Preliminary results of the interspinous implants for treatment of lumbar degenerative diseases

Abstract

Objective To describe our initial experience and evaluate the preliminary results as well as the possible complications of interspinous implant (device for intervertebral assisted motion, DIAMTM) in managing symptomatic lumbar degenerative disorders. Methods A group of 22 patients were analyzed ret-rospectively. Fourteen female and eight male patients were treated. Mean age was 38.5 (range, 24 -59) years. They had clinical evidence for lumbar facet joint pain and a facet joint injection therapy had good result. Pre-operatively MRI and CT scan was done to evaluate the lumbar spinous process, lumbar disc and facet joints. Fourteen patients were operated at single level, eight patients at double levels. Radiographic imaging, pain scores, and clinical assessments were obtained at 24th week, 66th week postoperatively. Results Pa-tients were evaluated clinically through the Odom's criteria: 31.8% (7 patients) excellent, 45.4% (10 patients) good, 4.5% (1 patient) fair and 18.1% (4 patients) poor results. A significant difference was observed in im-provement of visual analogue scale that decreased from preoperative mean 7.09±0.92 to postoperative mean 3.23±1.82. Statistically significant differences were noted in neural foraminal height and posterior disc height when comparing patients pre-and postoperatively. For the follow-up period, no migration and loosening of implant was found, and no revision surgery was needed in all cases. Conclusion In this preliminary result, it could be observed that the DIAMTM prosthesis can offer a pain relief in well selected patients suffering lum-bar facet joint pain. The indication should be very strict. The implant acts as: 1) A shock absorber, give dis-traction of the neuroforamina, realign facet interface; 2) Restore posterior column height and share in load transmission. Key words: Lumbar vertebrae; Low back pain; Zygapophyseal joint; Prostheses and implants; Treat-ment outcome