Subaxial Cervical Injury Research Articles

Functional outcomes in unstable complete subaxial cervical spinal injuries with respiratory paralysis and/or hemodynamic instability

IntroductionSubaxial cervical spine injuries (SCSI) can lead to disastrous consequences such as quadriplegia, with/without respiratory paralysis (RP) and hemodynamic instability (HDI). Till date, there is no literature available for reporting outcomes of SCSI patients specifically pertaining to those presenting with RP/HDI and ours is the first study to document the same. MethodsRetrospective 6-year study from a tertiary trauma centre database including patients >/= 18 years of operated SCSI. Only patients with ASIA A grade with admission RP/HDI and unstable injuries (fractures, subluxations) were included. Patients with ASIA grade B and above, patients with non-osseous injuries (such as disc herniation, central cord syndrome etc.) were excluded. Results24 cases were analysed. C5 and C6 levels were the commonest. Vertebral listhesis/subluxation was the predominant radiological finding. The mean age was 47.4 years (22–79 years) and all, except one were males. Fall from height and road traffic accident (RTA) were the most common mechanisms of injury. The most common surgery was anterior discectomy and fusion followed by corpectomy. The overall mortality rate was 22/24 (92)%. Cord edema and hemorrhage had significant association with survival. None of the grade A survivors with HDI/RP showed improvement. The mean FU duration was 18.5 months (range, 16.5–20.5 months). ConclusionsSubaxial ASIA A cervical spine injuries with pre-operative RP/HDI is an indicator for non-improvement. This is the first study documenting outcome in such patients. The mortality rate in these patients is very high and is an extremely poor prognostic factor for recovery. Hence, surgery in such patients need to be decided judiciously, especially in developing countries that has a significant financial impact on the family members.

Results Of Anterior Fixation for Subaxial Cervical Injuries in A Tertiary Care Centre

Sub-axial injuries of cervical spine involving posterior ligaments, articular facets and pillars are communal, and surgical treatment is debatable, and studies describe variable consequences from combined access of anterior and posterior approach or separately Objective: To assess the outcome of early (<72 hours) anterior cervical discectomy and fusion with plating for injuries of the sub-axial cervical spine. Methods: A retrospective analysis, from January 2018 to December 2020 was conducted in a tertiary care referral center. 110 patients (67 male, 43 females; mean age 51.1 years; range 19-80 years) who endured anterior cervical discectomy (ACD) at single-level and fusion (ACDF using a polyetheretherketone, (PEEK, cage) with plate fixation for injuries of sub-axial cervical spine were evaluated. Radiological evaluation was done considering fusion, segmental height (SH), advancement of adjacent segment disease (ASD) and lordosis (Cobb Angle). Clinical results were evaluated by means of visual analogue scale (VAS) for neck pain and Frankel Grading for neurological function Results: The cervical trauma was instigated by road traffic accident (RTA) in 69 cases, slip down in 16 cases and a fall from a height in 25 cases. Simple lateral cervical X-rays and CT with reconstruction were taken in all subjects and showed dislocation or subluxation of C3 to C4 in 15 patients, 39 patients with C4 to C5 dislocation, 32 patients with C5 to C6 dislocation and C6 to C7 in 24 patients. The preoperative mean Cobb angle was -3.9 ± 8.01 °. 4.1 ± 6.6 ° was the mean Cobb angle instantly later to treatment and 1.8 ± 4.7 ° at the final visit. The operation brings a substantial decrease in the regional kyphotic angle (p <0.05). The SH mean before surgery was 37.01 ± 1.9 mm. The SH mean was 41.2 ± 1.9 mm instantly after operation and 37.9 ± 1.9 mm at the final visit. The mean rise in height at the end of observation was 0.9 mm. The variance between pre-operative SH measurements and final SH was significant (p <0.05). An improvement of VAS from 8.4±1.01 to 2.8±1.6 at 12 months was statistically significant. There was also an improvement in 19.1% of cases for at least one Frenkel grade at 12 months follow-up. Conclusions: The fusion with a PEEK cage and the fixation with anterior cervical plate resulted in satisfactory clinical results and high fusion rates deprived of any morbidity at the donor-site. This procedure is effective and safe for single-level sub-axial injuries of the cervical spine

Surgical Results of Sub-Axial Cervical Injury in Adult Patients Treated Via Anterior Approach

Objectives: To determine the results of treatment of sub-axial cervical injury in adults using open reduction, anterior approach and injury stabilization <72 hours. Place and Duration: In the Neurosurgery department of Pakistan Institute of Medical Sciences, Islamabad for one-year duration from January 2021 to December 2021. Methods: 82 total patients diagnosed with history of traumatic sub-axial injury using MRI and anteroposterior and x-rays lateral and anteroposterior views were selected. ASIA Impairment Scale was applied for valuation, which was completed at admission and 6-months later. Results: The patients mean age in this analysis was 39.20± 5.11 years. Conferring to the ASIA scale, 2 grades enhancement were realised in 24 cases and 54 cases have one grade improvement. Death occurred in 4 cases, 2 were linked to accompanying trauma, one was associated with the complication of the surgery, and the remaining 1 death were related to complications like aspiration. The results were good in 58 (74.5%) of 78 cases and satisfactory in 20 (25.5%). Conclusions: Anterior Cervical Discectomy and Fusion (ACDF) in this study showed good results and considered reliable option of treatment for improved stabilization of the spine anatomically with primary reduction. Keywords: Anterior approach, sub-axial cervical injury and ASIA (American Spinal Injury Association) scoring.

A multilevel noncontiguous spinal fracture with cervical and thoracic spinal cord injury.

Introduction and importanceA multi-level non-contiguous spinal fracture (MNSF) caused by a high-energy impact is a type of complex traumatic injury that is been frequently initially missed, and resulting in delayed diagnosis which adversely affects can result in spinal deformity and neurological deficit. This report describes the operative management of a patient with MNSF with spinal cord injury involving the cervical and thoracic vertebrae by cervical orthosis and posterior thoracic decompression and fusion.Case presentationAn 18-year-old male presented with extensive neck pain and paraplegia (ASIA A), following a motor vehicle accident. Radiographic imaging revealed MNSF: a non-displaced spinous process fracture of C5 (AO Spine subaxial cervical injury classification A0) with spinal cord injury combined with fracture-dislocation of T5 to T9 (AO Spine thoracolumbar injury classification C3). Posterior thoracic decompression and fusion was performed at T3 to T8. After the patient underwent the thoracic spine and cervical orthosis treatment, He received rehabilitation program and training transfer with wheelchair without caregiver. His sitting and balance were significantly improved at the 6 months follow-up. Although the lower extremity functions (ASIA A) may not improve due to the severe spinal cord injury.Clinical discussionMNSF with spinal cord injury following a high-velocity accident is an unstable and complex injury. Important of the clinical assessment and according to the injuries the treatment may vary.ConclusionsCervical orthosis was alternative treatment to preserve cervical motion treatment and posterior thoracic decompression with fixation is an effective option for patients in this MNSF with spinal cord injury.

Оцінка рівня нестабільності ушкоджень, класифікованих за AOSpine Subaxial Cervical Spine Injury Classification System

Актуальність. При визначенні спрямованості та обсягу хірургічного лікування у хворих із травматичним ушкодженням шийного відділу на субаксіальному рівні основними є такі критерії: характер і ступінь ушкодження остеолігаментозного апарату шийного відділу хребта, що визначає рівень нестабільності; ступінь компресії структур хребетного каналу; стан сагітального профілю. Метою цієї роботи є оцінка ступеня нестабільності різних типів ушкоджень шийного відділу хребта, класифікованих відповідно до AOSpine Subaxial Cervical Spine Injury Classification System. Матеріали та методи. Проведено ретроспективний аналіз даних спондилограм, комп’ютерних і магнітно-резонансних томограм 168 пацієнтів із травматичним ушкодженням шийного відділу хребта на субаксіальному рівні, які перебували на стаціонарному лікуванні у відділенні патології спинного мозку ДУ «Інститут нейрохірургії ім. акад. А.П. Ромоданова НАМН України» в період з 2008 по 2018 р. Виконувалася кількісна оцінка ступеня нестабільності із застосуванням Cervical Spine Injury Severity Score і визначення типу ушкодження згідно з AOSpine Subaxial Cervical Spine Injury Classification System. Результати. Виявлено, що медіана показника нестабільності прогресивно наростає зі збільшенням ступеня тяжкості типу ушкодження. Найбільш широкий діапазон значень показника рівня нестабільності відзначається при компресійному типі ушкоджень: від 6 балів (95% довірчий інтервал (ДІ) 4,76–6,84) при типі А1 до 11 балів (95% ДІ 9,48–11,81) при А4. Для типів А2 і А3 зареєстровано 7 балів (95% ДІ 6,68–7,53) і 8 балів (95% ДІ 7,97–9,01) відповідно. Флексійно-екстензійні ушкодження характеризуються меншим діапазоном значень. Медіана прогресивно зростає від типу В1 — 13 балів (95% ДІ 12,4–13,92) до B3 — 15,5 бала (95% ДІ 14,5–16,35). Показник для В2 займає проміжне значення і становить 15 (95% ДІ 13,59–15,52). Максимальні значення при згинально-розгинальних ушкодженнях — 18 балів, зареєстровані як при типі В2, так і В3. Тип С демонструє найбільший рівень нестабільності — 17 балів (95% ДІ 16,58–17,86) та досить широкий діапазон розрахованих значень — від 13 до 20 балів. Висновки. Загальною тенденцією є збільшення рівня нестабільності в низці підтипів від А1 до С, проте навіть ушкодження типу А1 за певних умов виявляються досить нестабільними і вимагають хірургічного втручання. На противагу класичним уявленням ушкодження типу А досить часто супроводжуються ураженням фасеткових суглобів, що також необхідно враховувати при визначенні індивідуальної тактики терапії постраждалих.

Quality of Life in Adult Patients Receiving Cervical Fusion for Fresh Subaxial Cervical Injury: The Role of Associated Spinal Cord Injury.

Purpose To study postoperative Health-Related Quality of Life (HRQOL) after instrumented fusion for fresh subaxial cervical trauma and the effect of spinal cord injury (SCI). Methods From a total of 65 patients, 17 (26%) patients suffered on admission from SCI. Twenty-five patients underwent anterior, 25 posterior, and 15 circumferential cervical surgery for a single cervical injury. Sagittal roentgenographic parameters were measured in 65 age-matched asymptomatic controls and in patients on admission, eight months postoperatively and at final follow-up (lower C2-C7 curvature, cervical sagittal vertical axis (cSVA), spinocranial angle (SCA), T1-slope, neck tilt (NT), thorax inlet angle (TIA), cervical tilt (CT), cranial tilt (CrT), and occiput–C2 angle (C0-C2)). In the last evaluation, SCI patients were compared with their counterparts without SCI using national validated HRQOL instruments (SF-36 and neck disability index (NDI)). Results Fusion included an average of 3 vertebrae (range 2-4 vertebrae). All 65 patients were followed for an average of 5.5 years, (range 3-7 years) postoperatively. In the last evaluation, 10 (15.4%) patients with incomplete SCI improved postoperatively at 1-2 grades. At the last observation, patients with SCI showed poorer HRQOL scores than their counterparts without SCI. In particular, each SF-36 domain score was correlated with SCA, T1-slope, cSVA, and CT. At baseline, patients showed higher NT, CrT, and C0-C2 angle than controls. Eight months postoperatively, cSVA, NT, TIA, and cranial tilt (CrT) were increased in patients. In the last observation, there was difference in the sagittal roentgenographic parameters between patients with SCI compared to those without SCI. Patients aged ≥55 years had postoperatively increased cSVA, NT, and CrT compared to their younger counterparts. Conclusion At the final observation, HRQOL scores were lower in patients with SCI than in their non-SCI counterparts, obviously because of the associated neurologic impairment. SF-36 scores correlated with several sagittal roentgenographic parameters. These correlations should be taken in consideration by spine surgeons when performing cervical spine surgery for fresh cervical spine injuries.

Accuracy and reliability of the AO Spine subaxial cervical spine classification system grading subaxial cervical facet injury morphology.

A classification system was recently developed by the international association AO Spine for assessing subaxial cervical spine fractures. Significant variability exists between users of the facet component, which consists of four morphological types (F1-F4). The primary aims of this study were to assess the diagnostic accuracy and reliability of this new system's facet injury morphological classifications. A survey consisting of 16 computed tomography (CT) scans of patients with cervical facet fractures was distributed to spine surgeon members of AO Spine Latin America. To provide a gold standard diagnosis for comparison, all 16 injuries had been classified previously by six co-authors and only were included after total consensus was achieved. Demographic and surgical practice characteristics of all respondents were analyzed, and diagnostic accuracy calculated. Inter- and intra-observer agreement rates were calculated across two survey rounds, conducted one month apart. A total of 135 surgeons completed both surveys, among whom the mean age was 41.6years (range 26-71), 130 (96.3%) were men, and 83 (61.5%) were orthopedic surgeons. The mean time in practice as a spine surgeon was 9.7years (1-30). The overall diagnostic accuracy of all responses was 65.4%. Inter-observer and intra-observer agreement rates for F1/F2/F3/F4 were 55.4%/47.6%/64.0%/94.7% and 60.0%/49.1%/58.0%/93.0%, respectively. This study evaluates the AO Spine Classification System specifically for facet injuries involving the subaxial cervical spine in a large sample of spine surgeons. There was significant variability in diagnostic accuracy for F1 through F3-type fractures, whereas almost universal agreement was achieved for F4-type injuries.

CT Scan in Subaxial Cervical Facet Injury: Is It Enough for Decision-Making?

Cross-sectional survey. Assessment of subaxial cervical facet injuries using the AO Spine Subaxial Cervical Spine Injury Classification System is based on CT scan findings. However, additional radiological evaluations are not directly considered. The aim of this study is to determine situations in which spine surgeons request additional radiological exams after a facet fracture. A survey was sent to AO Spine members from Latin America. The evaluation considered demographic variables, routine use of the Classification, as well as the timepoint at which surgeons requested a cervical MRI, a vascular study, and/ or dynamic radiographs before treatment of facet fractures. There was 229 participants, mean age 42.9 ± 10.2 years; 93.4% were men. Orthopedic surgeons 57.6% with 10.7 ± 8.7 years of experience in spine surgery. A total of 86% used the Classification in daily practice. An additional study (MRI/vascular study/and dynamic radiographs) was requested in 53.3%/9.6%/43.7% in F1 facet injuries; 76.0%/20.1%/50.2% in F2; 89.1%/65.1%/28.4% in F3; and 94.8%/66.4%/16.6% in F4. An additional study was frequently required: F1 72.5%, F2 86.9%, F3 94.7%, and F4 96.1%. Spine surgeons generally requested additional radiological evaluations in facet injuries, and MRI was the most common. Dynamic radiographs had a higher prevalence for F1/F2 fractures; vascular studies were more common for F3/F4 especially among surgeons with fewer years of experience. Private hospitals had a lower spine trauma cases/year and requested more MRI and more dynamic radiographs in F1/F2. Neurosurgeons had more vascular studies and dynamic radiographs than orthopedic surgeons in all facet fractures.

Comparison of anterior-only versus combined anterior and posterior fusion for unstable subaxial cervical injuries: a meta-analysis of biomechanical and clinical studies.

The purpose of the present study was to perform a meta-analysis comparing biomechanical and clinical outcomes between anterior-only and combined anterior and posterior fusions to determine which method of cervical fusion yielded better results for unstable cervical injuries. The MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science and SCOPUS electronic databases were searched for relevant articles published through 2000-2019 that compared the biomechanical and clinical outcomes of anterior-only and combined anterior and posterior fusion for unstable cervical fracture. Eight biomechanical and four clinical studies were included in the analysis. There were significant biomechanical differences between the groups with respect to flexion-extension, axial rotation and lateral bending. Combined fusion provided better biomechanical stability for unstable cervical injuries than anterior-only fusion, regardless of the number of corpectomies or the presence of a posterior column injury. However, despite significant biomechanical differences, there were no significant differences in clinical outcomes, such as the degree of neurologic improvement and complications between the two groups. Anterior-only and combined anterior and posterior fusions for unstable subaxial cervical injuries can both restore cervical stability. Although combined fusion might have some advantages in terms of stability biomechanically, there were no significant differences in clinical outcomes, such as the degree of neurologic improvement and perioperative complications. Therefore, rather than the routine use of combined fusion for unstable cervical injuries, the selective use of anterior-only or combined fusion according to the type of injury is recommended.

The Outcome of Subaxial Cervical Injury in Adult Patients Managed Surgically Through an Anterior Approach

Objectives: We determined the Outcome of subaxial cervical injury management in adults through anterior approach open reduction and fixation injury < 72 hours.
 Material and Methods: A total of 71 patients declared to have a recent chronicle of traumatic cervical spine injury with a conventional diagnosis of subaxial injury by Magnetic Resonance Imaging (MRI) and X-Ray anteroposterior and lateral views. ASIA Impairment Scale was used for assessment and was done at the time of admission and after six months.
 Results: Mean age of the patients in our study was 38.54 ± 5.47 years. According to American Spinal Injury Association (ASIA) scale, improvement by two grades was seen in 18 cases and improvement by one – grade was observed in 48 cases. Mortality was seen in 5 cases, where 2 deaths were related to associated injury, one related to a complication of surgery and other 2 died due to aspiration complications. Out of 66 cases, the outcome was good in 49 (74.29%) and fair in 17 (25.76%).
 Conclusion: The study results revealed that Anterior Cervical Discectomy and Fusion (ACDF) is considered to be a better treatment choice for better anatomical stabilization of the spine with early reduction.
 Keywords: Subaxial cervical injury, anterior approach, ASIA (American Spinal Injury Association) scoring.

Early versus delayed decompression for traumatic cervical spinal cord injury: application of the AOSpine subaxial cervical spinal injury classification system to guide surgical timing.

Application of AOSpine subaxial cervical spine injury classification system to explore the optimal surgical decompression timing for different types of traumatic cervical spinal cord injury (CSCI). A single-center prospective cohort study was conducted that included patients with traumatic CSCIs (C3-C7) between February 2015 and October 2016. After enrollment, patients underwent either early (< 72h after injury) or late (≥ 72h after injury) decompressive surgery of the cervical spinal cord. Each group was divided into A0, A1-4, B, C/F4 and F1-3 subgroups. The primary outcomes were ordinal changes in the ASIA Impairment Scale (AIS) and the Spinal Cord Independence Measure III (SCIM version 3) at a 12-month follow-up. The secondary outcomes included length of hospital stay, postoperative neurological deterioration, other complications and mortality. A total of 402 patients were included. Of these, 187 patients underwent early decompression surgery, and 215 patients underwent delayed decompression surgery. Statistical results included the following comparisons of the early vs late groups: AIS improvement ≥ 1 grade (combined groups: P < 0.0001; A0: P = 0.554; A1-4: P = 0.084; B: P = 0.013; C/F4: P = 0.040; F1-3: P = 0.742); AIS improvement ≥ 2 grades, P = 0.003 for all groups; SCIM version 3 (combined groups: P < 0.0001; A0: P = 0.126; A1-4: P = 0.912; B: P = 0.006; C/F4: P = 0.111; F1-3: P = 0.875). Type A and F1-3 fractures are not required to undergo aggressive early decompression. Type B and type C/F4 fractures should receive early surgical treatment for better clinical outcomes. These slides can be retrieved under Electronic Supplementary Material.

Risk Factors for Poor Prognosis of Cervical Spinal Cord Injury with Subaxial Cervical Spine Fracture-Dislocation After Surgical Treatment: A CONSORT Study.

BackgroundThe objective of the study was to identify risk factors for poor prognosis of cervical spinal cord injury (SCI) with subaxial cervical fracture-dislocation after surgical treatment.Material/MethodsA total of 60 cervical SCI patients with subaxial cervical fracture-dislocation were primarily included in the study from April 2013 to April 2018. All the enrolled subjects received surgical treatment. The enrolled patients with complete follow-up record were divided into 2 groups based on the neural function prognosis: a non-functional restoration group and a functional restoration group. Multivariate regression analysis was performed to identify independent risk factors for poor prognosis of SCI after surgical treatment.ResultsFifty-five subjects were included in this study, and the follow-up time ranged from 8.5 to 44.5 months. A total of 25 subjects were categorized into the non-functional restoration group and 30 subjects into the functional restoration group. According to the results of multivariate regression analysis, time from injury to operation (more than 3.8 days), subaxial cervical injury classification (SLIC, score more than 7.5), and maximum spinal cord compression (MSCC, more than 55.8%) are independent risk factors for poor prognosis of SCI after surgical treatment (p<0.05), with AUCs of 0.95 (time from injury to operation), 0.91 (SLIC score), and 0.96 (MSCC).ConclusionsTime from injury to operation (more than 3.8 days), SLIC score (more than 7.5), and MSCC (more than 55.8%) are independent risk factors for poor prognosis of SCI with subaxial cervical fracture-dislocation after surgical treatment.

Surgical Practice in Traumatic Spinal Fracture Treatment with Regard to the Subaxial Cervical Injury Classification and Severity and the Thoracolumbar Injury Classification and Severity Systems: A Review of 58 Patients at the University of Wisconsin

Spine surgeons at a Level 1 Trauma Center have observed a high incidence of spine and spinal cord injuries owing to falls from tree stands. These injuries have been retrospectively reviewed in the context of the Thoracolumbar Injury Classification and Severity (TLICS) and the Subaxial Cervical Injury Classification and Severity (SLICS) classification systems to assess inter-user reliability and validity. We hypothesize that the inter-rater reliability will be similar between neuroradiology and neurosurgery raters and validity of the scoring system will be maintained at our institution. The University of Wisconsin Hospital and Clinics' trauma database was reviewed for tree stand-related injuries from 1999 to 2013, with a focus on patients suffering from spine and spinal cord injuries. The TLICS and SLICS scores were then independently determined for these injuries by a neurosurgeon and a neuroradiologist. When cases were grouped by management recommendation (operative, equivocal, and nonoperative) reviewer agreement was 12/15 (80%) of SLICS and 38/52 (73%) of TLICS scores. Operative SLICS positive predictive value reached 100%, however, with a wide confidence interval. Conversely, the SLICS negative predictive value was poor at 54%-60%, with frequent operative treatment for patients assigned nonoperative scores. TLICS scores reached 77.8% and 93.3% positive predictive value per reviewer, whereas negative predictive values reached 93.9% and 89.2%, respectively. The TLICS and SLICS systems provide good-to-excellent inter-rater reliability. SLICS validity was poor, whereas TLICS was reasonable for nonoperative cases and moderate for operative cases. Systems such as the TLICS and the SLICS may be best applied in the educational setting to confirm the fracture morphology and presence or absence of ligamentous injury between surgeons and radiologists.

Treatment of Injuries to the Subaxial Cervical Spine: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU).

Study Design:Expert consensus.Objectives:To establish treatment recommendations for subaxial cervical spine injuries based on current literature and the knowledge of the Spine Section of the German Society for Orthopaedics and Trauma.Methods:This recommendation summarizes the knowledge of the Spine Section of the German Society for Orthopaedics and Trauma.Results:Therapeutic goals are a stable, painless cervical spine and protection against secondary neurologic damage while retaining maximum possible motion and spinal profile. The AOSpine classification for subaxial cervical injuries is recommended. The Canadian C-Spine Rule is recommended to decide on the need for imaging. Computed tomography is the favoured modality. Conventional x-ray is preserved for cases lacking a “dangerous mechanism of injury.” Magnetic resonance imaging is recommended in case of unexplained neurologic deficit, prior to closed reduction and to exclude disco-ligamentous injuries. Computed tomography angiography is recommended in high-grade facet joint injuries or in the presence of vertebra-basilar symptoms. A0-, A1- and A2-injuries are treated conservatively, but have to be monitored for progressive kyphosis. A3 injuries are operated in the majority of cases. A4- and B- and C-type injuries are treated surgically. Most injuries can be treated with anterior plate stabilization and interbody support; A4 fractures need vertebral body replacement. In certain cases, additive or pure posterior instrumentation is needed. Usually, lateral mass screws suffice. A navigation system is advised for pedicle screws from C3 to C6.Conclusions:These recommendations provide a framework for the treatment of subaxial cervical spine Injuries. They give advice about diagnostic measures and the therapeutic strategy.

Neurologic Status on Presentation as Predictive Measurement in Success of Closed Reduction in Traumatic Cervical Facet Fractures.

Dislocations to cervical facets resulting from traumatic injury often lead to neurologic impairment and can be treated both surgically and in a closed manner. We sought to evaluate the utilization of closed reduction in the initial management of bilateral facet dislocations over the past 10 years at our institution. We retrospectively reviewed the charts of patients who experienced subaxial cervical facet injury within the Penn Health System between 1 June 2006 and 1 June 2016 to identify patients with bilateral jumped/perched facets. The neurologic injury was identified on the basis of the American Spinal Injury Association (ASIA) spinal cord injury score. Analysis of variance and 2-sample t-tests were used to compare continuous distributions, and chi-square tests were used to compare categorical distributions. We focused our analyses on patients who presented with bilateral jumped/perched facets with (ASIA A and B) or without (ASIA C, D, E) complete voluntary motor deficit and underwent attempted closed reduction. We found that the rate of successful closed reduction was significantly higher in incomplete motor deficits (5/5, P=0.04, chi-square test) as compared with complete motor deficits (n= 2/11). Our results demonstrate a significant difference in the success rate of closed reduction in patients with good neurologic status on presentation (ASIA A or B), compared with those with poor neurologic status (ASIA C, D, and E). These results suggest that closed reduction should be attempted in patients with good motor examinations on presentation, whereas those with significant deficits may benefit from earlier surgical intervention.

Biomechanical study of the stability of subaxial cervical anterior transpedicular screw fixation for three-column injury

To compare the stability of subaxial cervical anterior transpedicular screw(ATPS) fixation and three traditional fixations for three-column injury. Six specimens of cervical spine were prepared. After measurememt of the range of motion(ROM) in intact state, the specimens were made into three-column injury models. The models were reconstructed with an anterior cervical cage, and stabilized by ATPS, anterior plate(AP), anterior plate + lateral mass screw(AP+LMS) and posterior transpedicular screw(PTPS). The ROM of the models in the four states were measured, and the results of data were compared after standardization. The normalized ROM of ATPS state in flexion-extension, lateral bending, axial rotation were(77.17±4.75)%, (82.00±2.61)%, (83.17±2.23)%, which were significant small than those in intact state(P<0.05). The normalized ROM of AP state in flexion-extension, lateral bending, axial rotation were(119.67±7.42)%, (116.33±7.53)%, (112.67±5.99)% , which were significant larger than those in intact state(P<0.05). The normalized ROM of AP in all directions were significant larger than those of ATPS(P<0.05). There was no significant difference between normalized ROM of PTPS state and those of ATPS state in flexion-extension and lateral bending(P>0.05). The normalized ROM of PTPS state in axial rotation was(6.83±2.48)% and was significant larger than that of ATPS state(P=0.009). The normalized ROM of AP+LMS state in flexion-extension was(68.50±2.43)%, which was significant smaller than that of ATPS state(P=0.003). There was no significant difference between the normalized ROM of AP+LMS state and those of ATPS state in lateral bending and axial rotation(P>0.05). Subaxial cervical three-column injury model reconstruction by ATPS can provide the adequate primary stability, of which biomechanics property is superior compared to AP and PTPS, and is similar to that of AP+LMS. It can be applied to the patients with no need to decompression and reduction through posterior approach.

Traumatic subaxial cervical facet subluxation and dislocation: epidemiology, radiographic analyses, and risk factors for spinal cord injury

Background ContextDistractive flexion injuries (DFIs) of the subaxial cervical spine are major contributors to spinal cord injury (SCI). Prompt assessment and early intervention of DFIs associated with SCI are crucial to optimize patient outcome; however, neurologic examination of patients with subaxial cervical injury is often difficult, as patients commonly present with reduced levels of consciousness. Therefore, it is important to establish potential associations between injury epidemiology and radiographic features, and neurologic involvement. PurposeThe aims of this study were to describe the epidemiology and radiographic features of DFIs presenting to a major Australian tertiary hospital and to identify those factors predictive of SCI. The agreement and repeatability of radiographic measures of DFI severity were also investigated. Study Design/SettingThis is a combined retrospective case-control and reliability-agreement study. Patient SampleTwo hundred twenty-six patients (median age 40 years [interquartile range = 34]; 72.1% male) who presented with a DFI of the subaxial cervical spine between 2003 and 2013 were reviewed. Outcome MeasuresThe epidemiology and radiographic features of DFI, and risk factors for SCI were identified. Inter- and intraobserver agreement of radiographic measurements was evaluated. MethodsMedical records, radiographs, and computed tomography and magnetic resonance imaging scans were examined, and the presence of SCI was evaluated. Radiographic images were analyzed by two consultant spinal surgeons, and the degree of vertebral translation, facet apposition, spinal canal occlusion, and spinal cord compression were documented. Multivariable logistic regression models identified epidemiology and radiographic features predictive of SCI. Intraclass correlation coefficients (ICCs) examined inter- and intraobserver agreement of radiographic measurements. ResultsThe majority of patients (56.2%) sustained a unilateral (51.2%) or a bilateral facet (48.8%) dislocation. The C6–C7 vertebral level was most commonly involved (38.5%). Younger adults were over-represented among motor-vehicle accidents, whereas falls contributed to a majority of DFIs sustained by older adults. Greater vertebral translation, together with lower facet apposition, distinguished facet dislocation from subluxation. Dislocation, bilateral facet injury, reduced Glasgow Coma Scale, spinal canal occlusion, and spinal cord compression were predictive of neurologic deficit. Radiographic measurements demonstrated at least a “moderate” agreement (ICC>0.4), with most demonstrating an “almost perfect” reproducibility. ConclusionsThis large-scale cohort investigation of DFIs in the cervical spine describes radiographic features that distinguish facet dislocation from subluxation, and associates highly reproducible anatomical and clinical indices to the occurrence of concomitant SCI.

Polyetheretherketone Cage with Demineralized Bone Matrix Can Replace Iliac Crest Autografts for Anterior Cervical Discectomy and Fusion in Subaxial Cervical Spine Injuries.

ObjectiveThis study aimed to compare the clinical and radiologic outcomes of patients with subaxial cervical injury who underwent anterior cervical discectomy and fusion (ACDF) with autologous iliac bone graft or polyetheretherketone (PEEK) cages using demineralized bone matrix (DBM).MethodsFrom January 2005 to December 2010, 70 patients who underwent one-level ACDF with plate fixation for post-traumatic subaxial cervical spinal injury in a single institution were retrospectively investigated. Autologous iliac crest grafts were used in 33 patients (Group I), whereas 37 patients underwent ACDF using a PEEK cage filled with DBM (Group II). Plain radiographs were used to assess bone fusion, interbody height (IBH), segmental angle (SA), overall cervical sagittal alignment (CSA, C2–7 angle), and development of adjacent segmental degeneration (ASD). Clinical outcome was assessed using a visual analog scale (VAS) for pain and Frankel grade.ResultsThe mean follow-up duration for patients in Group I and Group II was 28.9 and 25.4 months, respectively. All patients from both groups achieved solid fusion during the follow-up period. The IBH and SA of the fused segment and CSA in Group II were better maintained during the follow-up period. Nine patients in Group I and two patients in Group II developed radiologic ASD. There were no statistically significant differences in the VAS score and Frankel grade between the groups.ConclusionThis study showed that PEEK cage filled with DBM, and plate fixation is at least as safe and effective as ACDF using autograft, with good maintenance of cervical alignment. With advantages such as no donor site morbidity and no graft-related complications, PEEK cage filled with DBM, and plate fixation provide a promising surgical option for treating traumatic subaxial cervical spine injuries.

AOSpine Subaxial Cervical Spine Injury Classification System

Introduction The purpose of this project is to describe a morphology-based subaxial cervical traumatic injury classification system. Similar to the effort put toward the thoracolumbar system, the goal was to develop a comprehensive yet simple classification system with high intra and interobserver reliability to be used for clinical and research purposes. Material and Methods A subaxial cervical spine injury classification system was developed using a consensus process. All investigators were required to successfully grade 10 cases to demonstrate comprehension of the system before grading 30 additional cases on two occasions, 1 month apart. Kappa coefficients ( κ) were calculated for interobserver and intraobserver reliability. Results The classification system is based on the following three injury types: compression injuries (A), tension band injuries (B), and translational injuries (C), with additional descriptions for facet injuries, as well as patient-specific modifiers and neurologic status. Interobserver and intraobserver reliability was substantial for all injury subtypes ( κ = 0.64 and 0.75, respectively). Conclusion The AOSpine subaxial cervical spine injury classification system demonstrated substantial reliability in this initial assessment, and could be a valuable tool for patient care and for research purposes.

The Use of a Stand-Alone Interbody Fusion Cage in Subaxial Cervical Spine Trauma: A Preliminary Report

Anterior spinal surgery has a predominant role in the treatment of traumatic lesions of the subaxial cervical spine. Plating is considered indispensable to achieve stability but may cause dysphagia, dysphonia, and adjacent-level ossification. Zero-P (Synthes GmbH, Oberdorf, Switzerland), an anchored interdisc spacer, can be used without an associated plate. The present study aimed to test if this new implant would be associated with a low rate of dysphagia and other short-term complications compared with the standard for anterior spinal fusion surgery and would be able to achieve a solid fusion and maintain correct metamere alignment. This is a preliminary presentation of a clinical case series of patients with subaxial cervical injuries who underwent anterior interbody fusion. From July 2009 until September 2011, 12 patients were treated with a Zero-P cage. The data for analysis included operating time compared with the standard for spinal fusion surgery with a cage plus plate construct, intraoperative blood loss, clinical and radiographic results, and complications. In the postoperative period no patient had neurologic worsening. One patient experienced transient dysphonia and moderate dysphagia. All the patients were followed up for a minimum of 6 months (mean: 13 months; range: 6-27 months). Stability and fusion were obtained in all patients together with correct metamere alignment. We presented the preliminary results of a clinical case series. Our results support the initiation of prospective randomized trials with more patients and longer follow-up.