Clinical outcome following DIAM implantation for symptomatic lumbar internal disk disruption: a 3-year retrospective analysis

Kang Lu,1 Po-Chou Liliang,1 Hao-Kuang Wang,1 Jui-Sheng Chen,1 Te-Yuan Chen,1 Ruyi Huang,2 Han-Jung Chen1,3 1Department of Neurosurgery, E-Da Hospital, 2Department of Family Medicine, E-Da Hospital, 3Department of Neurosurgery, E-Da Cancer Hospital, College of Medicine, I-Shou University, Kaohsiung, Taiwan Background/objective: Internal disk disruption (IDD), an early event of lumbar disk degeneration, is the most common cause of low back pain. Since increased intradiskal pressure (IDP) is associated with symptoms and progression of disk degeneration, unloading a painful disk with an interspinous process device (IPD) is a rational treatment option. The goal of this study was to evaluate the effectiveness of dynamic stabilization with an IPD in the treatment of symptomatic IDD of the lumbar spine. Patients and methods: Patients with symptomatic IDD were treated with implantation of an IPD, the device for intervertebral assisted motion (DIAM). Diagnosis of IDD was based on typical MRI finding of posterior annular high-intensity zone and positive provocative test on discography. IDP was analyzed intraoperatively. Axial back and leg pain was evaluated with visual analog scale, functional status with Oswestry Disability Index, and final clinical outcomes with Odom criteria. Data from 34 patients followed up for at least 3years were collected. Results: DIAM implantation significantly reduced IDP (n=11, P