Michael Barnes - Spine and Orthopaedic Surgeon

ISTHMIC SPONDYLOLISTHESIS

Key Points

• An isthmic spondylolisthesis is present in approximately 1 in 20 people.
• Only a minority of patients with spondylolisthesis ever require surgical treatment. During childhood or adolescence surgery may be required because of progression of the spondylolisthesis.
• During adulthood surgery is most often required because of the onset of sciatica (nerve pain in the lower extremities) due to narrowing of the exit zone for one of the spinal nerves. Usually this occurs in the 30s or 40s.
• Surgery involves the removal of bone from the back of the spine to create space for the spinal nerves and stabilisation of the two vertebrae by means of two pedicle screws in each vertebra joined by rods. A fusion is performed taking bone from the back of the pelvis through the same incision and laying it up and down each side of the spine.
• In most patients the inter vertebral disc is also excised and a spacer (cage) filled with bone graft inserted into the space between the vertebrae to assist fusion and creation of space for the exiting spinal nerves.
• Patients usually rest in bed the day after surgery and stand to take a few assisted steps on the second day after surgery.

 

Frequently Asked Questions

I am still experiencing some sciatica and numbness after my operation. Should I worry about this?
Only a minority of patients experience complete relief of sciatica from the time of the surgery. Most patients notice that it is much improved but there is still some aching in the leg because the nerve has a “memory” for the pain and remains slightly irritable. This usually resolves within a matter of weeks. The numbness usually resolves over weeks or months as the nerve recovers.

What do I do with the dressing?
The stitches are under the skin and will dissolve. The dressing is waterproof and you can shower in it. One week after leaving hospital simply peel it off as if it were a big “band aid”. Under the dressing you will find steri strips (tapes) holding the skin edges together. These may come off with the dressing but otherwise remove them one week later if they have not fallen off.

I have noticed a swelling on the left side of the incision. What is the cause of this?
Quite commonly swelling develops on the left side of the incision because this is where the bone graft is taken from and fluid accumulates between the incision and the back of the pelvis. This nearly always goes away within three or four weeks. This is a fairly common occurrence, is much more obvious in thin patients and does not mean there is an infection.

Will I need physiotherapy treatment?
Most patients who undergo surgery for isthmic spondylolisthesis do not have physiotherapy treatment; they simply increase their walking progressively and ease back into normal activity as their symptoms subside over a period of weeks or months. Some patients however, prefer to work with a physiotherapist and you should feel free to arrange physiotherapy if that is your preference.

When can I resume activities such as lifting?
The spine is held together by very strong screws and rods and cannot be damaged by activity, even lifting. Heavy lifting should obviously not be undertaken until your back feels strong enough. The patients who make the best recovery simply listen to their body and exercise common sense. As the weeks pass, activity is increased progressively but not to the point where it causes excessive pain which can slow your progress. Full recovery takes at least three to four months and sometimes six months or more.

 

General Information

An isthmic spondylolisthesis is present in approximately 1 in 20 people. It occurs because of the development of a bone defect at the back of the spine (the Pars) because of a stress failure of the bone in susceptible individuals.

A Pars defect is never present at birth but develops during childhood once walking commences, or during adolescence.

Most patients with an isthmic spondylolisthesis have no symptoms and do not realise they have the condition.

In a very small proportion of patients the spondylolisthesis can worsen during growth and development and rarely results in a complete slippage of the spine. Further slippage of the spine (progression of spondylolisthesis) only occurs to a minimal degree after the completion of growth, as the spine ages or degenerates.

Only a minority of patients with spondylolisthesis ever require surgical treatment. During childhood or adolescence surgery may be required because of progression of the spondylolisthesis.

During adulthood, surgery is most often required because of the onset of sciatica (nerve pain in the lower extremities) due to narrowing of the exit zone for one of the spinal nerves. Usually this occurs in the 30s or 40s.

Isthmic spondylolisthesis is very rarely caused by an injury but an injury may result in a nerve compression and the onset of symptoms. Once nerve symptoms are established surgery is usually required.

 

Surgical Procedure

Surgery is performed under general anaesthetic and usually takes approximately three hours. Surgery is performed using optical magnification (microsurgery) and involves the removal of bone from the back of the spine to create space for the spinal nerves and stabilisation of the two vertebrae by means of two pedicle screws in each vertebra joined by rods. A fusion is performed taking bone from the back of the pelvis through the same incision and laying it up and down each side of the spine.

In most patients the inter vertebral disc is also excised and a spacer (cage) filled with bone graft inserted into the space between the vertebrae to assist fusion and creation of space for the exiting spinal nerves.

 

Post Operative Course

Patients usually rest in bed the day after surgery and stand to take a few assisted steps on the second day after surgery. On day three patients are usually walking to the toilet and the urinary catheter is removed.

Patients usually go home on day four or five when their pain is under control with oral tablets, when they are able to get in and out of bed and up and down stairs.

Walking is the only exercise that is necessary when recovering from surgery for isthmic spondylolisthesis. Walking is increased progressively with the aim of walking 1km to 2km outside within two weeks of surgery. Some patients might also have physiotherapy treatment but this is not necessary for most patients.

Sitting or standing in one position can be uncomfortable for several weeks – simply move about or change position.

Most patients notice almost immediately there is a marked improvement in the nerve pain in the lower extremities but in some patients there is some residual pain which slowly resolves over a month or two.

Obviously there is lower back pain and stiffness created by the surgery which resolves over weeks, tailing off over several months. Complete recovery may take 6 months or longer.

You will leave hospital with a waterproof dressing which should be removed one week later. Simply peel off this dressing as if it was a “band aid”. The stitches under the skin resolve. No suture removal is necessary.

Driving is normally resumed within three to six weeks when it feels safe and comfortable.

 

Complications

A small proportion of patients develop a swelling to the left of the incision related to the bone graft. This nearly always resolves within three to four weeks.

Infection, nerve injury, spinal fluid leak requiring further surgery, or misplacement of pedicle screws requiring further surgery or failure of fusion requiring surgery are possible complications but occur in much less than 1% of patients and closer to 0% than 1%.

---

https://www.healthpoint.co.nz/private/orthopaedics/michael-barnes-spine-and-orthopaedic-surgeon/