Between each of our vertebra is a shock-absorbing spinal disc, which consists of a rubbery exterior known as the annulus and a jellylike "filling" called the nucleus. Herniated discs occur when a tear in the annulus allows some of the nucleus to leak out and bulge into adjacent nerves, irritating them.

Surgical treatments typically involve either removing the protruding nucleus and then sewing up the tear in the annulus – leaving the disc "deflated" – or refilling the disc with a replacement material, which may eventually also leak out through the unpatched hole.

Led by Cornell University's Prof. Lawrence Bonassar, scientists from the US and Italy have developed a procedure that combines the refilling with the patching. It's performed after a discectomy, which is the standard process for removing the leaked nucleus material.