Efficacy of the Wallis interspinous implant for primary lumbar disc herniation : a prospective randomised controlled trial


Published online: Sep 27 2017

Honglin Gu, Yunbing Chang, Shixing Zeng, Yonghong Gao, Shiqiang Zhan, Qiujian Zheng

From the Department of Orthopedics, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, P.R. China

Abstract

Purpose : To investigate the efficacy of the Wallis implant after lumbar discectomy compared with discectomy alone for primary lumbar disc herniation. Seventy-seven patients with primary lumbar disc herniation were randomly assigned to undergo either posterior lumbar discectomy with (n=40, Wallis group) or without (n=37, control group) Wallis implantation. The primary outcomes were visual analogue scale score, Japanese Orthopedics Association score, and Oswestry Disability Index. The secondary outcomes were intervertebral disc height, range of motion of the operated segments, complications, and operating time. The primary outcomes at 1 week after treatment (P> 0.05) were not different between groups. The Wallis group had better scores at 12 months (P< 0.05) and the last follow-up visit (P< 0.05), higher disc height (P< 0.001), and significantly longer operating time (P =0.006) than the control group. Combined treatment appears beneficial for pain relief and lumbar function improvement by maintaining intervertebral disc height and limiting the range of motion of the spine compared with lumbar discectomy alone. However, its actual clinical benefit remains controversial because of the longer operating time and the relatively small difference in the visual analogue scale score and Oswestry Disability Index between the groups.