THE AFL has begun research into shoulder problems after they were highlighted as an area of concern in the League's injury survey, which was released on Wednesday.

The number and severity of shoulder injuries has been steadily trending upwards during much of the past decade.

In 2001 there were 1.1 new shoulder sprains and dislocations per club per season.

But by last year this figure had climbed to 1.6.

Much of the increase been linked to the increasing number of tackles laid in games.

Back in 1988, for instance, Hawthorn's Robert DiPierdomenico was the VFL's leading tackler with an average of 3.1 per game.

Last year, North Melbourne's Andrew Swallow topped the tackling table with an average of 8.3 per game.

"There's a current research project on looking at shoulder injuries in relation to tackling trends," Dr Hugh Seward, the head of the AFL Medical Officers' Association, said on Wednesday.

Current statistics show that players involved in a tackle are at risk, but it's usually the person being tackled who gets injured.

However, the substitute rule seems to have curtailed the recent increases in the tackling rate.

"This year, to date, tackles have actually dropped back for the first time in a number of years," AFL football operations manager Adrian Anderson said.

While hamstring strains continue to sideline players for the highest number of games each year, there was some positive news in the injury survey.

"The hamstring recurrence rate has dropped," Dr Seward explained. "It was up around 30 per cent some five or six years ago and it's now down to 13.

"That means the rehabilitation has got a lot better and the decision-making has got a lot better."

Despite a tightening of the rules regarding concussed players, Dr Seward does not expect next year's survey to reveal a rise in the number of games missed due to concussion.

"I don't," Seward said. "It may in fact be improving [the players'] opportunity to recover and we might see a reduction.

"It may not change much at all. And looking at that as a test to see if the change in guidelines have been successful would be quite wrong.

"It's really about managing it on the day and improving the general recovery of player during the week."

Anderson believes the AFL's stance on concussion has already had an impact on the treatment of players in grassroots competitions.

"It's really set a positive example at community level," he said. "The feedback has flowed back about how important it is that if a player is clearly concussed he does not go back out onto the ground."