Q: What is minimally invasive spine surgery?

A: The American Academy of Orthopaedic Surgeons (AAOS) has recently published an instructional course lecture for spine surgeons on the subject of minimally invasive spine surgery (MISS).

They bring us all up-to-date on the current state of minimally invasive spine surgery (MISS). MISS means, it is a way to reach the spine through the skin and soft tissues without cutting through all the muscles and many tendons. Instead of a large, open incision the surgeon makes small slits in the skin and slips a tube down to the target site (usually vertebral bone or disc).

Surgical tools needed to perform any of the procedures mentioned reach the target tissue through the tube. A tiny TV camera on the end transmits real-time pictures to a screen to guide the surgeon. That sounds very simple and in a way, it is (compared to open incision and dissection or cutting through all the soft tissues).

The replacement of self-retaining retractors (used during an open procedure) by the tubular retractor (used during a minimally invasive spinal surgery) was a major turning point in spinal surgery. The self-retaining retractors pulled the soft tissue apart after incisions were made. This allowed the surgeon to gain access to the spine.

But the force of the self-retaining type of retraction caused crush injuries to the muscles, blood vessels, and nerves. Replacement with the tubular retractor changed all that. Loss of blood supply to the muscles and damage to the nerves often meant the patient never regained the muscle strength needed to support the spine. The result was often chronic back pain and weakness, a condition referred to as failed back surgery syndrome.

Studies show that even at the cellular level, the goals of minimally invasive spinal surgery (to reduce soft tissue injury and speed recovery) are met. Blood studies show that all levels of biomarkers for tissue injury return to normal much faster after minimally invasive surgery.

According to this course lecture on minimally invasive spinal surgery, the technique is replacing the traditional open incision approach. There is more and more evidence to support minimally invasive procedures.

Studies show that patients recover faster with less time in the hospital and fewer costs. They return to daily activities and work sooner, too. In the hands of a skilled surgeon, the procedure is safe and effective with less tissue damage, less blood loss, and less post-operative pain.

Reference: Choll W. Kim, MD, PhD, et al. The Current State of Minimally Invasive Surgery. In The Journal of Bone and Joint Surgery. March 16, 2011. Vol. 93-A. No. 6. Pp. 582-596.