A medico-legal conference in Dublin has heard that around 1,700 of the 3,500 people who had a hip implant, which is the subject of a recall, will need new surgery to replace the product.

Dr Thomas Joyce, a medical engineering expert at Newcastle University, said that a big problem was not just the mechanical failure of the DePuy ASR hip implant, but metal poisoning.

This is caused by the metal on metal contact between the ball and socket of the hip implant, which generates a fine metallic dust within the patient's own body and can cause inflammation around the joint and other health problems.

Last August, DePuy orthopaedics ordered a worldwide recall of its hip implant.

At the time, it said around 12% of the 3,500 Irish people affected would need the product replaced.

The conference, which was organised by law firm Malcomson Law, heard that the most common problems with the product are hip implant dislocation, infection, bone fracture and pain.

In a statement, DePuy Orthopaedics said its top priority is patient safety.

The company said it would cover all reasonable cost of new surgery and expenses faced by patients.

It has appointed an Irish firm, Thompson and Partners to manage the reimbursement scheme.