Minimally Invasive Spine Surgery

Lumbar Discectomy/ Spine Fusion, Interbody Fusion/Herniated Disc

When nerves in the lumbar spine are pinched, as may occur in the case of a herniated disc or lumbar spinal stenosis, pain may radiate down the lower extremities.  This is known as lumbar radiculopathy.  In more extreme cases, weakness of the lower extremities may occur, and in more critical conditions, a patient may lose bowel and bladder control.  Sometimes, all that is needed is a discectomy surgery (minimally invasive surgery), which involves removal of the herniated lumbar disc, and some of the lumbar disc material between the vertebral bodies.  At other times, a lumbar decompressive laminectomy surgery (minimally invasive surgery)  is required for a broader decompression of the nerves.  At times, the spine may become unstable, either preoperatively as a result of injury or degeneration, or during back surgery, as a result of the extensive bone removal which is sometimes required. 

We will discuss back surgery (minimally invasive spine surgery)  which consists of a lumbar discectomy or lumbar laminectomy to relieve radiculopathy.  We will also cover surgery for lumbar spine fusion.  Much of this will be done through a minimally invasive approach.  (Images were provided by Medtronic, Inc.)

When performing a minimally invasive spine surgery (back surgery), such as a discectomy, laminectomy, spine fusion, or minimally invasive surgery, the patient is lying on their abdomen, supported in a variety of ways.  The patient may be positioned on gel rolls, or on a Wilson frame, or on an OSI or Jackson table, which are designed specifically for surgery on the spine.  For lumbar surgery, an incision is made over the lumbar spine.  The exact position and length of the incision depends upon what needs to be done.  After the incision is made, the muscles are pulled away from the spine.

Below, we see an open back (spine)  surgery, with retractors in place, pulling muscle and fat (adipose tissue) to the side, so that the lumbar spine is exposed.  An instrument is used to help with the removal of the lumbar facet.

A tubular dilator is passed down to the lumbar spine for the minimally invasive surgery on lumbar the spine. The bottom portion of the tubular retractor is docked on the lumbar lamina.

Below is the view which the surgeon has (during a minimally invasive spine surgery), with the lumbar nerve root seen.  The surgeon is performing a discectomy, which is a removal of the lumbar disc.  The view is what the surgeon would see while looking and working through the tube.

Below, a lumbar disc distractor is placed within the disc space.  This helps to maintain the height of the lumbar disc space on one side, while the other side is being prepared.

Pedicle screws may be placed within the pedicles of the lumbar spine, and on the opposite side, to help create a working channel.  Pedicle screws are screws which go into the pedicles, and provide a rigid and stable construct to which rods may be attached.  The rod may then be attached to a pedicle screw placed at another spinal level.

A rotating cutting device is placed within the disc space to clean out some of the lumbar disc material. 

Curettes are used to scrape the endplates of the vertebral bodies, further cleaning out the disc space.

A rasp is used to roughen up the edges of the bone in the vertebral body, which will place the eventual intervertebral body graft in contact with healthy bleeding vertebral body. Below, on the left, this is done through an open insicion, whereas on the right, it is done through a minimally invasive approach tubular guide.  On the left, the spine surgery is being accomplished through a Wiltse approach.  The Wiltse approach involves an incision off of the midline, with dissection through the various muscle layers of the back.

Below, we see a minimally invasive retractor in place.  On the right is an x ray of a disc distractor in place, and pedicle screws and a rod are seen.

Below, a trial is performed to find the appropriate sized intervertebral body implant.  This allows the surgeon to find the appropriate graft for the placement of a posterior lumbar interbody fusion (PLIF).  A PLIF is a graft placed between the vertebral bodies, which will allow one body to fuse to the adjacent one.

Next, the intervertebral cage is deployed into the intervertebral disc space.  Bone graft is packed around the cage.

Pedicle screws are placed on both of the lumbar spine, to assist with the spine fusion.

Pedicle screws and rods are placed on both sides, to promote lumbar spine fusion.