Partial Disc Replacement with the PDN Prosthetic Disc Nucleus Device: Early Clinical ResultsShim, Chan Shik; Lee, Sang Ho; Park, Cheul Woong; Choi, Won Chul; Choi, Gun; Choi, Won Gyu; Lim, Sang Rak*; Lee, Ho YeonSpine: August 2003 - Volume 28 - Issue 0 - p 324-330 Focus Issue: Disc Arthroplasty: Article Abstract Author Information The aim of this study was to evaluate the efficacy of the PDN prosthetic disc nucleus device for the treatment of chronic discogenic back pain caused by degenerative disc disease. Among the 48 patients who underwent nucleus replacement surgery from January 2001 through May 2002, 46 patients were followed >6 months. The mean Oswestry Disability Index score was 58.9% preoperatively, and it improved to 18% at the 1-year follow-up. Visual Analogue Pain Scale scores improved from a preoperative mean of 8.5 to 3.1 after 1 year. The mean Prolo Scale score also improved from 5.2 preoperatively to 7.2 at 1 year. Major complications included four cases of device migration, requiring revision surgery, and infection in one patient. According to MacNab's criteria, results were excellent in 5 patients (10.9%), good in 31 (67.4%), fair in 3 (6.5%), and poor in 7 (15.1%). The overall clinical success rate was 78.3%. Nucleus replacement with the PDN device seemed to be effective in treating patients with chronic discogenic back pain caused by degenerative disc disease. Departments of Neurosurgery and *General Surgery, Wooridul Spine Hospital, Seoul, Korea Received January 5, 2003; accepted April 10, 2003. Address correspondence and reprint requests to Dr. Chan Shik Shim, Wooridul Spine Hospital, 47-4 Chungdam-Dong, Kangnam-Ku, Seoul, Korea. E-mail: firstname.lastname@example.org © 2003 Lippincott Williams & Wilkins, Inc.