Single-level Fusion Research Articles

Learning curve analysis of 3D-fluoroscopy image-guided pedicle screw insertions in lumbar single-level fusion procedures.

The implementation of 3D-navigation in the operating theater is reported to be complex, time consuming, and radiation intense. This prospective single-center cohort study was performed to objectify these assumptions by determining navigation-related learning curves in lumbar single-level posterior fusion procedures using 3D-fluoroscopy for real-time image-guided pedicle screw (PS) insertions. From August 2011 through July 2016, a total of 320 navigated PSs were inserted during 80 lumbar single-level posterior fusion procedures by a single surgeon without any prior experience in image-guided surgery. PS misplacements, navigation-related pre- and intraoperative time demand, and procedural 3D-radiation dose (dose-length-product, DLP) were prospectively recorded and congregated in 16 subgroups of five consecutive procedures to evaluate improving PS insertion accuracy, decreasing navigation-related time demand, and reduction of 3D-radiation dose. After PS insertion and intraoperative O-arm control scanning, 11 PS modifications were performed sporadically without showing "learning curve dependencies" (PS insertion accuracies in subgroups 96.6 ± 6.3%). Average navigation-related pre-surgical time from patient positioning on the operating table to skin incision decreased from 61 ± 6min (subgroup 1) to 28 ± 2min (subgroup 16, p < 0.00001). Average 3D-radiation dose per surgery declined from 919 ± 225mGycm (subgroup 1) to 66 ± 4mGycm (subgroup 16, p < 0.0001). In newly inaugurated O-arm based image-guidance, lumbar PS insertions can be performed at constantly high accuracy, even without prior experience in navigated techniques. Navigation-related time demand decreases considerably due to accelerating workflow preceding skin incision. Procedural 3D-radiation dose is reducible to a fraction (13.2%) of a lumbar diagnostic non-contrast-enhanced computed tomography scan's radiation dose.

Hypothyroidism increases 90-day postoperative complications in patients undergoing primary single level anterior cervical disectomy and fusion: a matched control analysis.

Anterior cervical discectomy and fusion (ACDF) is indicated for patients suffering from cervical radiculopathy, myelopathy, and degenerative disc disease, among other diseases. There is paucity in the literature regarding postoperative complications in patients undergoing primary ACDF with a diagnosis of hypothyroidism. The purpose of this study is to compare 90-day postoperative complications in patients with and without hypothyroidism undergoing primary ACDF. A retrospective analysis was completed using a national administrative database known as Pearl Diver (Pearl Diver Technologies, Fort Wayne, Indiana) using the International Classification of Disease, ninth revision (ICD-9) codes. The study group consisted of patients having undergone ACDF with an active diagnosis of hypothyroidism 90 days prior to and on the day of surgery. Patients undergoing primary ACDF without hypothyroidism served as the control group. Patients in both groups were randomly matched according to age, gender, and Charlson-Comorbidity Index (CCI). The 90-day postoperative medical complications were assessed along with readmission rates and total cost of care. There were a total of 107,066 patients equally divided between the 2 cohorts. Patients with hypothyroidism had greater odds of developing complications such as non-healing surgical wound (OR: 2.27; P<0.001), pulmonary embolus (OR: 2.16; P<0.001), myocardial infarction (OR: 2.10; P<0.001), compared to patients in the control group after undergoing primary ACDF. Readmission rates were also higher in patients with hypothyroidism (OR: 1.45; P<0.001). Total cost of care was also greater in patients with hypothyroidism compared to patients without hypothyroidism undergoing primary ACDF. Hypothyroidism is a risk factor for worse postoperative outcomes in patients undergoing primary ACDF. Appropriate preoperative optimization with thyroid hormone supplementation could potentially minimize the incidence of developing numerous medical complications, in addition to potentially lowering readmission rates and the total cost of care.

Does Cervical Plate Add Value in Single or Double Level Anterior Cervical Discectomy and Fusion?

Background Data: Optimal surgical approach for anterior cervical discectomy and fusion (ACDF) is still controversial. Some authors believe that addition of locking plate (ACDFP) has higher costs and longer operative time. Other surgeons believe that ACDFP have better clinical outcomes and more sound fusion. The debate is higher in single and doublelevel ACDF.Purpose: To compare the clinical and radiological outcomes in patients with single or double level cervical disc herniation operated by ACDF versus those operated by ACDFP. Study Design: A retrospective, descriptive controlled, non-randomized, clinical case study. Patients and Methods: Forty patients underwent ACDF. They were divided into twogroups; ACDF group and ACDFP fixation group. Each group included 20 patients. They were operated between 2010 and 2017. Participants were evaluated pre-operatively and post-operatively 1, 3, 6, 9 and 12 months after surgery. Operative time, hospital stay and complications were assessed. Pain was scored by a VAS for both upper arm and cervicalpain. The clinical outcomes were compared using Odom’s criteria. Cervical fusion was assessed radiologically. Results: The demographic data of the two groups of patients were fairly homogeneous and comparable. ACDFP group showed slightly better clinical outcome parameters in comparison to ACDF group including VAS for cervical pain (9±5 versus 28±11) and Odom’s criteria scores (15 excellent outcome versus 10). Also ACDFP group showed slightly better radiological fusion rate (100%) in comparison to (85%) in ACDF group. Reported nonunion was higher in ACDF group (15%) in comparison to ACDFP group (0%). Conclusion: Our data suggest that the addition of cervical plate fixation to ACDF mightleads to better clinical outcome and radiological fusion in single and double cervical disc disease. (2018ESJ155)

Effectiveness and Safety of Batroxobin, Tranexamic Acid and a Combination in Reduction of Blood Loss in Lumbar Spinal Fusion Surgery.

A prospective randomized double blind placebo controlled trail. To evaluate and compare the efficacy and safety of batroxobin (botropase), tranexamic acid (TXA), and their combination in reduction of perioperative blood loss in lumbar spine single level fusion surgeries. Spinal surgeries are associated with significant blood loss leading to perioperative anemia and increased need for allogenic transfusion. TXA competitively inhibits plasmin and batroxobin converts fibrinogen to fibrin and theoretically their combination is synergistic. Though TXA is widely studied in controlling blood loss, there is little information on use of batroxobin and their combination. Thus, we aimed to study effect and safety of individual drugs and their combination in controlling blood loss in spinal surgery. Hundred patients were randomized into four groups. Group B received batroxobin, group T received TXA, group BT received batroxobin and TXA and group P received placebo. Outcomes assessed are intraoperative and postoperative blood loss, hematocrit, allogenic blood transfusion, and deep vein thrombosis (DVT), postoperatively. Mean intraoperative blood loss in Group B, T, BT, and P were 268.32 ± 62.92 mL, 340.72 ± 182.75 mL, 256.96 ± 82.64 mL, and 448.44 ± 205.86 mL, respectively. Postoperative surgical site drain collection in Group B, T, BT, and P were 218.00 ± 100.54 mL, 260.40 ± 100.85 mL, 191.00 ± 87.84 mL, and 320.00 ± 125.83 mL, respectively. Intraoperative blood loss of Group P was statistically higher than Groups B and BT (P < 0.001). Mean postoperative surgical site drain collection was statistically significant (P < 0.001). No statistically significant differences in fluid administration (P = 0.751), blood transfusion (P = 1.000), preoperative and postoperative hemoglobin (P = 0.090, P = 0.134, respectively), and deep vein thrombosis (P = 1.000). Batroxobin and combination of batroxobin with tranexamic acid significantly reduced perioperative blood loss when compared with placebo. 2.

Effect of teriparatide (PTH 1–34) on fusion mass and clinical outcomes the year after single-level instrumented posterolateral fusion

BACKGROUND CONTEXT: Successful spine fusion requires formation and remodeling of new bone. For this reason, osteoporosis is a risk factor that affects fusion in spine surgery. Parathyroid Hormone (PTH) is an anabolic drug that increases activity of osteoblasts and osteoclasts. Some studies have demonstrate the PTH accelerates the lumbar posterolateral fusion in osteoportic patients, but the clinical and functional impact of these medication is not well known PURPOSE: To study the influence of the treatment with Teriparatide in the fusion mass and clinical outcome in a group of patients with osteoporosis and a lumbar posterolateral fusion during a 1-year follow-up. METHODS: Seventy-two patients underwent a L4-L5 instrumental posterolateral fusion using pedicle screws and bone graft. Patients were divided into 2 groups: Treated with teriparatide (20µg/day, post-surgery, during 1 year) n= 47, or not treated n=25. Patients were studied before surgery and 3 months, 6 months and 1 year after surgery. The following assessments were performed: quality of bone fusion mass and clinical outcome evaluated by visual analogue scale score (VAS) and Oswestry Disability Index (ODI). RESULTS: Radiographically, a decrease on the volume of fusion mass is observed in all cases, but this decrease was significantly lower in the group of patients treated with PTH. All patients have a significant improvement in pain and function. No differences in the improvement were observed between both groups. CONCLUSIONS: A decrease on fusion mass volume was observed in all cases, but patients on Teriparatide treatment had a better fusion mass volume development. However, these radiological differences did not influence on clinical outcome at 1 year follow-up, as both groups present the same improvement.

Anterolateral Approach for Unstable Lumbar Burst Fracture with Anterior Compression

Background: Lumbar burst fractures are common spinal injuries that cause severe instability with kyphotic deformities and neurological complications requiring surgical decompression and reconstruction with spinal instrumentation for unstable burst fracture, but there is controversy about the optimal surgical approach anterior, posterior or combined approach. Objectives: To assess the efficacy & safety of anterolateral approach in decompression and reconstruction with spinal instrumentation for lumbar burst fractures. Subjects & Methods: A retrospective study including 16 patients, 10 males and 6 females with lumbar burst fractures and anterior compression treated operatively by anterolateral approach for corpectomy and single level fusion by using expandable cage or mesh cage loaded with bone graft and plat with screws. The clinical and radiological follow up after discharge from the hospital ranged from 12 to 24 months. Results: All patients improved regarding the Frankel score more than one grade after surgery, except 2 cases of grade A didn’t improve. Mean preoperative visual analogue scale was 7.4 improving to 0.9 postoperatively. The mean Local kyphosis improved from 8.8° before surgery to -1° after surgery. Conclusions: Anterolateral approach is feasible, effective, and safe approach for unstable lumbar burst fractures. Angular deformity is successfully corrected when the anterior approach is used.

Single oblique cage posterior lumbar interbody fusion with local bone graft as an alternative to double straight-ahead cages posterior lumbar interbody fusion with iliac crest graft

Background Posterior lumbar interbody fusion (PLIF) is a fusion technique with reliable and rapid fusion results. The traditional technique describes the use of two cages filled with bone graft and inserted in a straight-ahead direction within the prepared disc space. Bone graft used is usually harvested from the posterior iliac crest. This study evaluates the use of a single cage inserted diagonally through unilateral discectomy and filled with bone fragments obtained from the local decompression procedure. Patients and methods Fourteen patients underwent pedicle screw-rod supplemented PLIF and spinal canal decompression for symptomatic spinal canal stenosis, instability, or spondylolisthesis refractive to conservative treatment. PLIF was performed using a single PEEK cage filled with impacted graft from the locally excised bone. The PEEK cage was inserted into the prepared intervertebral disc space in an oblique (diagonal) manner to obtain near-symmetrical end-plate loading across the midline. Results The mean follow-up period was 15 months. The mean duration of surgery was 170 and 225 min for single-level and double-level fusions, respectively. The mean volume of blood loss was 850 and 1050 ml for single-level and double-level fusions, respectively. The mean duration for hospital stay was 5 days. Postoperative radiographs showed a mean increase in the disc height by 24.4% and a mean increase in lordosis angle by 4.3°. Pain and functional scores showed marked improvement. The mean Visual Analog Scale decreased from 7.8 to 2.2. The mean Oswestry Disability Index decreased from 82 to 28. The mean Economic Prolo Scale was 3.2 whereas the Functional Prolo Scale was 3.8. Interbody fusion was assessed using lateral radiographs. Loss of demarcation of the bony end-plates with consolidation of graft through the cage was the indication of successful fusion. At final follow-up, 10 patients showed solid fusion, three patients showed delayed fusion, and one patient showed loss of reduction of spondylolisthesis after a traumatic incident and required a revision surgery. Yet, patients with delayed union did show similar improvement to those with early union on the Visual Analog Scale and Oswestry Disability Index. Conclusion The use of single unilateral and obliquely inserted PEEK cage is an effective safe procedure for interbody fusion that gives comparable results to the traditional double-cage technique while shortens the operative time, lowers the blood volume loss, and also lowers the cost for implants used without endangering reliability of the technique.

Changes in Sagittal Alignment After Cervical Disc Arthroplasty: Results of 24 Month Pilot Study

Background Context: For cervical disc replacements to be comparable to the gold standard of cervical discectomy and fusion (ACDF), disc replacements they must be able to provide normal range of motion as well as predictable and reliable correction of cervical alignment. The Synergy Disc was designed to provide correction of alignment in the sagittal plane while restoring physiologic range of motion. Purpose: This study evaluated whether the Synergy Disc provided preservation and/or restoration of sagittal alignment while normalizing kinematics and providing acceptable clinical outcomes. The alignment provided by the Synergy Disc was compared with a retrospective cohort of 30 single- level ACDF patients. Study Design/Setting: The pilot trial was a multi-center, prospective, consecutive patient enrollment study using the Synergy Disc for the treatment of single and two-level degenerative disc disease of the cervical spine. Patient Sample: The procedure was performed on 43 patients (45 implants) with follow-up on 40 patients (42 implants). For the historical cohort ACDF arm, 30 patients with similar follow-up with single level anterior discectomy, fusion and plating were used for segmental lordosis measurements. Outcome Measures: For the Synergy Disc group, the kinematic outcome parameters included: range of motion (ROM), shell angle (SA), disc height (DH), sagittal plane translation and center of rotation (COR) in the X and Y direction. Standard assessments of clinical outcomes were also measured (Neck Disability Index, Visual Analog Scale). For the fusion arm, only functional spinal unit (FSU) angle was recorded using a single preoperative and postoperative standing lateral cervical radiograph. Methods: In the Synergy Disc group, static and dynamic radiological assessments were performed in 43 consecutive patients prior to the placement of the Synergy Disc. Forty patients were studied for the course of the study protocol (3 patients lost to follow-up). For the Synergy Disc group, lateral cervical radiographs were evaluated for range of motion, translation, center of rotation, disc height and shell angle before and at the longest postoperativr follow-up. Neck Disability Index and Visual Analog Scale for arm and neck pain were collected and analyzed. For the fusion group, standing lateral radiographs were reviewed. Results: In all the patients (40 patients, 42 implants), followed up for at least 24 months at an average of 28 months the average SA of the Synergy Disc was maintained at 6±2.7° of lordosis. Preoperative ROM, translation and center of rotation on X axis did not change significantly following surgery. There was a significant upward shift in the center of rotation on Y axis. There was significant improvement in all clinical outcome measures. In the fusion group, with a similar follow-up period, there was a 4° increase in lordosis at the FSU. Conclusions: The Synergy Disc provided lordosis at the surgical level, while maintaining preoperative range of motion, translation and COR X. The lordosis of 6±2.7° provided by the Synergy Disc at 2 years following surgery was comparable to the lordotic correction provided by an anterior cervical discectomy with interbody fusion and plating.

Clinical Outcomes of Single-Level Anterior Cervical Discectomy and Fusion.

The purpose of the present study was to determine the differences in health outcomes between patients with cervical spondylosis who underwent single-level anterior cervical discectomy and fusion (ACDF) and patients with cervical spondylosis who did not undergo an ACDF fusion (non-ACDF). The hypothesis of the study was that patients undergoing single-level fusion have a lower risk of downstream cardiovascular disease and depression. The Medicare 5% sample was used to identify patients who received a diagnosis of spondylosis during 2005-2012. All spondylosis patients were separated into nonoperative and operative groups. Differences in new disease diagnoses, age, sex, and Charlson Comorbidity Index (CCI) scores were recorded. The relative risk (RR) of heart failure was lower in the ACDF group after 3 years (RR = 0.6719; P < .05), 5 years (RR = 0.8477; P = 1.17), and 7 years (RR = 0.7709; P = 1.625). The RR of depression was higher in the ACDF group at 1 year (RR = 2.5008), 3 years (RR = 1.4473), 5 years (RR = 2.2625), and 7 years (RR = 2.2257; P < .05 for all). Mean CCI score of patients before undergoing ACDF was 10 (SD, 9.20), whereas the mean score after surgery was 8 (SD, 7.84; P < .05), and the score for non-ACDF patients remained unchanged at a CCI of 10 (SD, 9.00; P < .05). The results demonstrate the patients in the ACDF cohort have an increased RR of depression but a decreased risk of cardiovascular disease. Further research may be needed to delineate why the ACDF procedure potentially benefits a patient for heart disease but may stress a patient's social/economic supports during the recovery process, thus leading to higher depression rates for patients undergoing ACDF.

Prevalence and Complications of Postoperative Transfusion for Cervical Fusion Procedures in Spine Surgery: An Analysis of 11,588 Patients from the American College of Surgeons National Surgical Quality Improvement Program Database.

Study DesignRetrospective cohort study.PurposeThe purpose of this study was to assess the rate of blood transfusion after cervical fusion surgery, and its effect on complication rates.Overview of LiteratureCervical spine fusions have gained interest in the literature since these procedures are now ever more frequently being performed in an outpatient setting with few complications.MethodsThe American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was used to identify patients that underwent cervical fusion from 2010 to 2013. Multivariate regression analysis was used to determine postoperative complications associated with transfusion and cervical fusion.ResultsWe identified 11,588 patients who had cervical fusion between 2010 and 2013. The rate of blood transfusion following cervical fusion found to be 1.47%. All transfused patients were found to have increased risk of venous thromboembolism (TBE) (odds ratio [OR], 3.19; 95% confidence interval [95% CI], 1.16–8.77), myocardial infarction (MI) (OR, 9.12; 95% CI, 2.53–32.8), increased length of stay (LOS) (OR, 28.03; 95% CI, 14.28–55.01) and mortality (OR, 4.14; 95% CI, 1.44–11.93). Single level fusion had increased risk of TBE (OR, 3.37; 95% CI, 1.01–11.33), MI (OR, 10.5; 95% CI, 1.88–59.89), and LOS (OR, 14.79; 95% CI, 8.2–26.67). Multilevel fusion had increased risk of TBE (OR, 5.64; 95% CI, 1.15–27.6), surgical site infection (OR, 16.29; 95% CI, 3.34–79.49), MI (OR, 10.84; 95% CI, 2.01–58.55), LOS (OR, 26.56; 95% CI, 11.8–59.78), and mortality (OR, 10.24; 95% CI, 2.45–42.71). Patients who had anterior cervical discectomy and fusion surgery and received a transfusion had an increased risk of TBE (OR, 4.87; 95% CI, 1.04–22.82), surgical site infection (OR, 9.73; 95% CI, 2.14–44.1), MI (OR, 9.88; 95% CI, 1.87–52.2), increased LOS of more than 2 days (OR, 28.34; 95% CI, 13.79–58.21) and increase in mortality (OR, 6.3; 95% CI, 1.76–22.48). While, transfused patients who had posterior fusion surgery had increased risk of MI (OR, 10.45; 95% CI, 1.42–77.12) and increased LOS of more than 6 days (OR, 4.42; 95% CI, 2.68–7.29).ConclusionsOur results demonstrate that although cervical fusions can be done as outpatient procedures special precautions and investigations should be done for patients who receive transfusion after cervical fusion. These patients are demonstrated to have higher rate of MI, TBE, wound infection and mortality when compared to those who do not receive transfusion.

Lumbar computed tomography scans are not appropriate surrogates for bone mineral density scans in primary adult spinal deformity.

OBJECTIVE The authors examined the correlation between lumbar spine CT Hounsfield unit (HU) measurements and bone mineral density measurements in an adult spinal deformity (ASD) population. METHODS Patients with ASD were identified in the records of a single institution. Lumbar CT scans were reviewed, and the mean HU measurements from L1-4 were recorded. Bone mineral density (BMD) was assessed using femoral neck and lumbar spine dual-energy x-ray absorptiometry (DEXA). The number of patients who met criteria for osteoporosis was determined for each imaging modality. RESULTS Forty-eight patients underwent both preoperative DEXA and CT scanning. Forty-three patients were female and 5 were male. Forty-seven patients were Caucasian and one was African American. The mean age of the patients was 62.1 years. Femoral neck DEXA was more likely to identify osteopenia (n = 26) than lumbar spine DEXA (n = 8) or lumbar CT HU measurements (n = 6) (p < 0.001). There was a low-moderate correlation between lumbar spine CT and lumbar spine DEXA (r = 0.463, p < 0.001), and there was poor correlation between lumbar spine CT and femoral neck DEXA (r = 0.303, p = 0.036). CONCLUSIONS Despite the opportunistic utility of lumbar spine CT HU measurements in identifying osteoporosis in patients undergoing single-level fusion, these measurements were not useful in this cohort of ASD patients. The correlation between femoral neck DEXA and HU measurements was poor. DEXA assessment of BMD in ASD patients is essential to optimize the care of these complicated cases.

Surgical Outcomes After Segmental Limited Surgery for Adjacent Segment Disease: The Consequences of Makeshift Surgery.

To minimize surgical morbidity, surgeons may opt to perform segmental limited surgery instead of fusion extension for adjacent segment disease (ASD) after lumbar fusion surgery. This study evaluated clinical outcomes from segmental limited surgery without fusion extension for ASD and assessed which clinical factors were associated with reoperation after segmental limited surgery. Medical data of 50 patients who underwent segmental limited surgery for ASD after lumbar fusion surgery between 2005 and 2015 were reviewed. Demographic data, ASD type, preoperative disc and facet degeneration, ASD location, and surgical summary were collected. The primary outcome was reoperation rate at 24 months after surgery. Of patients, 28 (56%) experienced recurrent radiculopathy (visual analog scale score ≥4). Revision surgery was performed in 22 patients (44%). Reoperation was performed more frequently in multilevel fusion first-surgery cases (15/23; 65.2%) than single-level fusion first-surgery cases (7/27; 25.9%; P= 0.005). The lowermost mobile segment group had a lower reoperation-free survival rate than the other group (hazard ratio= 9.85, 95% confidence interval 1.32-73.54, P= 0.01 [log-rank]). The 2-year reoperation-free survival rate for the lowermost mobile segment group was 31.5%, whereas the rate for the other group was 83.3%. Segmental limited surgery as a treatment for ASD after lumbar fusion surgery is likely to fail frequently and result in a high rate of recurrent radiculopathy and revision surgery. Fusion extension surgery is especially recommended for ASD at the lowermost mobile segment owing to the high failure rate.

Stand-alone anterior lumbar interbody fusion – complications and perioperative results

ObjectivesHistorically, anterior lumbar interbody fusion (ALIF) was related to high rates of intraoperative complications and adverse events related to interbody devices. In recent decades, there have been technical adjustments, and cages that are more suitable have emerged. The aim of this study is to evaluate the efficacy and complication rate of the use of stand-alone mini-ALIF using a self-locking cage. MethodsRetrospective single center study. Inclusion criteria: retroperitoneal mini-ALIF for single-level fusion (L5S1); self-locking cage; DDD/stenosis and grade I spondylolisthesis. Exclusion criteria: posterior supplementation, previous fusion/arthroplasty. Endpoints: surgery data, intraoperative and perioperative adverse events related both to surgical access and to the intersomatic device. ResultsEighty-seven cases were enrolled. Median surgical time was 90min; median blood loss was 100mL. The median length of stay in the ICU was zero days; median hospital stay was one day. Ten cases had an adverse event (11.5%): four major adverse events (4.6%; 3L bleeding; DVT; retroperitoneal haematoma; incisional hernia), and seven minor events (8%; peritoneum injury; minor vascular injury; events related to the cage). No cases of retrograde ejaculation were observed. There was improvement in pain, physical restriction, and quality of life (p<0.001). ConclusionsThe mini-ALIF procedure performed for single-level fusion at the distal lumbar level demonstrated low adverse event rates related to both the surgical approach and to the intersomatic device, with reduced hospital stay and satisfactory perioperative clinical results.

324 Lumbar Interbody Fusion Status does not Correlate with Patient Reported Outcomes

Abstract INTRODUCTION Circumferential lumbar arthrodesis leads to high fusion rates for degenerative lumbar spine. Interspinous posterior fixation pedicle screw fixation as an adjunct to interbody graft led to similar fusion rates and patient reported scores in prospective randomized multi-center study. Although commonly used as surrogates of each other it remains unclear whether the fusion scores correlate with patient reported outcomes. METHODS Data was collected as part of a prospective multi-center (11 investigators) study of 101 patients receiving single-level antero-lateral lumbar interbody fusion with supplemental interspinous process fixation (ISPF) or pedicle screw fixation (PSF) for the treatment of degenerative disc disease and/or spondylolisthesis. Subjects were randomized 2:1, ISPF to PSF, for posterior fixation. Patients were followed up to 24 months post-op. Patient reported outcome indices (ODI, SF-36) were collected at each follow-up time point. Lumbar x-ray radiographs were taken at 12 and 24 months. Interbody fusion was scored by an independent radiologist using the Brantigan-Stefee Fraser (BSF) criteria (BSF-1: pseudarthrosis; BSF-2: radiographic locked pseudarthrosis; BSF-3: radiographic fusion). A logistic regression model was used to determine whether a relationship existed between quality of fusion (BSF-3 vs. BSF-1&amp;2) and clinical index improvement at 12 and 24 months. RESULTS &gt;Change in ODI score at 12 and 24 months was not significantly associated with BSF score (P = 0.78 and P = 0.64, respectively). At 12 months,, BSF-3 patients had on average 1.4 greater reduction in ODI compared to BSF-1&amp;2 (95% CI: -8.61, 11.41). Changes in SF-36 score were not significantly associated with BSF score (P = 0.63 and P = 0.18, respectively). For SF-36 Mental, BSF-3 patients had a 2.21 greater increase compared to BSF-1&amp;2 (95% CI: -6.7, 11.13). Instead in SF-36 Physical, BSF-3 patients had a 4.14 lesser increase compared to BSF-1&amp;2 (95% CI: -10.15, 1.88) CONCLUSION Radiological lumbar interbody fusion grading using BSF scale do not correlate with patient reported outcome.

Fully endoscopic lumbar interbody fusion using a percutaneous unilateral biportal endoscopic technique: technical note and preliminary clinical results.

OBJECTIVE Minimally invasive spine surgery can minimize damage to normal anatomical structures. Recently, fully endoscopic spine surgeries have been attempted for lumbar fusion surgery. In this study, the authors performed a percutaneous unilateral biportal endoscopic (UBE) technique as a minimally invasive surgery for lumbar fusion. The purpose of this study is to present the UBE technique of fully endoscopic lumbar interbody fusion (LIF) and to analyze the clinical results. METHODS Patients who were to undergo single-level fusion surgery from L3-4 to L5-S1 were enrolled. Two channels (endoscopic portal and working portal) were used for endoscopic lumbar fusion surgery. All patients underwent follow-up for more than 12 months. Demographic characteristics, diagnosis, operative time, and estimated blood loss were evaluated. MRI was performed on postoperative Day 2. Clinical evaluations (visual analog scale [VAS] for the leg and Oswestry Disability Index [ODI] scores) were performed preoperatively and during the follow-up period. RESULTS A total of 69 patients (24 men and 45 women) were enrolled in this study. The mean follow-up period was 13.5 months. Postoperative MRI revealed optimal direct neural decompression after fully endoscopic fusion surgery. VAS and ODI scores significantly improved after the surgery. There was no postoperative neurological deterioration. CONCLUSIONS Fully endoscopic LIF using the UBE technique may represent an alternative minimally invasive LIF surgery for the treatment of degenerative lumbar disease. Long-term follow-up and larger clinical studies are needed to validate the clinical and radiological results of this surgery.

Use of Allogenic Mesenchymal Cellular Bone Matrix in Anterior and Posterior Cervical Spinal Fusion: A Case Series of 21 Patients.

Study DesignRetrospective case series.PurposeTo report our early experience using allogenic mesenchymal cellular bone matrix (CBM) products in cervical spine fusion.Overview of LiteratureMulti-level cervical fusions have historically yielded lower fusion rates than single level fusions, especially in patients with high risk medical comorbidities. At this time, significant literature in cervical fusion outcomes with this cellular allograft technology is lacking.MethodsTwenty-one patients underwent either multilevel (3 or 4 level) anterior cervical discectomy and fusion, anterior cervical corpectomy and fusion, or posterior cervical fusion. ViviGen (DePuy Synthes Spine, Raynham, MA, USA), an allogenic bone matrix product, was used in addition to standard instrumentation. Radiographic evaluation was performed at 2 weeks, 12 weeks, 24 weeks and 1 year postoperative. Visual analog scale (VAS) and neck disability index (NDI) scores along with return to work and leisure activity were recorded.ResultsAt 6 months postoperative, all patients had radiographic evidence of bone fusion regardless of age or medical comorbidities. All patients reported subjective improvement with a mean decrease in VAS from 8.3 to 1.5 and a mean decrease in NDI from 40.3% to 6.0% at 1 year. All patients also returned to work and/or regular leisure activity within 3 months.ConclusionsTwenty-one patients undergoing high-risk anterior and posterior cervical spine fusion, with the use of a commercially available mesenchymal CBM product, went on to radiographic fusion and all had improvement in subjective outcomes. While further effort and research is needed to validate its widespread use, this study shows favorable use of CBM in cervical fusion for high-risk cases.

Locking stand-alone cages versus anterior plate constructs in single-level fusion for degenerative cervical disease: a systematic review and meta-analysis.

To conduct a meta-analysis to compare the clinical and radiological outcomes in single-level anterior cervical discectomy and fusion (ACDF) surgery for degenerative cervical disease performed by either single-level locking stand-alone cage (LSC) or anterior plate construct (APC). We performed a comprehensive database search of Medline, PubMed, EMBASE and Cochrane Database of Systematic Reviews according to PRISMA guidelines and identified six articles that satisfied our inclusion criteria. We excluded all non-English language articles and articles which did not directly compare LSC and APC. Only papers which focussed on single-level ACDF were included in the study. There were no significant differences in blood loss, clinical outcomes (JOA, VAS, NDI scores) or radiological outcomes (cervical lordosis, segmental Cobb angle, subsidence and fusion) between the two groups. Operative time was significantly shorter in the LSC group (MD 7.2min, 95% CI 0.3-14.1, p=0.04). APC was associated with a statistically significant increase in dysphagia in the follow-up period (OR 6.2, 95% CI 1.0-36.6, p=0.05). LSC and APC have similar clinical and radiological outcomes. Further blinded randomised trials are required to establish conclusive evidence in favour of LSC with regards to minimising post-operative dysphagia. We also encourage future studies to make use of formalised dysphagia outcome measures in reporting complications.

Return to Work and Multilevel Versus Single-Level Cervical Fusion for Radiculopathy in a Workers' Compensation Setting.

Retrospective comparative cohort study. Examine the impact of multilevel fusion on return to work (RTW) status and compare RTW status after multi- versus single-level cervical fusion for patients with work-related injury. Patients with work-related injuries in the workers' compensation systems have less favorable surgical outcomes. Cervical fusion provides a greater than 90% likelihood of relieving radiculopathy and stabilizing or improving myelopathy. However, more levels fused at index surgery are reportedly associated with poorer surgical outcomes than single-level fusion. Data was collected from the Ohio Bureau of Workers' Compensation (BWC) between 1993 and 2011. The study population included patients who underwent cervical fusion for radiculopathy. Two groups were constructed (multilevel fusion [MLF] vs. single-level fusion [SLF]). Outcomes measures evaluated were: RTW criteria, RTW <1year, reoperation, surgical complication, disability, and legal litigation after surgery. After accounting for a number of independent variables in the regression model, multilevel fusion was a negative predictor of successful RTW status within 3-year follow-up after surgery (OR = 0.82, 95% CI: 0.70-0.95, P <0.05).RTW criteria were met 62.9% of SLF group compared with 54.8% of MLF group. The odds of having a stable RTW for MLF patients were 0.71% compared with the SLF patients (95% CI: 0.61-0.83; P: 0.0001).At 1 year after surgery, RTW rate was 53.1% for the SLF group compared with 43.7% for the MLF group. The odds of RTW within 1 year after surgery for the MLF group were 0.69% compared with SLF patients (95% CI: 0.59-0.80; P: 0.0001).Higher rate of disability after surgery was observed in the MLF group compared with the SLF group (P: 0.0001) CONCLUSION.: Multilevel cervical fusion for radiculopathy was associated with poor return to work profile after surgery. Multilevel cervical fusion was associated with lower RTW rates, less likelihood of achieving stable return to work, and higher rate of disability after surgery. 3.

Comparison of volume control and pressure control ventilation in patients undergoing single level anterior cervical discectomy and fusion surgery.

Background and Aims:Pressure control and volume control ventilation are the most preferred modes of ventilator techniques available in the intraoperative period. The study compared the intraoperative ventilator and blood gas variables of volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) in patients undergoing single level anterior cervical discectomy and fusion (ACDF).Methods:After obtaining Institutional Ethical Committee approval and informed consent, sixty patients scheduled for single level ACDF surgery performed in supine position under general anaesthesia were included. Group V (30 patients) received VCV and Group P (30 patients) received PCV. The primary objective was oxygenation variable PaO2/FiO2 at different points of time i.e. T1–20 min after the institution of the ventilation, T2–20 min after placement of the retractors and T3–20 min after removal of the retractors. The secondary objectives include other arterial blood gas parameters, respiratory and haemodynamic parameters. NCSS version 9 statistical software was used for statistics. Two-way repeated measures for analysis of variance with post hoc Tukey Kramer test was used to analyse continuous variables for both intra- and inter-group comparisons, paired sample t-test for overall comparison and Chi-square test for categorical data.Results:The primary variable PaO2/FiO2 was comparable in both groups (P = 0.08). The respiratory variables, PAP and Cdynam were statistically significant in PCV group compared to VCV (P < 0.05), though clinically insignificant. Other secondary variables were comparable. (P > 0.05)Conclusion:Clinically, both PCV and VCV group appear to be-equally suited ventilator techniques for anterior cervical spine surgery patients.

Can Cervical Arthroplasty Impact Alignment? A Comparison of the Synergy Disc with Cervical Fusion

Background context: Synergy disc is a new cervical disc prosthesis that incorporates alignment restoration while providing full intervertebral disc kinematics.Purpose: This follow-up study with 40 Synergy Disc patients with 24-month follow-up compared cervical alignment changes with a retrospective cohort of 30 single level anterior cervical discectomy and fusion (ACDF) patients.Study design/setting: The pilot trial was a multi-center, prospective, consecutive patient enrollment study using the Synergy Disc for the treatment of single and two-level degenerative disc disease of the cervical spine.Patient sample: The procedure was performed on 43 patients (45 implants) with follow-up on 40 patients (42 implants). For the historical cohort ACDF arm, 30 patients with similar follow-up with single level anterior discectomy, fusion and plating were used for segmental lordosis measurements.Outcome measures: For the Synergy Disc group, the kinematic parameters included: range of motion (ROM), shell angle (SA), disc height (DH), sagittal plane translation and center of rotation (COR) in the X and Y direction. Standard assessments of clinical outcomes were also measured (Neck Disability Index, Visual Analog Scale). For the fusion arm, only functional spinal unit (FSU) angle was recorded using a single pre-operative and post-operative standing lateral cervical radiograph.Methods: In the Synergy Disc group, static and dynamic radiological assessments were performed in 43 consecutive patients prior to the placement of the Synergy Disc. Forty patients were studied for the course of the study protocol (3 patients lost to follow-up). For the Synergy Disc group, all kinematic parameters were examined at a minimum of 24 months follow-up. Neck Disability Index and Visual Analog Scale for arm and neck pain were collected and analyzed. For the fusion group, standing lateral radiographs were reviewed.Results: At a mean of 28 months with all patients having a minimum of 24-month follow-up (40 patients, 42 implants), the average SA of the Synergy Disc was maintained at 6 ± 2.7˚ of lordosis. There was significant improvement in all clinical outcome measures. In the fusion group, with a similar follow-up period, there was a 4˚ increase in lordosis of the FSU.Conclusion: The Synergy Disc had an endplate angle of 6 ± 2.7˚ at 2 years following surgery. This was comparable to the lordotic correction provided by an anterior cervical discectomy with interbody fusion and plating.