CARLTON drafted Matthew Kreuzer knowing the No. 1 draft pick would probably need hip surgery in the first two years of his career and is at risk of developing an arthritic hip.

Kreuzer is not injured, but has a condition called femoroacetabular impingement (FAI), which means he has a small, bony bump growing on his right hip. Experts believe that FAI will become a common condition — or "the next osteitis pubis" — in AFL circles.

The bump — known as a Ganz lesion — may sit there for several years and not do anything, and can be removed with a simple arthroscopy, but once it starts to grind into the cartilage lining of a hip, it will cause irreversible damage, arthritis and shorten a footballer's career.

The condition, which affects mostly active people, is thought to be a leading cause of many cases of osteitis pubis, adductor pain and chronic hip problems. It is believed to affect up to four or five players at any club.

The Blues — like Kreuzer and the other 15 teams — discovered he had the condition ahead of the AFL draft camp last October, when each prospective draftee underwent a thorough medical screening. It meant that rather than have the young ruckman break down unexpectedly in the next couple of years, the club understood his condition and could make decisions on how to manage it.

Carlton football manager Steven Icke said the club followed specialist advice suggesting Kreuzer be allowed to train and play until symptoms presented, after involving the club's own doctor, and stressed the condition was separate to the knock to the hip that kept Kreuzer out of Thursday night's season opener against Richmond.

He said the club never considered sending the teenager for pre-emptive surgery, which was risky, but would keep a close eye on him and act only when he presented symptoms.

"We were obviously comfortable drafting Matthew, because we did draft him, and you do the same with any player. Once you know there's something to watch, you watch it," he said.

"You don't want to jump at shadows, but it's the same as Joel Selwood and his knee injury a couple of years ago. If you understand exactly what you're getting with a player then you can plan for it and manage it. It's better to know than not to know."

The 70-odd players invited to the draft camp each year undergo full cardiovascular and muscular skeletal exams and are sent by the AFL to see specialists if required.

The league has recently commissioned research into the prevalence and impact of FAI injuries.