into one of the canals that make up the inner-ear balance structure.

You ask if the BPPV could be linked to ankylosing spondylitis, which you also say you suffer from. There is no causal link, but it could be implicated. Let me explain: ankylosing spondylitis is a type of arthritis, caused by inflammation, mainly affecting the spine.

In advanced cases it can affect the vertebrae immediately below the skull and this, in turn, might compress the spinal cord, causing balance difficulty or vertigo. It’s possible this could be confused with BPPV.

Or it may be that the inflammatory process of the condition – again affecting the top of the spine – has restricted blood flow in the arteries in that area.

A third possibility is that non-steroid, anti-inflammatory medication, used to treat the pain and stiffness in your neck and spine, can potentially cause side-effects such as dizziness.

If it is BPPV, the commonly used procedure to treat it is the Epley manoeuvre, which takes minutes. It’s carried out by trained medic and involves moving the patient’s head through a series of rotations and positions, both seated and lying down. It is almost always effective.

A study of 1,000 patients showed that one session is effective in 85 per cent of patients.

However, it may be that patients with neck problems associated with ankylosing spondylitis are not able to undergo the movements of the head required when the Epley manoeuvre is carried out.

If that’s the case with you, I’d suggest asking for a referral to a neurotologist – a specialist in balance, ear and problems relating to the base of the skull.

I’m still working as a builder at 76, but my knees are giving me trouble.

I have read that cartilage replacement – rather than joint replacement – is very successful and less invasive.

Is it available on the NHS?

SGN Norris, South London.

Dr Scurr replies: The standard NHS treatment for osteoarthritis of the knee is a partial or total knee replacement. What you are describing is a different procedure where only the worn cartilage is repaired or replaced. The techniques used for this are still largely experimental. One method is to drill tiny holes into the bone under the area of damage – the idea is to trigger new cartilage-like tissue to grow, by stimulating the underlying bone marrow.

Another technique is to harvest the patient’s cartilage cells and culture these in the laboratory and then re-implant them.

Alternatively, plugs of bone and cartilage can be moved from areas that are less weight-bearing to where the load is heaviest.

But these complicated procedures are only suitable for small areas of damage. (I’d avoid going private for stem-cell therapies – touted as being able to regenerate worn cartilage – as these are expensive and unproven.)

If you have advanced arthritis, the future lies with joint replacement – and with surgery there is no reason why your working life should not continue.

■ Write to Dr Scurr at Good Health, Daily Mail, 9 Derry Street, London, W8 5HY or email drmartin@dailymail. co.uk. Replies should be taken in a general context and always consult your own GP with any health concerns.