UNASSIGNED: Anterior cervical discectomy and fusion (ACDF) is a common cervical procedure with more than 137,000 cases in the United States (U.S.) each year. Historically, ACDF has been a relatively safe procedure despite encountering vital anatomical structures that can risk serious complications. One particularly dangerous sequela of ACDF is the risk of lacerating the vertebral artery (VA). While VA injuries are rare (0.5% of cases), it is crucial for surgeons to prevent this potentially deadly complication with thorough knowledge of VA anatomy. The VA is commonly protected within the transverse foreman; however, anomalies can exist with the artery potentially being found more medial or proximal within the surgical site than expected. The purpose of this article is to report an anomaly found in a cadaveric specimen, where the VA courses within 2 mm of an ACDF plate.
UNASSIGNED: A 66-year-old male with a past medical history of coronary artery disease passed away due to complications of a myocardial infarction. During cadaveric dissection, it was discovered that the donor had undergone a previous 3-level (C4-C7) ACDF procedure for an unknown reason. Under further examination, the left VA was observed to take an anomalous medially tracking course before eventually entering the transverse foramina of C5. Left anterior tubercles were absent at the level of C5 and C6 with prominent osteophytes found on the anterior tubercles/transverse foramina of the contralateral side.
UNASSIGNED: There are no studies published on the anatomy of VA variants and their implications on ACDF procedures. ACDF was found to have complication rates in 13.2% of cases. VA variants are observed in up to 20% of the U.S. population and VA injury in ACDF procedures has a rate near 0.5%. With anatomic variations leading to a higher risk of injury, surgeons are required to take further precautionary steps before operating including ordering computed tomography angiography or magnetic resonance angiography films. Understanding the detailed anatomy of the VA and its variants is critical. Using the perspectives of orthopedic spine surgeons, this study supplements the literature on potential VA anomalies encountered in ACDF procedures.

UNASSIGNED: The anatomic interplay and overlap between the cervical spine and the shoulder constitutes a challenge for shoulder and spine surgeons, as symptoms of spine and shoulder pathologies are often similar and may lead to entity misdiagnosis.
UNASSIGNED: PubMed, Cochrane, and Google Scholar (page 1-20) searches were updated to October 2023 in search of the qualified papers. Boolean Operators were used with a combination of the keywords \"spine\" OR \"neck\" And \"Shoulder\". Furthermore, reference lists from papers were also searched to find literature.
UNASSIGNED: It is of pivotal importance to conduct comprehensive preoperative clinical investigation to appropriately evaluate and assess the source of the pathology and the leading causes behind it. Certain markers can help guide surgeons towards etiologies, and these include areas of pain and physical exam findings with the arm squeeze test having the highest sensitivity and specificity for diagnosing cervical radiculopathy. As for the shoulder, despite its low sensitivity, the Yergason test had the highest specificity for diagnosing subacromial impingement. Local anesthetic injection can help as well in the diagnostic approach. Moreover, the interplay between these anatomic locations is not solely related to preoperative diagnosis. Studies have shown that previous surgery for cervical spine pathology may negatively affect the outcomes of shoulder procedures like arthroplasties.
UNASSIGNED: Shoulder and spine surgeons should be wary and vigilant of accurately diagnosing the etiology of the presenting symptoms to ensure proper management and optimize prognosis.

BACKGROUND: Postoperative retropharyngeal hematoma (PRH) and related dyspnea are rare but life-threatening complications following anterior cervical discectomy and fusion (ACDF) that require urgent recognition and treatment. However, current knowledge of PRH after ACDF is limited. Meanwhile, whether the morphological features of upper airway are the risk factors of PRH remains unknown.
OBJECTIVE: The study aimed to investigate the incidence, clinical features, and risk factors, especially the morphological features of upper airway, of PRH and related dyspnea following ACDF.
METHODS: A nested case‒control study.
METHODS: Consecutive patients who underwent ACDF at a single institute from January 2010 to December 2021 were retrospectively reviewed.
METHODS: The outcome measures included the incidence, clinical features, intervention, outcome and risk factors for PRH and related dyspnea.
METHODS: All patients with PRH were classified into the hematoma group. For each PRH subject, three control subjects without PRH were randomly selected as the control group. The clinical features, interventions and outcomes of patients were described. Potential risk factors were evaluated, including demographics, comorbidities, surgical characteristics, coagulation function, blood loss, preoperative blood pressure, and the morphological features of upper airway [prevertebral soft tissue thickness (PVT) and location of transverse arytenoid muscle (TAM) and epiglottis]. Univariate tests and multivariable logistic regression analysis were used to determine the risk factors for PRH. Subgroup analysis was also conducted for PRH patients with and without dyspnea.
RESULTS: Among the 10615 patients who underwent ACDF, 18 (0.17%) developed PRH. The median time from the index surgery to PRH formation was 8.5 hours (25 and 75 percentile: 4 hours to 24 hours). All the PRH patients initially presented with wound swelling. Twelve (0.11%) patients presented dyspnea due to PRH, 2 of whom received urgent intubation and 1 of whom received emergent tracheotomy. All patients underwent hematoma evacuation, and most of them presented with completely relieved symptoms after evacuation, except for one patient who died from ischemic hypoxic encephalopathy. A level between the epiglottis and the TAM (LET) greater than 2, ossification of posterior longitudinal ligament (OPLL) and higher diastolic blood pressure (DBP) before surgery were found to be risk factors for PRH formation. Subgroup analysis revealed that a smaller prevertebral soft tissue thickness at C5 was associated with the development of dyspnea.
CONCLUSIONS: This study is the largest study to date focusing on the PRH and related dyspnea after ACDF. Our study showed that the incidences of PRH and related dyspnea after ACDF were 0.17% and 0.11%, respectively. The predominant symptoms of PRH were wound swelling and acute dyspnea. Most PRH cases occurred in the acute postoperative period. We demonstrated the risk factors for PRH to be (1) OPLL, (2) LET≥2 and (3) higher DBP before surgery and advocate paying increased attention to upper airway morphological features for identifying the risk of PRH after ACDF. With urgent recognition and timely intervention, severe clinical outcomes could be avoided.

UNASSIGNED: Anterior cervical discectomy and fusion (ACDF) has proven to be a clinically efficient and cost-effective method for treating patients with degenerative cervical spine conditions. New intervertebral implant products are being developed to improve fusion and stability while decreasing complications. This study assesses the effectiveness of Tritanium C (Tri-C) Anterior Cervical Cage (Stryker) in the treatment of degenerative disk disease (DDD) of the cervical spine compared with polyetheretherketone (PEEK) cages.
UNASSIGNED: A retrospective cohort analysis was conducted using data prospectively collected from two institutions. Patients who underwent ACDFs for DDD using either the Tri-C cage or PEEK cage were identified. The patients\' demographics, comorbidities, operative variables, and baseline patient-reported outcomes (PROs) were collected. PROs included the Neck Disability Index (NDI) and numeric rating scale (NRS) for neck and arm pain. The primary outcomes included 3- and 12-month PROs as well as the rates of 90-day readmission, 90-day reoperation, and perioperative complication. The radiographic outcomes included rates of subsidence, cage movement, and successful fusion within 12 months. Multivariate linear regression models were run to identify variables predictive of 12-month PROs.
UNASSIGNED: A total of 275 patients who underwent ACDF were included in this study and were divided into two groups: PEEK (n=213) and Tri-C (n=62). Both groups showed improvement in neck and arm pain and NDI postoperatively. When Tri-C and PEEK were compared, no significant differences were observed in the 3- or 12-month changes in neck or arm pain or NDI. Furthermore, there were no differences in the rates of 90-day readmission, 90-day reoperation, and perioperative complication. Regression analysis revealed that Tri-C vs. PEEK was not a significant predictor of any outcome.
UNASSIGNED: Our results indicate that the use of porous titanium Tri-C cage during ACDFs is an effective method for managing cervical DDD in terms of PROs, perioperative morbidity, and radiologic parameters. No significant difference was observed in any clinical outcome between patients undergoing ACDF using the Tri-C cage and those in whom the PEEK cage was used.
UNASSIGNED: III.

UNASSIGNED: This study investigates the outcomes of treating neglected unstable Hangman\'s fractures through a single-stage Anterior Cervical Discectomy and Fusion (ACDF) procedure with tricortical iliac crest bone grafts.
UNASSIGNED: Five patients with neglected unstable Hangman\'s fractures, treated at our institution between March 2012 and March 2017, underwent C2-C3 ACDF. Functional outcomes were assessed using the Visual Analog Scale (VAS) score and Neck Disability Index (NDI), and neurological evaluation was done using the American Spinal Injury Association (ASIA) grading system. The radiological assessment included serial plain radiographs and a computed tomography scan at a 12-month follow-up.
UNASSIGNED: Postoperatively, C2-C3 angulation improved significantly, decreasing from 15° to 4.4°, and sagittal translation improved from 4.2 mm to 2 mm. The VAS score improved from 6.4 to 1.4 at 24 months postsurgery. Concurrently, NDI decreased from 70.4% to 14.8%. Fusion occurred in an average of 5.6 months. Neurologically, one patient improved from ASIA grade D to grade E, while the other four retained their grade E status.
UNASSIGNED: A single-stage ACDF with autologous iliac crest bone grafts is an effective surgical option for neglected type II/IIA Hangman\'s fractures, yielding satisfactory functional and radiological outcomes. This technique significantly corrects anterior translation and angulation, even in neglected cases, with the aid of intraoperative skull traction and plate reduction.

OBJECTIVE: To investigate the clinical effect of anterior cervical discectomy and fusion (ACDF) in the treatment of cervical spondylosis of vertebral artery type(CSA).
METHODS: The clinical data of 42 patients with CSA from January 2020 to January 2022 were retrospectively analyzed. There were 25 males and 17 females, aged from 30 to 74 years old with an average of (53.9±11.0) years old. There were 18 cases with single-segment lesions, 17 cases with two-segment lesions, and 7 cases with three-segment lesions. The American Academy of Otolaryngology-Head and Neck Surgery\'s Hearing and Balance Committee score (CHE), the Neck Disability Index (NDI) and the cervical curvature Cobb angle were recorded before surgery and after surgery at 6 months.
RESULTS: All 42 ACDF patients were followed up for 6 to 30 months with an average of (14.0±5.2) months. The operative time ranged from 95 to 220 min with an average of (160.38±36.77) min, the intraoperative blood loss ranged from 30 to 85 ml with an average of (53.60±18.98) ml. Tow patients had mild postoperative dysphagia, which improved with symptomatic treatment such as nebulized inhalation. CHE score decreased from (4.05±0.96) preoperatively to (2.40±0.70) at 6 months postoperatively (t=12.97, P<0.05). The number of improved vertigo at 6 months postoperatively was 38, with an improvement rate of 90.5%. NDI score was reduced from (34.43±8.04) preoperatively to (20.76±3.91) at 6 months postoperatively (t=11.83, P<0.05). The cervical curvature Cobb angle improved from (8.04±6.70)° preoperatively to (12.42±5.23)° at 6 months postoperatively (t=-15.96, P<0.05).
CONCLUSIONS: The ACDF procedure has outstanding clinical efficacy in treating CSA. The operation can rapidly relieve patients\' episodic vertigo symptoms by relieving bony compression and reconstructing cervical curvature. However, it is necessary to strictly grasp the indications for surgery and clarify the causes of vertigo in patients, and ACDF surgery is recommended for CSA patients for whom conservative treatment is ineffective.

Vascular complications succeeding anterior cervical spine surgery are rare, but their consequences represent a major burden for the patient. Cerebral infarction following anterior cervical discectomy and fusion (ACDF) is uncommon. However, screening for risk factors before surgery should become mandatory. We present the case of a patient with no significant medical history who underwent ACDF for a C5/C6 herniated disc with myelopathy. Although the surgery was uneventful, after the surgery, partial right palpebral ptosis and miosis were noted, suggestive of Horner syndrome. On the fifth postoperative day, the patient experienced left hemiplegia and drowsiness. An emergency CT scan and cerebral MRI revealed ischemia in the right middle cerebral artery territory. The patient was transferred to a neurology center for mechanical thrombectomy, which revealed a complete occlusion of the right internal carotid artery. The procedure had to be halted due to blood extravasation at the internal carotid artery bifurcation to prevent further complications. An angio-CT examination of the cervical arteries exposed a soft atheromatous plaque on the right internal carotid artery, immediately after the bifurcation. Despite the patient having no significant medical history, blood tests indicated dyslipidemia. At the two-month follow-up, the patient remained hemiplegic, with mild dysphasia. Performing carotid and vertebral Doppler ultrasound before cervical spine surgery might be useful, whenever possible, to assess high-risk factors for ischemic events and avoid such debilitating complications.

OBJECTIVE: The goal of this study was to compare rates of dysphagia and patient-reported outcomes (PROs) following long-segment (≥ 3 levels) anterior cervical spinal fusion (ACF) and posterior cervical spinal fusion (PCF) at 3 and 12 months postoperatively. PROs were also compared for patients with dysphagia versus those without dysphagia.
METHODS: A prospectively collected quality improvement database was used to identify patients who had a long-segment cervical spinal fusion. Cohorts were divided into ACF and PCF groups. Eating Assessment Tool-10 scores and PROs were obtained for all patients preoperatively and at 3 and 12 months postoperatively to compare. Multivariate analysis was also performed to evaluate risk factors for dysphagia.
RESULTS: A total of 132 patients met the inclusion criteria, 77 of whom had undergone ACF and 55 of whom had undergone PCF. Dysphagia rates between ACF and PCF cohorts were similar at baseline (13.0% vs 18.2%, p = 0.4). New-onset dysphagia rates were also comparable at 3-month follow-up (39.7% vs 23.1%, p = 0.08) and 12-month follow-up (32.6% vs 32.4%, p > 0.99). Patients who underwent PCF had worse Neck Disability Index (NDI) scores at 3 months than did patients with ACF (13.67 ± 9.49 vs 10.55 ± 6.24, respectively; p = 0.03). There were significantly higher NDI scores for patients with dysphagia at 3 months in both the ACF and PCF groups and at 12 months for those in the PCF group. Analogously, EuroQol-5 Dimensions scores were worse for patients with dysphagia; however, this was only significant for patients in the ACF group at 3 months. There were no significant risk factors for the development of dysphagia found on multivariate analysis.
CONCLUSIONS: Similar rates and severity of dysphagia were seen following ACF and PCF at 3- and 12-month follow-up. This suggests that long-term dysphagia following cervical fusion surgery may be due to structural changes from the fusion rather than the surgical approach. However, the ACF cohort was significantly younger, and this may have partially accounted for the findings. PROs were also compared for patients with and without dysphagia, demonstrating worsened outcomes in some domains for patients who presented with dysphagia at 3- and 12-month follow-up. This suggests that dysphagia may be associated with a decreased quality of life after cervical fusion.

METHODS: Systematic Review.
OBJECTIVE: To evaluate which cervical deformity correction technique between anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) produces better clinical, radiographic, and operative outcomes.
METHODS: We conducted a meta-analysis comparing studies involving ACDF and ACCF. Adult patients with either original or previously treated cervical spine deformities were included. Two independent reviewers categorized extracted data into clinical, radiographic, and operative outcomes, including complications. Clinical assessments included patient-reported outcomes; radiographic evaluations examined C2-C7 Cobb angle, T1 slope, T1-CL, C2-7 SVA, and graft stability. Surgical measures included surgery duration, blood loss, hospital stay, and complications.
RESULTS: 26 studies (25727 patients) met inclusion criteria and were extracted. Of these, 14 studies (19077 patients) with low risk of bias were included in meta-analysis. ACDF and ACCF similarly improve clinical outcomes in terms of JOA and NDI, but ACDF is significantly better at achieving lower VAS neck scores. ACDF is also more advantageous for improving cervical lordosis and minimizing the incidence of graft complications. While there is no significant difference between approaches for most surgical complications, ACDF is favorable for reducing operative time, intraoperative blood loss, and length of hospital stay.
CONCLUSIONS: While both techniques benefit cervical deformity patients, when both techniques are feasible, ACDF may be superior with respect to VAS neck scores, cervical lordosis, graft complications and certain perioperative outcomes. Further studies are recommended to address outcome variability and refine surgical approach selection.

OBJECTIVE: To explore the feasibility of applying CT Hounsfield Units (HUs) for the assessment of preoperative paraspinal muscle fat infiltration (FI) in different segments in patients who underwent anterior cervical discectomy and fusion (ACDF). To compare the consistency of preoperative paraspinal muscle FI evaluations using MRI and those via CT HUs in patients who underwent ACDF surgery.
METHODS: Ninety-five patients (45 males and 50 females, aged 37‒71 years) who received CT and MRI examinations and underwent ACDF surgery were retrospectively analyzed. In the axial T2-weighted MR images at the median level of the C3/4, C4/5, and C5/6 segments, regions of interests (ROIs) were delineated along the boundaries of the cervical multifidus (MF) and semispinalis cervicis (Scer) muscles. Using the threshold tool in ImageJ software, areas of fat tissue and intermuscular septa within the ROI were quantified. The effective cross-sectional area (ECSA) for each side was obtained by subtracting the areas of fat tissue and intermuscular septa from the total ROI area. The ratio of the fat tissue area to the CSA was then calculated to determine the initial FI value. The depth of subcutaneous fat from the midline spinous process to the epidermis at the median plane of the C4/5 intervertebral disc was measured. The initial FI values were then divided by the depth of fat to determine the post-correction FI value. Using the Picture Archiving and Communication System (PACS), at identical segments and planes, ROIs were delineated using the same method as in MRI under a standard soft tissue window (width of 500 HU, level of 60 HU). The CT HU values were measured within these defined areas. The CT HU values from both sides are summed to obtain the total HU value for the segment. According to whether the measurement results of two sets of data follow a normal distribution, Pearson\'s test or Sperman\'s test was used to analyze the correlation.
RESULTS: On MRI, a statistically significant difference was observed in the post-correction FI only at the C3/4 segment compared to the other two segments (P < 0.05). No significant difference in the post-correction FI between the C4/5 and C5/6 segments was noted (P > 0.05). The CT HU results showed a substantial discrepancy between C3/4 and C4/5 segments and between C3/4 and C5/6 segments (P < 0.05), whereas no statistically significant difference was found in the CT HU value between the C4/5 and C5/6 segments (P > 0.05). The consistency analysis revealed a relatively strong correlation between the post-correction FI and CT HU values of the C3/4 and C4/5 segments. Furthermore, a strong correlation was detected in the variations in the measurement outcomes at the C5/6 segment.
CONCLUSIONS: Patients requiring surgical treatment for the cervical spine exhibit varying degrees of FI in paraspinal muscles across different locations and segments. Evaluating the degree of FI in the paraspinal muscles of the cervical spine through CT HU values is feasible. There is considerable consistency between the post-correction FI assessed under MRI and the measurements of CT HU values in evaluating the FI of paraspinal muscles in the cervical spine.