After Anterior Cervical Discectomy And Fusion Surgery Research Articles

The Effect of Interbody Cage Parameters on the Rate of Subsidence in Single-Level Anterior Cervical Discectomy and Fusion (ACDF): A Retrospective Analysis of 98 Patients.

Subsidence is arelatively common consequence after anterior cervical discectomy and fusion (ACDF) surgery. This study aimed to identify the effect of radiological and non-radiological risk factors on subsidence after a single-level ACDF surgery with cage and plate. This is a retrospective cohort study of patients who underwent ACDF for radiculopathy or myelopathy at an academic center, University of Kentucky Albert Chandler Hospital, Lexington, Kentucky, United States, between January 2010 and January 2020.Subsidence was defined as the sinking of the interbody cage into the vertebral body at either the superior end plate (SEP) or inferior end plate (IEP) at the ACDF level and was measured manually on lateral standing x-ray. The numerical amount of subsidence was measured in millimeters as the sum of subsidence in the SEP and IEP and was further categorized into subsidence2 and subsidence3 (i.e., presence of subsidence > 2 mm and subsidence > 3 mm, respectively). Multivariateregression analysis was used to assess the effect of variables such as age, gender, body mass index (BMI), tobacco use, follow-up length, cage type, anterior cage height, posterior cage height, anterior cage height ratio, posterior cage height ratio, cage position, cage-end plate interface and cervical alignment on outcomes such as subsidence, subsidence2, and subsidence3. A total of 98 patients were included, of which 46 (47.1%) were male. The mean age of the population was 47.6±8.4 years. Fifty-one patients (52%) experienced subsidence more than 3 mm. Anterior disc height ratio (ADHR) was calculated by dividing the anterior cage height by the anterior disc height (pmADH). The posterior disc height ratio (PDHR) was calculated by dividing the posterior cage height by the posterior disc height (pmPDH). There was no significant correlation between ADHR and PDHR with subsidence, (p=0.93 and 0.56, respectively). Gender, age, BMI, and smoking status did not affect subsidence either. Cage type significantly affected subsidence with a higher subsidence rate in VG2 cages compared to Bengal cages (p=0.05). This study showed that in patients undergoing single-level ACDF with cage and plate, cage size and in particular cage height (if adjusted for individual patients) did not affect subsidence. Other factors such as cage-endplate interface, cage depth in interbody space, and cervical alignment did not significantly affect subsidence either. This might be attributable to the use of an anterior plating system that conducts the force and reduces the stress on the graft-bone interface.

Pseudoarthrosis after anterior cervical discectomy and fusion: rate of occult infections and outcome of anterior revision surgery

BackgroundPseudoarthrosis after anterior cervical discectomy and fusion (ACDF) is relatively common and can result in revision surgery. The aim of the study was to analyze the outcome of patients who underwent anterior revision surgery for pseudoarthrosis after ACDF.MethodsFrom 99 patients with cervical revision surgery, ten patients (median age: 48, range 37–74; female: 5, male: 5) who underwent anterior revision surgery for pseudoarthrosis after ACDF with a minimal follow up of one year were included in the study. Microbiological investigations were performed in all patients. Computed tomography (CT) scans were used to evaluate the radiological success of revision surgery one year postoperatively. Clinical outcome was quantified with the Neck Disability Index (NDI), the Visual Analog Scale (VAS) for neck and arm pain, and the North American Spine Society Patient Satisfaction Scale (NASS) 12 months (12–60) after index ACDF surgery. The achievement of the minimum clinically important difference (MCID) one year postoperatively was documented.ResultsOccult infection was present in 40% of patients. Fusion was achieved in 80%. The median NDI was the same one year postoperatively as preoperatively (median 23.5 (range 5–41) versus 23.5 (7–40)), respectively. The MCID for the NDI was achieved 30%. VAS-neck pain was reduced by a median of 1.5 points one year postoperatively from 8 (3–8) to 6.5 (1–8); the MCID for VAS-neck pain was achieved in only 10%. Median VAS-arm pain increased slightly to 3.5 (0–8) one year postoperatively compared with the preoperative value of 1 (0–6); the MCID for VAS-arm pain was achieved in 14%. The NASS patient satisfaction scale could identify 20% of responders, all other patients failed to reach the expected benefit from anterior ACDF revision surgery. 60% of patients would undergo the revision surgery again in retrospect.ConclusionOccult infections occur in 40% of patients who undergo anterior revision surgery for ACDF pseudoarthrosis. Albeit in a small cohort of patients, this study shows that anterior revision surgery may not result in relevant clinical improvements for patients, despite achieving fusion in 80% of cases.Level of evidenceRetrospective study, level III.

Analysis of risk factors for non-fusion of bone graft in anterior cervical discectomy and fusion: A clinical retrospective study

BackgroundBone graft fusion is a major concern among surgeons after Anterior Cervical Discectomy and Fusion (ACDF) surgery as non-fusion may lead to further physical and drug therapies. MethodsThe related risk elements of non-fusion of bone graft in ACDF surgery were retrospectively assessed. Patients receiving ACDF operation in our hospital from January 2015 to December 2019 were retrospectively analyzed. According to the criteria, 107 study subjects were recruited with a total of 164 surgical segments. The general information of patients, bone graft materials, imaging parameters, and clinical efficacy was recorded. T-test, chi-square test and binary logistic regression evaluation were employed to explore the risk factors of bone graft nonunion. ResultsLow housefield unit (HU) value, diabetes, allogeneic bone, and hydroxyapatite (HA) artificial bone could be risk factors for bone graft fusion in ACDF surgery. Further multivariate analysis was performed and confirmed those related factors of bone graft non-fusion including low HU value (non-fusion rate: 32.53% [27/83], OR = 5.024, p = 0.025), diabetes (non-fusion rate: 53.33% [8/15], OR = 4.776, p = 0.031), allogeneic bone (18.57% [13/70], OR = 3.964, p = 0.046), and artificial bone (68.29% [28/41], OR = 50.550, p < 0.01). ConclusionBy looking at bone graft fusion, selecting autologous iliac bone is an ideal selection to avoid non-fusion of bone graft in ACDF. Diabetes was more important predictor of bone graft nonunion than low HU value. Larger sample size and longer follow-up are required to further confirm these findings in the future.

Safety and Efficacy of Local Steroid Application on Dysphagia Following Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-analysis.

A systematic review and meta-analysis. To evaluate the safety and efficacy of local steroid application (LSA) on dysphagia after anterior cervical discectomy and fusion (ACDF). Dysphagia is one of the most common adverse events in the early postoperative period of ACDF. LSA is reported as an effective method to reduce the swelling of soft tissues, thereby decreasing the incidence of dysphagia. However, the safety and efficacy of LSA on dysphagia after ACDF need to be systematically reviewed and analyzed. A comprehensive literature search was carried out in the database PubMed, Web of Science, EMBASE, Clinical key, Cochrane library, and Wiley Online Library to screen papers that report LSA in ACDF surgery. The Cochrane Collaboration tool and a methodological index for nonrandomized studies were used for the assessment of study quality. Data were analyzed with the Review Manager 5.3 software. A total of 10 studies were included. The results revealed no significant differences between the steroid group and the control group in ACDF regarding postoperative drainage, estimated blood loss, and neck disability index score ( P > 0.05). LSA significantly alleviates visual analog scale score for neck pain (or odynophagia) ( P < 0.05), reduces the length of hospital stay (weighted mean difference, -1.00 (-1.05 to -0.95); P < 0.001), and mitigates dysphagia rate and prevertebral soft-tissue swelling in the early postoperative period ( P < 0.05). There seemed to be no significant increase in the complication rate and steroid-related adverse events in the steroid group compared with the control group ( P < 0.05). LSA shows advantages in reducing the length of hospital stay, decreasing dysphagia rate, and mitigating prevertebral soft-tissue swelling in the early postoperative period of ACDF. Further large-scale studies are urgently required for the development of a standard protocol for LSA and further analysis of potential delay complications.

Intraoperative Monitoring of the Recurrent Laryngeal Nerve with Electromyography Endotracheal Tube in Anterior Cervical Discectomy and Fusion

ObjectiveRecurrent laryngeal nerve (RLN) injury is common complication after anterior cervical discectomy and fusion (ACDF). In the present study, we evaluated RLN function during ACDF surgery using intraoperative RLN monitoring with an electromyography-endotracheal tube (EMG-ET).MethodsIn the present study, we retrospectively compared the postoperative RLN injury outcomes between patients who had undergone ACDF with and without an EMG-ET at Vajira Hospital from March 2017 to March 2022.ResultsThe analysis included 85 patients, 58 (68.2%) of whom had undergone surgery without an EMG-ET and 27 (31.8%) with an EMG-ET. Of the no EMG-ET group, 8 (13.8%) and 1 (1.7%) patient had developed immediate postoperative dysphagia and hoarseness, respectively, with complete recovery within 12 months. In the EMG-ET group, 2 (7.4%) and 1 (3.7%) patient had developed dysphagia and hoarseness, respectively, with complete recovery within 3 months for all 3 patients. Persistent postoperative RLN palsy had occurred in 5 patients (8.6%) without the EMG-ET but in none of the patients with the EMG-ET. The sensitivity and specificity for the use of intraoperative EMG-ET to detect a potential RLN injury were 67.0% and 96.0%, respectively. The use of an EMG-ET reduced the retractor time (P = 0.003), and a retractor time of <70 minutes was associated with a decreased incidence of postoperative RLN injury (odds ratio, 0.122; 95% confidence interval, 0.015–0.981; P = 0.048).ConclusionsThe use of an EMG-ET for RLN monitoring during ACDF surgery was helpful in detecting postoperative RLN injury with fair sensitivity and high specificity and resulted in a shorter retractor time, thereby significantly reducing the risk of postoperative RLN injury.

Does titanium cage subsidence affect clinical outcomes in ACDF surgery? A tertiary centre experience.

Cage subsidence after anterior cervical discectomy and fusion (ACDF) surgery has been well documented with rates of up to 40%. Cages fill the void after cervical discectomy and promote fusion. These materials have different biomechanical profiles with differing rates of subsidence. This retrospective cohort study aimed to determine subsidence rates specifically associated with the novel Emerging Implant Technologies (EIT) titanium cage, identify risk factors associated with subsidence, and evaluate whether subsidence affects clinical outcomes. ACDF with insertion of stand-alone EIT cage was performed in 39 patients (64 levels) between December 2016 and February 2019 with a median follow-up of 11 months. Patients were classified into two groups; subsidence and non-subsidence, and were compared in terms of the resultant clinical outcomes as well as presence of risk factors. Health-related quality of life (HRQOL) outcomes were assessed using Visual Analogue Scale (VAS) for neck and arm pain, EuroQol 5-Dimension 5-Level (EQ-5D-5L), EuroQol Visual Analogue Scale (EQ VAS) and Neck Disability Index (NDI) scores. Cage subsidence (>3mm) was present in nine patients (23%), which corresponded to ten levels treated (16%). Development of subsidence was not associated with gender (p = 0.12), age (p = 0.27), smoking (p = 0.13), number of treatment levels (p = 0.10) or cage size used (p = 0.34). It had no effect on any of the HRQOL outcomes, namely VAS Neck (p = 0.07), VAS Arms (p = 0.08), EQ-5D-5L (p = 0.36), EQ VAS (p = 0.85) and NDI (p = 0.80). The EIT cage seems to be associated with lower rates of subsidence compared with other cage types. Cage subsidence was not associated with HRQOL outcomes or risk factors.

How to reconstruct the lordosis of cervical spine in patients with Hirayama disease? A finite element analysis of biomechanical changes focusing on adjacent segments after anterior cervical discectomy and fusion

PurposeTo compare the biomechanical changes of adjacent segments between patients with Hirayama disease and non-pathological people after anterior cervical discectomy and fusion (ACDF) operation, and to explore the optimal degree of local lordosis reconstruction during surgery.MethodsA young male volunteer was recruited to establish a three-dimensional finite element model of the lower cervical spine based on the CT data. By adjusting the bony structures and simulating the operation process, the models of non-pathological individuals before and after ACDF, patients with Hirayama disease before and after ACDF, and different local lordosis angles were established. Then, the postoperative range of motion (RoM) and stress of the adjacent segments under flexion, extension, left bending, right bending, left rotation and right rotation were recorded and compared.ResultsThe RoM and stress of all segments of lower cervical spine in patients with Hirayama disease are higher than those in non-pathological individual, and this trend still exists after ACDF surgery. When the local lordosis angle is under physiological conditions, the RoM and stress of the adjacent segments are minimum.ConclusionCompared with non-pathological people, Hirayama disease patients have differences in cervical biomechanics, which may lead to cervical hypermobility and overload. After ACDF, the possibility of adjacent segments degeneration is greater than that of non-pathological people. When the operation maintains the physiological local lordosis angle, it can slow down the degeneration.

The Effects of Rehabilitation Following Anterior Cervical Microdiscectomy and Fusion Surgery.

To determine the effects of physical therapy and exercise programs that was performed after anterior cervical discectomy and fusion (ACDF) surgery on patient?s pain treatment, a retrospective study was designed. Of the 127 patients without neurological deficit who underwent ACDF surgery in our clinic in 2019 and 2020 for single-level cervical disc herniation, 40 patients (including 23 men and 17 women) were enrolled. The mean age of the patients was 45.5 years. The patients were separated into two groups. Group A comprised 20 patients who did not apply for a post-ACDF physical therapy and exercise program. Group B comprised 20 patients who applied for a 6-month post-ACDF physical therapy and exercise program and complied with it. The Oswestry Deficiency Index (ODI), visual analog pain scale (VAS), and C2-7 cervical lordosis angle were evaluated. The C2-7 cervical lordosis angles were individually calibrated and calculated for each patient using Surgimap. The relationships between the results were compared using Wilcoxon biostatistics test. The ODI, VAS, and C2-7 cervical lordosis angle parameters of Groups A and B were statistically compared. No significant differences in the ODI, VAS, and C2-7 cervical lordosis angle 2 days after surgery and C2-7 cervical lordosis angle 6 months after surgery were observed between the two groups; however, significant differences were observed in VAS and ODI values 6 months after physical therapy in Group B and in VAS and ODI values 6 months after surgery in Group A. No significant difference in C2-7 cervical lordosis angle 6 months after surgery was observed between post-physical therapy Group B and postoperative Group A. Physical therapy and exercise program performed early after ACDF enhances and improves pain management and does not cause any changes in the restoration of cervical misalignment.

Progression of Ossification of Posterior Longitudinal Ligament After Anterior Cervical Discectomy and Fusion in Military Patients Exposed to Minor Trauma.

Ossification of the posterior longitudinal ligament (OPLL) can progress even after cervical spine surgery and may cause neurological injury as a result of minor trauma. The purpose of this study was to investigate the preventive factors associated with OPLL progression after anterior cervical discectomy and fusion (ACDF), a procedure commonly performed in clinical practice. We retrospectively investigated 295 male soldiers who underwent ACDF surgery between 2012 and 2017. Patients who were followed up for >12 months using dynamic radiography and computed tomography (CT) were included in the study. Radiological parameters investigated included OPLL progression, C2-C7 angles on dynamic radiography, segmental angles, C2-C7 cervical sagittal vertical axis (C2-C7 SVA), and the T1 slope. These parameters were measured preoperatively and 1 year postoperatively. A total of 49 patients were enrolled, and 10 patients were confirmed to have OPLL progression. Comparison between the OPLL progression and non-progression groups showed no statistically significant differences in pre- and postoperative cervical range of motion. However, statistically significant differences were observed in the postoperative neutral C2-C7 angle (progression -3.9°±6.4° vs. non-progression -13.4°±7.9°, p=0.001) and the SVA change (progression 5.8±7.9 mm vs. non-progression -3.7±6.3 mm, p=0.00). The cutoff values were -8.01° for the postoperative neutral C2-C7 angle and 1.4 mm for SVA changes. Increased SVA (>1.4 mm) and a small postoperative neutral C2-C7 angle (>-8.01°) 1 year after ACDF were associated with OPLL progression. It is important to be mindful of these factors during follow-up after ACDF, because additional surgical treatment may be necessary for OPLL progression due to neurological injury caused by minor trauma.

Dysphagia Weakly Correlates With Other Patient-Reported Outcomes After Anterior Cervical Discectomy and Fusion.

IntroductionDysphagia is a common complication after anterior cervical discectomy and fusion (ACDF), but it is not a routinely asked question in legacy patient-reported outcome measures (PROMs). This study analyzes whether there are associations between dysphagia and legacy outcome measures.MethodsWe retrospectively reviewed 168 patients who underwent ACDF surgery from 2017 to 2019 at a single institution. Demographics, anthropometric data, Neck Disability Index (NDI), Visual Analog Scale (VAS)-Arm and VAS-Neck Pain scores, Patient-Reported Outcomes Measurement Information System (PROMIS)-Physical and PROMIS-Mental scores, Charlson Comorbidity Index (CCI), and Eating Assessment Tool-10 (EAT-10) were obtained for each patient preoperatively and at one, three, six, and 12 months postoperatively. Pearson’s correlation coefficients were used to evaluate the bivariate correlations between legacy, PROMIS, and EAT-10 measures.ResultsSignificant but weak correlations existed between NDI and EAT-10 at one, three, and six months postoperatively (correlation coefficient (R) = 0.31, 0.42, and 0.34 at one, three, and six months, p < 0.001) and VAS-Neck Pain and EAT-10 scores at one, three, and six months postoperatively (R = 0.27, 0.30, and 0.28 at one, three, and six months, p ≤ 0.004). Both PROMIS-Physical and PROMIS-Mental scores showed significant but weak correlations with EAT-10 scores at three and six months postoperatively (R = -0.29 and -0.25, p ≤ 0.01, at three months and R = -0.25 and -0.28, p < 0.01, at six months). In all comparisons of EAT-10 scores with legacy outcome measures, the significance of correlations disappeared by 12 months postoperatively. In addition, there was a positive association between CCI and EAT-10 score (β = 0.37, p < 0.05).ConclusionWeak correlations exist between self-reported dysphagia scores and legacy patient-reported outcome measures in patients undergoing ACDF. The correlation strength decreases over time; therefore, dysphagia scores should be reported separately when looking at outcomes after ACDF. Patients with more comorbidities are also at increased risk for dysphagia.

Impact of adjacent pre-existing disc degeneration status on its biomechanics after single-level anterior cervical interbody fusion

Background and objectiveMechanics and biology may be interconnected and amplify each other during disc degeneration. It remains unknown the influence of pre-existing disc degeneration and its impact on adjacent segment degeneration (ASD) after anterior cervical discectomy and fusion (ACDF). This study aimed to discuss the necessity of including degenerated adjacent segments in single-level ACDF surgery from a biomechanical view. MethodsA poroelastic C2-T1 finite element model was created and validated. A C5-C6 ACDF model was developed based on this normal model. Moderate C4-C5 disc degeneration was created by appropriately modifying the morphology and tissue material properties in this fusion model. Degenerative morphology was modeled based on Thompson's grading system and Walraevens's scoring system for cervical spine, including disc height, whole disc area, nucleus pulposus (NP) area, endplate sclerosis and curvature. Stresses in disc and endplate and loads in facet joint were computed under moment loads in the fusion models with normal and pre-existing degenerative disc condition. ResultsAs for the adjacent disc, the stress values in degenerative condition were 7.41%, 5% and 5.26% larger than that in normal situation during extension, axial rotation and lateral bending motion, respectively. The disc stress changes mainly stemmed from annulus fibrosus (AF) tissue, but not NP. In the endplate, stress values of degeneration status were 4.17, 4.35 and 6.06% larger than that of normal condition under axial rotation, lateral bending and extension. The facet load magnitudes of pre-existing degeneration were 11.28, 11.57, 11.78 and 11.42% greater than that of normal condition in flexion, extension, axial rotation and lateral bending motion. ConclusionPre-existing degenerated disc experience increased biomechanical changes in adjacent segment after single-level ACDF. It may pose a long-term cumulative problem related to biomechanics in cervical spine after fusion. Before surgery, surgeons should be careful about selecting the fusion level.

Biomechanical Evaluation of a Novel S-Type, Dynamic Zero-Profile Cage Design for Anterior Cervical Discectomy and Fusion with Variations in Bone Graft Shape: A Finite Element Analysis

Variations in cage design, material, and graft shape can affect osteointegration and adjacent segment range of motion (ROM) and stress after anterior cervical discectomy and fusion (ACDF) surgery. This study aimed to evaluate the biomechanical properties of a novel dynamic cervical cage design in both titanium (Ti) and polyether ether ketone (PEEK) with variations in bone graft shape using a single level ACDF (FE) model. A 3-dimensional C3-C6 FE model was developed using computed tomography scan data from a healthy male subject. The novel S-shaped dynamic interbody fusion cage with a zero-profile fixation was inserted at the C4-C5 level with 4 different bone graft shapes (square, circular, rectangular, and elliptical). Changes in segmental ROM and maximum von Mises stresses at the fusion and adjacent segments were analyzed. Both Ti and PEEK cages showed decreased ROM at the fusion and adjacent levels for all shapes of bone graft when compared with the intact spine model. The elliptical graft, for both Ti and PEEK cages, showed a lower percentage of reduction in segmental ROM at the fusion and adjacent levels (0%-5.6%) when compared with other graft shapes (0%-12%). Maximum stresses at the fusion level were lowest in Ti cage with elliptical graft (229.8-347.6 MPa) when compared with other shapes (241.2-476.2 MPa) in flexion, extension, and lateral bending. For the bone graft, maximum stresses were highest on the elliptical-shaped bone graft in flexion and extension in the Ti cage, and in flexion and lateral bending in the PEEK cage. Both Ti and PEEK cages showed decreased ROM at the fusion and adjacent levels for all shapes of bone graft when compared with the intact spine model. In the Ti and PEEK dynamic cages, the elliptical shape bone graft showed decreased stress on the cage and increased stress on the bone graft. Further experimental and clinical studies are needed to confirm these encouraging biomechanical results of this novel dynamic, zero-profile fusion device with elliptical bone graft in ACDF surgery.

Biomechanical effect of different plate-to-disc distance on surgical and adjacent segment in anterior cervical discectomy and fusion - a finite element analysis

BackgroundThe plate-to-disc distance (PDD) is an important factor affecting the degeneration of adjacent segments after anterior cervical discectomy and fusion (ACDF). However, the most suitable PDD is controversial. This study examined the adjacent intervertebral disc stress, bone graft stress, titanium plate stress and screw stress to evaluate the biomechanical effect of different PDD on surgical segment and adjacent segment following C5/C6 ACDF.MethodsWe constructed 10 preoperative finite element models of intact C4–C7 segments and validated them in the present study. We simulated ACDF surgery based on the 10 intact models in software. We designed three different distance of plate-to-disc titanium plates: long PDD (10 mm), medium PDD (5 mm) and short PDD (0 mm). The changes in C4/C5 and C6/C7 intervertebral disc stress, bone graft stress, titanium plate stress and screw stress were analyzed.ResultsThe von Mises stress of C4/C5 and C6/C7 intervertebral discs had no significant differences (P > 0.05) in three different PDD groups. Titanium plate stress increased as the PDD decreased. The bone graft stress and screws stress decreased as the PDD decreased. The maximum stress of each part occurred was mostly in the conditions of rotation and lateral bending.ConclusionsThe PDD has no effect on adjacent intervertebral disc stress, but it is an important factor that affecting the bone graft stress, titanium plate stress and screws stress after ACDF. Shorter PDD plate can provide better stability to reduce stress on screws and bone graft, which may be helpful to prevent cage subsidence, pseudarthrosis and instrument failure. This can serve as a reference for clinical choice of plate.

Comparison of Postoperative Opioid Utilization in an ACDF Cohort: Narcotic Naive Patients Versus Preoperative Opioid Users.

A retrospective cohort study. To compare the postoperative opioid utilization rates and costs after anterior cervical discectomy and fusion (ACDF) procedures between groups of patients who were preoperative opioid users versus opioid naive. Opioid medications are frequently prescribed after ACDF procedures. Given the current opioid epidemic, there is increased emphasis on early identification of patients at risk for prolonged postoperative opioid use. Records from patients diagnosed with cervical stenosis who underwent a ≤3-level index ACDF surgery between 2007 and 2017 were collected from a large insurance database. International Classification of Diseases diagnosis/procedure codes, Current Procedural Terminology codes, and generic drug codes were used to search clinical records. Two cohorts were established: a group of patients who utilized opioids preoperatively and a group of patients who were opioid naive at the time of surgery. The 1-year utilization and costs of postoperative therapies were documented for each group. The preoperative opioid use cohort contained 4485 patients (61.6%), whereas the opioid-naive cohort included 2799 patients (38.4%). Postoperatively, 86.6% of the preoperative opioid use group continued to use opioids, whereas 59.0% of the opioid-naive group began using opioids. Patients who utilized opioids preoperatively were 4.48 times more likely (95% confidence interval, 3.99-5.02, P<0.001) to use opioids postoperatively and 4.30 times more likely (95% confidence interval, 3.10-5.94, P<0.001) to become opioid dependent compared with opioid-naive patients. In addition, after normalization, patients in the preoperative opioid use group utilized 3.7 times more opioid units/patient and billed for 5.3 times more dollars/patient than opioid-naive patients. In patients with cervical stenosis who undergo an ACDF procedure, the postoperative utilization and costs of opioids seem to be substantially higher in patients with preoperative opioid use compared with opioid-naive patients. Efforts should be made to avoid opioid use as a component of conservative management before surgery. Level III.

A Comparison of Clinical Outcomes between Early Cervical Spine Stabilizer Training and Usual Care in Individuals following Anterior Cervical Discectomy and Fusion.

Objectives Early physical therapy (PT) with specific stabilization training has been shown to benefit individuals after lumbar spinal surgery but has not been studied in patients after cervical spine surgery. The primary purpose of this study was to compare clinical outcomes between early cervical spine stabilizer (ECS) training and usual care (UC) in patients after anterior cervical discectomy and fusion (ACDF) surgery. The secondary purpose was to determine test-retest reliability of strength and endurance tests of cervical spinal stabilizers in this patient population. Methods Forty participants who were scheduled for ACDF surgery were randomized into either the ECS group or the UC group. After surgery, participants received their assigned group intervention during their hospital stay and continued their assigned intervention for 12 weeks. All participants had phone follow-ups twice during the first 6 weeks to address questions or problems. Clinical outcome measures including pain level using the Numeric Pain Rating Scale (NPRS), disability level using the Neck Disability Index (NDI), Craniocervical Flexor Strength (CCF-S), and Craniocervical Flexor Endurance (CCF-E) were collected three times: before surgery and 6 and 12 weeks after surgery. Test-retest reliability was assessed in the first 10 participants. Results There was no significant interaction between the groups over time for any of the outcome measures. However, all participants made significant improvements in all four outcome measures at 6 and 12 weeks post surgery. The results showed good-to-excellent test-retest reliability for the CCF-S and CCF-E tests. Conclusions Both ECS training and UC resulted in the same amount of improvement at 6 and 12 weeks; therefore, both therapy approaches appear to have similar and positive effects on patients in their first 3 months of recovery after ACDF. Both the CCF-S and CCF-E tests can be used reliably to assess the strength and endurance of the cervical spinal stabilizers for patients after ACDF surgery. The study was registered with the ClinicalTrials.gov (NIH, U.S. National Library of Medicine, identifier # NCT01519115) Protocol Registration system.

The Impact of Multiple Comorbid Mental Health Disorders on Health-related Quality of Life Following ACDF

Retrospective comparative study. The goal was to determine whether comorbid depression and/or anxiety influence outcomes after anterior cervical discectomy and fusion (ACDF) for patients with degenerative cervical pathology. The role preoperative mental health has on patient reported outcomes after ACDF surgery is not well understood. Patients undergoing elective ACDF for degenerative cervical pathology were identified. Patients were grouped based on their preoperative mental health comorbidities, including patients with no history, depression, anxiety, and those with both depression and anxiety. All preoperative medical treatment for depression and/or anxiety was identified. Outcomes including Physical Component Score (PCS-12), Mental Component Score (MCS-12), Neck Disability Index (NDI), Visual Analogue Scale neck pain score (VAS Neck ), and Visual Analogue Scale arm pain score (VAS Arm) were compared between groups from baseline to postoperative measurements using multiple linear regression analysis-controlling for factors such as age, sex, and body mass index, etc. A P-value <0.05 was considered statistically significant. A total of 264 patients were included in the analysis, with an average age of 53 years and mean follow-up of 19.8 months (19.0-20.6). All patients with a diagnosis of depression or anxiety also reported medical treatment for the disease. The group with no depression or anxiety had significantly less baseline disability than the group with 2 mental health diagnoses, in MCS-12 (P=0.009), NDI (P<0.004), VAS Neck (P=0.003), and VAS Arm (P=0.001) scores. Linear regression analysis demonstrated that increasing occurrence of mental health disorders was not a significant predictor of change over time for any of the outcome measures included in the analysis. Despite more severe preoperative symptoms, patients with a preoperative mental health disorder(s) demonstrated significant improvement in postoperative outcomes after ACDF. No differences were identified in postoperative outcomes between each of the groups. Level III.

Radiographic measurements of cervical alignment, fusion and subsidence after ACDF surgery and their impact on clinical outcome.

Some recent studies indicate correlations between cervical alignment and clinical outcome after anterior cervical discectomy and fusion (ACDF) surgery. However, there still are no established criteria for the interpretation of alignment, fusion and subsidence in relation to clinical outcome. A retrospective analysis of 208 radiographs of patients following ACDF with stand-alone PEEK cage implantation was performed. The measurements were obtained on plain radiographs in lateral and anteroposterior projections as well as flexion/extension radiographs. Cervical alignment was measured using the Gore, Laing and Cobb methods; fusion was evaluated by an assortment of radiographic hallmarks: the presence of bridging bone, the Cobb angle and the distances between the tips and bases of the spinous processes of the operated segments, respectively. For assessment of subsidence, we used the Mochida method in addition to ventral and dorsal segmental height reduction. Correlation analysis between the different radiological characteristics and clinical outcome at a minimum follow-up of 12months was conducted. Two hundred and eight patients were evaluated for alignment, fusion and subsidence. Cervical alignment using the Gore and Cobb methods correlated among each other, but failed to exhibit significant correlation with clinical outcome. Interpretation of fusion rates varied greatly (43.9 to 89.4%) depending on the criteria used. Pearson coefficients between radiographic presence of pseudarthrosis and the measurements of the spinous process distances (0.595; p < 0.001), the Cobb angles (0.187; p = 0.007) and the presence of bridging bone (0.224; p < 0.001) each exhibited statistical significance. None of the methods employed significantly correlated with clinical outcome. Regarding subsidence, we found rates of 62%, 48% and 27% using the Mochida, ventral and dorsal segmental height reduction assessment methods, respectively. Pearson correlations between pairs of Mochida/ventral (r = 0.39; p = 0.66) and Mochida/dorsal (r = 0.007; p = 0.921) height reduction assessment methods were weak and no significant correlation between subsidence rates and clinical outcome was shown. All measured parameters varied depending in the measurement method used. This was most pronounced for fusion. There was a moderate positive correlation between neck pain and subsidence as measured by the Mochida method.

Anterior cervical discectomy and fusion for cervical myelopathy using stand-alone tricortical iliac crest autograft: Predictive factors for neurological and fusion outcomes.

The purpose of this article is to investigate the outcomes after anterior cervical discectomy and fusion (ACDF) surgery with stand-alone tricortical iliac crest autograft and to determine predictive factors for poor neurological recovery, non-union, graft collapse and loss of C2-C7 sagittal alignment. This was a retrospective study involving patients with cervical myelopathy who underwent ACDF surgery with stand-alone tricortical iliac autograft between 2006 and 2016, with a minimum 2-year postoperative follow-up. Outcomes included the change in Japanese Orthopaedic Association (JOA) scores clinically and timing of fusion, graft height and C2-7 angle measured on lateral radiographs. Any complication such as neurological deterioration, non-union, graft collapse or loss of angle was recorded. Delayed union was considered as radiological union identified only beyond postoperative 6 months. Risk factors including age, smoking, drinking, comorbidities and operative levels were analysed through a multivariate regression for their respective influences on the various outcomes. Of the 69 patients studied, none of the patients had non-union, while 33 (47.1%) achieved fusion in 6 months. The most common complications were anterior protrusion of graft (5.8%) and hoarseness (2.9%). The 1-year mean change in JOA score was 3.9 ± 2.7. The C2-7 angle gradually became more kyphotic, despite an initial lordosis correction intraoperatively. The graft height also gradually collapsed during subsequent follow-ups. Multivariate regression model suggested that diabetics (cumulative odds ratio 7.4) and drinkers (cumulative odds ratio 8.6) were associated with delayed union. ACDF using tricortical iliac crest autograft has satisfactory outcomes with low occurrence of complications. Diabetics and drinkers were predictors of delayed union.

Risk factors of second surgery for adjacent segment disease following anterior cervical discectomy and fusion: A 16-year cohort study.

Although the incidence of second surgery for adjacent segment disease (ASD) after anterior cervical discectomy and fusion (ACDF) has been reported, its risk factors remain elusive. Few studies have had a sufficiently large number of patients, long follow-up time, and high follow-up rate for investigation. To identify non-surgical risk factors of second surgery for ASD following ACDF, the study used a national cohort with comprehensive follow-up. All second ACDF surgery after one year from the first ACDF were identified as a consequence of ASD that required another surgery. A multivariate competing risk survival model, Kaplan-Meier survivorship, and average time to events were calculated. Among 38,149 patients who had the first ACDF, 1,092 (2.9%) later (mean 4.66 years) received a second ACDF surgery, during the nearly-perfect follow-up of 16 years. Young age and psychiatric disorders were independent risk factors. Patients who were aged under 40, 50, 60 and 70 years were, respectively, 4.56, 4.09, 3.09 and 2.17 times more likely than those older than 70 years. Also, patients with depression or psychoses were, respectively, 1.42 and 1.45 times more likely to have second surgery for ASD. (all p < 0.05). Young age and psychiatric disorders are independent risk factors of second ACDF surgery for ASD. Personalized strategies to ameliorate or postpone the development of ASD are therefore warranted for patients who need ACDF surgery.

Clinical effect observation of intravenous application of zoledronic acid in patients with cervical spondylosis and osteoporosis after anterior cervical discectomy and fusion: A randomized controlled study.

To observe the clinical effect of zoledronic acid (ZA) in patients with cervical spondylosis and osteoporosis after anterior cervical discectomy and fusion (ACDF) surgery. All selected patients were divided into the study group and the control group according to the sequence of surgery time. In the study group, 5 mg (100 ml) of ZA was applied intravenously as intervention on the 5 day after ACDF surgery. Patients were followed up regularly after surgery. Forty-three cases completed the follow-ups (21/22), the neck disability index (NDI) score significantly decreased at the 3rd month after surgery in both groups, it came to a plateau at the 6th month after surgery, and it had some rise at the 12th month after surgery, but the NDI score was lower in the study group at the 12th month after surgery ( p < 0.05). C-telopeptide of type I collagen (CTX) and amino terminal propeptide of type I procollagen of bone turnover markers in the study group showed a downward trend after surgery, among which CTX decreased significantly and no significant changes in the control group. At the 12th month after surgery, the bone mineral density of lumbar spine area in the study group was significantly improved ( p < 0.05). During the 3rd and the 6th month follow-up after surgery, 1/2 osteogenesis rate of the study group was significantly higher ( p < 0.05). However, all patients in the two groups obtained stable fusion at the 12th month follow-up after surgery. For patients with cervical spondylosis and osteoporosis, intravenous application of ZA after ACDF surgery can shorten the time of cervical osteogenesis, promote local bone graft fusion, and improve the postoperative clinical effect to some extent.