Case Studies Series: Lumbar Instability after Prior Surgery

This patient was a 32-year-old with a history of multiple prior back surgeries. I met her in early 2017 when she presented with severe lower back pain and bilateral leg pain. Her pain was basically preventing her from living a normal life. Walking any distance caused a rapid increase in her pain. Her leg pain went down the back of both legs and resulted in numbness in the feet. 

Her surgical history dates back to 2013 when she had an acute disc herniation at L4/5 that caused weakness in both legs, numbness in her feet, numbness in her perineum (medical term for an area of the anus and genitalia), as well as difficulty with bladder function. This constellation of symptoms is called cauda equina syndrome. She had a laminectomy and decompression at that time. Her leg pain, numbness and bladder dysfunction improved following that operation. Unfortunately, she did continue to have some residual numbness in her feet.

Her symptoms recurred in 2015. She had another surgery by the same neurosurgeon as had done her surgery prior. This second surgery was at the L4/5 again and was a revision laminectomy and decompression. Her pain improved but recurred within a few months. Her symptoms then progressed over the next two years until she saw me. 

When I saw her, she was basically unable to function due to her chronic pain. We discussed her symptoms and looked at her imaging. From the first appointment I recommended surgery. My recommendation was for a decompression and instrumented fusion as an overall plan but we spent a great deal of time discussing the various approaches. Do we do an open approach from the back to decompress and fuse? Do we put bone graft in the disc space to aid in the fusion? Do we do an anterior approach to put bone graft in the disc space? 

Her imaging showed several significant pathologies. She had a recurrent disc herniation (as well as extensive scar tissue) at the L4/5 level. The disc herniation was extending laterally into the neural foramen and compressing both nerve roots. This is relatively unusual. This was causing the leg pain in both legs. It also explained the weakness in her toes and the numbness in her feet. 

She also had an absence of the pars (bone bridge connecting the vertebral body to the back of the spinal canal) on both sides at the L4 level. This would explain her lower back pain. She did not have any gross instability.

After discussing the various surgical options, no matter which option we picked, the basic criteria for the surgery remained that we had to decompress her nerve roots and we had to fuse the L4/5 level.

Because of her prior surgeries, extensive scar tissue and collapsed disc space, I recommended an open approach for decompression followed by an open instrumented fusion.

She underwent an L4/5 decompression, discectomy, and instrumented fusion. Following the surgery, she felt better immediately. She lost about 20 lbs and has no lower back pain or leg pain. Her numbness has almost completely resolved and she is exercising and strengthening her back.

She is now six months out from surgery and is walking, running, doing Pilates, and working full time. She is not quite at the level she was prior to the initial disc herniation but she is significantly better than she has been in the last four years. Overall, her quality of life is dramatically better.