DEAR DR. DONOHUE: I am 92. I have been into physical fitness all my life. I have lost two spouses and have been married to my third wife for 24 years now. I represent the USA in World International Tennis in the 90-and-over category each April. Last year I had to cancel because I cannot walk half a block because of spinal stenosis. What can I take? I hurt most of the time. Please help. I don’t like to sit around all day. – J.D.

ANSWER: Understanding spinal stenosis requires an understanding of how the back is engineered. The spinal cord, an extension of the brain, runs from the back of the head to the lower back. It contains the main body of many nerves and innumerable connecting cables to the brain. It’s only as thick as the little finger. Such a delicate structure requires protection. The backbones protect it. The backbones are constructed with a hollow tunnel, through which the spinal cord runs and by which it is sheltered.

Spinal stenosis is a narrowing of the spinal canal. Often, this narrowing is a consequence of osteoarthritis, the kind of arthritis that comes with aging. The narrowed canal presses on the cord or nerves coming from the cord to produce pain, most often felt in the lower back, the buttock, thigh or calf – or in all of those places. Pain lessens if a person leans slightly forward at the waist when walking. It’s the posture a person assumes when holding onto and pushing a grocery cart. Even when sitting, a person can get pain relief from a slight forward lean.

A physical therapist can teach you how to stretch your back safely and how to strengthen back muscles that can open the narrowed canal. Hot or cold packs – whichever you find works – ease the pain. Tylenol is a reliable and safe pain reliever. Cortisone injections into the back reduce any swelling and can enlarge the spinal canal.

When conservative measures like these fail, then surgically enlarging the canal should be considered. Age has no bearing on the operation if one is in as good a shape as you are.

DEAR DR. DONOHUE: Can one safely venture outdoors in chilly or cold weather after showering, or does one need to wait for a period of time? Back in the old days, our mothers told us that our pores need to close before going out. Most of us never knew if this was true.

Can one sleep every night with a digital alarm clock close to one’s head without risk of brain cancer? One of my doctors said it’s OK, but another recommended against the practice. – R.G.

ANSWER: You can go into the cold shortly after showering. Skin pores don’t stay open very long. I’m not certain what kind of illness comes from open skin pores.

You can sleep with your head on a digital clock or with the clock on your head if you wish. Digital clocks don’t cause brain cancer. If they did, I would be long gone.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com