Hampson suffered the injury during an Under-21 scrummage session at Northampton's Franklin's Gardens and he was due to have surgery later on Tuesday to realign his neck using traction.

The 20-year-old, who plays for Leicester Tigers, was treated immeditely after the incident on the pitch before being transferred by ambulance to the intensive care unit of Northampton General Hospital.

The Rugby Football Union released a brief statement and England Under-21 manager Pete Drewett said: ''Our immediate concerns are with Matt and his family.

''He is getting the best treatment available and we aim to make a further announcement following his operation.''

Hampson has been a regular in the England squad for the Under-21 RBS 6 Nations and he started at tight-head in last week's victory over Italy.

He was was busy preparing for Friday's final match, against Scotland in Northampton, when the accident occurred.

Hampson had been targeted as a player with a bright future after signing for Leicester's Academy at Under-16 level.

He became an apprentice at the beginning of the 2001-02 season and is one of five development squad players who trained with the Leicester first team during the summer.