Stenosis

WHAT IS STENOSIS

Stenosis is a really old Greek word for narrowing.  In the low back it refers to narrowing of the spinal canal causing pinching of the nerve roots.  Your nerve roots get their oxygen from the fluid around them. Severe narrowing of the canal restricts the fluid so the nerve roots can’t get the oxygen they need when you walk.

SYMPTOMS OF STENOSIS

This causes a strong feeling of back pain with radiation into the legs.  Sometimes the pain skips the back and is just in the legs.  Your legs feel heavy, weak, and numb.  Everything goes back to normal if you bend forward and rest.  Bending forward physically opens up the spinal canal, allowing the fluid to flow. Most people with stenosis notice that if they lean over a shopping cart in the grocery store that they can walk as far as they want without a problem.

CAUSES FOR STENOSIS

If you’ve live long enough, you will probably get spinal stenosis.  Think of the spinal canal as a room: the roof is the yellow ligament, the walls are the facet joints, and the floor is the disc space.  Joints normally get bigger with age.  (If you don’t believe it, and you are over 40, look down at your knuckles.)  The yellow ligament thickens with age as a result of wear and tear.  And discs are famous for “bulging” (Herniated Disc).  As a result of all these changes, with age and the roof is coming down, the walls are moving and, in the floor is rising.  It is not a surprise, then, that the spinal canal is getting smaller.  Some people don’t need to wait, they are born with a very narrow spinal canal. This condition is called congenital spinal stenosis.  You know you have it if one of your parents and all of your brothers and sisters have already had Laminectomy surgery.  You can also develop narrowing of the spinal canal due to a shift in the vertebrae.  The spine is a rigid ring.  If one band moves forward on the other one, it creates a kink in between.  This type of movement is called spondylolisthesis.  In very rare cases tumors, blood clots, and infections can cause narrowing as well. If you have one of those you shouldn’t be reading this; you should be getting help right away.

TREATMENTS FOR STENOSIS

The best way to treat spinal stenosis is to stay active.  Motion is lotion.  The more you walk, the less you hurt.  And the first is also true.  If something happens and you’re unable to walk, you’ll likely develop the pain.  The worst way to treat spinal stenosis is Epidural Injection.  It’s hard for the medication to get into the narrowed spaces around the spinal canal.  Experimental studies showed no benefit to epidural injection for patients with spinal stenosis.  So don’t waste your time having something done which we all know won’t work.  In most cases stenosis ultimately means surgery.

The easiest way to treat spinal narrowing is to raise the roof.  The bone on top of the yellow ligament which forms the roof of the spinal canal is called the lamina.  Removing the lamina is called laminectomy.  Surgeons have known for decades that drilling off the lamina creates more room for the spinal fluid, and usually eliminates her leg pain caused by spinal narrowing.  Laminectomy surgery for spinal stenosis is extremely effective.  Most patients wake up without the leg pain.  Experimental studies show patients with spinal stenosis to have surgery are far more functional, with less pain, than those who do not have surgery.

APPROACH TO STENOSIS

Laminectomy surgery is performed on patients with spinal stenosis using a “minimally invasive” approach.  The surgeon will make a 1/2-inch incision in the skin, and under x-ray guidance insert probes which gently dilate the muscles away from the lamina bone.  Looking down the microscope, through a tubular retractor, they then drill off the lamina bone, and then remove the ligament.  When necessary, they can remove herniated disc material at the same time.  The operation usually takes between 30 and 60 min.  It’s done on an outpatient basis.  Most people are largely recovered in 3 days, and fully recovered in a week.  There are restrictions after surgery.  They ask you to try not to bend, lift, or twist with more than 5 pounds for the first 3 weeks.  Most patients can lift 20 pounds after 3 weeks, and 40 pounds after 6 weeks.  After 12 weeks there are no restrictions.  There are extensive home exercise program we advocate for all patients.  If you’re unable to start out in a program, physical therapy may be needed as a bridge.  Most of our patients are back to light work after a week, moderate duty after 3 weeks, and heavy work after 12 weeks.