Degenerative Cervical Spine Research Articles

Cervical intervertebral disc denervation during rotator cuff tendon plasty

Objective. To analyze the effect of denervation of intervertebral discs in the cervical spine on the results of surgical treatment of patients with injuries to rotator cuff tendons of the shoulder joint.Material and Methods. Study design: descriptive hypothesis-generating study. The study included patients requiring surgical treatment of rotator cuff tear. Two groups were identified: Group A included 28 patients who underwent plastic repair of rotator cuff tear with additional denervation of intervertebral discs, and Group B – 30 patients who underwent only plastic surgery for rotator cuff tear. The intensity of pain according to the VAS, functional activity due to neck pain (NDI), functionality of the shoulder joint (UCLA), and the degree of intervertebral disc degeneration according to MRI were assessed, and the effectiveness of treatment was determined. Statistical calculations were performed using the RStudio program.Results. In the group of patients with denervation of intervertebral discs, a more pronounced decrease in the intensity of pain syndrome at 3, 6, and 12 months (p < 0.001; p < 0.001; and p = 0.002), a more proportion of effectively treated patients at 3 months (p = 0.003), and significant increase in functional activity according to NDI at 3, 6 and 12 months of follow-up period (p < 0.001; p = 0.010; and p = 0.045) were observed.Conclusions. There is an underestimation of the role of degenerative cervical spine pathology in the occurrence of shoulder joint pain. In the case of rotation cuff plasty the additional denervation reduces the intensity of pain syndrome in the shoulder joint in the postoperative period.

Morphologic Changes in the Vertebral Artery Subsequent to Cervical Spine Degeneration and Aging: Analyses by Computed Tomography Angiography Using Multiplanar and 3-Dimensional Reconstructions

To identify the morphologic changes in the vertebral artery (VA) subsequent to cervical spine degeneration and aging and to investigate the risk factors for iatrogenic VA injury or occlusion. Eighty-eight consecutive patients (176 bilateral VAs) were retrospectively analyzed using radiographs, computed tomography, and computed tomography angiography images. The Kellgren and Lawrence (KL) score and its modified subscores were used to grade the severity of degenerative changes in the cervical spine. VA tortuosity widths and diameters were measured between the C2 and C6 transverse foramens. The outcome measures were statistically analyzed for difference, correlation, and explanatory variable. The level with a high prevalence of VA stenosis was also evaluated. There were significant positive correlations between the KL score and VA tortuosity width, and between age and VA tortuosity width. Osteophyte formation in the facet joint was the predominant explanatory variable for medial deviation of the VA. Significant positive correlations were evident between the dominant VA diameter and KL score or age. VA stenosis occurred at C3/C4 (24.5%) with the highest prevalence and it was caused by uncovertebral joint osteophytes (52.0%) with the highest incidence. The present study provides important evidence for decisions of surgical strategy and for avoiding catastrophic VA injury or occlusion in cervical spine surgeries.

Causes of same-route reoperations in degenerative cervical spine disease after a primary anterior approach

Introduction : An anterior approach is most commonly used in procedures performed in cases of degenerative cervical spine disease (DCSD). Although generally considered safe, they are not free of complications that may result in the need for reoperation. The aim of the study is to analyse causes of reoperation via the same approach for DCSD in patients who have previously undergone one of the anterior cervical approaches. Materials and methods : Of the 2,794 patients managed with a surgical procedure performed from an anterior approach, a total of 38 were reoperated on via the same anterior route between year 2004–2019 at a single tertiary centre. Retrospective assessment was conducted based on medical records and radiological imaging. Subjects were grouped into 2 categories: early revision surgeries (within 90 days of the 1st procedure) and late revision surgeries (after 90 days). Results : The incidence of same-route reoperation was 1.36%. Late reoperations were over twice as frequent as early ones (n = 26 vs n = 12). The main cause for reoperation in the late group was adjacent segment disease (ASD; n = 25, 96.15%) whereas in the early group, persistent stenosis and implant dislocation were equally prevalent (each n = 3, 27.3%). The reoperations which were conducted earliest were due to emergent post-operative prevertebral hematomas (n = 2, 16.67%). Conclusion : The risk of needing a same-route reoperation after anterior approaches in DCSD is relatively low with late revisions being more prevalent. Adjacent segment disease is the most common cause. Implant dislocation as well as persistent spinal canal stenosis are the main causes behind early revisions.

Results of Four-Level Anterior Cervical Discectomy and Fusion Using Stand-Alone Interbody Titanium Cages.

Study DesignThis is a retrospective study with a minimum follow-up of 2 years.PurposeThe aim of this study is to assess the long-term outcomes after performing the four-level anterior cervical discectomy and fusion (ACDF) in the treatment of degenerative cervical spine disease using stand-alone titanium cages.Overview of LiteratureOver the last decades, a rapid increase in the use of stand-alone cages for ACDF has been observed. However, research on their application in the treatment of four-level diseases is insufficient.MethodsIn this study, 130 patients presenting with symptomatic cervical spondylosis who underwent four-level ACDF using stand-alone cages in our institution between 2008 and 2016 were assessed. Fifty-two patients were women and 78 men with a mean age of 60.5 years. Their clinical and radiological outcomes were assessed. The results of the Neck Disability Index (NDI) and Visual Analog Scale as well as bony fusion were evaluated, and the revisions were analyzed. All of the patients underwent the four-level microscopic ACDF using the same titanium rectangular cage.ResultsThe mean follow-up was 47±11.4 months. A fusion of all four levels was achieved in 80.72% of the patients. In 25 patients (19.23%), an incomplete bony bridging was observed in at least one fusion level at the final follow-up. However, only two patients (1.5%) were symptomatic and underwent revision. The mean NDI improved significantly from 39.4±9.3 at presentation to 8.3±6.6 at the final follow-up. Cervical lordosis improved significantly from a mean of 5.5° preoperatively to a mean of 15° postoperatively. Cage sinking and loss of segment height during healing had a mean of 3 mm.ConclusionsOverall, the application of four-level ACDF using titanium cages in a stand-alone technique has been proven to be a safe and effective treatment method for degenerative disease. In a large cohort, a high rate of good long-term clinical and radiological results was achieved.

Occurrence, Risk Factors, and Time Trends for Late Reoperations due to Degenerative Cervical Spine Disease: A Finnish National Register Study of 19 377 Patients Operated on Between 1999 and 2015.

BACKGROUNDSurgery for degenerative cervical spine disease has escalated since the 1990s. Fusion has become the mainstay of surgery despite concerns regarding adjacent segment degeneration. The patient-specific trends in reoperations have not been studied previously.OBJECTIVETo analyze the occurrence, risk factors, and trends in reoperations in a long-term follow-up of all the patients operated for degenerative cervical spine disease in Finland between 1999 and 2015.METHODSThe patients were retrospectively identified from the Hospital Discharge Registry. Reoperations were traced individually; only reoperations occurring >365 d after the primary operation were included. Time trends in reoperations and the risk factors were analyzed by regression analysis.RESULTSOf the 19 377 identified patients, 9.2% underwent a late reoperation at a median of 3.6 yr after the primary operation. The annual risk of reoperation was 2.4% at 2 yr, 6.6% at 5 yr, 11.1% at 10 yr, and 14.2% at 15 yr. Seventy-five percent of the late reoperations occurred within 6.5 yr of the primary operation. Foraminal stenosis, the anterior cervical decompression and fusion (ACDF) technique, male gender, weak opiate use, and young age were the most important risk factors for reoperation. There was no increase in the risk of reoperations over the follow-up period.CONCLUSIONThe risk of reoperation was stable between 1999 and 2015. The reoperation risk was highest during the first 6 postoperative years and then declined. Patients with foraminal stenosis had the highest risk of reoperation, especially when ACDF was performed.

Preoperative and Postoperative Opioid Dependence in Patients Undergoing Anterior Cervical Diskectomy and Fusion for Degenerative Spinal Disorders.

Anterior cervical diskectomy and fusion (ACDF) is a procedure for effectively relieving radiculopathy. Opioids are commonly overprescribed in postsurgical settings and prescriptions vary widely among providers. We identify trends in opioid dependence before and after ACDF. We used the Truven Health MarketScan data to identify adult patients undergoing ACDF for degenerative cervical spine conditions between 2009 and 2015. Patients were segregated in four cohorts of preoperative and postoperative opioid nondependence (ND) or dependence (D) with 15 months of postoperative follow-up. A total of 25,403 patients with median age of 52 years (18-92) who underwent ACDF met the inclusion criteria. Breakdown of the four cohorts was as follows: prior nondependent who remain nondependent (NDND): 62.76% (n = 15,944); prior nondependent who become dependent (NDD): 4.6% (n = 1,168); prior dependent who become nondependent (DND): 14.03% (n = 3,564); and prior dependent who remain dependent (DD): 18.61% (n = 4,727). Opioid dependence decreased 9.43% postoperatively. Overall payments and 30-day readmissions increased 1.96 and 1.79 times for opioid dependent versus nondependent cohorts, respectively. Adjusted payments at 3 to 15 months were significantly increased for dependent cohorts with 3.56-fold increase for the DD cohort when compared with the NDND cohort. Length of stay, complications, medication refills, outpatient measures, and hospital admissions were also higher in those groups with postoperative opioid dependence when compared with those who were not opioid dependent. Opioid dependence after ACDF is associated with increased hospital readmissions, complication rates at 30 days, and payments within 3 months and 3 to 15 months postdischarge. Overall opioid dependence was decreased after ACDF procedure, however, a smaller number of opioid-dependent and opioid-naive patients became dependent postoperatively and should be followed carefully.

Long-term clinical and radiological outcomes of anterior uncoforaminotomy for unilateral single-level cervical radiculopathy: retrospective cohort study

BACKGROUND CONTEXTAnterior cervical discectomy and fusion is a common procedure for degenerative cervical radiculopathy. In 1996, Dr. H.D. Jho reported an operative technique allowing nerve root decompression via anterior uncoforaminotomy whereas avoiding fusion. PURPOSETo assess long-term clinical and radiological outcomes of anterior uncoforaminotomy in patients with degenerative cervical spine pathology. STUDY DESIGNA single clinic, retrospective cohort study. PATIENT SAMPLEAdult patients who underwent anterior uncoforaminotomy from 2013 to 2018. OUTCOME MEASURESClinical outcomes were assessed using VAS, NDI, SF-36 criteria. Radiological parameters included sagittal balance, disc height and White anPanjabi criterion. MATERIALS AND METHODSAll patients underwent unilateral single-level anterior uncoforaminotomy, and long-term clinical and radiologic follow up was carried out. Clinical outcomes were assessed using VAS, NDI, SF-36 criteria. Radiological parameters evaluated included sagittal balance, disc height and White and Panjabi criteria (3.5 mm of translation, 11 degrees of kyphosis). The mean follow-up period was 33.3 ± 10.6 months (range 12–57 months). RESULTSAll measures of clinical outcome improved. VAS (neck) and VAS (arm) decreased 3 [2; 4] and 5 [3; 5.2] points (median [interquartile range]), respectively (p<0.001); NDI improved from 0.38 [0.36; 0.4], to 0.29 [0.22; 0.34] (p<0.001). Two patients (6%) required additional surgery one year after operation. There were no complications in the perioperative period. Disc height decreased 0.8 mm [0.1; 2.1] (p<0.001). All patients retained stability of the cervical spine based on White and Panjabi criteria. Sagittal balance parameters did not change significantly. CONCLUSIONUncoforaminotomy is an effective and safe method to decompress a unilateral single-level nerve root in degenerative cervical radiculopathy whereas preserving anatomy and motion of the cervical spine.

An Unusual Pattern of Premature Cervical Spine Degeneration in STAT3-LOF.

Loss of function mutations in STAT3 (STAT3-LOF; autosomal dominant hyper-IgE (Job's) syndrome) are associated with a variety of musculoskeletal manifestations, including scoliosis, osteoporosis, and minimal trauma fractures. This retrospective magnetic resonance (MR) imaging study sought to characterize an unusual pattern of cervical spine degeneration among a cohort of STAT3-LOF patients. Cervical spine MR images of the STAT3-LOF cohort (n = 38) were assessed for a variety of degenerative changes and compared to age-matched groups of controls (n = 42) without known immune or musculoskeletal abnormalities. A unique pattern of premature cervical spine degeneration was identified among the STAT3-LOF cohort which included straightening and eventual reversal of the normal cervical lordosis, mainly due to multi-level spondylolisthesis, as well as early development of spinal canal narrowing, cord compression, and myelomalacia. Cervical spine degeneration in the STAT3-LOF cohort was significantly worse than controls in both the 30-45 and 45 + age groups. Moderate to severe degenerative changes were present after age 30, and markedly worsened over time in several cases. Bone mineral density (BMD) had a moderate negative correlation with cervical degeneration severity and a strong negative correlation with age among STAT3-LOF participants. Cervical degeneration in STAT3-LOF appears to be progressive and could result in cord compromise if left unaddressed. Focused history and physical examination for signs of neurologic compromise as well as periodic MR imaging are thus recommended for the evaluation of premature cervical spine degeneration in STAT3-LOF patients after age 30 so that timely surgical interventions may be considered to prevent spinal cord damage and permanent neurological deficits.

Radiological Assessment of the Effects of Anterior Cervical Discectomy and Fusion on Distraction of the Posterior Ligamentum Flavum in Patients with Degenerative Cervical Spines.

BackgroundThis study aimed to assess the effects of anterior cervical discectomy and fusion (ACDF) on distraction of the posterior ligamentum flavum (LF) by increasing the intervertebral disc height and positioning a graft in patients with degenerative cervical spine disease.MethodsSixty-eight patients with degenerative cervical diseases who underwent single-level ACDF were included in the analysis. The intervertebral disc height, Cobb angle, and transverse thickness of the LF were measured, and magnetic resonance imaging was performed both preoperatively and 6 weeks postoperatively on each patient. Correlation analyses were performed to evaluate the relationships between age, sex, change in intervertebral disc height, Cobb angle, and position of the intervertebral implant according to the postoperative change in LF thickness. The position of the intervertebral implant was categorized as anterior, middle, or posterior. We also evaluated radiological effects according to the implant position.ResultsThe mean intervertebral disc height increased from 5.88 mm preoperatively to 7.49 mm postoperatively. The Cobb angle was 0.88° preoperatively and 1.43° postoperatively. Age (p = 0.551), sex (p = 0.348), position of cage (p = 0.312), pre- and postoperative intervertebral disc height (p = 0.850, p = 0.900), Cobb angle (p = 0.977, p = 0.460), and LF thickness (p = 0.060, p = 1.00) were not related to changes in postoperative LF thickness. Postoperative increase in disc height was related to Cobb angle (r = 0.351, p = 0.038). No other factors were significantly related. The position of the cage was not related with the change of Cobb angle (p = 0.91), LF thickness (p = 0.31), or disc height (p = 0.54).ConclusionsChange in the intervertebral disc height and the position of the intervertebral implant after ACDF did not affect the thickness of the LF after surgery in patients with degenerative cervical spine disease.

Clinical outcome following multisegmental cervical spinal fixation in patients who recovered partially following injury

Objective:The clinical outcome following multilevel stabilization in patients who suffered cervical spinal injury and developed severe neurological deficits and then gradually partially recovered is evaluated. The basis of the surgical concept was that cervical spinal degeneration is a result of single or multilevel spinal instability and that spinal trauma exaggerates the instability.Materials and Methods:During the period 2015–2020, 14 patients who suffered severe cervical spinal injury and could be included in the classification of spinal cord injury without computed tomography evidence of trauma were surgically treated. There were 11 males and 3 females. The ages ranged from 45 to 67 years, average being 53 years. Cervical canal stenoses related to degenerative spinal changes were observed in all patients. All patients suffered severe neurological deficits and within few days or weeks had shown significant but incomplete neurological recovery. The identification of the levels of unstable spinal segments was done on the basis of radiological and clinical parameters and direct observation of spinal instability in adjoining spinal segments. Transarticular fixation was done by Camille's transarticular fixation technique. Using ASIA score, modified JOA score, and Goel Clinical Grading Scale, the clinical course of the patients was monitored.Results:All patients showed recovery in the neurological status. Recovery started in the immediate postoperative period and the improvement progressed during the period of follow-up.Conclusions:Surgery for spinal stabilization can be indicated even in cases that improve in the neurological function.

Anterior Cervical Corpectomy and Fusion for Degenerative and Traumatic Spine Disorders, Single-Center Experience of a Case Series of 119 Patients.

BACKGROUNDAnterior cervical corpectomy and fusion (ACCF) is a treatment option for several cervical pathologies. Various graft materials such as autografts, titanium mesh cages (TMC), or poly-ether-ether-ketone (PEEK) cages are used. Additional posterior fixation (PF) to provide extra support and improve stability is sometimes performed initially, or later as supplementary treatment.OBJECTIVETo describe our retrospective study of 119 consecutive cases of ACCF with synthetic grafts, in 3 cohorts of cervical spondylotic myelopathy (CSM), infectious and neoplastic processes, and trauma, with special focus on need for supplementary PF.METHODSA total of 135 adult patients treated with ACCF between January 2005 and January 2018 were identified. Patients lost to follow-up were excluded, and 119 remaining patients were included for retrospective clinical and radiological assessment.RESULTSSynthetic grafts were used in 116 (97%) cases. Only 9 (8%) ACCF cases required later supplementary PF, where 7 (78%) cases were multilevel. There was a statistically significant difference in revision rate with PF for single-level compared to multilevel ACCFs (P = .001). Revision rates with PF were 2%, 29%, and 7% in CSM, infectious and neoplastic processes, and trauma cohorts, respectively.CONCLUSIONThe results indicate that ACCF is a safe and effective treatment for degenerative and traumatic cervical spine disorders, with low complication and revision rates. Single-level ACCF can be performed without additional PF. Multilevel ACCF (n > 2) and pathologies affecting bone quality seem to be risk factors for material subsidence and instability. In these cases, additional PF should be considered.

Cervical Hemilaminectomy in the Management of Degenerative Cervical Spine Myelopathy

Introduction: Hemilaminectomy is one of the surgical options for managing cervical spondylotic myelopathy. However, it has not gained the expected popularity. This paper aims to review the utilization of hemilaminectomy, the outcome, and complications observed among patients managed with the procedure for advanced multilevel degenerative cervical myelopathy. Methods: Retrospective longitudinal analysis was done at a neurosurgical hospital in Enugu, Nigeria, between years 2010 and 2019. The Study analyzed 46 patients that had cervical hemilaminectomy for multilevel degenerative cervical myelopathy. Excluded from the study were patients offered cervical hemilaminectomy for other indications including tumor and trauma. Patients were assessed by comparing preoperative, and follow-up modified Japanese Orthopedic Association (mJOA) score and Cobb lordotic angles. The minimum postoperative follow-up period was for 1 year. Results: The mean age was 61 (43–88) years; male-to-female ratio was 3.6:1. Symptoms duration ranged from 6 months to 10 years, and 31 (67.4%) patients had significant comorbidities. The average operation time was 2 h 36 min (0.5–3.0 h). The mean blood loss was 260 mL (100–800 mL). Right hemilaminectomy was done for 37 (80.4%) patients. The average preoperative and postoperative Cobb lordotic angles were 10.90° ± 2.4° and 9.98° ± 2.1°. The mean preoperative mJOA was 8.2 ± 1.4. On follow-up 1 year after surgery, the mean mJOA score was 12.2 ± 1.1 (P = 0.0001). The neurological recovery rate at 1-year follow-up was 50.5%. One patient each experienced a transient postoperative drop in neurology, postoperative respiratory distress, and surgical site infection. Conclusion: Cervical hemilaminectomy for multilevel degenerative cervical spine myelopathy has the potential to achieve clinically satisfactory neurological improvement without significantly compromising stability and other serious long-term complications.

The risk and time trends for reoperations after surgery for degenerative cervical spine disease between 1999 and 2015 in Finland

The risk and time trends for reoperations after surgery for degenerative cervical spine disease between 1999 and 2015 in Finland

An algorithmic posterior approach to the treatment of multilevel degenerative cervical spine disease: A multicenter prospective study

An algorithmic posterior approach to the treatment of multilevel degenerative cervical spine disease: A multicenter prospective study

The beneficial effect of physiotherapy on the cervical spine mobility of ACDF patients and healthy individuals: An original observational cohort comparison research protocol

PurposePopulation aging and certain behaviors associated with modern life are contributing factors for the increasing incidence of degenerative cervical spine conditions (DCSC), and the number of cervical spine surgeries every year is. Our aim was to determine, with an original research protocol, the impact of ACDF and physiotherapy on the range of motion and EMG parameters of patients suffering from DCSC. Patients and MethodsTwo comparable subgroups of 29 patients each were recruited for the present investigation. The first cohort was composed of ACDF patients, whereas the second cohort was composed by healthy subjects. Inclinometry/Range of Motion (RoM) analyses of the neck, and cervical muscles electromyography (EMG) were used to evaluate the neck mobility. We investigated the effects of physiotherapy on ROM and EMG results in order to identify possible significant differences between healthy subjects and ACDF patients. ResultsA total of 58 patients were included in the final cohort. Extensive statistical analysis disclosed that higher NDI values were associated with a reduction of the Extension and Rotation movements, NDI scores, were found to be negatively associated to EMG voltages for Rotation, independently of the physiotherapy performed either. Extension, Lateral Bending, and Rotation showed significant improvement after just one session of physiotherapy, whereas Flexion and Extension proved to be those that contributed most to the overall neck mobility. ConclusionThe cervical spine fusion contributes to an overall reduction of cervical mobility. This data is confirmed by inclinometer and EMG parameters. Physiotherapy increases neck mobility thus possibly improving the clinical status of patients.

Analysis of the Variables Affecting the Incidence, Location, and Severity of Cage Subsidence Following Anterior Cervical Discectomy and Fusion Operation.

For surgical management of degenerative cervical spine disease with myeloradiculopathy, stand-alone cages are frequently used in 1- and 2-level anterior cervical discectomy and fusion (ACDF) operations with a paucity of literature on factors influencing cage subsidence. The aim of this study was to analyze the variables affecting the incidence, location, and severity of cage subsidence. Retrospective review of prospectively collected data of 77 patients (95 levels) undergoing ACDF surgery was conducted. Variables analyzed were age, gender, sagittal alignment, maximum disc height (superior, inferior, and procedure levels), cage size, shape, location, degree of subsidence (minor <2 mm, mild 2-4 mm, moderate 5-7.5 mm, severe >7.5 mm) and location of subsidence. The incidence of cage subsidence was 34% (32 levels), and 91% were minor or mild. Significantly lower mean maximum height of the inferior disc compared to the nonsubsidence group (5.17 versus 5.96; P = 0.0025) was recorded. Significantly greater incidence of subsidence (40%) was recorded in patients with abnormal cervical spine alignment (focal or diffuse kyphosis) versus 18% with normal alignment (P = 0.02). Greater incidence of subsidence was recorded with more anterior positioned cages (52%; p=0.01). No statistical significance was found for age, gender, superior disc height, or cage shape/size. Greater incidence of cage subsidence is significantly associated with a lower maximum disc height of the disc below the operated level (<5.5 mm), abnormal sagittal alignment, and more anteriorly positioned cages. We found that the vast majority of cage subsidence was focal, minor to mild, without having any immediate or late clinical implications in terms of need for revision surgery.

Outcome of Osteophytes After Only-Fixation as Treatment for Multilevel Cervical Spondylosis–A Minimum of 12 Months Follow-Up

This report analyzes the significance of osteophytes in the overall pathologic scheme in patients with single-level or multilevel cervical spinal degeneration. From January 2010 to December 2018, 249 patients with cervical spondylosis were surgically treated. The alterations in ventral compression caused by disc bulges, osteophytes, and ligament buckling (disc-osteophye-ligament [DOL] complex) at single or multiple levels were evaluated after surgical treatment that involved only spinal fixation and did not involve any kind of bone or soft tissue decompression. Delayed (≥1 year after surgery) postoperative imaging was available in 165 patients and these patients formed the study group. Forty-five patients underwent facet distraction arthrodesis (group A), 106 patients underwent only-fixation involving transarticular screw insertion (group B), and 14 patients underwent hybrid fixation that involved both intra-articular spacers and transarticular fixation techniques (group C) as the surgical treatment. The size of the DOL complex at the segments that underwent fixation was reduced in 136 patients. The size of the DOL complex or its related dural or neural compression did not increase in any of the cases evaluated. Reduction in the size of DOL was more pronounced in patients in group A in both immediate postoperative and delayed images and in patients in group C at spinal levels at which facet distraction was performed using facet distraction spacers. Spinal stabilization reduces the size of osteophytes. Facet distraction spacers are more effective in reduction of the size of DOL in both immediate and delayed postoperative periods.

Biomechanics of the effect of subaxial cervical spine degeneration on atlantoaxial complex in idiopathic retro-odontoid pseudotumor development

ObjectivesRetro-odontoid pseudotumor (ROP), with no rheumatoid arthritis, atlantoaxial instability, or other primary diseases, is defined as idiopathic retro-odontoid pseudotumor (IROP). Cervical spine degeneration is associated with IROP development. This study aims to evaluate the effect of cervical spine degeneration on the atlantoaxial complex and find the possible biomechanical mechanism of IROP development. MethodsThis study was performed using a three-dimensional (3D) finite element (FE) analysis. A degenerated FE model (FEM) and five operation FEMs (C1-C2 fusion, C0-C2 fusion, C0-C3 fusion, C0-C4 fusion, and C1 posterior arch resection) were established based on a normal 3D FEM of the cervical spine including C0-T1 with the main ligaments and muscles. The parameters, including the C1-C2 range of motions (ROMs) and odontoid-related ligaments’ stresses in degenerated and operation FEMs, were obtained and compared with those in normal FEM. ResultsCompared to normal FEM, degenerated FEM had reduced C3-C7 ROMs and increased C1-C2 ROMs and odontoid-related ligaments’ stresses. After internal fixation, C1-C2 ROMs and most odontoid-related ligaments’ stresses were greatly decreased, but with no significant differences among C0-C2, C0-C3, C0-C4, and C1-C2 fusion models. For the C1 posterior arch resection model, C1-C2 ROMs and most odontoid-related ligaments’ stresses increased, compared with normal FEM. ConclusionsCervical spine degeneration plays an important part in IROP development in biomechanics. Atlantoaxial complex compensates for cervical spine degeneration, with increased C1-C2 ROMs and odontoid-related ligaments’ stresses. Atlantoaxial fusion or short segmental occipitocervical fusion can effectively reduce the stress and should be considered in IROP treatment.

Cervical Extensor Muscles Play the Role on Malalignment of Cervical Spine: A Case Control Study With Surface Electromyography Assessment.

A case control study. The aim of this study was to identify the potential impact of cervical spine malalignment on muscle parameters. Muscular factors are associated with cervical alignment. Nevertheless, only muscle dimensions or imaging changes have been evaluated, function of cervical muscles has scarcely been investigated. Thirty-four patients diagnosed as cervical spine degeneration associated with cervical malalignment and 32 control subjects were included in this case control study. Visual analogue scale (VAS) and the neck disability index (NDI) were used. The sagittal alignment parameters and cervical range of motion (ROM) were measured on cervical spine lateral radiographs, included C2-C7 lordosis, C2-C7 sagittal vertical axis (C2-C7 SVA), cervical gravity-sagittal vertical axis (CG-SVA), T1-Slope, and spinal canal angle (SCA). Surface electromyography (SEMG)-based flexion-relaxation ratio (FRR) was measured. The result showed VAS score of the neck significantly lower in controls (P<0.05), C2-C7 lordosis, C2-C7 SVA, CG-SVA, T1-Slope and ROM showed significantly different (P<0.001) between malalignment group and control group, FRR of splenius capitis (FRRSpl) and upper trapezius (FRRUTr) of the malalignment group were lower than in the control group, which correlated well with NDI (rSpl = -0.181 rUTr = -0.275), FRRSpl correlated well with VAS (rSpl = -0.177). FRRSpl correlated strongly with C2-C7 SVA (r = 0.30), CG-SVA (r = 0.32), T1-Slope (r = 0.17), ROM (r = 0.19), FRRUTr correlated with C2-C7 lordosis (r = -0.23), CG-SVA (r = 0.19), T1-Slope (r = 0.28), ROM (r = 0.23). Cervical malalignment patients had more tensional posterior cervical muscle and poor muscle functions. CG-SVA showed advantages in evaluating cervical malalignment.Level of Evidence: 3.

Intraoperative Neuromonitoring Use Patterns in Degenerative, Nondeformity Cervical Spine Surgery: A Survey of the Cervical Spine Research Society.

A cross-sectional survey study. To determine the neuromonitoring (NM) usage patterns among cervical spine surgeons when performing degenerative, nondeformity cervical spine surgery. Intraoperative NM is frequently used in spine surgery. Although there is literature to support the use of NM in deformity surgery, its utility in degenerative cervical spine surgery remains unclear. A survey was distributed to members of the Cervical Spine Research Society to assess practice patterns of NM use during degenerative cervical spine surgery. The survey consisted of 17 multiple choice questions. The first 3 questions focus on practice experience. The remaining 14 questions pertain to NM practice patterns in the setting of radiculopathy and myelopathy. Significantly more surgeons routinely (>75% of the time) used NM for myelopathy versus radiculopathy (64% vs. 38%, P<0.001). Private practitioners were overall more likely to use NM than academicians (55% vs. 28%, P=0.007 for radiculopathy; 75% vs. 57%, P=0.09 for myelopathy). No significant difference in NM usage was found comparing neurosurgeons and orthopedic spine surgeons. The most commonly cited primary reasons for NM usage were prevention of positioning/hypotension-related neurological complications, and medicolegal protection. Routine NM use during degenerative cervical surgery is significantly more common in myelopathy and is thought to be of more value than in radiculopathy. However, the most common reasons for usage were to provide medicolegal cover and to mitigate neurological complications related to positioning/hypotension, rather than to protect against direct surgical events. These findings contrast the prevailing notion that NM is beneficial in reducing complications related to events occurring in the surgical site when performing spinal deformity correction. We believe that these data provide an important baseline for informing best practice guidelines and further study regarding appropriate NM use for degenerative, nondeformity, cervical spine surgery.