Introduction
Evidence & Methods
Interspinous spacers for spinal stenosis were initially developed as an alternative for patients medically unfit for open decompression. However, their use has expanded in some centers to be considered a general alternative to open decompression for the treatment of lumbar spinal canal stenosis. This matched-cohort study compares these two approaches.
For patients with moderate or severe stenosis, respectively, the interspinous device provided good outcomes in 60% and 31% of patients as measured by the Zurich Claudication Questionnaire (ZCQ). Following open decompression, results were good in 69% and 89%, respectively. Seventeen percent of the interspinous spacers required removal and revision to open decompression.
This independent study suggests that in cases of severe stenosis, open decompression affords better results than interspinous spacers. In light of reliably good outcomes with open decompression (as demonstrated in the SPORT and Maine spinal stenosis studies), the role for interspinous devices as a general treatment for lumbar spinal stenosis is yet to be determined.
—The Editors
The standard operative procedure for lumbar spinal stenosis is open surgical decompression. The first interspinous process implant was developed by Senegas et al. [1], who used the device also in lumbar stenosis but only to stabilize the motion segment after open decompression. In previous years, several interspinous devices have been developed to obtain indirect decompression of neural structures in lumbar stenosis by posterior segmental distraction. The most often used implant has been the X-Stop, which is inserted by an open approach centered on the interspinous space [2], [3], [4], [5], [6], [7], [8].
The Aperius, introduced in the clinical practice in 2007 (Medtronic, Memphis, TN, USA), has been the first interspinous device developed to be implanted percutaneously, usually under local anesthesia.
During the past few years, there has been a widespread use of the interspinous spacers in patients with central or lateral lumbar stenosis of any severity. But, the clinical results of these devices, implanted by open surgery or percutaneously, are still controversial [2], [3], [6], [7], [8]. Furthermore, only one study [9], carried out on very small groups of patients, compared the X-Stop with open decompression.
We compared the results of the Aperius implant with those of open decompression with the aim to better define the indications for the two types of procedures in patients with lumbar stenosis.