Interspinous implants: are the new implants better than the last generation? A review.
OBJECTIVE
Interspinous process devices (IPDs) are used in the surgical treatment of lumbar spinal stenosis. The purpose of this review is to compare the first generation with the next-generation devices in terms of complications, device failure, reoperation rates, symptom relief, and outcome.


RESULTS
Thirty-seven studies were included from 2011 to 2016. Device failure occurred at a mean of 3.7%, with a lower tendency to happen with next-generation IPDs. Reoperations occurred at a lower rate with the next-generation devices, with a mean follow up of 24 months (3.7% vs. 11.1%). The clinical outcome is not influenced by the type of IPD. The long-term functionality of these devices is questionable, with radiologic changes and recurrence of symptoms often seen by 2 years following implantation. Next-generation devices do not appear to be subject to the same "bounce back" effect of symptom re-emergence after several years.
Department of Neurological Surgery, Thomas Jefferson University, 909 Walnut St, 3rd Floor, COB Bldg, Philadelphia, PA, 19107, USA.
Michael
M
Pintauro
Department of Neurological Surgery, Thomas Jefferson University, 909 Walnut St, 3rd Floor, COB Bldg, Philadelphia, PA, 19107, USA.
Alexander
A
Duffy
Department of Neurological Surgery, Thomas Jefferson University, 909 Walnut St, 3rd Floor, COB Bldg, Philadelphia, PA, 19107, USA. payman.vahedi@gmail.com.|Department of Neurosurgery, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran. payman.vahedi@gmail.com.
Payman
P
Vahedi
Department of Neurological Surgery, Thomas Jefferson University, 909 Walnut St, 3rd Floor, COB Bldg, Philadelphia, PA, 19107, USA.|Division of Neurosurgery, Walter Reed National Military Medical Center, Bethesda, MD, USA.
George
G
Rymarczuk
Department of Neurological Surgery, Thomas Jefferson University, 909 Walnut St, 3rd Floor, COB Bldg, Philadelphia, PA, 19107, USA.
Joshua
J
Heller
Canal stenosis; Coflex; Interspinous device; Lumbar; Spine; X-Stop