Minimal Invasive Surgery (MIS) for Lumbar Instability

Abstract

Open lumbar arthrodesis procedures require significant exposure of the spine, which may result in ischemic damage and subsequent atrophy of the paraspinal musculature, resulting in prolonged back pain. Terminology as to what should be considered a “minimally invasive” (or rather, less invasive) approach to the lumbar spine has been vigorously disputed since early attempts were made to reduce the clinically perceived impact of open lumbar fusion. In an effort to define the core characteristics of a less invasive approach to lumbar arthrodesis, a multinational panel of European spinal surgeons has recently stated “a muscle sparing surgical technique that, using an intermuscle or transmuscle splitting approach, minimizes the detachment of the lumbar fascia and of the paraspinal muscles, while addressing a spinal pathology and allowing placement of instrumentation,” may be considered less invasive (Fig. 34.1). In a mini-open technique, instruments are placed using direct vision of target structures via a less invasive muscle-sparing approach, whereas a percutaneous technique utilizes radiographic or navigation guidance to place instrumentation via stab incisions without direct vision of target structures. Therefore, in essence, emphasis is clearly put on soft tissue sparing and minimizing surgical complications as opposed to simply limiting the length of the skin incision. The ultimate goal of less invasive lumbar arthrodesis is improvement of overall treatment success rates by combining (a) reduction of intraoperative blood loss; (b) reduction of operative site pain, infection, and wound healing problems; (c) acceleration of postoperative recovery and expedited return to work; and (d) potential reduction of long-term sequelae of open arthrodesis such as adjacent segment disease.