ONE OF the great myths of modern manhood is the ragged nobility of the bad back. I always think of JFK, a young man in a rocking chair, flaunting his infirmity in a way you never would with, say, a bladder-control problem. I remember the awe I felt at my own father's suffering, as he lay flat on his back for weeks at a time, bad-tempered and unshaven. If you jumped on the bed you could make him swear. The bad back, I surmised, was the king of all chronic ailments, invisible and yet mighty. I really wanted one.

And so I have one. Like everything else I've inherited from my dad, my version is a bit sub-standard. My father's back used to go out while he was doing things like lifting the washing machine on to breeze-blocks to protect it from rising flood waters. Mine went out last week when I bent over to tie my shoe. If I remember correctly, he finished the job before beginning his heroic convalescence. I left the shoe untied, and crawled to bed.

Perhaps because I have not been seen to have earned it, my back problem commands no respect at home. My wife treats me the way an insurance investigator might treat a fraudulent claimant, setting up little traps to prove I'm fit for work. She leaves the baby on the bed and disappears. He bites my arms and then tries to throw himself on to the floor, and I am forced to hang on to him by one foot while he rails against the indignity of not being allowed to take his own life.

My older son, who is four, regards my immobility as a unique opportunity to engage me in the sort of closed-loop Q & A for which he is renowned. He interrogates me mercilessly on the subject of "How chickens get dead" while placing unrelated objects of interest on my chest.

On my first shuffling trip downstairs, my wife indicates not one but two rubbish bags that need to be taken out. It is clear that she has been saving up rubbish for such an occasion, and she has cannily timed it so that she "just happens" to be seven months pregnant at the time. What choice do I have? I take them out, carefully adjusting the load to suit my twisted frame.

As I wince my way across the gravel path in bare feet, I think of JFK, his boat cut in half by a Japanese destroyer, swimming heroically through the Pacific with a crew member's life-jacket strap between his teeth. Those were the days.

Early in my recovery, I am left alone with the baby when he resolves to end it all on some stairs, and I suffer a relapse while rescuing him against his will. This is regarded as the height of arrogance, and a mandatory school open day is hastily scheduled as punishment. I spend 90 minutes sitting in a miniature chair, looking at a map of a catchment area, and thinking what an excellent Bond villain my wife would make.

All I ever wanted was to suffer in silence, and to stop shaving. Frankly, if I'd known to start with that it would be like this, I would have done all those exercises the doctor gave me.