Micro Lumbar Decompression for Lumbar Spinal Stenosis

Spinal stenosis was described, for the first time, as one of the causes of neural compression by Bailey and Casamajor (1) in 1911. Later, in 1954, it was described by Verbiest (2) as the typical clinical presentation of bilateral neurogenic claudication, which is provoked by prolonged standing and lower back extension and relieved by sitting and flexing the lumbar spine. Degenerative lumbar spinal stenosis is a progressive spinal disease which is common in the elderly population and characterized by hypertrophy of the ligamentum flavum, degeneration of the intervertebral disc, and hypertrophy of the facet joint. Traditionally, the treatment of spinal stenosis has been wide laminectomy, which allows decompression of the neural structures by unroofing the spinal canal. The success rate of the procedure is between 62-70% due to postoperative iatrogenic spinal instability. Consequently, the minimally invasive approaches such as partial interspinous laminectomies, modifications of spinous process osteotomies, bilateral laminotomy, and unilateral laminotomy are described. Young et al. (3) described unilateral laminotomy for bilateral micro decompression of lumbar spinal stenosis technique in 1988. Their approach was modified by McCulloch (4) in 1991 and described as microsurgical fenestration technique. The main purpose of this minimal invasive surgical technique is to maintain spinal stability by performing enough decompression of dural sack and effected nerve roots. In this surgical technique paraspinal multifidus muscles retract ipsilaterally and muscle structure of the opposite side is protected. Therefore, iatrogenic muscle trauma is kept in a minimal level. Similarly, inter-/supraspinous ligaments are protected; since unilateral micro decompression is performed in spinal canal facet joints and joint capsule of the opposite side is also protected. As a result, the risk of postoperative iatrogenic segmental instability is minimized. Other advantages of unilateral micro lumbar decompression include a reduced operative time, fewer intraoperative complications, minimal blood loss, short hospitalization and immediate recovery. In conclusion, unilateral micro lumbar decompression gives better surgical results.