Cervical Stabilization Research Articles

C1 anatomy and dimensions relative to pedicle screw placement

The recent C1 pedicle screw technique for upper cervical vertebral stabilization allows longer screws to be implanted by setting the screw entry point through the posterior arch of C1, which could provide better biomechanics. However, there is controversy regarding the placement of C1 pedicle screws at different angles. We retrospectively reviewed the computed tomography (CT) scans of 300 patients. The trajectories of medial inclination of 0°, 5°, 10°, and 15° and trajectory of the maximum medial inclination angle were designed for each C1 pedicle on CT images. Screw track length at each angle, the angle of maximum medial inclination, pedicle height, distance from the screw entry point to the midpoint of the C1 posterior tubercle, and screw perforation rate at each angle were measured. The average maximum inclination angle was 17.01°, the maximum inclination angle screw track length was 31.05 mm, and the distance from the screw entry point to the midpoint of the C1 posterior nodule was 21.65 mm. The screw perforation rate was 46.73% at 15° of medial inclination, but only 5.61% at 10°, and no screw perforation at 5°. 26.47% C1 pedicle height < 4 mm. There was no significant difference between the measured data on the left and right sides(P > 0.05), and the measurement of female patients was usually smaller and significantly different from that of male patients(p < 0.05). Our data indicate that a reasonable screw inclination angle of 10° and the safety zone of screw angle can provide safety and avoid screw perforation. However, personalized measurement before surgery is essential.

Quantitatively biomechanical response analysis of posterior musculature reconstruction in cervical single-door laminoplasty

Background and objectiveThe current trend of laminoplasty is developing toward the goal of muscle preservation and minimum tissue damage. Given this, muscle-preserving techniques in cervical single-door laminoplasty have been modified with protecting the spinous processes at the sites of C2 and/or C7 muscle attachment and reconstruct the posterior musculature in recent years. To date, no study has reported the effect of preserving the posterior musculature during the reconstruction. The purpose of this study is to quantitatively evaluate the biomechanical effect of multiple modified single-door laminoplasty procedures for restoring stability and reducing response level on the cervical spine. MethodsDifferent cervical laminoplasty models were established for evaluating kinematics and response simulations based on a detailed finite element (FE) head-neck active model (HNAM), including ① C3 – C7 laminoplasty (LP_C37), ② C3 – C6 laminoplasty with C7 spinous process preservation (LP_C36), ③ C3 laminectomy hybrid decompression with C4 – C6 laminoplasty (LT_C3 + LP_C46) and ④ C3 – C7 laminoplasty with unilateral musculature preservation (LP_C37 + UMP). The laminoplasty model was validated by the global range of motion (ROM) and percentage changes relative to the intact state. The C2 – T1 ROM, axial muscle tensile force, and stress/strain levels of functional spinal units were compared among the different laminoplasty groups. The obtained effects were further analysed by comparison with a review of clinical data on cervical laminoplasty scenarios. ResultsAnalysis of the locations of concentration of muscle load showed that the C2 muscle attachment sustained more tensile loading than the C7 muscle attachment, primarily in flexion-extension (FE) and in lateral bending (LB) and axial rotation (AR), respectively. Simulated results further quantified that LP_C36 primarily produced 10% decreases in LB and AR modes relative to LP_C37. Compared with LP_C36, LT_C3 + LP_C46 resulted in approximately 30% decreases in FE motion; LP C37 + UMP also showed a similar trend. Additionally, when compared to LP_C37, LT_C3 + LP_C46 and LP C37 + UMP reduced the peak stress level at the intervertebral disc by at most 2-fold as well as the peak strain level of the facet joint capsule by 2–3-fold. All these findings were well correlated with the result of clinical studies comparing modified laminoplasty and classic laminoplasty. ConclusionsModified muscle-preserving laminoplasty is superior to classic laminoplasty due to the biomechanical effect of the posterior musculature reconstruction, with a retained postoperative ROM and loading response levels of the functional spinal units. More motion-sparing is beneficial for increasing cervical stability, which probably accelerates the recovery of postoperative neck movement and reduces the risk of the complication for eventual kyphosis and axial pain. Surgeons are encouraged to make every effort to preserve the attachment of the C2 whenever feasible in laminoplasty.

Postoperative changes in nonspecific low back pain after atlantoaxial stabilization surgery

Objectives: Posterior atlantoaxial stabilization can be technically challenging. Postoperative C2 nerve dysfunction occurs as a complication of this procedure or when a lateral mass is exposed and sacrificed for screw placement. Patients with cervical pathology sometimes complain of low back pain simultaneously. In this study, we aimed to investigate the results of C1-C2 posterior stabilization and C2 nerve root sacrifice on postoperative lumbar complaints. Methods: Twenty-six patients who underwent multicentric posterior C1-C2 stabilization due to atlantoaxial dislocation were retrospectively included in the study. Those that were not sacrificed the C2 nerve root during stabilization were considered group 1 (n = 12), and those that were sacrificed the C2 nerve root were considered group 2 (n = 14). A visual Analogue Scale (VAS) was used for the neck, arm, low back, and leg pain. The EQ-5D Index was used as the overall quality of life scale. Results: Six months postoperatively, both groups showed significant (p &amp;lt; 0.01) improvement in VAS neck, arm, and low back scores between preoperative and postoperative. In addition, there was no significant improvement in the VAS leg and EQ-5D score in either of the groups. While no significant decrease was found in occipital neuralgia in group 1, it showed significant (p &amp;lt; 0.01) improvement in occipital neuralgia in group 2. Conclusions: Although the exact pathophysiology is unknown, cervical stabilization surgery and sacrification of the C2 nerve root in this surgery can, directly and indirectly, improve low back pain.

Morphometric Study and Anatomical Variation with its Incidence of Foramina Transversaria on the Lower Cervical Vertebrae

Anatomical variation of the foramina transversaria (FT) is associated with vertebral neurovascular symptoms and can cause complications after lower spine surgery, especially cervical pedicle screw (CPS) insertion. FT variation has been documented and classified in various populations, as this information can help increase cervical stability in subaxial vertebral surgery. Although the morphometry of the upper cervical spine in Thai populations has been reported, there have yet been no studies examining the features of FT. The FT of dried cervical spines (C3-C7; left and right side; n = 107, male = 53 and female = 54) were examined for morphological variation, and their anteroposterior (AP) and transverse (T) diameters were measured using a digital vernier caliper. Morphometric data and variations were compared by sex and lateral side. It was that the C3-C6 FT in both sexes were round, and the C7 FT was elliptical with an oblique right side. FT diameters did not differ significantly by sex except for the AP diameters of C6-C7 and for T diameters of C4 and C7. The left AP diameters of C3-C6 were significantly longer than the right, as were the T diameters of C4 and C7 FT. Additionally, T diameter was significantly longer than that of the AP, except that of the left C6 in male spines, which did not differ from the AP. Most FT examined were round. These findings should be considered in the provisional diagnosis of vertebral neurovascular symptoms caused by FT variation as well as that of neurovascular damage after cervical pedicle screw placement.

Posterior cervical full-endoscopic technique for the treatment of cervical spondylotic radiculopathy with foraminal bony stenosis: A retrospective study.

In the treatment of cervical spondylotic radiculopathy (CSR), spinal endoscopy has been developed vigorously in the past 30 years. However, its effectiveness and subsequent problem of cervical spine stability have always been the controversial hotspots. This study aims to conduct a retrospective study using posterior cervical full-endoscopic technique for the treatment of CSR with foraminal bony stenosis, and evaluate its clinical effect and application value. All 22 patients treated for CSR with foraminal bony stenosis using posterior cervical full-endoscopic technique were analyzed since Dec 1, 2016, to Apr 30, 2020. The data collection included operation time, length of stay, wound healing, surgical complications, visual analog scale (VAS), Japanese Orthopaedic Association (JOA) scores, intervertebral foramen diameter, intervertebral foramen area and cervical instability. The relevant indicators were observed on admission, at postoperative 1 week and 3 months, and at the last follow-up. The operation time was 141.6 ± 13.7 min. The length of stay was 6.0 ± 2.5 days. VAS and JOA at different time points after operation were decreased compared with before operation (p < 0.05). There were no statistical differences between VAS or JOA at different postoperative time points (p > 0.05). The height, anteroposterior diameter and area of intervertebral foramen after operation were significantly increased compared with before operation (p < 0.05). Posterior cervical full-endoscopic technique shows the advantages of smaller invasion, faster recovery, significant effectiveness and fewer complications in our study. Meanwhile, it has little influence on the ROM and stability of the cervical spine. Therefore, it is a minimally invasive, safe and effective surgical method for the treatment of CSR with foraminal bony stenosis.

Use of combined laryngo-bronchoscopy intubation approach in a simulated difficult airway scenario with cervical stabilization

The occurrence of unexpected difficult airway management (DAM) during endotracheal intubation (ETI) attempts represents a life-threatening scenario. The management of such challenges may improve with training in simulated DAM scenarios. Moreover, simulation allows investigation at the potential value of new devices and techniques for DAM. The combined use of laryngoscopy with fiberoptic bronchoscope (CLBI) has been proposed in this regard, but its performance by novices facing DAM remain unexplored. We performed a randomized crossover simulation study evaluating the performance of ninety-six anesthesiology residents during ETI with four approaches: direct laryngoscopy (DL), Glidescope®, McGrath® and CLBI. Increased difficulty was produced by placement of a cervical collar. Residents had maximum of 3 attempts per device/technique (up to 60 seconds per attempt). The main outcomes were success rate (SR) and corrected time-to-intubation (cTTI, with 60 seconds added for each failed attempt). Subgroup analyses were performed separating residents according to their experience (junior, n = 60; senior, n = 36).The CLBI had significantly lower SR at both 1st and 3rd attempt (31% and 64%, respectively) as compared to DL (93% and 98%), Glidescope® (70% and 86%) and McGrath® (58% and 84%), with all p &lt; 0.001. Moreover, CLBI had significantly longer cTTI (158.5 seconds; (54.3; 180)) than other devices: Glidescope® (37.6 seconds; (24.7; 88.2)), McGrath® (39.3 seconds; (20.6; 105.1)), and DL (19 seconds; (15.4; 27.2)), all p &lt; 0.002. CLBI and McGrath® were the only approaches performing better in senior as compared to junior residents. In a DAM simulated setting, anesthesiology residents had lower SR and longer cTTI with the CLBI as compared to direct and video-laryngoscopy.

The Effect of Anterior-Only, Posterior-Only, and Combined Anterior Posterior Fixation for Cervical Spine Injury with Soft Tissue Injury: A Finite Element Analysis

This finite element analysis aimed to investigate the effects of surgical procedures for cervical spine injury. A three-dimensional finite element model of the cervical spine (C2-C7) was created from computed tomography. This model contained vertebrae, intervertebral discs, anterior longitudinal ligament, and posterior ligament complex. To create the cervical spine injury model, posterior ligament complex and anterior longitudinal ligament at C3-C4 were resected and the center of the intervertebral disc was resected. We created posterior-only fixation (PF), anterior-only fixation (AF), and combined anterior-posterior fixation (APF) models. A pure moment with a compressive follower load was applied, and range of motion, annular/nucleus stress, instrument stress, and facet forces were analyzed. In all motion except for flexion, range of motion of PF, AF, and APF models decreased by 80%-95%, 85%-93%, and 97%-99% compared with the intact model. C3-C4 annulus stress of PF, AF, and APF models decreased by 28%-72%, 96%-100%, and 99%-100% compared with the intact model. Facet contact forces of PF, AF, and APF models decreased by 77%-79%, 97%-99%, and 77%-86% at C3-C4 compared with the intact model. Screw stress in the PF model was higher than in the APF model, and plate stress in the AF model was lower than in the APF model, but bone graft stress in the AF model was higher than in the APF model. Cervical stabilization was preserved by the APF model. Regarding range of motion, the PF model had an advantage compared with the AF model except for flexion. An understanding of biomechanics provides useful information for the clinician.

Extension of decompression to C2 doesn’t affect the spinal sagittal parameters compared with standard open-door laminoplasty

We modified and extended laminoplasty to the upper cervical spine on patients with canal stenosis associated with upper cervical spinal ossified lesions. However, whether the extended decompression range of laminoplasty can cause further effects on cervical stability is rarely studied at present. A retrospective study to analyze the relationship between the surgical levels and cervical sagittal parameters effects was performed in patients with cervical spondylosis myelopathy who had undergone posterior cervical expansive open-door laminoplasty with/without extending to C2. In total, 64 patients were divided into 2 groups according to the surgical levels. Radiologic outcomes of occipito-cervical angle (C0-2 Cobb angle), CL C27 Cobb angle, cervical sagittal vertical alignment, T1-Slope (T1S), T1S minus CL (T1S-CL), spino-cranial angle and center of the sella turcica-C7 SVA (St-SVA) were evaluated on lateral X-rays of the cervical spine at pre-operation, post-operation, and 2-year follow-up. The patient's health-related quality of life was obtained including neck disability index, Japanese orthopaedic association scores, and visual analog scale. Changes in sagittal parameters were observed in both groups after surgery. T1S, cervical sagittal vertical alignment, and T1S-CL significantly increased and CL decreased in 2 groups of patients postoperative. After a 2-year follow-up period, the C0-2 Cobb angle was found to increase compared to preoperative records. In addition, there were no significant differences in spino-cranial angle and st-SVA between preoperative and 2 years follow-up measurements. Health-related quality of life was improved in both groups and was not significantly different. Herein, the parameters indicated a tilting forward of the lower cervical spine and a more lordotic upper cervical spine to maintain a horizontal gaze in patients. However, C2 to 7 laminoplasty was performed to achieve satisfactory clinical results without significantly changing the spinal sagittal parameters.

Effect of ACDF combined with different degrees of partial resection of uncovertebral joints on cervical stability and degeneration: a three-dimensional finite element analysis

BackgroundTo evaluate the influence of the resection of different amounts of the uncovertebral joints on the stability of the cervical spine by comparing and analyzing the stress distribution and peak displacement characteristics of the internal fixation structures and endplates.MethodsAfter obtaining the CT data of a 34-year-old male healthy cervical spine, a three-dimensional finite element model was established and verified. The three-dimensional finite element method was used to establish the models of anterior cervical compression fusion and internal fixation surgical implants and anterior cervical compression fusion and internal fixation combined with the partial resection of different amounts of the unilateral or bilateral uncovertebral joints. The models were tested under six working conditions: flexion, extension, left bending, right bending, left rotation, and right rotation. The surgical models were compared regarding the stress distribution of the titanium mesh, titanium plate and screw, and endplate, and the peak displacement of the vertebral body.ResultsThere were no significant differences in the stress distribution and peak displacement of the vertebral body of ACDF combined with different amounts of uncovertebral joint resection in the states of flexion and extension. However, there were significant increases in the stress distribution and peak displacement of the vertebral body in the states of left and right bending and rotation. In the states of left and right bending and rotation, the stress distribution and peak displacement of the vertebral body were significantly greater in the models with bilateral partial resection of the uncovertebral joints than in the models with unilateral partial resection of the uncovertebral joints. Bilateral resection of the uncovertebral joints by 30–40% and unilateral resection of the uncovertebral joints by 40–50% resulted in the greatest increases in the maximum stress distribution of the titanium plate and screw and the peak displacement of the vertebral body.ConclusionFinite element analysis of the biomechanical changes in the cervical spine showed that anterior cervical compression fusion and internal fixation combined with bilateral resection of less than 30% of the uncovertebral joints or unilateral resection of less than 40% of the uncovertebral joints had little effect on the stability of the cervical spine.

Cervical bleeding with cervical stabilization during IUD placement: allis clamp versus single-tooth tenaculum, a randomized control trial.

To evaluate whether the use of an atraumatic Allis clamp will result in less bleeding than the standard single-tooth tenaculum for cervical stabilization during intrauterine device (IUD) placement. A single-blinded randomized controlled trial was conducted during insertions of IUDs between March 2017 and March 2018. University of Kentucky Institutional Review Board (IRB 16-1110-P3K) approval was obtained. Physicians were randomized to use either an Allis clamp or a single-tooth tenaculum for cervical stabilization. A post-procedure questionnaire was used to collect outcome measures as well as demographic and obstetric-related factors. Of the ninety-five participants, there was no difference in age, self-identified race/ethnicity, or the evaluated obstetric factors between the groups. Bleeding was present after clamp removal in 3 (6.3%) insertions using an Allis clamp and 26 (55.3%) insertions using a single-tooth tenaculum (RR = 0.113, CI = [0.037, 0.3481], p < 0.0001). There was no difference in IUD insertion success rates between the two clamps. There was no difference in the number of interventions needed to obtain hemostasis including indirect pressure, silver nitrate, monsel's solution, or stitch for hemostasis. Pain scores did not differ based on clamp type or age of patient, but were significantly different based on parity (p < 0.001) and IUD type (p < 0.003). Decreased incidence of bleeding from cervical stabilization device, with unchanged insertion success using the Allis clamp can be an alternative to the single tooth tenaculum in the procedure of IUD insertion. The trial was retrospectively registered on 1/11/22 (trial registration number NCT05187078).

Effects of Cervical Stabilization and Scapular Stabilization Exercise on the Proprioception and Craniovertebral Angle and Upper Trapezius Muscle Tone of People with Forward Head Posture

Seung-Hwan LeeㆍByoung-Ha YooㆍHyun-Seo PyoㆍDongyeop Lee, PT, PhDㆍJi-Heon Hong, PT, PhDㆍ Jae-Ho Yu, PT, PhDㆍJin-Seop Kim, PT, PhDㆍSeong-Gil Kim, PT, PhD. KSPM 2022;17:1-13. https://doi.org/10.13066/kspm.2022.17.4.1

Perioperative Complications of Open Spine Surgery in Older Adults over 90 Years of Age.

Despite perioperative risks in nonagenarian patients who undergo open spine surgery for degeneration disorder or spinal trauma being of great interest, the prevalence of complications in this group remains unclear. This study aims to examine the perioperative complications of open spine surgery in the elderly over 90 years of age. Preoperative and intraoperative characteristics including the American Society of Anesthesiologists Physical Status (ASA-PS) class, type of surgery, and complications within 30 postoperative days were retrospectively collected from the medical records of nonagenarians who underwent open spine surgery between April 2004 and July 2019 at our spine centers. A total of 48 patients met the inclusion criteria of this study. All belong to ASA-PS class 2 (69%) or 3. Preoperative American Spinal Injury Association Impairment Scale grades in trauma group were grade A in 4 cases, B in 1 case, C in 5 cases, D in 11 cases, and E in 1 case. Major complications (deep surgical site infection, cardiac event, respiratory disorder, gastrointestinal hemorrhage, and renal failure) occurred in 13 cases, and the rate of overall perioperative complications was 45.8%. One patient who underwent cervical stabilization for cervical fracture dislocation died at postoperative 13 days due to respiratory disorder. The rates of major complications and overall perioperative complications were 3.6% and 14.3% in the degenerative group and 45.5% and 81.8% in the trauma group, respectively. Especially in the trauma group, respiratory disorder occurred in 7 cases, delirium in 11 cases, and urinary tract infection in 5 cases. Although the perioperative complication rate reached 81.8% in spinal trauma cases, the complication rate in degenerative disorders was relatively low as 14.3%. Open spine surgery for degenerative disorders can be relatively safe even in nonagenarians, whereas the risks of perioperative complications, including respiratory disorder and delirium, were high in spinal trauma cases.

Refining the role of cervical spine immobilization and stabilization in pediatric non-accidental trauma, a retrospective series of 1008 patients.

Prompt detection of traumatic cervical spine injury is important as delayed or missed diagnosis can have disastrous consequences. Given the understood mechanism of non-accidental trauma (NAT), it is reasonable to suspect that cervical spine injury can occur. Current management of young children being evaluated for NAT includes placement of a rigid collar until clinical clearance or an MRI can be obtained. Currently, there exists a lack of robust data to guide cervical bracing. Anecdotally, our group has not observed a single patient with a diagnosis of NAT who required operative stabilization for cervical spine instability. This study will be the largest series to date and aims to systematically investigate this observation to determine the likelihood that children with a diagnosis of NAT harbor cervical spine instability related to their injuries. Patient data from the Children's Hospital Colorado Trauma Registry diagnosed with non-burn-only NAT were reviewed retrospectively. Children less than 4years of age pulled from the registry from January 1, 2005, to March 31, 2021, were included. Demographic, admission/discharge, imaging, and clinic management data were collected for each patient and analyzed. There were 1008 patients included in the cohort. The age at presentation ranged from 5days to 4years (mean 10.4months). No patient had X-ray or CT findings concerning for cervical instability. Three patients had MRI findings concerning for cervical instability. Two of these underwent external bracing, and the third died from unrelated injuries during their hospitalization. Only four patients were discharged in a cervical collar, and all were ultimately cleared from bracing. No patient underwent a spinal stabilization procedure. While the mechanism of injury in many NAT cases would seem to make significant cervical spine injury possible, this single-center retrospective review of a large experience indicates that such injury is exceedingly rare. Further study is merited to understand the underlying pathophysiology. However, it is reasonable to consider cervical collar clearance in the setting of normal radiographs and a reassuring neurological exam. Furthermore, if concerns exist regarding cervical spine instability on MRI, an initial trial of conservative management is warranted.

Endoscopy-assisted high anterior cervical approach in craniovertebral junction (CVJ)

Surgical procedures in the craniovertebral junction (CVJ) suffer from specific challenges due to the proximity between the cranium and spine containing the critical neurovascular structures and the brainstem, respectively. Owing to the complex transitional zone, it is highly challenging for classic surgical approaches to practically acquire the additional exposure to neurovascular structures of the CVJ. Inspired by these facts, we explore the feasibility of an endoscopy-assisted high anterior cervical approach in the CVJ. To explore the feasibility of an endoscopy-assisted approach, we quantitatively assessed the surgical corridor and extent of exposure of the CVJ in 6 cadaveric specimens using 0° and 30° endoscopes. The applied endoscopes provided adequate exposure to neurovascular structures and the brainstem in the CVJ. Notably, the resection of the anterior arch of C1 is avoided in minimal anterior clivectomy. Further, improved exposure of the CVJ is obtained after removing the odontoid. An endoscope-assisted high anterior cervical approach in the CVJ significantly preserved the cervical spine stability while minimalizing the risk of neurovascular injury within the surgical corridor.

The Impact of Suboccipital Muscle Release on Pain and Range of Motion in the Cervical Spine of Young Adults

Introduction: Limited mobility and pain in the cervical spine affect 50% of the population, leading to disability and a reduction in quality of life. It is important to use effective forms of therapy. One of them, enjoying growing popularity, is deep tissue massage, the stability of which requires confirmation in scientific research. Research objective: The aim of the study was to investigate how a single deep tissue massage therapy aimed at suboccipital muscles reduces pain and improves the range of motion in the cervical spine and how long the improvement lasts. Research materials and methods: The study participants included 41 people aged 20-34. The respondents were randomly divided into 2 groups: study (21 people) and control (20 people). The subjects completed a questionnaire consisting of 14 questions and were subjected to 2 tests for evaluating cervical spine stability: the covering membrane test and the anterior occipital membrane test. Then, the measurements of pain on the VAS scale (0-10) and the range of cervical mobility were collected. Measurements were taken before, immediately after, as well as 2 and 4 weeks following the therapeutic intervention. The therapy in the study group consisted of a single, 10-minute relaxation session of the sub-occipital muscles. In the control group, cervical spine traction, lasting 30 seconds, was performed 3 times. Results: In the study group, the pain decreased statistically significantly (p&lt;0.05), before the therapy it totalled 4.33 ± 1.49, while after the therapy, its value decreased to 2.05 ± 0.86 and lasted up to 2 weeks after the massage – 2.67 ± 1.49. In the control group, the pain level before the therapy was 4.25 ± 0.76, and following the therapy, it decreased to 3 ± 0.95 and then increased to the mean value of 4 ± 1 (after 2 weeks). On average, the level equalled 4.25 ± 0.76 (after 4 weeks). In the study group, the range of flexion motion was, on average, 3.24 ± 1.00 cm, extension, mean 6.90 ± 1.14 cm, lateral flexion to the left, on avg. 4.76 ± 0.62, to the right on avg. 4.90 ± 1.04 cm, left rotation on avg. 8.43 ± 0.81, and right rotation on avg., 8.19 ± 1.08 cm. After deep tissue massage therapy, the results differed from the range of motion results obtained in the control group: flexion totalled 5.67 ± 0.48 cm immediately after therapy and 4.90 ± 1.34 cm 2 weeks post-intervention, extension 8.57 ± 0.87 cm immediately after therapy and 7.62 ± 1.47 cm 2 weeks after therapy, and finally, left lateral flexion 5.52 ± 0.81 directly following the therapy and 5.43 ± 0.93 cm 2 weeks after therapy. Conclusions: 1. Single-session deep tissue massage therapy significantly reduces pain and increases range of motion in the cervical spine. 2. The effects last up to 2 weeks following the therapy.

Subaxial cervical spine ligamentous instability anterior versus posterior fixation: prospective nonrandomized study

BackgroundThe goals of cervical internal fixation are to provide immediate stability to control an unstable segment and to improve bony union. Early cervical fixation methods preferred a posterior approach and consisted of simple wire and cancellous bone graft. Later, anterior, and posterior fixation became recent additions to surgeon’s armamentarium.ObjectivesComparing between anterior and posterior fixation in cervical subaxial ligamentous subluxation regarding the applicability, safety, and clinical efficacy in achieving stability and enhancing bony union. Also cost-related variables are studied.MethodsThis prospective clinical and radiographic analysis was performed on 40 patients with cervical subaxial ligamentous subluxation. Half of these patients were treated with anterior cervical fixation and interlocking screws with inter-body cage fusion. The other half was treated by posterior fixation with lateral mass fixation and inter-facet bone fusion.ResultsThere were 27 male and 13 female patients with mean age 37.4 years. The level of cervical dislocation was C4–5 in four, C5–6 in 14, C6–7 in 20 and more than one level in two patients. Closed reduction was achieved in 33 patients while open reduction through the posterior approach was done in four cases and through anterior approach in other three cases. Statistically significant difference between the two groups was found for estimated blood loss and operating room time with better results in the anterior group. There were no perioperative deaths in both groups. Regarding surgery-related complications, there was injury to a cervical root during posterior fixation in two cases. There was no statistical difference between the two groups regarding the length of the hospital stay. The mean hospital stay was 7 days. Positioning of the plate and screws in all cases was satisfactory. All patients were followed up for at least 6 months. Mean follow-up period was 13 months. Vertebral body alignment (radiological stability) was achieved in all cases with anterior fixation while one case with posterior fixation showed delayed subluxation. Solid bony cage fusion was found in 85% with anterior fixation and solid bony fusion in 70% with lateral mass fixation.ConclusionsAlthough some of the literature have indicated that posterior fixation in ligamentous cervical subaxial injury is more solid than anterior fixation, yet most of these studies were done on cadaver subjects so eliminating any bony fusion, long-term stability, and hardware failure. This study proved that anterior cervical fixation is not only safer and simple procedure than posterior fixation, but also it restores the cervical stability better than the posterior fixation.

Pediatric mandibular fracture with concomitant craniovertebral ligament injuries and retroclival hematoma: A rare occurrence

The mandible is one of the most commonly fractured facial bone in children. The principle of management of pediatric mandibular fracture bears no resemblance to its adult counterpart due to concerns regarding the growing facial skeleton and development of dentition. Pediatric mandibular fractures with traumatic retroclival hematoma and concomitant craniovertebral junction injuries is an extremely rare entity reported in literature. Manipulation during operative procedure for mandibular fractures could potentially cause serious injuries to the spinal cord, leading to significant disability and mortality. The authors report a case of a 12-year-old child with right parasymphysis and left angle of mandible fracture treated by open reduction internal fixation (ORIF). Her craniovertebral ligamentous injuries and retroclival hematoma were treated conservatively with good outcome. The presence of a halo frame for cervical spine stabilization during ORIF contributed to the difficulty in operative management. • Attending surgeons should have a high level of suspicion for cervical spine injury in pediatric maxillofacial fracture cases. • Improper examination and manipulation to the head and neck region could cause serious injuries to the spinal cord leading to devastating outcomes in the young child. • Multidisciplinary team management is important in concomitant maxillofacial and cervical spine injuries for safe and optimal outcome.

Evaluation of Cervical Endurance by Craniocervical Flexion Test in Patients with Subacromial Impingement Syndrome: A Preliminary Study

Aim: The aim of the study is to evaluate deep cervical flexor endurance in patients with subacromial impingement syndrome (SIS) and compare it with norm values proven in the literature in asymptomatic individuals. &#x0D; Materials and Methods: The patients’ age, weight, height, duration of complaints and dominant side information were recorded. 35 patients (25 female, 10 male) diagnosed with SIS by physicians participated in the study. Pain intensity was evaluated by numerical rating scale at rest, during elevation and at night. Craniocervical flexion test (CFT) is used for evaluating cervical endurance. “Stabilizer Pressure Biofeedback” device is used for this test. Two types of points are obtained as a result of this test. One is the CFT activation score, which expresses the activation level of the deep cervical muscles, and the other is the CFT performance index, which expresses the endurance of the deep cervical muscles. &#x0D; Results: Both the activation score (3.9±1.9) and the performance index (31.4±14.2) of CFT were significantly different in patients with SIS when compared with those of asymptomatic individuals.&#x0D; Conclusion: Cervical endurance is reduced in patients with SIS. Treatments including cervical stabilization should be planned in these patients.

Cervical amyloidoma of transthyretin type: a case report and review of literature

BackgroundAmyloidoma is a rare clinical entity characterized by the focal aggregation of amyloid protein within the body, void of systemic involvement. To our knowledge, there have only been 26 reports of cervical amyloidoma to date. Amyloid light chain and beta-2-microglobulin are the most common types, with only three previous reports of transthyretin (ATTR) Amyloidoma.Case presentationWe report a case of a 71-year-old male who presented with worsening strength and coordination of his upper extremities, right upper-leg pain, unsteady gait, and a reduced range of motion of his neck in all planes. Magnetic resonance imaging revealed a solitary mass compressing the spinal cord at C1-C2. Treatment consisted of cervical decompression and stabilization. Pathological examination confirmed solitary amyloid deposition of ATTR. Postoperative neurological assessment revealed improved balance, gait, hand function, and grip strength. Investigational imaging was ordered 8 months postoperatively revealing no evidence of systemic involvement, confirming the diagnosis of cervical ATTR amyloidoma. A discussion is provided surrounding the published literature of ATTR amyloidoma with description of the typical presentation, management, and outcomes of this rare pathology.ConclusionPrevious cases and studies indicate clinical signs such as ligamentum of flavum hypertrophy and carpal tunnel syndrome may precede focal ATTR spinal disposition. Outcomes for amyloidoma are generally favourable, as tumour resection prevents irreversible deficits. Patients have a low rate of recurrence with an overall excellent prognosis following resection and stabilization.

Laminoplasty on Kyphotic Cervical Alignments Suggests Poor Surgical Outcomes: A Comparative Finite Element Analysis of Laminoplasty on Different Alignments

Cervical laminoplasty is a useful for treatment for cervical myelopathy. However, this procedure has limitations for kyphotic cervical alignments. We used the finite element (FE) analysis and investigated the biomechanical changes in intact and laminoplasty models with lordosis, straight, and kyphosis cervical alignments. A three-dimensional FE model of the cervical spine (C2–C7) with ligaments was created from computer tomography. The model was modified with the following cobb angles (a) intact–lordotic model (intact–L; C2–C7 angle: −10°), (b) intact–straight model (intact–S; C2–C7 angle: 0°), and (c) intact–kyphotic model (intact–K; C2–C7 angle: 10°). The C3–C6 laminoplasty was conducted on the three intact models, represented by the laminoplasty–lordosis model (LM–L), laminoplasty–straight model (LM–S), and laminoplasty–kyphosis model (LM–K), respectively. Pure moment with compressive follower load of 100 N to represent the weight of the head/cranium and cervical muscle stabilization was applied to these models and the range of motion (ROM), annular stress, nucleus stress and facet forces were analyzed. ROM of intact–K and LM–K increased when compared to the other models. The LM–K had the highest mobility with 324% increase in ROM observed under extension, compared to LM–L. In addition, the annular stresses and nucleus stresses in intact–K and LM–K were higher compared to the other models. The maximum increase in annular stresses was about 309% in LM–K compared to the LM–L, observed at the C3–C4 segment. However, the facet contact forces were lower in the intact–K and LM–K, compared to the other models. Cases with cervical kyphosis alignment are at a disadvantage compared to cases with lordosis or straight alignment and should be treated with caution.