HOOFDORP: FIFPro has warned that more than one in three former professional footballers over 40 are suffering knee problems amid concerns by the world players’ that current players are risking their long-term health or are unaware of the lasting effects of serious knee injuries.

A FIFPro study among 400 active and 900 former professional footballers indicated that 35pc of ex-players above 40 are suffering from knee osteoarthritis (a degenerative joint disease). That compares with eight to 13pc of the general population.

Footballers are 2.5 times more likely to suffer from knee osteoarthritis with every severe knee injury or knee surgery they had during their career.

“I know some old players who cannot even walk. They are cripples,” Pontus Kamark told FIFPro. The 48-year old Swedish World Cup veteran quit when he was 32 after three cruciate ligament surgeries. “My doctor noticed that my knee cartilage was almost gone. He advised me to stop.”

Only two months earlier Kamark had declined an invitation for Sweden’s 2002 World Cup squad because he did not feel fit enough. “I took the doctor’s advice. I considered my future health and wanted to be active, play ice hockey, tennis and golf for the rest of my life.”

Kamark, who played at IFK Goteborg and Leicester City, is still very active, but he said some of his peers have not been so lucky. Hakan Lindman, who played for Malmo and Anderlecht “has two plastic knees and can barely walk.”

Dr Vincent Gouttebarge, FIFPro’s chief medical officer, said club medical staff need to do more during a player’s career to prevent osteoarthritis in later life. Gouttebarge also suggests after-career consultation would help players strengthen their knees by following a healthy lifestyle and a fitness programme.

Gouttebarge said: “The results of the study are a confirmation that there are often serious, long term effects from knee injuries. This is the first research into knee osteoarthritis that includes active players and it gives us a clear picture of how cartilage damage evolves.”

Malmo defender Rasmus Bengtsson coped with knee problems for a year before opting for surgery.

He said: “The last sixmonths I played with huge pain. First I took painkillers, later on I had cortisone injections. When these did not help anymore we decided on the operation.”

The cartilage was removed from his left knee and recovery took 10 months.

Bengtsson played with pain because he had just joined Malmo and wanted to prove himself. “When you are young or moving to a new club, it would be helpful if physios hold you back when you are not fit. It is very difficult for a player to say that he does not want to play.”