Alignment Of Cervical Spine Research Articles

Does the positioning of the patient in the EOS machine affect the validity of cervical and head parameters calculated on whole-spine radiographs?

The aim was to study the validity of free-standing position using modifiers for assessing cervical spine alignment. A total of 26 asymptomatic subjects (45 ± 11years) and 13 with spinal deformities (30 ± 21years) underwent lateral radiographs using EOS®, while adopting 3 different positions, in 2 sequences, without mirror and then with mirror (m) placed in front of them: first, the neutral standing position (upper extremities positioned on the sides of the body, P1 and P1m), then free-standing (P2 and P2m) and modified free-standing (P3 and P3m) positions (shoulders flexed at 90° and fingers placed on clavicles then cheeks, respectively). Participants were asked not to move their trunk and shoulders when moving from P1 to P2 and then P3. Eighteen cervical radiographic parameters were calculated from the 6 radiographs. The effects of shoulder flexion, mirror placement, and finger positioning on cervical alignment were studied using a repeated-measures ANCOVA. Mirror placement had no effect on cervical alignment. Concerning the effect of shoulder flexion, C2-C7 and T1 slopes were significantly decreased in P2 and P2m (C2-C7 = 10° and 8°; T1 slope = 26° and 24°, respectively) and P3 and P3m (C2-C7 = 9° and 9°; T1 slope = 25° and 26°, respectively) compared to P1 and P1m (C2-C7 = 14°and 14°; T1 slope = 29°and 30°, respectively), without exceeding the uncertainty level. Assessment of cervical alignment is valid on whole-spine radiographs when the shoulders are flexed (free-standing position). Clear instructions regarding the shoulder position at 90°, without moving the trunk, neck, and head before placing the fingers on the clavicles or cheeks, can ensure a cervical alignment comparable to that obtained with the neutral position, which is considered the most physiological one.

Influence of the type of atlantoaxial dislocation secondary to os odontoideum on sagittal alignment and balance of the subaxial cervical spine after posterior atlantoaxial fusion.

This retrospective study aims to investigate the effect of the type of atlantoaxial dislocation due to os odontoideum on the sagittal alignment and balance of the cervical spine after posterior atlantoaxial fusion. Data of 48 consecutive patients who underwent posterior C1-C2 fusion to treat atlantoaxial dislocation/instability due to os odontoideum were retrospectively reviewed. Radiographic variables, namely the T1 slope (T1S), C1-C2 angle, C2-C7 angle, C1-C2 sagittal vertical axis (SVA), C2-C7 SVA, and modified atlas-dens interval (MADI), were measured preoperatively, immediate postoperatively, and at final follow-up. Patients were divided into three groups based on the preoperative MADI. Differences within and between groups in radiographic variables and relationships between the investigated variables were analyzed. The MADI was correlated with the preoperative to postoperative changes in the C1-C2 angle (r = 0.776, P < 0.05) and C2-C7 angle (r = -0.357, P < 0.05). In the group with anterior atlantoaxial dislocation, the C1-C2 angle and C2-C7 SVA were significantly enlarged at final follow-up (P < 0.05), while the C2-C7 angle was significantly reduced (P < 0.05). The changes in C1-C2 angle and C2-C7 angle were opposite between the posterior group and the anterior dislocation group. The direction/type of atlantoaxial subluxation correlates with the changes in lower cervical curvature after atlantoaxial fusion. Patients with atlantoaxial posterior dislocation and atlantoaxial instability are less likely than those with atlantoaxial anterior dislocation to develop loss of lordosis after posterior atlantoaxial fusion.

Altered body balance and plantar pressure distribution in young adults with forward head posture

BackgroundForward head posture (FHP), a common postural issue, affects balance and may be linked to altered muscle activity and cervical spine alignment. This study investigated the impact of FHP on static balance and plantar pressure distribution in adults. We hypothesized that FHP would be associated with poorer balance and altered pressure distribution. MethodsThis case-control study investigated the impact of FHP on static balance and plantar pressure distribution in adults (n = 52). Participants were categorized based on craniovertebral angle (CVA), into FHP (CVA <47°) and control (CVA ≥47°) groups. Static balance was assessed using a NeuroCom® Balance Manager System, evaluating parameters like center of gravity sway and directional control. Plantar pressure distribution was measured with an Emed Pedobarography system during walking, analyzing maximum force, peak pressure, and contact area. ResultsParticipants with FHP showed poorer balance with eyes closed on foam compared to the control group. Additionally, the FHP group exhibited lower total maximum force and altered force distribution in both feet during walking. Correlations suggested that higher CVA degrees were associated with decreased balance and altered plantar pressure distribution. Despite, linear regression analyses revealed no significant predictive relationships between CVA and specific balance measures, it showed significant associations with several plantar pressure distribution parameters, including total maximum force exerted on both feet, maximum force on the forefoot, and peak pressure on the hindfoot. ConclusionThese findings suggest that FHP may influence balance and plantar pressure distribution, with a potentially stronger effect on plantar pressure than balance parameters.

Incidence of Cervical Kyphosis and Factors Associated with Improvement in Postoperative Cervical Spinal Alignment in Idiopathic Scoliosis with Major Thoracolumbar/Lumbar and Thoracic Curves.

Background: This study aimed to compare the incidence and severity of cervical kyphosis before and after surgery between patients with adolescent idiopathic scoliosis (AIS) with major thoracolumbar/lumbar curves (Lenke type 5C group) and those with major thoracic curves (Lenke type 1A group). Further, factors associated with cervical spinal alignment changes after surgery in the two groups were examined. Methods: This study included consecutive patients with AIS who underwent posterior spinal fusion for Lenke type 1A and 5C curves and who were followed up for at least 1 year. To measure changes in sagittal alignment, all patients underwent radiography before, immediately after, and at 1 year after surgery. The correlation coefficients change the value of the C2-C7 angle before and after surgery (ΔC2-ΔC7) and other spinopelvic parameters were examined. Results: In total, 19 of 30 patients in the Lenke type 1A group and 21 of 36 in the Lenke type 5C group presented with cervical kyphosis preoperatively. Hence, the incidence of cervical kyphosis did not significantly differ between the two groups. Further, the two groups had significantly higher thoracic kyphosis (TK) and greater C2-C7 angles postoperatively. The TK of the Lenke type 5C group further increased at 1 year postoperatively. The Lenke 1A type group presented with a significant re-decrease in the C2-C7 angle at 1 year postoperatively. However, the C2-C7 angle of the Lenke type 5C group did not change. The ΔTK was closely associated with the ΔC2-ΔC7 in the Lenke type 1A group, but not in the Lenke type 5C group. Conclusions: In thoracic AIS, postoperative cervical alignment should achieve an adequate TK and promote correction of the coronal plane curve. Moreover, selective corrective surgery can improve postoperative cervical alignment in lumbar AIS.

Effects of intraoperative hinge fracture on postoperative cervical spine alignment in double door cervical laminoplasty

Introduction Hinge fracture and cervical kyphosis are known complications of cervical laminoplasty. Prior literatures on hinge fracture focused mainly on laminoplasty performed using the open-door technique. In this study we aim to assess the effect of intraoperative hinge fracture on postoperative cervical spine alignment in cervical laminoplasty performed using the double door technique. Methods This study recruited patients who received double door cervical laminoplasty from January 2014 to December 2022. The diagnosis, demographic data, preoperation and postoperation cervical spine alignment of the patients with intraoperative hinge fracture were compared with patients withouintraoperative hinge fracture. Cervical spine alignment was measured using C2–7 Cobb's angle on neutral lateral cervical spine X ray. Results Nine patients with intraoperative hinge fracture and 51 patients without intraoperative hinge fracture were recruited into the study. There was no statistically significant difference in age, sex, diagnosis and preoperative cervical spine alignment between the patients with and without intraoperative hinge fracture. Significant difference was found in the postoperation cervical spine alignment (1.9 ± 15.5° vs 9.7 ± 13.6°, p = .044) and change in cervical spine alignment (−12.9 ± 12.1° vs −4.0 ± 10.0, p = .02) between patients with and without intraoperative hinge fracture. Conclusions In double door cervical laminoplasty, intraoperative hinge fracture is associated with development of postoperative cervical kyphosis.

Cervical Spine Alignment; Observation Over a Ten-Year Period Using Measurement of Cobb Angle and a Modified Pfirrmann Grade

Background and Aim: We sought to explore whether or not this excessive use of smart technology may be associated with a generational change in the cervical spine over time. Methods and Results: All those patients who underwent cervical spine MRI aged 15 to 30 years over the years June 2007 to 2008 and June 2017 to 2018 were considered for evaluation. Each patient had measurement of their Cobb angle and a modified Pfirrmann grade. 217 patients - 83 (2007-2008) and 134 (2017-2018) were evaluated. There was no difference in cervical alignment over time, but males tended to have a greater lordosis(p&lt;0.001). Using the modified Pfirrmann grading system a difference over time was noted most noticeable at C2/3 (p=0.004); C3/4 (p=0.019 and C7/8 (p=0.003). Conclusion: There was no change in the structural integrity of the cervical spine between the two groups over time. A worsening degenerative disease without a structural change was observed, an effect was more apparent in the males.

A Comparative Study on the Effects of Three Types of Pillows on Head-neck Pressure Distribution and Cervical Spine Alignment

A Comparative Study on the Effects of Three Types of Pillows on Head-neck Pressure Distribution and Cervical Spine Alignment

Comparing Spinal Cord Drift, Clinical Outcomes and C5 Palsy in Degenerative Cervical Myelopathy: A Study of Cervical Laminoplasty Versus Laminectomy/Fusion.

Retrospective comparative study. (i)to compare spinal cord drift between laminectomy and fusion(LF) and cervical laminoplasty(LP) for degenerative cervical myelopathy(DCM) treatment,(ii)to study relationship between preoperative cervical alignment, postoperative spinal cord drift, functional outcome, and C5 palsy. A cohort of 114 patients who underwent LP or LF for DCM were identified. After propensity-score matching, both groups included 30 patients each.Cobb angle(C2-C7) was used to assess pre-and postoperative cervical spine alignment(at 2-year follow-up).Based on alignment, there were lordotic(L) and straight(S) subgroups.Spinal cord position was measured on sagittal-and axial-T2W MRI of cervical spine pre-and postoperatively at 2-year follow-up and cord drift was measured by subtracting preoperative values from postoperative values.Functional recovery(mJOA score, mJOA recovery rate),and C5 palsy in patients were recorded and compared. LF had higher mean spinal cord drift than LP(2.66 ± .77 vs 2.16 ± .80mm, P = .049).Lordotic subgroups exhibited greater cord drift than straight subgroups within LP and LF groups.Both groups significantly improved mJOA scores at 2-year follow-up, with no LP-LF difference in mJOA recovery rate(mJOA-RR).Lordotic subgroups had significantly higher mJOA-RR(LP-L vs LP-S,P = .048; LF-L vs LF-S,P = .045).Preoperative cervical alignment, cord drift, and mJOA-RR correlated well(Spearman's ρ .7143 and .6053 respectively).Patients with >2.5mm cord drift(n = 24) had significantly higher mJOA-RR as compared to <2.5mm cord drift(n = 18). Substantial clinical difference was seen in C5 palsy risk between LP-S and LF-L, with the LF-L group having 3-fold higher risk. LF had a biomechanical advantage in maximizing spinal cord drift in severe DCM cases, while both LP and LF showed significant improvements in neurological function. However, variability in C5 palsy rates highlights the need for individualized patient assessment.

Current Concepts of Cervical Spine Alignment, Sagittal Deformity, and Cervical Spine Surgery.

There are not many reports on cervical spine alignment, and only a few analyze ideal surgical approaches and optimal amounts of correction needed for the various types of deformity. We comprehensively reviewed the present literature on cervical spinal deformities (with or without myelopathy) and their surgical management to provide a framework for surgical planning. A general assessment of the parameters actually in use and correlations between cervical and thoracolumbar spine alignment are provided. We also analyzed posterior, anterior, and combined cervical surgical approaches and indications for the associated techniques of laminoplasty, laminectomy and fusion, and anterior cervical discectomy and fusion. Finally, on the basis of the NDI, SF-36, VAS, and mJOA questionnaires, we fully evaluated the outcomes and measures of postoperative health-related quality of life. We found the need for additional prospective studies to further enhance our understanding of the importance of cervical alignment when assessing and treating cervical deformities with or without myelopathy. Future studies need to focus on correlations between cervical alignment parameters, disability scores, and myelopathy outcomes. Through this comprehensive literature review, we offer guidance on practical and important points of surgical technique, cervical alignment, and goals surgeons can meet to improve symptoms in all patients.

Fatty infiltration and morphology of cervical muscles in patients with temporomandibular disorders: A case-control study.

Changes in the fatty infiltration and/or muscle volume of neck muscles can alter cervical spine alignment and cranial load distribution, which may cause pain in the orofacial region. The aim of the study was to examine the muscle volume and fatty infiltration of neck muscles in patients with temporomandibular disorders (TMD). This case-control study included 18 patients with TMD and 18 ageand sex-matched controls. The muscle volume and fatty infiltration of the neck muscles of the participants were measured using magnetic resonance imaging (MRI) and ITK-SNAP software. The 3D models of the sternocleidomastoid (SCM), splenius capitis (SPLC), semispinalis cervicis (SC)-semispinalis capitis (SCP), and multifidus (M) muscles within the C3-C7 range were created using ITK-SNAP, a semi-automatic segmentation software. The models were used to determine the volumes and fatty infiltration levels. The Neck Disability Index (NDI) was used to assess neck pain-related disability. The severity of TMD was determined using the Fonseca Anamnestic Index (FAI), while jaw-related disability was measured with the Jaw Functional Limitation Scale-20 (JFLS-20). Pain levels were recorded at rest and during chewing using the numeric rating scale (NRS). There were no statistically significant differences in total muscle volume, fatty infiltration volume and fatty infiltration percentage of the SCM, SPLC, SCP, SC, and M muscles between the 2 groups (p > 0.05). The patient group had higher NDI scores compared to the controls (p < 0.001). The NDI scores correlated positively with the JFLS-20 (r = 0.831, p < 0.001), FAI (r = 0.815, p < 0.001) and NRS scores at rest (r = 0.753, p < 0.001) and during chewing (r = 0.686, p < 0.001). The present study did not identify any significant differences in the neck muscle volume or fatty infiltration between the TMD patients and controls. However, the severity of neck disability was found to correlate with jaw function, pain and TMD levels.

Upper and lower cervical alignment parameters measured on supine magnetic resonance imaging with the occipital slope as a key marker of cervical alignment.

Cervical spine alignment is evaluated by measuring the cervical angles or parameters on standing plain radiography. In this study, we aimed to evaluate mainly the upper cervical alignment and the correlation between upper and lower cervical sagittal parameters measured on supine magnetic resonance imaging (MRI). Cervical MRIs of 210 outpatients were reviewed to measure the upper and lower cervical sagittal parameters. Their mean values were compared with normative values measured on standing X-ray from the literature. Correlations between the parameters were analyzed using the Pearson's correlation coefficient. The C0 slope was correlated with all other parameters, except for the C2-7 sagittal vertical axis. The strongest correlations (r > 0.500) were between the CL and C2 slope, between the CO2 and C0 slope, and between the C2 slope and C0 slope. On supine MRI, the C0 slope is a key marker of cervical spinal alignment. A strong correlation was observed between the C2 slope and C0 slope; therefore, the relationship between upper and lower cervical alignment could be assessed using slopes on MRI.

Optimizing Surgical Strategy for Cervical Spinal Deformity: Global Alignment and Surgical Targets.

Cervical spinal deformity (CSD) is a complex condition characterized by abnormal curvature and cervical spine alignment. It can lead to a multitude of symptoms, including chronic pain, neurological deficits, and functional impairments, severely impacting an individual's health-related quality of life (HRQoL). Surgical intervention is often necessary to address the deformity and alleviate symptoms, but optimal surgical strategies remain a topic of ongoing research and debate. This narrative review aims to provide an in-depth overview of the surgical management of CSD, focusing on optimizing patient outcomes and enhancing readers' understanding of the complexities involved. We begin by discussing the importance of preoperative assessment, including comprehensive radiographic evaluation and careful consideration of the global spinal alignment. The relationship between the cervical spine and the reciprocal changes that occur are explored to guide surgeons in their decision-making process. Furthermore, we delve into the selection of fusion levels, emphasizing the significance of identifying the primary driver of deformity. We review the current literature on optimal alignment targets and strategies to optimize surgical planning. By providing a comprehensive analysis of the surgical management of CSD, this review aims to enhance the readers' knowledge and assist surgeons in making informed decisions when planning and executing surgical interventions. Understanding the intricacies of CSD correction and the latest advancements in the field can ultimately improve patient outcomes and enhance HRQoL for individuals suffering from this challenging condition.

A novel classification that defines the normal cervical spine: an analysis based on 632 asymptomatic Chinese volunteers

PurposeThe “normal” cervical spine may be non-lordotic shapes and the cervical spine alignment targets are less well established. So, the study was to propose novel classification for cervical spine morphologies with Chinese asymptomatic subjects, and to address cervical balance status based on the classification.MethodAn overall 632 asymptomatic individuals on cervical spine were selected from January 2020 to December 2022, with six age groups from 20–30 year to 70 plus group. Cervical alignment contained C2-7 cervical lordosis (C2-7 CL) and T1 slope (T1S), together with C1-2 CL, C2-4 CL, C5-7 CL, C2S, cervical sagittal vertical axis (CSVA), thoracic inlet angle (TIA) and neck tilt (NT). C2-7 cervical lordosis was regarded as primary outcomes. To identify groups with similar cervical alignment parameters, a 2-step cluster analysis was performed.ResultsC2-7 CL, T1S, CSVA, TIA and NT increased by age and mean value of them were larger in male than female group. Four unique clusters of female lordotic cluster, female kyphotic cluster, male lordotic cluster and male kyphotic cluster were classified mainly based on gender and C2-C7 CL. T1S was the independent influencing factor for C2-7 CL in all individuals and C2-7 CL = -28.65 + 0.57 × TIA, which varied from clusters. Although interactions among cervical parameters, it showed the alignment was more coordinated in lordotic groups.ConclusionsThe cervical sagittal profile varied with age and gender. Four clusters were naturally classified based on C2-7 CL and gender. The cervical balance status was addressed by C2-7 CL = − 28.65 + 0.57 × TIA.

Surgical strategies for the treatment of deformity-associated cervical spondylotic stretch myelopathy: a case series with technically nuanced illustrative operative videos.

The aim of this study was to elucidate the vital role of anterior-only osteotomies for rigid cervical kyphosis causing stretch myelopathy by using illustrative cases and high-definition intraoperative videos. The authors describe 4 select patients who underwent anterior-only osteotomies within a 2-year time frame and demonstrate the nuances of each case with unique operative videos. Outcomes for each of the cases demonstrated marked improvement in cervical spine alignment relative to preoperative conditions. Postoperative CT scans and upright radiographs for case 1 at 8 months demonstrated complete reduction of the kyphotic deformity and restoration of the C2 slope. In case 2, the 2-year postoperative radiographs showed significant realignment of the cervical spine, and the patient made significant neurological improvement since the operation, specifically in hand dexterity, balance, neck pain, and the ability to comfortably achieve and maintain a horizontal gaze. For case 3, postoperative upright radiographs revealed marked improvement in the patient's cervical sagittal alignment. The 4-month follow-up was also notable for substantial improvement in postural neck pain, bilateral upper extremity strength, and continued improvements in dexterity. Case 4 also demonstrated an excellent outcome with unkinking of the patient's spinal cord and correction of her sagittal plane deformity, as shown on her 5-month postoperative upright radiographs. Deformity-associated cervical spondylotic stretch myelopathy often leads to devastating neurological decline and can significantly decrease quality of life. Carefully selected cases of circumferentially rigid cervical kyphosis can be successfully corrected with anterior-only osteotomies followed by posterior fixation while avoiding back-front-back operations.

Transarticular Fixation Using Bioabsorptive Screws for Cervical Lesions.

Transarticular screw fixation is a method for posterior cervical fixation. It is ergonomic because neither connectors nor rods are needed. Biomechanical studies have shown that its fixation force is not inferior to that of lateral mass screws. More information is needed on the surgical outcome of procedures using bioabsorptive screws. We investigated the long-term surgical and radiological outcomes of posterior cervical decompression and fusion using bioabsorptive screws for transarticular fixation.Of 10 patients who underwent cervical spine transarticular fixation using bioabsorptive screws, nine presented with cervical degenerative spondylosis and one with a traumatic cervical spine injury. The mean postoperative follow-up period was 57.1 months. Transarticular screw fixation was successful in all 10 patients; no intraoperative complications were encountered. Bilateral screw breakage was discovered in a patient with cervical spine instability and associated dystonia due to cerebral palsy; there was no symptom deterioration, facet joint breakage, or instability exacerbation. Facet fusion was obtained in the nine other patients. At the patients' last visit, their clinical symptoms were significantly improved. Whole cervical spine alignment (-4.21 ± 7.2 to -5.2 ± 8.7) and the fused segment angle (mean, -0.1 ± 9.9 to -1.2 ± 13.7) did not significantly worsen postoperatively (mean: -0.1 ± 9.9 to -1.2 ± 13.7). Transarticular fixation using bioabsorptive screws is safe and associated with good long-term outcomes. In patients with exacerbation of local instability after posterior decompression, additional transarticular fixation using bioabsorbable screws is a treatment option.

Comparison of three methods for measuring C0-1 angles and C0-2 angles

BackgroundThe mutual compensatory relationship between the upper cervical sagittal alignment and the lower cervical sagittal alignment has been repeatedly reported. However, the evaluation of the upper cervical sagittal parameters are varied in previous studies. This retrospective study was performed to compare three methods for measuring the upper cervical sagittal parameters.MethodsA total of 263 individuals with standing neutral lateral cervical radiographs were included in this study. The Frankfort horizontal line (FHL), foramen magnum line (FML), and McGregor line (ML) were separately used as the reference lines for measuring the C0-1 angle and C0-2 angle. Intraclass correlation (ICC) values were used to compare the consistency and repeatability of the three methods. Pearson’s correlation analysis was used to analyze the correlation between the sagittal parameters of the upper and lower cervical spine.ResultsThe interobserver and intraobserver ICC values obtained from using the ML to measure the C0-1 angle and C0-2 angle were both higher than those obtained from using the FML or FHL. The C0-1 angle and C0-2 angle measured by the three methods were negatively correlated with the C2-7 angle. The upper sagittal parameters measured by the FHL were the most correlated with the C2-7 angle. The correlation between the C0-1 angle measured by the three methods and the C0-2 angle measured with the FHL or ML and the C2-7 angle increased with aging.ConclusionUse of the ML to measure the C0-1 angle and C0-2 angle has higher reliability. Use of the FHL to measure the sagittal alignment of the upper cervical spine is more suitable for evaluating the compensation mechanism between the upper and the lower cervical spine.

Clinical and imaging outcomes of self-locking stand-alone cages and anterior cage-with-plate in three-level anterior cervical discectomy and fusion: a retrospective comparative study

BackgroundAnterior cervical discectomy and fusion has been considered standard management for cervical myelopathy and radiculopathy. However, the option of using self-locking stand-alone cages or cage-with-plate in three-level anterior cervical discectomy and fusion still remains controversial. The aim of this study was to evaluate the clinical and imaging outcomes of the two procedures in multilevel anterior cervical discectomy and fusion.MethodsSixty-seven patients who underwent three-level anterior cervical discectomy and fusion were enrolled in this study, of which 31 patients underwent surgery using self-locking stand-alone cages (group cage) and 36 patients using cage-with-plate (group plate). For the evaluation of clinical outcomes, modified Japanese Orthopedic Association scores, visual analogue scale for neck pain, neck disability index, Odom’s criteria and dysphagia status were measured. Imaging outcomes were evaluated by cervical sagittal angle, fusion segmental Cobb’s angle, fusion segmental height, range of motion, cage subsidence rate, fusion rate and adjacent segment degeneration. Statistical analyses were performed using the SPSS software (version 19.0).ResultsBoth groups showed improvement in modified Japanese Orthopedic Association scores, visual analogue scale for neck pain and neck disability index, after surgery, and there was no significant difference between the groups. The occurrence rate of dysphagia is significantly lower in the group cage compared with the group plate (p < 0.05). The postoperative cervical sagittal angle, fusion segmental Cobb’s angle, fusion segmental height and cage subsidence rate in the group plate were significantly superior to that in the group cage (p < 0.05). However, the rate of adjacent segment degeneration was significantly lower in the group cage compared with the group plate (p < 0.05). Both groups showed no significant difference in terms of fusion rate (p > 0.05).ConclusionsThe self-locking stand-alone cages are effective, reliable and safe in anterior cervical discectomy and fusion for the treatment of cervical myelopathy and radiculopathy. Self-locking stand-alone cages showed a significantly lower rate of dysphagia and adjacent segment degeneration, while anterior cervical cage-with-plate could provide stronger postoperative stability and maintain better cervical spine alignment.

Update of the Natural History, Pathophysiology, and Treatment Strategies of Degenerative Cervical Myelopathy: A Narrative Review.

Cervical myelopathy is a clinical syndrome resulting in symptoms of neurologic deficits due to prolonged spinal cord compression or ischemia in the cervical spine. Spinal cord compression can be caused by ossification of the posterior longitudinal ligament and hypertrophy of ligamentun flavum in addition to degenerative cervical spondylosis, degenerative disc disease, and progressive cervical kyphosis. Degenerative cervical myelopathy (DCM) is a series of disease entities caused by spinal cord compression by various nontraumatic and non-infectious causes. The pathophysiology of DCM includes spinal cord structure and function abnormalities caused by both static and dynamic factors. Surgical decompression for patients with moderate to severe cervical myelopathy not only inhibits the progression of neurological deterioration, but also improves functional status, pain, and quality of life. However, the role of nonsurgical treatment in patients with mild spinal cord compression is controversial. In general, patients with cervical myelopathies who do not undergo surgery have a poor prognosis. Appropriate surgical treatment is recommended when spinal cord compression is confirmed on image study in patients with reasonable symptoms of cervical myelopathy. The patient's overall health, degree of compression, presence of concurrent cervical radiculopathy, and cervical spine alignment, in addition to lesion location and etiology, should be considered when determining an appropriate surgical procedure. This review covers the updated issues, including pathophysiology, clinical manifestations, differential diagnosis, and available treatments for DCM.

Change in Line of Sight after Corrective Surgery of Adult Spinal Deformity Patients: A 2-Year Follow-up.

Cohort study. There is currently no published study that focuses on the spinal corrective surgery effects with cranial parameters in adult spinal deformity (ASD) patients. It is an important factor to measure since it plays a critical role in maintaining the line of sight. The objective is to determine the change in cranial parameters using the slope of McGregor's line (McGS) after ASD surgery after 2 years of follow-up. A study concluded that cervical spine alignment (C2-C7 lordosis) is strongly affected by thoracic kyphosis (TK). Another study showed that patients with ascending gaze had significantly more thoracolumbar malalignment. This retrospective study includes 295 corrective surgery patients with ASD. Subjects were divided into two groups after propensity age matching analysis: cranial malalignment (McGS <-8 or >13) and normal cranial alignment (-8≤ McGS ≤13). Lumbar lordosis (LL), pelvic tilt (PT), TK, cervical lordosis (CL), and sagittal vertical axis (SVA) were evaluated between the two groups. SVA (95-56 mm) and PT (34°-25°) decreased and LL (19°-41°) increased 2 years after surgery (p <0.05), but McGS (-1.1° to -0.5°) and CL (21°-19°) did not change. Conversely, in the group with cranial malalignment, SVA (120-64 mm), PT (35°-26°), and LL (12°-41°) showed similar results to the normal cranial parameter group 2 years after surgery, but in contrast, McGS (-13° to -2°) and CL (24°-18°) improved significantly. Severe ASD adversely affects to maintain horizontal gaze but can be improved by spinal corrective surgery.

Comparative Study of Anterior Transvertebral Foraminotomy and Anterior Cervical Discectomy and Fusion for Unilateral Cervical Spondylotic Radiculopathy

To study the compared surgical and radiographic outcomes of Transvertebral foraminotomy (TVF) with anterior cervical discectomy and fusion (ACDF) in patients with unilateral cervical spondylotic radiculopathy (CSR). We performed a retrospective comparative study of 72 consecutive patients with 1- or 2-level CSR treated with ACDF or TVF. 27 patients who underwent TVF (group T) and 45 patients who underwent ACDF (group A) with a minimum 2-year follow-up were enrolled. We evaluated clinical outcomes and radiological assessment. Clinical outcome included Visual analog scale (VAS) scores for axial, arm pain at preoperatively and final follow-up. VAS score for painful swallowing was also evaluated 1week after surgery. Radiological assessment included C2-7 sagittal Cobb angle (C2-7 CA), range of motion (ROM) of C2-7 CA, the height, angle and ROM of the functional spinal unit (FSU), and tip of the spinous process of the operated segment. We also evaluated the disc height, FSU angle, and ROM of the FSU at the cranial adjacent segment. Both groups had good clinical outcomes. Soft tissue swelling was significantly less prominent in group T than that for group A. VAS scores for painful swallowing is lower in group T without significant difference. The ROM of C2-7 CA, FSU, and spinous processes demonstrated a significant reduction in group A compared with group T.(P < 0.05). Disc height at the cranial adjacent segment was maintained in group T. TVF is as effective as ACDF for unilateral CSR and preserves whole cervical spine and segmental alignment.