bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Prospective Clinical and Morphological Study of Facet Joint Integrity following Implantation of Two Different Cervical Disc Replacements
Authors: Trouillier Hans , Gebhard Harry , Hintermann Beat , Kampe Jan 
Published: May 2015

Introduction The ideal patient for a disc replacement with a mechanical prosthesis, such as Discocerv of Scient̀X or a M6 of spinal kinetics with a soft core, is under 60 years of age with monosegmental, symptomatic degenerative disc disease without degeneration in the facet joints. Following implantation of prosthesis any changes in load through the facet joints appear as changes in bone mineral density at the operative and adjacent levels. A comparing study was designed to investigate whether facet joint sclerosis and degeneration occurs following the implantation of the two different disc types. Materials and Methods In this prospective study, suitability for disc replacement was determined by CT scan and clinical assessments. Patients were followed up 6 and 12 months postoperatively. X-ray and CT-controlled osteoabsorptiometry were used to assess any changes in bone mineral density following implantation of the two different disc models. A 3D reconstruction enabled visualization of the bone density distribution in the facet joints. Pain and function was assessed using standard outcome scores (visual analog scale [VAS] back pain score, Oswestry disability index [ODI], and short form-36 [SF-36]). Mobility was determined by flexion/extension X-rays. Results In total, 20 patients received disc replacement, 10 patients in each group. The postoperative location of the areas of maximum bone mineral density did not change compared with the preoperative condition. There was a reduction in subchondral mineralization density in the facet joints of the operated segments and, to a lesser degree, in the neighboring segments. The mean improvement in the VAS back pain score 6-months postoperatively was 60%. Function, as measured by ODI and SF-36 scores, had improved by up to 70% at the same postoperative time point. Improvements in pain and function scores were maintained 12 month postoperatively. On average, normal movement and weight bearing was observed 8 weeks postoperatively. Mobility increased by a mean of 8 degrees in the operated segment. There was no big difference between the two disc designs. Conclusion Facet joint sclerosis and degeneration did not occur following cervical disc replacement. There was no big change in the location of the areas of maximum density, indicating that mobility approached normal physiological levels. The reductions in subchondral mineralization density suggest normalization away from degenerative sclerosis in both disc types. This did not appear to be due to adoption of postoperative postures as normal movement and weight bearing was achieved. Further study is needed to assess these two different disc designs and the degree to which restoration of segmental mobility leads to the normalization of degenerative sclerosis.
Persistent Axial Neck Pain after Cervical Disc Arthroplasty
Authors: Kang Daniel , Wagner Scott , Lehman Ronald 
Published: May 2015

Introduction There are relatively few, non-industry sponsored studies examining the outcomes and complications of cervical disc arthroplasty (CDA). In addition, there is very little literature examining optimal radiographic parameters for placement of CDA. Therefore, we set out to perform a single-center evaluation of the radiographic outcomes and association with complications following CDA. Methods We performed a retrospective review from August 2008 to August 2012 of all patients from a single military tertiary medical center undergoing cervical disc arthroplasty. Preoperative, immediate postoperative, and final follow-up films were evaluated. The clinical outcomes and complications associated with the procedure were also examined. Results A total of 312 patients were included in the review, with an average radiographic follow-up of 14 months and a 15.1% rate of persistent axial neck pain. For patients with persistent neck pain, the rates of heterotopic ossification (HO) formation and osteolysis were 27.7% and 14.9%, respectively, while the rates were significantly lower for patients without neck pain (12.8% and 6.2%, respectively, p = 0.01). There were no differences in preoperative facet arthrosis, pre- or postoperative disc height, segmental range of motion, or placement of the device relative to the posterior edge of the vertebral body. However, patients with implants more centered between the uncovertebral joints were more likely to experience posterior neck pain ( p =0.03). Conclusions We found that posterior, axial neck pain is relatively frequent after cervical disc arthroplasty, and patients with persistent neck pain were significantly more likely to develop heterotopic ossification or implant-related osteolysis. We also found that patients with implants that were placed off-centered were less likely to also complain of neck pain, though the reasons for this finding are unclear.
Short Link N as a Therapeutic Agent to Treating Early Intervertebral Disc Degeneration
Authors: Algarni Nizar , Epure Laura , Grant Michael , Salem Omar , Antoniou John , Mwale Fackson 
Published: May 2015

Introduction Although the disc has limited endogenous repair activity, induced repair of disc tissue may be possible by the intradiscal injection of growth factors to stimulate the production of disc matrix. We previously demonstrated that Link N (DHLSDNYTLDHDRAIH), a naturally occurring peptide generated by the N-terminal proteolytic fragmentation of link protein during tissue turnover, can act as a growth factor in the disc. It can stimulate matrix production in vitro, in vivo, and in intact ex vivo human intervertebral discs (IVDs). We have recently discovered that AF cells have the ability to proteolytically process Link N resulting in a fragment spanning amino acid residues 1 to 8 (US patent 61870394)—short Link N (sLink N). Our in vitro data indicates that the biologically active sequence is preserved within this fragment and, thus, sLink N could represent a potential stable growth factor able to stimulate disc repair. Separately, we developed a long-term organ culture model with vertebral bone. The purpose of the present study was to evaluate the effect of sLink N and compare its efficacy to Link N in this novel organ culture model of early disc degeneration. Material and Methods Caudal IVDs from the tails of 20 to 24-month old steers were isolated with adjacent vertebral bone. After 7 days of preconditioning in culture, degeneration was induced in IVDs by a single injection of 50 µg trypsin into the NP. After 7 days after induced-degeneration, the trypsin-treated discs were injected with either sLink N or Link N (100 µg/disc, n = 6 discs/group). Four of the trypsin-treated degenerate discs were injected with PBS alone to serve as a control for degeneration while four discs served as nondegeneration controls. At 2, 4, and 8 weeks posttreatment, two discs from each treatment and control groups were processed for biochemical analyses. Proteoglycan (predominantly aggrecan) synthesis in the NP was monitored as sulfated glycosaminoglycan using the 1,9-dimethylmethylene blue dye-binding assay, and Western blotting was performed to determine the expression of aggrecan and type II collagen in the tissue. Results Without intervention, at all-time points, the GAG content in degenerate discs dropped to approximately 50% of that in nondegenerate controls. In contrast, sLink N or Link N, significantly increased the GAG content of the discs compared with the GAG content in degeneration control discs. However, sLink N was more potent at inducing proteoglycan and type II content than Link N. Conclusion The results revealed that sLink N or Link N have the ability to restore tissue content and that sLink N is more potent than Link N in an early state of the disease. These results have implications in relation to using either sLink N or Link N when regenerating a functional NP in the degenerated IVD or in repairing cartilage.
A Comparison of Ocular Radiation Exposure Utilizing Three Types of Leaded Glasses
Authors: Waddell Bradford S. , Waddell Hunter , Zavatsky Joseph M. 
Published: May 2015

Introduction Minimally invasive spine (MIS) surgery has an increased reliance on fluoroscopic X-ray. Compounded radiation exposure to the surgeon has become increasingly concerning and ocular radiation has been associated with cataract formation. Leaded eye protection can reduce ocular radiation exposure. We evaluate the efficacy of three types of leaded eyeglasses during typical views of MIS spinal surgery. Materials and Methods Utilizing anthropomorphic patient and surgeon phantoms, radiation exposure to the lens of the surgeon phantom was measured. Four groups were analyzed: Group 1—no glasses (NO); group 2—lead lens without leaded sides (WOLS); group 3—lead lens with lead sides (WLS); group 4—sport wrap around leaded glasses (sport). A total of 15 individual 20-second exposures in the anteroposterior and lateral X-ray positions with phantom head positions at 0, 45, and 90 degrees were performed. All glasses were 0.75 mm lead equivalent. Radiation dose was measures using a solid-state dosimeter (Unfors EDD-30; Billdal, Sweden). Average radiation dose for each position, total radiation dose, and percent reduction to the lens was calculated for each pair of glasses. Student t-test was used to calculate significance. Results All three glasses (WLS, WOLS, and sport) had significant reductions in ocular radiation versus no glasses at all individual head positions ( p ≤ 1.31 × 10−34). Sport had a significantly lower ocular radiation dose than WLS at all positions except at 90 degrees AP (0.323 vs. 0.334, p = 0.001). Sport also had a significantly lower ocular radiation dose than WOLS in all cases except 0 degrees AP (0.376 vs. 0.285, p = 0.0003) and 90 degrees lateral (0.988 vs. 0.862, p = 7.38 × 10−28). WOLS had a significantly lower radiation dosage at all positions over WLS except at 45 degrees AP (0.286 vs. 0.279, p = 0.303). Average total radiation dosage was 36.47 µgray without glasses, 3.13 µgray for WOLS, 4.134 for WLS, and 3.32 µgray for sport. All glasses resulted in a significant reduction in total radiation dose over no glasses ( p ≤ 8.37 × 10−32). There was no statistical difference in the total radiation dosage of WOLS versus Sport ( p = 0.6) and both Sport and WOLS were significantly lower than WLS ( p = 0.009 and 0.003, respectively). Discussion Our study demonstrates a significant reduction in radiation exposure to the eye with all three types of leaded glasses. This study confirms other reports showing varying degrees of exposure with different angles and X-ray views. Furthermore, we show that contrary to intuition, leaded glasses with lead sides (WLS) may have adverse effects by possibly trapping radiation and increasing ocular radiation exposure. Based on our results, we recommend the use of sport-wrap type leaded glasses or those without lead sides (WOLS).
Patient and Surgeon Exposure to Radiation in Intraoperative CT-Based Spine Navigation
Authors: Mendelsohn Danny , Strelzow Jason , Batke Juliet , Dvorak Marcel , Fisher Charles , Street John , Dea N. 
Published: May 2015

Introduction Intraoperative imaging is critical in spine surgery for determining the spinal level, visualizing alignment, and guiding implant placement. Imaging modalities include plain X-rays, fluoroscopy with C-arm and intraoperative CT scanning (O-arm). These imaging modalities emit ionizing radiation to the surgical team and the patient. The amount of radiation emitted to the patient and the surgeon with intraoperative CT-based spine navigation were compared. The impact of intraoperative CT on the use of intraoperative X-rays and postoperative X-rays and CTs was investigated. Material and Methods An ambispective review of surgical cases using intraoperative CT at Vancouver General Hospital over 1 year was performed. The number of intraoperative X-rays, fluoro and CT dosages were recorded and standardized to effective doses. The number of perioperative imaging investigations was compared with a cohort of surgical cases involving only intraoperative X-rays and fluoroscopy. A literature review was performed to enable a comparison of radiation exposure to historical values for fluoroscopic-guided spine instrumentation. Results A total of 73 surgical cases involving an average of 5.44 levels of instrumentation were reviewed. Thoracic and lumbar spine instrumentations were associated with the highest radiation emission from all modalities compared with cervical and cases (TL: 5.65 mSv vs. C: 2.19 mSv). Major deformity and degenerative cases involved more radiation exposure than trauma and oncology cases (5.81 vs. 3.54 mSv). On average, the patient was exposed to 5.9 times more radiation compared with the surgical team. Patient exposure was three times the values reported in the literature for open thoracolumbar fusions. In comparison, radiation exposure to the surgeon was reduced by 35% compared with conventional fluoroscopically guided open thoracolumbar fusions and 70% less than minimally invasive thoracolumbar fusions. The average radiation total radiation exposure to the patient was 6.05 mSv, a value less than a single lumbar CT scan (7.5–10 mSv). The use of intraoperative CT did not reduce the number of postoperative X-rays or CT scans acquired during the admission or within 1 year following surgery. Conclusion Intraoperative CT increases the radiation exposure to the patient and reduces the radiation exposure to the surgeon when compared with the fluoroscopic-guidance radiation exposure reported in the literature. Thoracolumbar instrumentations for major deformity and degenerative diagnoses are associated with the highest radiation exposure. Although intraoperative CT can improve the accuracy of spine instrumentation, surgeons should be aware of the increased radiation exposure to the patient compared with conventional fluoroscopy-guidance.
Reduction in Fluoroscopy Time, Radiation Dosage, and Complications Using an Innovative Guide Wire for Percutaneous Pedicle Screws
Authors: Briski David C. , Waddell Bradford S. , Cook Brandon W. , Zavatsky Joseph M. 
Published: May 2015

Introduction Despite the benefits of minimally invasive spine surgery (MIS), inherent risks to the patient and surgeon exist. Numerous studies demonstrate increased radiation exposure with MIS secondary to the need for increased fluoroscopy, thereby increasing the risk of cataracts and malignancy. Additionally, inadvertent advancement of standard guide wires through the vertebral body can occur, placing vital ventral structures at risk. This study evaluates the benefit of utilizing a novel split-tip guide wire for percutaneous pedicle screw placement. Methods A total of 30 consecutive cases of MIS transforaminal lumbar interbody fusion (TLIF) at L5–S1 were retrospectively evaluated. Group 1: Standard straight guide wire, 15 patients; group 2: split-tip guide wire, 15 patients. Except for the type of guide wire utilized, the same operative technique was used in each case, including bicortical S1 screw fixation. Total fluoroscopy time, radiation dosage, operative time, and complications were evaluated. Technique: (1) S1 pedicles are cannulated with standard Jamshidi needles. (2) Y-wires are placed through Jamshidi needles. (3) A cannulated Steffee probe cannulates the distal sacral promontory over the Y-wire. (4) The Steffee probe is retracted 50% and Y-wire is repositioned (Y-wire design prevents inadvertent advancement through sacral promontory). (5) The proximal S1 pedicle can be tapped over the Y-wire (not required). (6) Cannulated pedicle screws are placed over the Y-wire, engaging the distal sacral promontory for bicortical S1 purchase. Results Mean total fluoroscopy time per case for group 1 was 231.1 seconds versus 154.2 seconds for group 2 ( p = 0.017). Mean radiation dosage for group 1 was 16.22 versus 8.69 rads in group 2 ( p < 0.001). There was no significant difference in operative time ( p = 0.18). Inadvertent advancement of two S1 guide wires occurred in two different patients in group 1. Postoperative abdominal CT scans with contrast were negative. Conclusion Utilizing a split-tip guide wire for percutaneous pedicle screw placement significantly decreased fluoroscopy time by 33% and radiation dosage by 46%. Cannulating the sacral promontory allows for bicortical S1 screw purchase, but removes the mechanical stop preventing inadvertent guidewire advancement. The split-tip guidewire may prevent wire advancement and decreases the need for fluoroscopic surveillance. This, in turn, reduces the risk of injury to structures ventral to the spine, while reducing the exposure to harmful radiation.
Cervical Spondylotic Myelopathy Treated by Cervical Laminectomy: Prevalence of Pre- and Postoperative Symptoms
Authors: Zaater Ahmed 
Published: May 2015

Introduction This is a retrospective study to find out the prevalence of symptoms before and after cervical laminectomy surgery in a series of patients with cervical spondylotic myelopathy (CSM). Material and Methods A total of 45 patients with CSM (29 males and 16 females; mean age, 54.2 year) treated by laminectomy with or without posterior fixation were included. Cases were followed up for an average of 26 months. The modified Japanese Orthopedic Association (mJOA) score for CSM to evaluate the severity of myelopathy, the prevalence was assessed by the presence or absence of a full mJOA score for each function. The persistence rate (%) of each function impairment is (postoperative prevalence/preoperative prevalence × 100) was also assessed postoperatively. Results The preoperative motor function impairment prevalence was 74.2% in the upper extremities and 78.4% in the lower extremities, whereas the sensory function impairment was 58.2%. The preoperative prevalence of urinary bladder function impairment was 41.2%. The persistence rate of motor function impairment was 51.2% in the upper extremities and 73.5% in the lower extremities, whereas that of sensory function impairment was 74.2%. The urinary bladder function impairment persistence rate was 48.2%. Conclusion The preoperative prevalence of motor function impairment in the upper and lower extremities is higher than that of other function impairments, and impairments in lower extremity motor function and sensory function often persist after surgery.
Outpatient Cervical and Lumbar Spine Surgery is Feasible and Safe
Authors: Helseth Øystein , Lied Bjarne , Helseth Eirik 
Published: May 2015

Introduction There is an increasing demand for surgery of the degenerative spine. Limited health care resources draw attention to the need for cost-effective treatments. Outpatient surgery, when safe and feasible, is more cost-effective than inpatient surgery. The aim of this study is to study types and rates of complications following outpatient lumbar and cervical spinal decompressions. Material and Methods Complications were recorded prospectively in 1449; 1073 lumbar, 376 cervical; outpatients undergoing microsurgical decompression for degenerative spinal disease, at the private Oslofjord Clinic, in the time period 2008 to 2013. Results Surgical mortality was 0%. A total of 49 (3.4%) minor and major complications were recorded in 49 individual patients. Three (0.2%) patients had to be admitted to a hospital the day of surgery. Twenty-two (1.5%) patients were admitted to a hospital within 3 months due to surgery-related events. The encountered complications were postoperative hematoma (0.6%), neurological deterioration (0.3%), deep wound infection (0.8%), dural lesion with CSF-leakage (1.0%), persistent dysphagia (0.1%), persistent hoarseness (0.1%), and severe pain/headache (0.4%). All of the life-threatening hematomas were detected within 6 and 3 hours after cervical and lumbar surgery, respectively. Conclusion This series of 1,449 consecutive outpatient microsurgical spinal decompressions adds to the growing literature in favor of outpatient spinal surgery, in properly selected patients. Approximately 99% of the patients were successfully discharged either to their homes or to a hotel on the day of surgery. The surgical mortality was 0%, the overall complication rate was 3.4, and only 1.5% had to be admitted to a hospital within 3 months after surgery.
Development of a Classification System (OF-Classification) and a Score for Therapeutic Decision-Making (OF-Score) for Osteoporotic Thoracolumbar Fractures
Authors: Schnake Klaus John , Hahn Patrick , Franck Alexander , Blattert Thomas , Zimmermann Volker , Ullrich Bernhard , Gonschorek Oliver , Müller Michael , Katscher Sebastian , Hartmann Frank 
Published: May 2015

Introduction The prevalence of osteoporotic fractures is continuously on the rise. The adequate treatment of the predominantly geriatric patients is quite challenging. Osteoporosis can either be the cause of thoracolumbar fractures (nontraumatic fracture) or act as a contributing factor in traumatic fractures. No commonly accepted classification for osteoporotic fractures currently exists. The goal of the “osteoporotic fracture” working group was to develop a classification system and a score to aid therapeutic decision-making process for patients with osteoporotic thoracolumbar fractures. Material and Methods The development of both the classification and the score followed an established methodological pathway. Extensive literature research followed by in-depth discussions in nine consecutive sessions of expert meetings resulted in the proposed classification and scoring system. Between the sessions the classification and the score were applied by the group members in daily practice. The radiological and clinical data of 707 consecutive patients were subsequently collected in 16 clinics and evaluated. Interobserver reliability was calculated after evaluation of 146 fractures by 6 raters. Results The OF-classification consists of five subgroups: OF 1—no deformation (edema in MRI STIR-sequence); OF 2—deformation without or with only minor involvement of the posterior wall (< 1/5); OF 3—deformation with distinct involvement of the posterior wall (> 1/5); OF 4—loss of vertebral frame structure, vertebral body collapse, or pincer type fracture; OF 5—injuries with distraction or rotation. Interobserver reliability showed substantial agreement (Kappa 0.63). The OF-score contains the following parameters: fracture morphology (OF-classification), bone mineral density, potential sintering of the fracture, pain, neurological deficit, potential mobilization, and general health status of the patient (ASA grading), respectively. According to the OF-score, 29% of patients should have received conservative treatment and 49% surgical treatment, respectively. The final choice of treatment in the participating clinics correlated in 85% of cases with the OF-score. Conclusion The OF-classification consists of five subgroups and shows substantial interobserver reliability. In comparison to other classifications, the OF-classification is easy to use and provides a superior differentiation of the typical osteoporotic fracture morphologies. The OF-score takes the clinical status of the predominantly geriatric patients into account to aid the decision-making process in adequate therapeutic strategies. The generated treatment recommendations reflect the actual treatment strategies of specialized clinical centers.