Minimally invasive microscopically assisted lumbar discectomy using the METRx X-Tube system

Abstract

Background and purpose

Lumbar discectomy with the METRx X-Tube system and operating microscope is a modification of microendoscopic discectomy. The aim of this study was to describe this method and present the results of treatment of the first 13 patients.

Material and methods

Under general anaesthesia and fluoroscopic guidance, a guidewire was placed over the inferior aspect of the superior lamina. A 2.5–3 cm midline skin incision was made, followed by paramedian lumbar fascia incision. Then, dilators were sequentially introduced (muscle-splitting approach). Finally, a tubular retractor was fixed directly over the interlaminar space. Further stages of the procedure were performed using an operating microscope and standard microdiscectomy equipment. The first 13 consecutive patients operated on using this method were analysed. Twelve patients were operated on at one level and 1 at two levels. Disc herniation was centro-lateral in 10 cases, lateral in 2 and central (broad-based) in 2 patients.

Results

Regression of radicular pain was noted in all patients. No postoperative complications were observed except for prolongation of wound healing in 2 patients. According to modified MacNab criteria, excellent late outcome was achieved in 8 patients and good in 4 patients. There were no cases of recurrent radicular pain or need for surgical revision for herniation recurrence. One patient was reoperated on because of low back pain (implantation of an interspinous spacer).

Conclusions

Microscopically assisted lumbar discectomy using the METRx X-Tube system seems to be safe and effective. This method combines the advantages of modern minimally invasive techniques while avoiding the limitations of endoscopy.