​When Mr Yeo Jia Liang, 36, woke up one morning, he suddenly felt a sharp, excruciating pain in his back and could not get out of bed. Mr Yeo, a project manager in the IT industry and an avid sportsman, found out he had isthmic spondylolisthesis, a spinal disorder where a vertebra (disk of bone) in the lower spine cracks and then slips forward and onto a bone below it, creating a painful condition that eventually requires surgery.

Luckily for Mr Yeo, doctors were able to put him back on his feet by using a special bone 'fertiliser', which when used with conventional techniques helps bones heal faster.

Spinal fusion to treat spondylolisthesis

Previously, patients with spinal disorders such as isthmic spondylolisthesis who opted for surgery only had the option of conventional spinal fusion or repair, said Clinical Associate Professor Tan Seang Beng, Senior Consultant and Director of the Spine Service at the Department of Orthopaedic Surgery at Singapore General Hospital (SGH), a member of the SingHealth group. This process fuses the affected vertebrae via two surgical procedures.

Spinal fusion surgery requires two procedures

The first procedure involves placing titanium rods, screws and cages, to keep the affected vertebrae in place. The second procedure involves taking bone from the pelvis and grafting it onto the vertebrae to help fuse them together. The practice of harvesting bone from the pelvis not only traumatises the patient, but often also causes severe pain that lasts long after the operation.

Another drawback of bone grafts is that they do not always produce successful bone fusion. In addition, they increase the time patients spend in surgery and can lead to an increased risk of infection and blood loss. Patients usually end up having to stay in hospital longer, and it often takes a year or more to recover fully from spinal fusion surgery.

Combining bone 'fertiliser' with spinal fusion

Mr Yeo had the improved surgery which combines a bone 'fertiliser' with the spinal fusion procedure. This unique medical innovation involves bone morphogenetic proteins (BMPs), which are genetically engineered proteins derived from human genes. These proteins attract stem cells (which are able to change into different types of cells) from other parts of the body to the damaged area and encourage the growth of bone cells.

Using BMP is a less invasive way to treat spinal disorders such as spondylolisthesis. After metal implants are placed in the patient’s spine, BMP is applied to stimulate the cells to make more bone and encourage bone fusion. This reduces the need for grafting, meaning that patients need not endure a second operation to harvest bone grafts from their pelvis.


This greatly decreases the overall amount of pain involved, and also speeds up the bone healing process, so patients can recover within a shorter period and return to a productive lifestyle, explained Dr Tan. BMP is also recommended in cases where conventional spinal fusion may not work; it is especially helpful in instances where the quality of bones in some patients may have deteriorated due to age.

Read on for more information on spinal fusion surgery and its outcome.

Ref: W09