title: The combined use of a posterior dynamic transpedicular stabilization system and a prosthetic disc nucleus device in treating lumbar degenerative disc disease with disc herniations.
abstract: BACKGROUND
  Prosthetic replacement of spinal discs is emerging as a treatment option for degenerative disc disease. Posterior dynamic transpedicular stabilization (PDTS) and prosthetic disc nucleus (PDN) devices have been used sporadically in spinal surgery.
  
  
  METHODS
  This was a prospective study of 13 patients averaging 40.9 years of age with degenerative disc disease who underwent posterior placement of a PDN with a PDTS. The Oswestry low-back pain disability questionnaire and visual analog scale (VAS) for pain were used to assess patient outcomes at the 3rd, 6th, and 12th postoperative months. Lumbar range of motion was evaluated using a bubble inclinometer preoperatively and at 12 months postoperatively. Radiological parameters including lumbar lordosis angle (LL), segmental lordosis angle (α), disc height at the operated level (DHo), and disc height of the adjacent level (DHu) were evaluated. A typical midline posterior approach for complete discectomy was followed by the simultaneous placement of the PDN with PDTS.
  
  
  RESULTS
  Both the Oswestry and VAS scores showed significant improvement postoperatively (P < .05). There were no significant differences in LL, α, DHo, and DHu parameters. We observed complications in 3 patients including 2 patients who had the PDN device embedded into the adjacent corpus; 1 had massive endplate degeneration, and the other experienced interbody space infection. In 1 patient, the PDN device migrated to one side in the vertebral space.
  
  
  CONCLUSIONS
  The use of a PDN in combination with posterior dynamic instrumentation can help to restore the physiologic motion of the anterior and posterior column and could help to establish posterior dynamic instrumentation as an important treatment of degenerative disc disease. Theoretically this concept is superior, but practically we need more advanced technology to replace disc material. Because this study examined the combination of the PDN and stabilization instrumention, the results cannot be compared with those reported in the literature for either PDN alone or dynamic screws alone.
  
  
  METHODS
  Prospective cohort study with good follow-up (level 1b).
authors: Neurosurgery Department, VKV American Hospital, Istanbul, Turkey.
authors: Mehdi
authors: M
authors: Sasani
authors: Neurosurgery Department, VKV American Hospital, Istanbul, Turkey.
authors: Ahmet Levent
authors: AL
authors: Aydin
authors: Neurosurgery Department, VKV American Hospital, Istanbul, Turkey.
authors: Tunc
authors: T
authors: Oktenoglu
authors: Neurosurgery Department, Faculty of Medicine, Canakkale 18 March University, Canakkale, Turkey.
authors: Murat
authors: M
authors: Cosar
authors: Physical Therapy and Rehabilitation Department, VKV American Hospital, Istanbul, Turkey.
authors: Yaprak
authors: Y
authors: Ataker
authors: Neurosurgery Department, Pendik State Hospital, Istanbul, Turkey.
authors: Tuncay
authors: T
authors: Kaner
authors: Neurosurgery Department, VKV American Hospital, Istanbul, Turkey.
authors: Ali Fahir
authors: AF
authors: Ozer
keywords: Dynamic instrumentation; degenerative disc disease; lumbar disc herniation; non fusion treatment; prosthetic disc nucleus