Lumbar fusion

What is a lumbar fusion?

This involves fusing two or more vertebrae together to achieve stability of that segment and allow full decompression of the compressed nerves.  It often requires metalwork to be inserted and can involve a posterior fusion, anterior fusion, or lateral fusion – the optimum method can be discussed with your surgeon.  Posterior fusions often have a decompression performed at the same time whilst anterior and lateral approaches often decompress the nerves by improving spinal alignment in a different way.  If you smoke, it is very important to stop well in advance since this could prevent the fusion from healing properly.

What does it involve?

You come to hospital on the day of the operation.  The procedure is performed using a general anaesthetic. 

Posterior instrumented fusion (with or without transforaminal lumbar interbody fusion):

An incision is made in the middle of your lower back; the length of this will depend on the exact operation required.  Some posterior fusions can be performed via minimally invasive approaches.  Screws are inserted into the bone and held together using rods.  The bone causing the nerve compression is removed from the laminae and facet joints to take the pressure off the nerves.  If an interbody cage is used, this will be inserted into the disc space with some bone graft.  Bone graft is laid around the vertebra to allow them to fuse together.  The wound is normally closed with dissolvable stitches under the skin.



A horizontal incision is made in the lower part of your tummy to allow approach to the front of your spine.  The disc is removed and a cage containing bone graft is inserted to allow the vertebra to fuse together.  The wound is normally closed with dissolvable stitches under the skin.



An incision is made over the side of your abdomen or flank to allow approach to the side of your spine.  The disc is removed and a cage containing bone graft is inserted to allow the vertebra to fuse together.  The wound is normally closed with dissolvable stitches under the skin.


What are the alternatives?

Continue with conservative measures: these include taking pain killers and staying as active as possible.  Performing physiotherapy exercises to reduce muscle spasm and keep your core muscles functioning is important.  Some people find their symptoms can resolve after an initial flare up whilst others find they can manage their pain by adapting their daily activities.

Nerve root injection: this puts some steroid around the painful nerves and aims to reduce the inflammation in this area.  It often helps sciatic pain but may not help the heaviness that some people experience with spinal stenosis.  It does not take away the underlying compression on the nerves or any instability in the spine so may only have a temporary effect.

Some surgeons advocate use of lumbar disc replacements or flexible ‘fusion’ systems.  If this is of interest to you, I would be happy to discuss this with you and refer you to someone who undertakes this, if required.

Post-operative recovery?

You will start to mobilise out of bed fairly soon after the operation.  Most people stay in hospital two or three nights after a posterior procedure, or one or two nights after a minimally invasive posterior, anterior, or lateral procedure.  When you go home, your back will be sore but this will quickly settle over the course of 3-4 weeks.  Changing your position regularly will help reduce muscle stiffness in your back.

You will have a dressing covering your scar for at least 2 weeks and this will be checked by a healthcare professional to ensure it is healing well.  Please do not remove this by yourself.

It is important to stay active and aim to take 2 or 3 short walks a day, gradually building up the distance you are walking.  It may be beneficial to start physiotherapy exercises and gentle core stability work at 4-6 weeks following the operation.

The fusion takes between six and nine months to consolidate so it is advisable to avoid strenuous activities, heavy lifting, and awkward twisting for at least the first two or three months to allow the fusion to start to form.

Medications: Continue taking your normal medications after the operation and, when the pain starts to improve, you can reduce them gradually one at a time.  There are some medications that should not be stopped abruptly so please check with your doctor about this.

Leg and back symptoms: Some people find their leg pain and heaviness disappears immediately, whilst others may find it takes a few weeks for any nerve inflammation to settle down.  The pain may disappear but some people do experience numbness down the leg, which often reduces in size over subsequent months.  If you have leg weakness due to nerve compression prior to the operation, this may slowly improve over the next 18 months; however, it may not return to normal.  Your back pain can slowly improve over the course of many months as your core muscles become stronger with regular physical activity and core stability work.

Post-operative problems: if you experience any unexpected symptoms, please seek medical advice.  Seek immediate advice if you cannot pass urine, develop numbness around your buttocks, or weakness in your legs; or if you feel unwell and the wound is red or oozing,

Returning to work: for office-based jobs, you may be able to return at around four to six weeks after the operation.  For more manual jobs, you may require light duties initially.  Consider returning to work part-time for the first one or two weeks to ensure you are comfortable.