nitinol and Intervertebral-Disc-Degeneration

Retrospective case series study.. To clarify the results of a long-term (30 yr) follow-up study of artificial disk replacement (ADR) for the treatment of cervical disk disease.. The use of the ADR procedure has become widespread during the past 10 years. Its purpose is to preserve motion of the functional spinal unit. However, the long-term results are unknown.. Thirty-seven patients underwent ADR between 1980 and 1985 in the Department of Orthopedic Surgery, Changzheng Hospital. Twenty-one patients, who had a complete follow-up, underwent radiographical evaluation to detect heterotopic ossification, segmental range of motion, and adjacent segmental changes. In addition, patients were asked to complete preoperative and postoperative visual analogue scale, neck disability index, and 36-Item Short Form Health Survey questionnaires for evaluation of neurological function and pain severity. The occurrence of adverse events and reoperations was examined and these parameters served as indicators of device safety.. Twenty-one patients had a complete follow-up average of 30 years (range, 28-33 yr). The 21 patients reported improvement of the preoperative neurological symptoms. At the last follow-up, the motion was preserved in 19 of the 26 (73%) segments. None of the patients presented with symptomatic adjacent segment degeneration. Nineteen of the 21 (90%) patients presented heterotopic ossification, but none of them underwent reoperation correlated with heterotopic ossification. No device-related adverse events were recorded.. Artificial disk replacement to treat degenerative cervical disk disorders can preserve the motion of the spinal unit in young patients, which fulfills the original purpose of its design. We consider this procedure is worth applying in such a population. However, whether this procedure can prevent adjacent segment degeneration will require further investigation.. 2.

Topics: Adult; Alloys; Cervical Vertebrae; Decompression, Surgical; Equipment Safety; Female; Follow-Up Studies; Humans; Intervertebral Disc Degeneration; Male; Middle Aged; Neck Pain; Ossification, Heterotopic; Postoperative Complications; Radiculopathy; Radiography; Range of Motion, Articular; Reoperation; Retrospective Studies; Severity of Illness Index; Spinal Cord Compression; Surveys and Questionnaires; Total Disc Replacement; Treatment Outcome

Prospective study evaluating the adjacent segment degeneration after lumbar dynamic stabilization using pedicle screws and a Nitinol spring rod system.. To assess the changes of the adjacent and implantation segments after lumbar dynamic stabilization surgery using magnetic resonance imaging (MRI).. Lumbar fusion operations can accelerate the degeneration of adjacent levels. Recently, motion preservation surgery has been attempted for the treatment of lumbar degenerative diseases to prevent degeneration of adjacent levels. However, there is a controversy over whether lumbar dynamic stabilization accelerates degeneration of adjacent levels.. We performed the dynamic stabilization procedure in patients with grade 1 degenerative lumbar spondylolisthesis, lumbar spondylotic stenosis with segmental instability, or a herniated lumbar disc with segmental instability. Postoperative MRI scans were taken for >2 years in all enrolled 25 patients. We compared the findings regarding disc degeneration in the cranial, implantation, and caudal segments between the preoperative period and 2-year-plus postoperative period using T2-weighted sagittal MR images. In addition, we investigated the progression of the central and foraminal stenosis of the adjacent cranial and caudal levels.. Three of the 25 cranial adjacent discs (12.0%) and 4 of the 25 (16%) caudal adjacent discs demonstrated progression of degeneration after dynamic stabilization. One of the 13 discs in the implantation segment demonstrated progression of degeneration, and 2 of the 13 discs in the implantation segment showed improvement of their disc degeneration (disc rehydration). A total of 5 (10.0%) of the 50 segments (3 cranial and 2 caudal adjacent) showed increased spinal stenosis postoperatively. Among the 5 cases, 3 patients had symptomatic adjacent stenosis.. According to our results, lumbar dynamic stabilization using pedicle screws and a Nitinol spring rod system may not prevent adjacent level degeneration completely.

Topics: Aged; Alloys; Bone Screws; Decompression, Surgical; Disease Progression; Diskectomy; Female; Follow-Up Studies; Foraminotomy; Humans; Internal Fixators; Intervertebral Disc Degeneration; Intervertebral Disc Displacement; Joint Instability; Laminectomy; Lumbar Vertebrae; Magnetic Resonance Imaging; Male; Middle Aged; Osteoarthritis; Postoperative Period; Prospective Studies; Spinal Fusion; Spinal Stenosis; Spondylolisthesis; Spondylosis

Anterior cervical discoidectomy with or without fusion is a well established surgical remedy for cervical prolapsed intervertebral disc (PIVD) disease. If fusion is done by an iliac bone graft then internal fixation is commonly used to keep the graft in position. This study was conducted to determine the efficacy and tolerability of shape memory alloys, especially NiTi (nickel titanium) clips in the stabilization of grafts following anterior cervical discoidectomy.. 133 NiTi clips were applied in 119 patients between January 2002 and December 2008. The patients age ranged from 38-60 years. There were 66 male and 53 females. Various indications for fixation of the spine included degenerated cervical spondylosis with single level PIVD (105) and two level PIVD in 14 patients. The cine mode fluoroscopy confirmed the perioperative correct placement of grafts and clips in all the patients. Follow-up ranged from 2 to 8 years (mean: 4.6 years).. Single level discoidectomy was performed in 105 patients and two level disc removal was done in 14 patients. A single NiTi clip was applied in all the cases except for 14 cases of two level PIVD. No procedural complication or adverse reaction to the clip was noted. There was no movement at the operated level in dynamic lateral view X-ray of cervical spine at the 1st postoperative day as well as on follow-up. Graft extrusion was seen in one patient on the 2nd day after surgery and was reoperated. Bony fusion occurred in all patients after 9 - 12 months of surgery. There was no incidence of breakage or dislodgement of the clip from the site where it was inserted. No artifact was noted in cervical MRI done in 33 patients.. NiTi clips are a simple alternative for cervical spine stabilization after discoidectomy. Their insertion is simple, minimally invasive, does not require any special set of instruments and they are much more economical than other established methods of treatment. These clips are accepted well by human tissue and do not interfere with MRI.

Topics: Adult; Alloys; Biomechanical Phenomena; Cervical Vertebrae; Diskectomy; Feasibility Studies; Female; Follow-Up Studies; Humans; Intervertebral Disc Degeneration; Intervertebral Disc Displacement; Longitudinal Studies; Magnetic Resonance Imaging; Male; Middle Aged; Minimally Invasive Surgical Procedures; Retrospective Studies; Sutures; Titanium; Treatment Outcome