Global Spine Journal
The laminar closure (LC) is known as an early complication of open-door cervical laminoplasty, and cervical miniplates can be used for preventing LC. Though the relation between the number or the position of the miniplates and LC is unclear. The aim of this study is to evaluate between miniplate setting methods and LC after open-door cervical laminoplasty. Material and Methods: After informed consent, 46 patients who underwent open-door cervical laminoplasty using miniplates, 164 laminas are
... luded in this study (32 men, 14 women; mean age 68.9 years; mean follow-up 9.2 months; 20 with ossification of posterior longitudinal ligament, 20 with cervical spondylosis, 2 with trauma, 2 with cervical radiculopathy, 1 with cervical herniation, and 1 with rheumatoid arthritis). The canal-to-body ratio (CBR) was determined by dividing the anteroposterior diameter of the spinal canal by that of the vertebral body at each lamina on cervical neutral lateral X-ray. LC was defined as a CBR decrease of 10% or more between immediately after the surgery and the final follow-up. We evaluated the LC frequency on each lamina with/without miniplate. The plate density (PD) was defined dividing the number of elevated laminas with miniplate by that of all elevated laminas in a patient, and we defined as group A (PD < 0.5), group B (PD ¼ 0.5), group C (PD>0.5), and evaluated the LC frequency of each group. Results: The mean CBR were 1.02 (0.72-1.45) immediately after the surgery and 0.99 (0.68-1.44) at the final follow-up. LC occurred in 10/46 (21.7%) patients and in 13/ 164 (7.9%) laminas. And the LC frequency of each lamina were C3 1/15 (6.7%), C4 5/43 (11.6%), C5 4/46 (8.7%), C6 3/45 (6.7%), and C7 0/15 (0%). The LC frequency in the elevated lamina were significantly less with miniplate 2/95 (2.1%) than that of without miniplate 11/69 (15.9%; P < .01). The LC frequency of each groups were group A 5/8 (62.5%), group B 2/ 12 (16.7%), and group C 3/26 (11.5%), and group A showed significantly higher LC frequency than that of the other 2 groups (P < .05). Discussion: LC after open-door laminoplasty occurred in 33.3% patients and 44.7% laminas in the previous studies, while 21.7% patients and 2.1% laminas with miniplate in this study. Miniplates are thought to be a reasonable option to prevent LC. The elevated laminas of PD < 0.5 showed significantly higher LC occurrence than that of PD ¼ 0.5 or more. Further studies are needed to establish the best PD to consider cost-effectiveness. Conclusion: The miniplates are reasonable option for preventing LC of open-door cervical laminoplasty, though the plate setting methods should be carefully considered plate density less than 0.5. E-Posters 191S while DCI group was normal. Conclusion: Cervical disc arthroplasty and dynamic cervical implant in treatment of cervical spondylopathy can retain the range of motion, recover, and maintain the height of disc and cervical lordosis. Introduction: Artificial cervical disc replacement (ADR) is a newer treatment option that obtained US FDA approval in 2007 that allows for effective discectomy and neural element decompression while preserving range of motion and potentially decreasing complications of pseudoarthrosis and adjacent segment disease associated with anterior cervical discectomy and fusion (ACDF). A growing body of evidence has demonstrated that ADR is both safe and efficacious with good mid-to longterm outcomes that are noninferior and potentially superior to ACDF. Methods: A retrospective database study was performed within the Humana portion of the PearlDiver Record Database (PearlDiver Inc, Warsaw, IN). Patients undergoing cervical ADR between January 1, 2007, and September 30, 2015, were identified using Current Procedural Terminology (CPT) codes. We collected annual trends, reimbursement costs, and patient demographic information, including sex, age, and inpatient or outpatient status. Patients data were collected from the time of operation to 1 year postoperative. Complications were grouped into 7 categories: pain, mechanical and bonerelated complications including adjacent disc degeneration, nerve injury, dysphagia and dysphonia, infections, adverse reactions (hemorrhage, embolism, fibrosis, stenosis, thrombosis), and revision and reoperation procedures (removal of ADR, conversion to ACDF, revision ADR, and/or cervical osteotomies). Results: A total of 293 patients were identified in the Humana database receiving either single or multilevel ADR between 2009 and 2015. ADRs was most commonly performed in patients aged 40 to -54 years. With regard to complications, fewer than 3.7% of patients (<11) had new onset pain within 1 year after CDR. A total of 12.3% of patients (36) reported a mechanical and/or bone-related complication within 1 year. No patients indicated a new nerve injury within 6 months of follow-up. Fewer than 11 patients (<3.7%) presented with dysphagia or dysphonia within 6 months, infection within 3 months, or a revision or reoperation within 1 year. Due to PearlDiver limitations on privacy, exact numbers could not be obtained for incidence less than 11 patients. Average reimbursement for single-level inpatient ADR was $33 696.28 versus outpatient as $34 675.12 with no statistically significant difference (P ¼ .29). Conclusion: Previously reported rates of complications within 1 year of ADR have been reported between 0% and10% in other large studies. Our study reported bone and mechanical related complications within 1 year of procedure to be consistent as previously reported. Additionally, rates of dysphagia or dysphonia and revision or reoperation were also similar to previously reported studies. Cost data for our study reveal no significant difference between inpatient and outpatient ADR, which has implications for health care payers. We feel that this study provides valuable data regarding inpatient versus outpatient costs and reveals a slightly higher rate of complications within the 1-year period, specifically in the mechanical and bone-related category, than may have been previously reported in the cervical ADR IDE (investigational device exemption) trials. Introduction: The purpose of this study is to present the longterm results and to evaluate the safety and effectiveness of lumbar disk arthroplasty in treatment of patients with symptomatic lumbar degenerative disk disease. Materials and E-Posters 195S Methods: A total of 154 patients were analyzed before surgery, after disk arthroplasty and at 3 months, 6 months, 12 months, 24 months, 36 months, 48 months, and 60 months after total disc replacement. Clinical assessments included the visual analogue scale (VAS), and the Oswestry Disability Index (ODI) scores. Radiographic assessments included lumbar lordosis (LL), intervertebral disc height (IDH), and range of motion (ROM) of the total lumbar spine. Complications at the 5-year follow-up were collected as well. Results: Mean follow-up period was 62.17 months. There was clinical improvement in terms of VAS and ODI from the preoperative to the final follow-up (P < .01). Overall, ROM of the total lumbar spine was maintained during the follow-up. Statistically significant (P < .05) improvements in the trend of IDH and LL were noted at the follow-up. Twenty-four patients were observed an appearance of heterotopic ossification at the 5-year followup, with 18 patients appeared at Class II and 7 patients at Class III. Adjacent segment degeneration assessed by radiographic evidence was found in 4 patients. Conclusion: Lumbar disk replacement showed significant improvement in clinical outcomes at 5 years. It not only effectively preserves the motion of both total lumbar spine and operated segments, but also restores normal IDH and LL up to 5 years postoperation. 196S Global Spine Journal 9(2S) and entered into Microsoft Excel. In Excel, data were then cleaned, categorized, and transferred to SPSS version 21 for analysis. Results from the analysis were summarized as means, standard deviations, and presented in line and bar graphs. Results: One hundred CT scans were used for the study with 49 males and 51 females, with an age range of 18 to 63 years. On CT scan, pedicle width mean measurements were L1-7.2 mm, L2-7.6 mm, L3-9.2 mm, L4-10.8 mm, and L5-14. 6 mm. The mean angle of insertion on CT scan was L1 19.7 , L2 20.5 , L3 22 , L4 24.1 , and L5 29.8 , and pedicle chord length was L1 48.6 mm, L2 49.9 mm, L3 50.1 mm, L4 49.8 mm, and L5 50.1 mm. Conclusion: The pedicle width on CT scan measurements increased from 7.2 mm to 14.6 mm between L1 to L5. The angulation increased from L1 to L5 on CT scan measurements from 19.7 at L1 to 29.8 at L5. The chord length range measurement on CT scan was from 48.6 mm to 50.1 mm. Recommendations: The minimum size of screw diameter that should be used is 6.5 mm with a length of 45 mm angulated between 20 and 30 from L1 to L5. Based on the variation, there is need for measurements of the pedicle dimensions before transpedicular instrumentation. Further research should be carried out on lumbar pedicle dimensions based on age, weight, and height to assess whether their exists variations.