by Richard Evans, FOXSports.com

Juan Martin del Potro was one of several players forced to retire at the Shanghai Masters. (Victor Fraile / Getty Images)

As far as the tennis world is concerned, this is getting uncomfortably close to a pandemic and needs to be addressed with intensity.

I know the ATP leadership is worried about it and, happily, the USTA is also examining the problem in detail. When I spent a day at a gathering of top USTA coaches at the Evert Academy in Boca Raton recently, I had the opportunity to study data the USTA had extracted from 861 junior players last year and the findings were alarming.

Between July 2007 and July 2008, 41 percent of all the players polled said they had having suffered at least one injury. Thirteen percent reported two or more injuries — and we are talking here about players between the ages of 10 and 17. Females had 57 percent of the injuries with males having 43 percent.

The USTA coaches were not expecting the data to be good, but they were shocked at the figures nonetheless.

"It's worse than we expected," admitted Tom Gullikson, one of the original members of the USTA Player Development Program.

Finding a solution should now be the primary goal of all tennis authorities throughout the game. The causes are readily apparent. Equipment has changed over the past decade, not so much with the increasingly powerful rackets but with the Big Banger strings which allow fiercely hit rallies to extend from six or seven shots to 14 or 15 on a regular basis. The added stress on the body is enormous.

And then there is the surface. Hardcourts are debilitating. Gullikson's colleague, Jose Higueras, has clay as well as hardcourts at his Palm Springs Academy and he will tell you how he feels after a day training on one or the other.

"After a day on clay I am fine," says Higueras, whose long coaching résumé includes a stint with Roger Federer. "After a day on hardcourts I can hardly get out of bed in the morning."

OK, so Higueras is in his 50s, but just because young players do not feel the effects so much does not mean that the damage is not being done. There is a growing realization that clay, for both tactical and physical reasons, is a far better surface on which to bring up young players.

"We will look into the possibility of putting the Orange Bowl back on clay at some stage," Player Development boss Patrick McEnroe told me.

Currently the Orange Bowl — the world's leading junior event — is played on hard courts at Crandon Park on Key Biscayne after being moved from its old clay court home at Flamingo Park on Miami Beach.

Examining the data in greater detail, the types of injury that show up make interesting reading. Overall, back injuries take the top spot with shoulders second, ankles third and knees fourth.

Injuries caused trouble for Rafael Nadal in the final three Grand Slams of 2009. (EMMANUEL DUNAND / Getty Images)

But for the Under 12s, shoulder problems make up 23 percent of the injuries with knees accounting for 22 percent. For the 15-16 age range, the leading problems are knees (18 percent) with backs and ankles tied at 17 percent. Wrist injuries, which seem to be getting more prevalent on the ATP tour, are constant throughout all ages at 9-10 percent.

For all the criticism leveled at it in the past, the USTA has now gathered a dedicated group of coaches who are clearly motivated, as well as open-minded, as they search for solutions. Jay Berger, Ricardo Acuna, Tim Mayotte, Kathy Rinaldi, Rodney Harmon and Richard Ashby to name just a few were involved in animated discussions about the best methods of teaching and nurturing the next generation from how to hit a serve to how much training should take place on the court as opposed to in the gym.

Trying to distill the complex problems facing this group is not easy, but perhaps one could highlight three areas of special concern — surface, strings and stress. The physical and the psychological are intertwined in the development of a champion, which is why it was good to see the eminent psychologist Jim Loehr, who has worked with so many players over the years, in attendance at Boca.

No young player will have a hope of succeeding if either the body or the mind cannot take the strain. It's a tough road to the top — tougher than many critics imagine.

Richard Evans, who commentated at Wimbledon on BBC Radio for 20 years, has been covering tennis since the 1960's and has reported on more than 150 Grand Slams. He is the author of 15 books, including the official history of the Davis Cup and the unofficial history of the modern game in "Open Tennis." He lives in Florida but is still on the tour 20 weeks in the year.