Discectomy, or microdiscectomy, is a procedure during which the surgeon removes a small portion of the disc that is compressing the nerve. This is usually done when there is leg or arm pain that radiates from the spine, caused by compression of the nerve. Even though the nerve is injured at the spine, it feels like the pain is coming from the leg or arm, because that’s what the brain thinks the nerve is reporting from. Radiologists may refer to a disc injury as a disc bulge, disc herniation, extruded disk, or even tear in the disc. The pain usually appears when the nerve is trapped between the disc and the ligaments and bones of the spine. The nerve then gets irritated, causing pain and numbness or even weakness in the area of the arm or leg that it usually travels to.
Discectomy surgery is usually done through a very small incision which can be the size of a dime or smaller. The blood loss from this operation is usually less than a teaspoon. The operation is done under a microscope, hence the name micro-discectomy. If done for the right reasons and performed correctly, micro-discectomy can be more than 95% effective in relieving pain and weakness immediately. The numbness, however, may persist a little bit longer. During the operation, the surgeon removes a very small amount of bone in order to see the nerve, which allows him to protect said nerve very well. By protecting the nerve, it can be pulled aside and the disc underneath removed. This way, the only structure that is exposed during the surgery is the one nerve that needs to be decompressed. The operation takes less than one hour and you can go home a couple hours after surgery. The pain from this operation is very minimal and easily managed with pain medication.
While damage to the nerve during this operation is very rare, there is a possibility of CSF leak. CSF is the fluid that is produced by the brain and soaks the brain, spinal cord, and nerves within the thin sac called dura. Sometimes the disc herniation itself tears this sac or it can be nicked during surgery. CSF leak can easily be repaired by a neurosurgeon who is trained in dealing with nerves.
By virtue of the fact that the nerve has been compressed, pinched, or stretched by a bulging disc, the nerve has already been injured. That is primarily why the nerve is painful or numb. Therefore it is clear that the nerve is right next to the disc. Naturally, the operation involves the disc as much as it involves their nerve.
If while viewing the operation the disc gets stretched too much or it is heated (laser surgery), then there may be consequences of nerve damage such as persistent pain that usually presents as hyper-sensitivity. This simply means that you may experience more pain than usual when you so much as brush the skin on your leg or arm. Generally speaking, over time this will resolve and the pain will go away. Sometimes a small dose of steroid pills may help the situation significantly by decreasing the inflammation and improving the pain quickly.
Handling the nerve appropriately during a discectomy surgery is extremely important. This operation is more about the nerves than it is about the disc. Neurosurgeons who are very familiar with the nerve tissue in the brain and spinal cord understand nerves the best. As such, neurosurgeons are extremely careful and concerned about the well-being and recovery of the nerve throughout the whole process. That is why when this operation is performed by experienced neurosurgeons their risk of damaging the nerve is extremely small. After such surgery, the resulting pain, weakness, and subsequent numbness will fade quickly. Interestingly enough, the numbness is the last to resolve. In the period of recovery while the nerve is waking up and tries to do what it usually does it is very common for our patients to experience occasional pain, tingling, or numbness.
It is important to note that sometimes the disc is so involved with the nerve that the application of a laser, which essentially is a heat source, can damage the nerve. It is imperative that you review your MRI with an experienced neurosurgeons who is able to recognize the dangers one may encounter during laser surgery. In some instances using a laser can permanently damage the nerve. Neurosurgeons who are experienced in looking at the nerves can assess the situation better and tell you if laser surgery is the right procedure or if a minimally invasive and microscopic open surgery would be more beneficial. Interestingly enough, the recovery from both are exactly the same. They both leave a very small scar. They both have very minimal blood loss. In both scenarios the patient is able to leave approximately one hour after the surgery.
Once again, to reiterate, neurosurgeons who perform spine surgeries are very comfortable operating around the nerves in the spinal cord. They are the most qualified doctors to repair the nerves if there is an injury to the nerves before or during surgery.
For an experienced spine surgeon, specifically neurosurgeons who are very used to operating in the brain through a small corridor, the size of the incision for an open discectomy is usually the size of a dime. This operation is of course performed under a microscope. You can imagine that if there was a lot of bleeding in a small space under microscope it would be impossible to see anything or operate. So, the blood loss from this surgery is very minimal; it is usually less than a teaspoon. Even then, we surgeons are hyper-vigilant about bleeding and make sure that our patients are not any medications or don’t have any conditions that make blood clotting difficult. In summary, the blood loss from a minimally invasive microscopic discectomy is really insignificant. We encourage you to look at the size of an incision on one of the patients on our website. You can also take out a dime from your pocket and look at it and imagine how small of an incision we are talking about.
With disc herniation there is injury to the nerve that presents itself as numbness in the area where the nerve should be feeling. This is usually extending from the spine all the way to the arm or leg. Sometimes our patients are not even aware that they have numbness. Doing a thorough examination in the office when tested with a small needle we discover that there are some areas that feel significantly less pain. This is an indication of damage to the nerve. Therefore, after removing the pressure on the nerve from the disc, it takes time for the nerve to heal itself and the numbness, therefore, takes some time to resolve. Pain usually resolves right away; however, numbness may take weeks to months to resolve. A general rule of thumb is that if you have been suffering from the discontinuation for one year, it takes one year for the numbness to go away. So it’s best to act quickly when it comes to damaged nerves.
For more information on the complications of disectomy, come back next week for Part 2.