title: Foreign Body Reaction after Implantation of a Device for Intervertebral Assisted Motion.
abstract: The device for intervertebral assisted motion (DIAM) is a dynamic implant that consists of a silicone bumper enveloped by a polyethylene terephthalate (PET) fiber sack. Silicone and PET were used because of their biological inertness, but repetitive motion of the spine can cause wear on the implant nonetheless. The purpose of this study is to report a case of foreign body reaction (FBR) against a DIAM. A 72-year-old female patient presented with lower back pain and both legs radiating pain. She had undergone DIAM implantation at L4-5 for spinal stenosis 5 years previously. The intervertebral disc space of L4-5, where the DIAM was inserted, had collapsed and degenerative scoliosis had developed due to left-side collapse. MRI showed L3-4 thecal sac compression and left L4-5 foraminal stenosis. The patient underwent removal of the DIAM and instrumented fusion from L3 to L5. During surgery, fluid and granulation tissue were evident around the DIAM. Histopathology showed scattered wear debris from the DIAM causing chronic inflammation due to the resulting FBR. A FBR due to wear debris of a DIAM can induce a hypersensitivity reaction and bone resorption around the implant, causing it to loosen.
authors.affiliation: Department of Orthopaedic Surgery, Jeju National University Hospital, School of Medicine, Jeju National University, Jeju, Korea.
authors.forename: Jun-Yeong
authors.initials: JY
authors.lastname: Seo
authors.affiliation: Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Kee-Yong
authors.initials: KY
authors.lastname: Ha
authors.affiliation: Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Young-Hoon
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Joo-Hyun
authors.initials: JH
authors.lastname: Ahn
keywords: Device for intervertebral assisted motion; Foreign body reaction; Polyethylene terephthalate; Silicone