The term “minimally invasive”, when describing a surgical procedure, refers to a technique using small incisions to gain access to the particular area of the body needing treatment. By avoiding a larger incision, there can be less force from the retractors on the surrounding tissues, less tissue dissection, and better preservation of the surrounding blood supply to the tissues in the operated area. Ideally, these factors lead to quicker healing and a recovery with less pain, although these differences have not been proven conclusively. For an “open” procedure (or non-MIS), the surgical wound is larger and more dissection is required. Retraction on the muscles, when kept in place during a long procedure, has been shown to cause damage to these muscles that may become permanent.
The comparison between minimally invasive and open surgery can be made when describing a lumbar fusion. This procedure typically has the patient lying face down during the surgery, with the work done on the back side (posterior.) With an open case, the incision is usually in the midline and the muscles are spread to the sides by retractors. The natural tendency of the muscles is to return to the midline. That means the force can be fairly high at the spot where the retractor is in contact with the muscles. If the surgeon tries to minimize the length of the incision with the open technique, he/she may have to use the retractors to spread harder so they can see the areas where the work needs to be done. These retractor-induced forces can be reduced somewhat by, paradoxically, making a longer incision.
A tubular reactor is usually used with the minimally invasive approach. After the appropriate level of the spine is identified with x-ray, first small, then sequentially larger tubes are placed, one over another, to dilate (expand) the opening. The force on the muscles is distributed more equally in a direction, like spokes on a wheel, with less localized pressure. This creates less potential for muscle damage.
While you may feel an attraction to the advantages of a minimally invasive approach, you still need to understand all aspects of the surgical plan in order to make an informed decision. Youeed to know the rationale behind the proposed surgery, the chances of success and expected rehab course, and, most importantly, the risks. Don’t hesitate to contact Spine Center of Texas if you want to know more about minimally invasive spine surgery.