The pathogenesis of cervical spondylotic myelopathy (CSM) is often multifactorial. Hence, the treatment of this disease requires a differentiated surgical approach in order to adequately address the underlying pathology.
Purpose
The aim of this review is to identify factors that influence the choice of treatment strategy and to summarize them in an algorithm that serves as a decision aid in choosing the optimal indication for surgical treatment. An attempt is made to define the threshold values for the indication of surgical treatment and to discuss the ideal timing for performing surgery.
Materials and methods
On the basis of the published data, the influencing factors on the prognosis of CSM, as well as surgical approaches are discussed.
Results
Circumferential spinal cord compression, a sharply defined myelopathy signal in the T2-weighted MRI sequence, and segmental instability at the level of the myelopathy signal mean an unfavorable prognosis for the worsening of CSM. The most important factors that influence the choice of the surgical access point are the sagittal profile of the cervical spine, the extent of myelopathy, the extent of stenosis, and the location of the myelopathy-inducing pathology. Previously existing neck pain and prior cervical surgery must also be considered.
Discussion
On the basis of the research carried out, we developed an algorithm that could serve as an aid in choosing the right treatment in the setting of cervical spondylotic myelopathy.
Aim of this study is to compare late degenerative MRI changes in a subset of patients operated on with ACDF to a second subset of patients presenting indication to ACDF but never operated on.
Methods
Patients from both subgroups received surgical indication according to the same criteria. Both subgroups underwent a cervical spine MRI in 2004–2005 and 10 years later in 2015. These MRI scans were retrospectively evaluated with a cervical spine ageing scale.
Results
Comparing the two subset of patients both suffering from clinically relevant single-level disease returns no statistically significant difference in the degenerative condition of posterior ligaments, presence of degenerative spondylolisthesis, foraminal stenosis, diameter of the spinal canal, Modic alteration, and intervertebral discs degeneration at 10-year follow-up.
Conclusions
The adjacent segment degeneration represents, in the present cohort, a result of the natural history of cervical spondylosis rather than a consequence of fusion.
Correction of rigid cervical deformities often requires osteotomies to realign the spine. Cervical pedicle subtraction osteotomy can be technically challenging due to the presence of cervical nerve roots and usually can only be performed at C7 or T1 due to the presence of vertebral arteries. In contrast, anterior cervical osteotomy can be performed throughout the cervical spine and is a safe and effective method for correction of both sagittal and coronal cervical deformities. We describe the anterior cervical osteotomy technique with a review of the pertinent literature.
Methods
A step-by-step technical guide for anterior cervical osteotomy is provided with a focus on surgical nuances and complication avoidance. Two illustrative cases of fixed sagittal and coronal deformities are included to demonstrate the substantial amount of deformity correction achievable using the anterior cervical osteotomy technique.
Results
Both patients in the illustrative cases had successful clinical and radiographic outcome following deformity correction utilizing the anterior cervical osteotomy technique.
Conclusion
Anterior cervical osteotomy is a safe and effective technique for correction of rigid cervical deformities. Spine surgeons should be familiar with this technique to optimize clinical outcome in patients undergoing cervical deformity correction.
Caring for pediatric spine trauma patients places spine surgeons in situations that require unique solutions for complex problems. Recent case reports have highlighted a specific injury pattern to the lower cervical spine in very young children that is frequently associated with complete spinal cord injury.
Methods
This report describes the presentation and treatment of a C6–C7 dislocation in a 3-year-old patient with an incomplete spinal cord injury. The highly unstable cervical injury and the need to prevent neurologic decline added complexity to the case.
Results
A multi-surgeon team allowed for ample manpower to position the patient; with individuals with the requisite training and experience to safely move a patient with a highly unstable cervical spine. Initial closed reduction under close neurophysiologic monitoring, posterior fusion and immediate anterior stabilization lead to a successful patient outcome with preserved neurologic function. A traumatic cerebrospinal fluid leak, while a concern early on during the procedure, resolved without direct dural repair and did not complicate the patient’s fusion healing. Additional anterior stabilization and fusion allowed long-term stability with bone healing that may not be achievable with posterior fixation and/or soft tissue healing alone.
Conclusions
Familiarity with the challenges and solutions presented in the case may be useful to surgeons who could face a similar challenge in the future.
To present a method of posterior arch and lateral mass screw (PALMS) insertion and to prove its feasibility.
Methods
Four formalin-fixed specimens and 40 macerated atlas vertebras were used to describe the relevant anatomy. The height of the posterior arch was measured on 42 consecutive patients using standard CT of the cervical spine. The operative technique and the special CT reconstructions used for preoperative planning are described. Eight patients underwent posterior fixation using this technique.
Results
We described the relevant anatomy and important anatomical landmarks of the posterior arch of the atlas. PALMS placement was modified according to these anatomical findings. Fifteen PALMSs were placed in eight patients using this technique without vascular or neural injury.
Conclusion
It is feasible to place PALMS using the described technique. CT angiography is of crucial importance for preoperative planning using the described special reconstructions. The arch posterior to the lateral mass (APLM) is defined as the bone stock situated posterior to the lateral mass, respecting its convergence. The ideal entry point for a PALMS is on the APLM above the center of the converging lateral mass. A complete or incomplete ponticulus posticus and a retrotransverse foramen or groove can be used as an accessory landmark to refine the entry point.
Recently, strategies aimed at optimizing provider factors have been proposed, including regionalization of surgeries to higher volume centers and adoption of volume standards. With limited literature promoting the regionalization of spine surgeries, we undertook a systematic review to investigate the impact of surgeon volume on outcomes in patients undergoing spine surgery.
Methods
We performed a systematic review examining the association between surgeon volume and spine surgery outcomes. To be included in the review, the study population had to include patients undergoing a primary or revision spinal procedure. These included anterior cervical discectomy and fusion (ACDF), anterior/posterior cervical fusion, laminectomy/decompression, anterior/posterior lumbar decompression with fusion, discectomy, and spinal deformity surgery (spine arthrodesis).
Results
Studies were variable in defining surgeon volume thresholds. Higher surgeon volume was associated with a significantly lower risk of postoperative complications, a lower length of stay (LOS), lower cost of hospital stay and a lower risk of readmissions and reoperations/revisions.
Conclusions
Findings suggest a trend towards better outcomes for higher volume surgeons; however, further study needs to be carried out to define objective volume thresholds for individual spine surgeries for surgeons to use as a marker of proficiency.
The purpose of this study was to develop a simple and clinically useful morphological classification system for congenital lumbar spinal stenosis using sagittal MRI, allowing clinicians to recognize patterns of lumbar congenital stenosis quickly and be able to screen these patients for tandem cervical stenosis.
Methods
Forty-four subjects with an MRI of both the cervical and lumbar spine were included. On the lumbar spine MRI, the sagittal canal morphology was classified as one of three types: Type I normal, Type II partially narrow, Type III globally narrow. For the cervical spine, the Torg-Pavlov ratio on X-ray and the cervical spinal canal width on MRI were measured. Kruskal–Wallis analysis was done to determine if there was a relationship between the sagittal morphology of the lumbar spinal canal and the presence of cervical spinal stenosis.
Results
Subjects with a type III globally narrow lumbar spinal canal had a significantly lower cervical Torg-Pavlov ratio and smaller cervical spinal canal width than those with a type I normal lumbar spinal canal.
Conclusion
A type III lumbar spinal canal is a globally narrow canal characterized by a lack of spinal fluid around the conus. This was defined as “functional lumbar spinal stenosis” and is associated with an increased incidence of tandem cervical spinal stenosis.
Injuries to the cervical spine are immanently accompanied by trauma to the extracranial cerebral arteries.
Material and methods
A prospective cohort study was carried out from October 2013 to October 2015 including 76 patients (39 women and 37 men) with a median age of 77 years and either fractures or discoligamentary injuries who were examined with duplex sonography and/or computed tomography (CT) angiography. Additionally, approximately 80 patients with a cervical spine distorsion were evaluated using the same modalities. Statistical analyses were carried out using the program Bias 11.01.
Results
The overall incidence of traumatic dissection of the internal carotid artery was 2.5?% and in 50?% of the cases (1.2?%) with neurological symptoms. For vertebral arteries the incidence of 10.5?% was relatively high and 25?% of patients were symptomatic (2.6?%). Osteophytes and the degree of displacement were identified as the major risk factors. The vertebral canal and the skull base were regions most prone to vascular injury. In the case of distorsion of the cervical spine no vascular trauma has so far been found.
Conclusion
In cases of trauma to the cervical spine accompanying vascular injuries should also be taken into consideration. The current therapy option is anticoagulation in cases of neurologically asymptomatic patients. Patients with neurological symptoms could benefit from endovascular techniques.
Cervical spine alignment interests appeared recently and relationships between the pelvis and the cervical spine have been reported but remain unclear. In this study, postoperative changes for cranial, cervical, lumbar and sagittal balance parameters have been measured in adult scoliosis surgery without major sagittal malalignment to appreciate the adaptation of the cervical spine.
Methods
Twenty-nine consecutive patients with a surgical adult degenerative scoliosis treated with a T8–T11 to iliac fusion without PSO or multiple Ponte’s osteotomies had preoperative and postoperative full spine EOS radiographies to measure spino-pelvic parameters. Correlation analysis between the different parameters was performed.
Results
Lower cervical, lordosis, lumbar lordosis and thoracic kyphosis were increased in postoperative as no changes were observed for upper cervical lordosis. C1–C7 CL highly correlated (0.85 in preoperative and 0.87 in postoperative) with C7 slope, which highly correlated itself with global balance parameters (0.74 in preoperative and 0.71 in postoperative for CAM-PL) underlining the relationship between cervical spine alignment and global malalignment.
Conclusions
Modifications of lower CL are observed, as upper CL remains constant. If no correlation was found for LL, TK and CL changes, CL appears to be highly correlated with C7 slope, which highly correlated itself with sagittal global balance parameters. C7 slope appears as a base for CL influenced by the spine global alignment.
The cervical segmental instability often occurs simultaneously with Modic changes (MCs). However, it is unknown whether there is a relation between the two diseases. The aim of this study was to evaluate the relationship between MCs and cervical segmental instability, cervical curvature and range of motion (ROM) in the cervical spine.
Methods
A total of 464 patients with neck pain or cervical neurologic symptoms who underwent imaging examination were analyzed retrospectively. Based on MRI imaging cervical MCs were diagnosed, and patients were divided into with or without MCs groups. The cervical curvature and range of motion were measured. We compared the incidence of cervical instability, cervical curvature and ROM between the two group patients and their relationships with MCs were studied. Logistic regression was used to study the risk factors associated with MCs.
Results
MCs were observed in 94 of 464 patients and 122 of total 2320 cervical segments and were most frequent at C5–6 segment. The incidence of the cervical instability was significantly higher in patients with MCs than those without MCs at cervical level C3–7. In addition, cervical curvature and ROM in patients with MCs were less than those without MCs. Logistic regression analysis showed that the occurrence of cervical spine instability, less cervical curvature and ROM were risk factors for MCs.
Conclusions
Patients with MCs were prone to have cervical instability at the same cervical level and may have a higher possibility of less cervical curvature and ROM.
To investigate the prevalence of low virulence disc infection and its associations with characteristics of patients or discs in the cervical spine.
Background
Low virulence bacterial infections could be a possible cause of intervertebral disc degeneration and/or back pain. Controversies are continuing over whether these bacteria, predominantly Propionibacterium acnes (P. acnes), represent infection or contamination. However, the current studies mainly focus on the lumbar spine, with very limited data on the cervical spine.
Methods
Thirty-two patients (20 men and 12 women) who underwent anterior cervical fusion for degenerative cervical spondylosis or traumatic cervical cord injury were enrolled. Radiological assessments included X-ray, CT, and MRI of the cervical spine. Endplate Modic changes, intervertebral range of motion, and disc herniation type were evaluated. Disc and muscle tissues were collected under strict sterile conditions. Samples were enriched in tryptone soy broth and subcultured under anaerobic conditions, followed by identification of the resulting colonies by the PCR method.
Results
Sixty-six intervertebral discs were excised from thirty-two patients. Positive disc cultures were noted in eight patients (25%) and in nine discs (13.6%). The muscle biopsy (control) cultures were negative in 28 patients and positive in 4 patients (12.5%); three of whom had a negative disc culture. Seven discs (10.6%) were positive for coagulase-negative Staphylococci (CNS) and two discs were positive for P. acnes (3.0%). A younger patient age and the extrusion or sequestration type of disc herniation, which represented a complete annulus fibrous failure, were associated with positive disc culture.
Conclusions
Our data show that CNS is more prevalent than P. acnes in degenerative cervical discs. The infection route in cervical discs may be predominantly through an annulus fissure. Correlation between these infections and clinical symptoms is uncertain; therefore, their clinical significance needs to be investigated in the future.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
Surgical correction of severe and rigid cervical kyphosis with chin-on-chest deformity poses significant challenges to both the patient and surgeon once surgery is considered as the treatment of choice.
Objectives
This article presents the current concepts of corrective surgery for patients with severe and rigid cervical kyphosis.
Material and methods
Narrative review and report of clinical experience.
Results
The treatment of severe cervical kyphosis indicates a dedicated deformity assessment, the analysis of regional and global imbalance, the identification of spinal sagittal plane compensation mechanisms, detailed radiographic and clinical planning of corrective surgery, and the meticulous performance of surgical correction. Most recent large-scale studies serve as evidence for the benefit of surgical correction and outline the complications that need to be targeted during and after surgery.
Conclusion
Surgical correction of severe cervical kyphosis can be a pleasant and life-changing event for the disabled patient.
Facet joints are a clinically important source of chronic cervical, thoracic, and lumbar spine pain. The purpose of this study was to systematically evaluate the prevalence of facet joint pain by spinal region in patients with chronic spine pain referred to an interventional pain management practice.
Methods
Five hundred consecutive patients with chronic, non-specific spine pain were evaluated. The prevalence of facet joint pain was determined using controlled comparative local anesthetic blocks (1% lidocaine or 1% lidocaine followed by 0.25% bupivacaine), in accordance with the criteria established by the International Association for the Study of Pain (IASP). The study was performed in the United States in a non-university based ambulatory interventional pain management setting.
Results
The prevalence of facet joint pain in patients with chronic cervical spine pain was 55% 5(95% CI, 49% – 61%), with thoracic spine pain was 42% (95% CI, 30% – 53%), and in with lumbar spine pain was 31% (95% CI, 27% – 36%). The false-positive rate with single blocks with lidocaine was 63% (95% CI, 54% – 72%) in the cervical spine, 55% (95% CI, 39% – 78%) in the thoracic spine, and 27% (95% CI, 22% – 32%) in the lumbar spine.
Conclusion
This study demonstrated that in an interventional pain management setting, facet joints are clinically important spinal pain generators in a significant proportion of patients with chronic spinal pain. Because these patients typically have failed conservative management, including physical therapy, chiropractic treatment and analgesics, they may benefit from specific interventions designed to manage facet joint pain.
The cervical spine is very complex, and it allows the largest range of motion relative to the rest of the spine. The fundamental function of the cervical spine is to maintain the head balanced over the trunk and to maintain horizontal gaze. The cervical spine must be both stable and flexible to guarantee function. Changes of the sagittal profile of the cervical spine may affect function and quality of life. The relationship between full body alignment and maintaining gaze necessitates a thorough understanding of the cranio-spino-pelvic alignment as a component of balance.
Question
Now the question is, what kind of sagittal profile does the cervical spine need for proper function? In the literature, normal sagittal alignment of the cervical spine is controversial. In general, there is the assumption that the alignment is lordotic. Does the data in the literature support this?
Results
The present literature review supports the following facts: Ideal cervical spine alignment is mostly lordotic, but not always; ideal cervical spine alignment can be lordotic, neutral or kyphotic; ideal cervical spine alignment is driven by the necessity of supporting the head and maintaining horizontal gaze; the cervical spine is in harmony with regional alignment (thoracic kyphosis) and sagittal global alignment (SVA):
TK (↑)?→?T1 Slope (↑)?→?CL (↑),
TK (↓)?→?T1 Slope (↓)?→?CL (↓),
SVA >50?mm: the cervical curve should be lordotic to maintain horizontal gaze,
SVA <0?mm: the cervical curve should be kyphotic to maintain horizontal gaze.
Continued innovation in surgery requires a knowledge and understanding of historical advances with a recognition of successes and failures.
Questions/purposes
To identify these successes and failures, we selectively reviewed historical literature on cervical spine surgery with respect to the development of (1) surgical approaches, (2) management of degenerative disc disease, and (3) methods to treat segmental instability.
Methods
We performed a nonsystematic review using the keywords “cervical spine surgery” and “history” and “instrumentation” and “fusion” in combination with “anterior approach” and “posterior approach,” with no limit regarding the year of publication. Used databases were PubMed and Google Scholar. In addition, the search was extended by screening the reference list of all articles.
Results
Innovative surgical approaches allowed direct access to symptomatic areas of the cervical spine. Over the years, we observed a trend from posterior to anterior surgical techniques. Management of the degenerative spine has evolved from decompressive surgery alone to the direct removal of the cause of neural impingement. Internal fixation of actual or potential spinal instability and the associated instrumentation have continuously evolved to allow more reliable fusion. More recently, surgeons have developed the basis for nonfusion surgical techniques and implants.
Conclusions
The most important advances appear to be (1) recognition of the need to directly address the causes of symptoms, (2) proper decompression of neural structures, and (3) more reliable fusion of unstable symptomatic segments.
Surgical management of patients with multilevel CSM aims to decompress the spinal cord and restore the normal sagittal alignment. The literature lacks of high level evidences about the best surgical approach. Posterior decompression and stabilization in lordosis allows spinal cord back shift, leading to indirect decompression of the anterior spinal cord. The purpose of this study was to investigate the efficacy of posterior decompression and stabilization in lordosis for multilevel CSM.
Methods
36 out of 40 patients were clinically assessed at a mean follow-up of 5, 7 years. Outcome measures included EMS, mJOA Score, NDI and SF-12. Patients were asked whether surgery met their expectations and if they would undergo the same surgery again. Bone graft fusion, instrumental failure and cervical curvature were evaluated. Spinal cord back shift was measured and correlation with EMS and mJOA score recovery rate was analyzed.
Results
All scores showed a significative improvement (p < 0.001), except the SF12-MCS (p > 0.05). Ninety percent of patients would undergo the same surgery again. There was no deterioration of the cervical alignment, posterior grafted bones had completely fused and there were no instrument failures. The mean spinal cord back shift was 3.9 mm (range 2.5–4.5 mm). EMS and mJOA recovery rates were significantly correlated with the postoperative posterior cord migration (P < 0.05).
Conclusions
Posterior decompression and stabilization in lordosis is a valuable procedure for patients affected by multilevel CSM, leading to significant clinical improvement thanks to the spinal cord back shift. Postoperative lordotic alignment of the cervical spine is a key factor for successful treatment.
To review relevant data for the management of esophageal perforation after anterior cervical surgery.
Methods
A case of delayed esophageal perforation after anterior cervical surgery has been presented and the relevant literature between 1958 and 2014 was reviewed. A total of 57 papers regarding esophageal perforation following anterior cervical surgery were found and utilized in this review.
Results
The treatment options for esophageal perforation after anterior cervical surgery were discussed and a novel management algorithm was proposed.
Conclusion
Following anterior cervical surgery, patients should be closely followed up in the postoperative period for risk of esophageal perforation. Development of symptoms like dysphagia, pneumonia, fever, odynophagia, hoarseness, weight loss, and breathing difficulty in patients with a history of previous anterior cervical surgery should alert us for a possible esophageal injury. Review of the literature revealed that conservative treatment is advocated for early and small esophageal perforations. Surgical treatment may be considered for large esophageal defects.
Even though internal fixation has expanded the indications for cervical spine surgery, it carries the risks of fracture or migration, with associated potential life threatening complications. Removal of metal work from the cervical spine is required in case of failure of internal fixation, but it can become challenging, especially when a great amount of scar tissue is present because of previous surgery and radiotherapy.
Case presentation
We report a 16 year old competitive basketball athlete who underwent a combined anterior and posterior approach for resection of an osteosarcoma of the sixth cervical vertebra. Fourteen years after the index procedure, the patient eliminated spontaneously one screw through the intestinal tract via an oesophageal perforation and developed a severe dysphagia. Three revision surgeries were performed to remove the anterior plate because of the great amount of post-surgery and post-irradiation fibrosis.
Conclusions
Screw migration and oesophageal perforation after cervical spine surgery are uncommon potentially life-threatening occurrences. Revision surgery may be challenging and it requires special skills.
Although many reports are available on using a variety of instruments and techniques to prevent wrong-level spine surgery, the accurate localization of the correct spinal level remains problematic. At the same time, surgeons are also required to reduce radiation exposure to patients and operating room personnel. To solve these problems, we developed and used specially designed marking devices with a unique three-dimensional structure.
Purpose
To evaluate the accuracy of our novel devices for localization of the spinal level to prevent wrong-level surgery and reduce the amount and time of radiation exposure during surgery.
Study design
This was a retrospective cohort study.
Methods
In 8240 consecutive patients who underwent microendoscopic spine surgery between 1993 and 2012, the incidence of wrong-level surgery was studied. In addition, the amount of radiation exposure and total fluoroscopy time were measured in recent 100 consecutive patients using a digital dosimeter attached to the fluoroscope.
Results
Eight (0.097 %) patients had undergone wrong-level surgery. The average radiation exposure was 0.26 mGy (range 0.10–1.15 mGy), and the average total fluoroscopy time was 3.1 s (range 1–7 s).
Conclusions
Our novel localization devices and technique for their use in spine surgery are reliable and accurate for identifying the target level and contributed to reductions in preoperative localization error and radiation exposure to patients and operating room personnel.
