The deflection of fatigued neck.

The human neck is a unique mechanical structure, highly flexible but fatigue prone. The rising prevalence of neck pain and chronic injuries has been attributed to increasing exposure to fatigue loading in activities such as prolonged sedentary work and overuse of electronic devices. However, a causal relationship between fatigue and musculoskeletal mechanical changes remains elusive. This work aimed to establish this relationship through a unique experiment design, inspired by a cantilever beam mechanical model of the neck, and an orchestrated deployment of advanced motion-force measurement technologies including dynamic stereo-radiographic imaging. As a group of 24 subjects performed sustained-till-exhaustion neck exertions in varied positions-neutral, extended, and flexed, their cervical spine musculoskeletal responses were measured. Data verified the occurrence of fatigue and revealed fatigue-induced neck deflection which increased cervical lordosis or kyphosis by 4-5° to 11°, depending on the neck position. This finding and its interpretations render a renewed understanding of muscle fatigue from a more unified motor control perspective as well as profound implications on neck pain and injury prevention.

Fatal cervical myelopathy in a child with glutaric aciduria type 1.

We report the case of a Syrian female refugee with late diagnosis of glutaric aciduria type 1 characterised by massive axial hypotonia and quadriplegia who only started adequate diet upon arrival in Switzerland at the age of 4 years, after a strenuous migration journey. Soon after arrival, she died from an unexpected severe upper cervical myelopathy, heralded by acute respiratory distress after a viral infection. This was likely due to repeated strains on her hypotonic neck and precipitated by an orthotopic os odontoideum who led to atlanto-axial subluxation. This case reminds us not to omit handling patients with insufficient postural control and hypotonia with great care to avoid progressive cervical myelopathy.

Shifting Perspectives: Equal Blunt Cerebrovascular Risk in Low-Versus High-Energy Cervical Fracture.

INTRODUCTION: Clinical implications of screening for blunt cerebrovascular injury (BCVI) after low-energy mechanisms of injury (LEMI) remain unclear. We assessed BCVI incidence and outcomes in LEMI versus high-energy mechanisms of injury (HEMI) patients. METHODS: In this retrospective cohort study, blunt trauma adults admitted between July 2015 and June 2021 with cervical spine fractures, excluding single spinous process, osteophyte, and chronic fractures were included. Demographics, comorbidities, injuries, screening and treatment data, iatrogenic complications, and mortality were collected. Our primary end point was to compare BCVI rates between LEMI and HEMI patients. RESULTS: Eight hundred sixty patients (78%) were screened for BCVI; 120 were positive for BCVI. LEMI and HEMI groups presented similar BCVI rates (12.6% versus 14.4%; P = 0.640). Compared to HEMI patients (n = 95), LEMI patients (n = 25) were significantly older (79 ± 14.9 versus 54.3 ± 17.4, P < 0.001), more likely to be on anticoagulants before admission (64% versus 23.2%, P < 0.001), and less severely injured (LEMI injury severity score 10.9 ± 6.6 versus HEMI injury severity score 18.7 ± 11.4, P = 0.001). All but one LEMI and 90.5% of the HEMI patients had vertebral artery injuries with no significant difference in BCVI grades. One HEMI patient developed acute kidney injury because of BCVI screening. Eleven HEMI patients developed BCVI-related stroke with two related mortalities. One LEMI patient died of a BCVI-related stroke. CONCLUSIONS: BCVI rates were similar between HEMI and LEMI groups when screening based on cervical spine fractures. The LEMI group exhibited no screening or treatment complications, suggesting that benefits may outweigh the risks of screening and potential bleeding complications from treatment.

Cutibacterium namnetense osteosynthetic cervical spine infections: experience with two cases.

We report two uncommon cases of osteosynthetic cervical spine infection. Clinical patient features, microbiological strain characteristics, diagnostic methods, and treatment were analyzed. Both patients were male, and one had risk factors for surgical site infection. During surgery, perioperative samples were positive yielding an anaerobic microorganism identified as Cutibacterium namnetense by MALDI-TOF MS and confirmed by 16S rRNA/gyrB genes sequencing. All isolates were fully susceptible. C. namnetense osteosynthetic cervical spine infections are rare. Both cases were early surgical site infections. Bruker MALDI-TOF MS appears to be an excellent tool for rapid and accurate identification. Amoxicillin seems to be an option for the treatment.

Feasibility and Safety of Lateral and Posterolateral Percutaneous Vertebroplasty of Osteolytic C1-C2 Lesions under Computed Tomography Guidance and Local Anesthesia.

OBJECTIVE: To evaluate the safety and effectiveness of the lateral or posterolateral percutaneous vertebroplasty (PVP) of osteolytic C1-C2 lesions performed under computed tomography (CT) guidance and local anesthesia. MATERIALS AND METHODS: Retrospective study of 16 consecutive patients (11 females and 5 males, aged from 24 to 86 years, median 65.5 years) who underwent 17 lateral or posterolateral PVP. Pain status was assessed using a visual analog scale (VAS). Patients were evaluated preoperatively as baseline and at 24 hours, 1, 6, 12 months postoperatively, or until the patient died or was lost to follow-up. The Oswestry Disability Index (ODI) was used to evaluate the patients' functional disability preoperatively. The adverse events were recorded using the SIR classification. RESULTS: The technical success was 100% (17/17) for a median SINS score about 13.5 (IQR [6.75, 20.25]). Mean clinical follow up was 10.1 months (range, 6-36 months; median 19.5 months, IQR [4, 35]). Mean VAS score decreased significantly from 7.5 ± 2.1 preoperatively to 1.6 ± 1.5 24 hours postoperatively, and 1.0 ± 1.1, 1.5 ± 1, and 0.5 ± 1.5 at 1, 6, 12 months respectively (all p<.001). No severe adverse events were observed but 3 cases of asymptomatic cement leakage (SIR grade 1) (17.6% (3/17)). CONCLUSIONS: Lateral and posterolateral PVP performed under CT guidance and local anesthesia is safe and effective to treat symptomatic osteolytic C1-C2 lesions.

The Effect of Concomitant Spinal Cord Injury on Postoperative Health-related Quality of Life After Traumatic Subaxial Cervical Spine Injuries: A Nationwide Registry Study.

OBJECTIVE: To evaluate the effect of spinal cord injury (SCI) on the health-related quality of life (HRQoL) in patients surgically treated for traumatic subaxial cervical spine injuries and investigate the agreement between objective neurologic outcomes and patient reported outcome measures (PROMs) in that context. STUDY DESIGN: Observational study on prospectively collected multi-institutional registry data. SETTING: Sweden. PARTICIPANTS: Patients with traumatic subaxial spine injuries identified in the Swedish Spine Registry (Swespine) between 2006 and 2016. INTERVENTIONS: Anterior, posterior, or anteroposterior cervical fixation surgery. MAIN OUTCOMES: Patient-reported outcome measures (PROMs) consisting of EQ-5D-3Lindex and Neck Disability Index (NDI). RESULTS: Among the 418 identified patients, 93 (22%) had a concomitant SCI. In this group, 30 (32%) had a complete SCI (Frankel A), and the remainder had incomplete SCIs (17%) Frankel B; 25 (27%) Frankel C; 22 (24%) Frankel D. PROMs significantly correlated with the Frankel grade (P<.001). However, post hoc analysis revealed that the differences between adjacent Frankel grades failed to reach both statistical and clinical significance. On univariable linear regression, the Frankel grade was a significant predictor of a specific index derived from the EQ-5D-3L questionnaire (EQ-5D-3Lindex) at 1, 2, and 5 years postoperatively as well as the NDI at 1 and 2 years postoperatively (P<.001). Changes of PROMs over time from 1, to 2, and 5 years postoperatively did not reach statistical significance, regardless of the presence and degree of SCI (P>.05). CONCLUSION: Overall, the Frankel grade significantly correlated with the EQ-5D-3Lindex and NDI and was a significant predictor of PROMs at 1, 2, and 5 years. PROMs were stable beyond 1 year postoperatively regardless of the severity of the SCI.

Cervical Spinal Cord Stimulation for Failed Neck Surgery Syndrome.

PURPOSE OF REVIEW: Cervical spine pain with or without radicular symptoms is a common condition leading to high utilization of the healthcare system with over 10 million medical visits per year. Many patients undergo surgical interventions and unfortunately are still left with neck and upper extremity pain, sometimes referred to as "Failed Neck Surgery Syndrome." When these options fail, cervical spinal cord stimulation can be a useful tool to decrease pain and suffering as well as reduce prescription medication use. RECENT FINDINGS: Spinal cord stimulation is a well-established therapy for chronic back and leg pain and is becoming more popular for neck and upper extremity pain. Recent studies have explored cervical spinal cord stimulation with successful outcomes regarding improved pain scores, functional outcomes, and reduction of prescription medication use. Continued research into cervical spinal cord stimulation is essential for maximizing its therapeutic potential for patients with chronic neck and upper extremity pain. This review highlights the importance of cervical spinal cord stimulation as an option for patients with failed neck surgery syndrome.

C3-C4 cervical disc herniation producing Brown-Séquard syndrome: A case report and review of the literature.

Brown-Séquard Syndrome (BSS) is a rare form of incomplete spinal cord injury and is characterized by ipsilateral motor deficit and contralateral sensory loss. BSS is commonly associated with traumatic etiologies, but non-traumatic causes should be considered as well. A 38-year-old woman presented with a 3-week history of weakness in her right upper extremity, and she has developed numbness and tingling in her left upper and lower extremities over the past week and a half, along with some motor difficulty. Imaging showed a large right paracentral disc protrusion at the C3-C4 level causing severe spinal canal narrowing and resulting in abnormal cord signal. The patient subsequently underwent a C3-4 cervical total disk replacement. Hemovac placed during surgery was removed on post-op day one, and she was re-evaluated by PT/OT and recommended for outpatient therapies on post-op day two. Our case, along with a review of the literature, highlights those non-traumatic causes of BSS should be considered as a cause of BSS. BSS produced by a herniated cervical disc is extremely rare and is often misdiagnosed.

Injury patterns and mortality associated with near-hanging in children.

BACKGROUND: The pathophysiology of near-hanging in children is different from that of adults due to anatomic, physiologic, and injury-related mechanisms, with evidence suggesting that blunt cerebrovascular injuries (BCVI) and cervical spine injuries (CSI) are uncommon. We sought to estimate the incidence of secondary injuries and their association with mortality in pediatric near-hanging victims. METHODS: We performed a retrospective observational study of children (≤17 years) with a diagnosis code for hanging between October 1, 2015 and February 28, 2023 who presented to one of 47 geographically diverse US children's hospitals. We evaluated the incidence of the following secondary injuries: cerebral edema, pneumothorax, pulmonary edema, BCVI, and CSI. We performed Fisher's exact test with Bonferroni correction to identify associations between intentionality, sex, age, and secondary injuries with mortality. RESULTS: We included 1929 children, of whom 33.8% underwent neuroimaging, 45.9% underwent neck imaging, and 38.7% underwent neck angiography. The most common injury was cerebral edema (24.0%), followed by pulmonary edema (3.2%) and pneumothorax (2.8%). CSI (2.1%) and BCVI (0.9%) occurred infrequently. Cerebral edema, pneumothorax, pulmonary edema, and younger age (≤12 years) were associated with mortality. CONCLUSIONS: In this multi-center study of pediatric near-hanging victims, BCVI and CSI occurred rarely and were not associated with mortality. While children in our study underwent neck imaging more frequently than head imaging, cerebral edema occurred more often than other injury types and imparted the highest mortality risk. Given the rarity of BCVI and CSI, a selective approach to neck imaging may be warranted in pediatric near-hanging events.

Differentiation of the body build and posture in the population of people with intellectual disabilities and Down Syndrome: a systematic review.

BACKGROUND: The aim of the study was to identify the variables of the internal compensatory mechanisms that differentiate the body build and posture of people with Down syndrome (DS) from the intellectual disability (ID) population. It was assumed that gaining knowledge in the abovementioned aspect will allow for a better understanding of the limitation of the kinesthetic abilities of people with ID and DS and simultaneously enable to optimize the process of planning and interventions to improve physical activity in this population with the adequate use of theirs strengths in the biomechanical and morphofunctional systems. METHODS: The methodology of this systematic review was developed according to the PRISMA guidelines. A search of PubMed, EBSCO, Scopus databases was conducted to identify all studies on DS/ID and the body build and posture from 2003 to 2023. RESULTS: 395 articles were assessed to determine eligibility, while 22 studies met the inclusion criteria and were subjected to detailed analysis and assessment of their methodological quality. The differentiation of the body build and posture in DS population can be induced by both internal and external compensatory mechanisms. It is difficult to confirm the direct effect of the intrinsic variables that impact the body build and posture in the ID population, excluding people with DS. CONCLUSIONS: Compared to other ID, the intrinsic differences in the body build and posture in DS individuals were induced by gender, age, and level of ID. The tendency for diversity between DS and other ID populations in body build and posture may be determined by the presence of the third copy of chromosome 21 in DS group. Internal compensatory processes may be induced mainly by abnormalities in the structure of the cervical vertebrae and feet. IQ should not be used as the only variable that identifies the population of people with ID.

Cervical spine motion during videolaryngoscopic intubation using a Macintosh-style blade with and without the anterior piece of a cervical collar: a randomized controlled trial.

PURPOSE: Applying a cervical collar during videolaryngoscopic intubation can increase the lifting force required to achieve adequate glottic view, potentially increasing cervical spine motion. We aimed to compared cervical spine motion during videolaryngoscopic intubation between applying only the posterior piece (posterior-only group) and applying both the anterior and posterior pieces (anterior-posterior group) in patients wearing a cervical collar. METHODS: We conducted a dingle-centre, parallel-group, randomized controlled trial in 102 patients (each group, N = 51). We used a videolaryngoscope (AceScope™, Ace Medical, Seoul, Republic of Korea) with a Macintosh-style blade (AceBlade™, Ace Medical, Seoul, Republic of Korea) for videolaryngoscopic intubation. In each group (posterior-only vs anterior-posterior), we measured cervical spine motion during intubation, defined as change in cervical spine angle (calculated as cervical spine angle at intubation minus that before intubation) at three cervical spine segments on lateral cervical spine radiographs. RESULTS: The differences in mean cervical spine motion during intubation between the posterior-only and anterior-posterior groups were 1.2° (98.3% confidence interval [CI], -0.7 to 3.0), 1.0° (98.3% CI, -0.6 to 2.6), and -0.3° (98.3% CI, -2.2 to 1.7) at the occiput-C1, C1-C2, and C2-C5 segments, respectively. Mean (standard deviation) cervical spine angles at the occiput-C1, C1-C2, and C2-C5 segments in the posterior-only vs anterior-posterior groups were 10.8° (4.2) vs 9.6° (3.3) (P = 0.13), 5.6° (3.0) vs 4.7° (3.5) (P = 0.14), and 1.2° (3.7) vs 1.5° (4.3) (P = 0.74), respectively. Intubation times were shorter in the posterior-only group (median [interquartile range], 23 [19-28] sec vs 33 [20-47] sec; P = 0.003). CONCLUSIONS: In patients wearing a cervical collar, the differences in mean cervical spine motions during intubation between applying only the posterior piece and applying both the anterior and posterior pieces were approximately 1°. Intubation times were significantly shorter without the anterior piece of a cervical collar. These findings can be referred to when removal of the anterior piece of a cervical collar is considered to address difficult videolaryngoscopic intubation conditions. STUDY REGISTRATION: CRIS.nih.go.kr ( KCT0008151 ); first submitted 17 January 2023.

RéSUMé: OBJECTIF: L'application d'un collier cervical pendant l'intubation par vidéolaryngoscopie peut augmenter la force de levage requise pour obtenir une vue glottique adéquate, augmentant potentiellement le mouvement de la colonne cervicale. Nous avons cherché à comparer le mouvement de la colonne cervicale lors d'une intubation vidéolaryngoscopique entre l'application de la partie postérieure uniquement (groupe postérieur seulement) et l'application des parties antérieure et postérieure (groupe antéro-postérieur) du collier chez les patient·es portant un collier cervical. MéTHODE: Nous avons mené une étude randomisée contrôlée monocentrique, en groupes parallèles, chez 102 personnes (chaque groupe, N = 51). Nous avons utilisé un vidéolaryngoscope (AceScope™, Ace Medical, Séoul, République de Corée) avec une lame de type Macintosh (AceBlade™, Ace Medical, Séoul, République de Corée) pour l'intubation vidéolaryngoscopique. Dans chaque groupe (postérieur seulement vs antéro-postérieur), nous avons mesuré le mouvement de la colonne cervicale pendant l'intubation, défini comme un changement de l'angle de la colonne cervicale (calculé comme l'angle de la colonne cervicale à l'intubation moins celui avant l'intubation) à trois segments de la colonne cervicale sur les radiographies latérales de la colonne cervicale. RéSULTATS: Les différences dans le mouvement moyen de la colonne cervicale pendant l'intubation entre les groupes postérieur seulement et antéro-postérieur étaient de 1,2° (intervalle de confiance [IC] 98,3 %, −0,7 à 3,0), 1,0° (IC 98,3 %, −0,6 à 2,6) et −0,3° (IC 98,3 %, −2,2 à 1,7) au niveau des segments occiput-C1, C1-C2 et C2-C5, respectivement. Les angles moyens (écart type) de la colonne cervicale au niveau des segments occiput-C1, C1-C2 et C2-C5 dans le groupe postérieur seulement vs antéro-postérieur étaient de 10,8° (4,2) vs 9,6° (3,3) (P = 0,13), 5,6° (3,0) vs 4,7° (3,5) (P = 0,14), et 1,2° (3,7) vs 1,5° (4,3) (P = 0,74), respectivement. Les temps d'intubation étaient plus courts dans le groupe postérieur seulement (médiane [écart interquartile], 23 [19-28] secondes vs 33 [20 à 47] secondes; P = 0,003). CONCLUSION: Chez les patient·es portant un collier cervical, les différences dans les mouvements moyens de la colonne cervicale pendant l'intubation entre l'application uniquement de la partie postérieure et l'application des parties antérieure et postérieure du collier étaient d'environ 1°. Les temps d'intubation étaient significativement plus courts sans la partie antérieure du collier cervical. On peut se référer à ces résultats lorsque le retrait de la partie antérieure d'un collier cervical est envisagé pour prendre en charge des conditions d'intubation vidéolaryngoscopique difficiles. ENREGISTREMENT DE L'éTUDE: CRIS.nih.go.kr ( KCT0008151 ); première soumission le 17 janvier 2023.

Regional analgesia using ultrasound-guided intermediate cervical plexus block versus cervical erector spinae block for anterior cervical spine surgery: a randomized trial.

BACKGROUND: Regional analgesia techniques are crucial for pain management after cervical spine surgeries. Anesthesiologists strive to select the most effective and least hazardous regional analgesia technique for the cervical region. Our hypothesis is that an intermediate cervical plexus (IC) block can provide adequate postoperative analgesia compared to a cervical erector spinae (ES) block in patients undergoing anterior cervical spine surgery. METHODS: In this double-blind prospective trial, 58 patients were randomly assigned into two equal groups prior to the administration of general anesthesia. Patients in the IC group (n = 29) underwent ultrasound-guided bilateral intermediate cervical plexus block with 15 ml of bupivacaine 0.25% administered to each side. The ES group (n = 29) underwent ultrasound-guided bilateral cervical erector spinae plane blocks with 15 ml of 0.25% bupivacaine administered to each side at the C6 level. The primary outcome was to record the time to the first call for rescue analgesia (nalbuphine), and the secondary outcomes were to measure the performance time, the onset of the sensory block, the intraoperative fentanyl consumption, postoperative pain intensity using VAS, the postoperative total nalbuphine consumption, and postoperative complications such as nausea, vomiting, hypotension, and bradycardia. RESULTS: The performance and onset of sensory block times were significantly shorter in the IC group compared to the ES group. The time to first call for nalbuphine was significantly shorter in the IC group (7.31 ± 1.34 h) compared to the ES group (11.10 ± 1.82 h). The mean postoperative VAS scores were comparable between the two groups at the measured time points, except at 8 h, where it was significantly higher in the IC group, and at 12 h, where it was significantly higher in the ES group. The total nalbuphine consumption was significantly higher in the IC group (33.1 ± 10.13 mg) compared to the ES group (22.76 ± 8.62 mg). CONCLUSIONS: For patients undergoing anterior cervical spine surgery, the intermediate cervical plexus block does not provide better postoperative regional analgesia compared to the cervical erector spinae block. Performance time and onset time were shorter in the IC group, whereas nalbuphine consumption was lower in the ES group. TRIAL REGISTRATION: The trial was registered at clinicaltrials.gov. (NCT05577559, and the date of registration: 13-10-2022).

Pediatric cervical spine instability: evolving concepts.

The pediatric cervical spine is structurally and biomechanically unique in comparison to adults. Guidelines to assess for cervical spine instability and standard of care treatments in the pediatric population have yet to be delineated. This is due to the rarity of the condition and the lack of multicenter data published on the topic. Our review explores the biomechanics of the pediatric cervical spine and highlights evolving concepts/research over the last several decades, with special attention to the Down syndrome and complex Chiari malformation cohorts.

The incidence of reoperation for pseudarthrosis after cervical spine surgery.

INTRODUCTION: Pseudarthrosis after cervical spine surgery represents an underreported and challenging complication. Using a large multi-center surgical database, we sought to: (1) report the incidence of cervical pseudarthrosis, (2) evaluate changes in rates of cervical pseudarthrosis, and (3) describe risk factors for suboptimal outcomes after cervical pseudarthrosis surgery. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database from 2012 to 2019 was used. The primary outcome was occurrence of a cervical fusion procedure with a prior diagnosis of pseudarthrosis. Fusion for pseudarthrosis was divided into anterior and posterior approaches. Post-operative complications were classified as major or minor. Prolonged LOS was defined as exceeding the 75th percentile for total hospital stay. RESULTS: A total of 780 patients underwent cervical fusion for pseudarthrosis, and a significant increase in rates of surgery for pseudarthrosis was seen (0.25-1.2%, p < 0.001). The majority of cervical pseudarthrosis was treated with a posterior approach (66.5%). Postoperatively, 38 (4.9%) patients suffered a complication and 247 (31.7%) had a prolonged LOS. The three strongest risk factors for complications and extended LOS were > 10% weight loss preoperatively, congestive heart failure, and pre-operative bleeding disorder. CONCLUSION: Results from a large multi-center national database revealed that surgery to treat cervical pseudarthrosis has increased from 2012 to 2019. Most pseudarthrosis was treated with a posterior approach. Reoperation to treat cervical pseudarthrosis carried risk, with 5% having complications and 32% having an extended LOS. These results lay the groundwork for a future prospective study to discern the true incidence of cervical pseudarthrosis and how to best avoid its occurrence.

Is neck pain treatable with surgery?

INTRODUCTION: Neck pain is one of the most common complaints in clinical practice and can be caused by a wide variety of conditions. While cervical spine surgery is a well-accepted option for radicular pain and myelopathy, surgery for isolated neck pain is controversial. The identification of the source of pain is challenging and subtle, and misdiagnosis can lead to inappropriate treatment. MATERIALS AND METHODS AND RESULTS: We conducted a thorough literature review to discuss and compare different causes of neck pain. We then supplemented the literature with our senior author's expert analysis of treating cervical spine pathology. CONCLUSIONS: This study provides an in-depth discussion of neck pain and its various presentations, as well as providing insight into treatment strategies and diagnostic pearls that may prevent mistreatment of cervical spine pathology.

Comparison of iCT-based navigation and fluoroscopic-guidance for atlantoaxial screw placement in 78 patients with traumatic cervical spine injuries.

BACKGROUND CONTEXT: Studies have shown biomechanical superiority of cervical pedicle screw placement over other techniques. However, accurate placement is challenging due to the inherent risk of neurovascular complications. Navigation technology based on intraoperative 3D imaging allows highly accurate screw placement, yet studies specifically investigating screw placement in patients with traumatic atlantoaxial injuries are scarce. The aim of this study was to compare atlantoaxial screw placement as treatment of traumatic instabilities using iCT-based navigation or fluoroscopic-guidance with intraoperative 3D control scans. METHODS: This was a retrospective review of patients with traumatic atlantoaxial injuries treated operatively with dorsal stabilization of C1 and C2. Patients were either assigned to the intraoperative navigation or fluoroscopic-guidance group. Screw accuracy, procedure time, and revisions were compared. RESULTS: Seventy-eight patients were included in this study with 51 patients in the navigation group and 27 patients in the fluoroscopic-guidance group. In total, 312 screws were placed in C1 and C2. Screw accuracy was high in both groups; however, pedicle perforations > 1 mm occurred significantly more often in the fluoroscopic-guidance group (P = 0.02). Procedure time was on average 23 min shorter in the navigation group (P = 0.02). CONCLUSIONS: This study contributes to the available data showing that navigated atlantoaxial screw placement proves to be feasible as well as highly accurate compared to the fluoroscopic-guidance technique without prolonging the time needed for surgery. When comparing these data with other studies, the application of different classification systems for assessment of screw accuracy should be considered.

Novel MRI signs of the atlantodental space in patients with atlantoaxial dislocation.

OBJECTIVES: The type of atlantodental space tissue in patients with atlantoaxial dislocation (AAD) can help doctors understand the possibility of reduction before surgery. However, relevant research on this topic is lacking. In this study, we aimed to summarise the atlantodental space classification of patients with AAD using magnetic resonance imaging (MRI) and explore their clinical characteristics. MATERIALS AND METHODS: Preoperative 3T cervical MR images of patients who underwent posterior reduction and fixation surgery for non-traumatic AAD between 1 September 2012 and 31 July 2023 were collected. Two radiologists read and recorded the MRI results based on the standard protocol. The kappa value was used to evaluate intra- and inter-observer agreements. The patient's age, sex, body mass index, clinical symptoms, Japanese Orthopaedic Association (JOA) score, and visual analogue scale information were obtained from medical records. RESULTS: A total of 135 patients with AAD (mean age, 51.3 ± 14.0 years, 52 men) were included in the analysis. The inter-observer agreement between the two readers was 0.818 (P < 0.0001). The intra-observer consistencies were 0.882 (P < 0.0001) and 0.896 (P < 0.0001). Patients with inflexible tissue signs exhibit more irreducible in hyperextension position, and their range of motion of ADI is smaller. These patients were older and had a higher incidence of abnormal spinal cord signals and JOA scores. CONCLUSIONS: Novel MRI signs exhibited high inter- and intra-observer consistency and were associated with patient age, abnormal spinal cord signals, reducibility, range of motion of ADI, and symptoms.

Sagittal morphometry of intervertebral spaces in subaxial cervical region of asymptomatic Chinese.

PURPOSE: This study aimed to quantify and evaluate morphology of intervertebral space between neighboring cervical units using radiographic imaging indices, to help spine surgeons when performing anterior cervical discectomy and fusion (ACDF) surgery on the Chinese population. METHODS: The background and imaging parameters of the subjects were assessed. Cervical lateral radiographs were employed to measure the intervertebral height (IH), intervertebral height index (IHI), and segmental lordosis (SL). Endplate parameters measurements were conducted on sagittal T2-weighted magnetic resonance imaging (MRI), including endplate sagittal diameter (ESD), and endplate concavity depth (ECD). All individuals were divided into three age groups: individuals aged 20-35 were in group A, individuals aged 36-50 were in group B, and individuals aged over 50 were in group C. A comparison of the variables was conducted among the three groups. Additionally, these radiographic parameters were also compared between males and females. RESULTS: A total of 102 individuals were included in this study. IH was greater at C6/7 than those at other segmental levels (p < 0.001). The largest SL values were found at C6/7, while the least were found at C3/4. The superior ESD (ESDs) and ECD (ECDs) of the intervertebral space were significantly greater than those of the inferior endplates (p < 0.05). The ESD and ECD values were the largest at C6/7, while the least at C3/4. Additionally, age and gender had an influence on several parameters. IH was significantly lower in group A compared to group B (p < 0.05) and group C (p < 0.05) from C3/4 level to C6/7 level. ECDs were lower in group A compared to group B (p < 0.05) and group C (p < 0.05) at each level. IH and ESD in males were generally significantly greater than those in females at all levels (p < 0.05). CONCLUSION: The current study found that C6/7 had the greatest IH, SL, ESD, and ECD values in asymptomatic Chinese. SL gradually increased from C3/4 to C6/7 levels. IH and ECD were significantly associated with age. Males had greater IH and ESD values than females. These findings provide baseline information for planning for selection of anterior screws and intervertebral implants.

Treatment of failed cervical total disc replacements in a series of 53 cases and description of a management strategy.

PURPOSE: To describe modes of failure of cervical TDR, their related treatment strategies, and to describe a management strategy for the treatment of failed cervical TDR. METHODS: This retrospective study was based on a consecutive series of 53 cervical TDR patients who underwent removal or revision surgery. Chart review was conducted to collect general descriptive data, reasons for TDR removal/revision, duration from index implantation to re-operation, and the subsequent procedure performed. RESULTS: Among 53 patients, 36 underwent TDR removal and fusion, 16 underwent TDR removal and replacement with another TDR, and one patient's TDR was revised by repositioning. The mean duration from index surgery to removal/revision was 40.1 months (range: 3 days-222 months). In all cases, removal/revision surgery was completed without complication. The most common reason for removal was severe osteolysis, often involving C. acnes infection, and was primarily associated with one implant type. TDR removal and fusion were performed for subsidence, device migration, treatment of symptoms arising from posterior anatomy (facet joints, etc.), approach-related complications and pain. TDR replacement was feasible for hypermobility, metal allergy, implant locked in kyphosis, and oversized implant use. In one case of TDR malpositioning, the device was successfully revised into appropriate position. CONCLUSION: After cervical TDR failure, replacing a TDR with another implant can be feasible. Reasons for revision or removal after cervical TDR surgery include biomechanical failure, implant migration, surgeon or technical error, or biological reasons. The type of failure can help the surgeon create a strategy to address these complications.

Incidence and predictive factors of double crush syndrome in patients undergoing cervical surgery: a database study.

BACKGROUND: Double crush syndrome (DCS) is characterized by multiple compression sites along a single peripheral nerve. It commonly presents with persistent distal symptoms despite surgical treatment for cervical radiculopathy. Management typically involves nerve release of the most symptomatic site. However, due to overlapping symptoms with cervical radiculopathy, patients may undergo cervical surgery prior to DCS diagnosis. Due to its rarity and frequent misdiagnosis, the authors aim to utilize a large national database to investigate the incidence and associations of DCS. METHODS: The Pearldiver database was utilized to identify patients undergoing cervical surgery for the management of cervical radiculopathy. Patients were stratified into three cohorts based on their clinical course before and after cervical surgery. The primary outcome was the prevalence of DCS, and secondary outcomes included an evaluation of predictive factors for each Group, using a significance level of P < 0.05. RESULTS: Among 195,271 patients undergoing cervical surgery for cervical radiculomyelopathy, 97.95% were appropriately managed, 1.42% had potentially mids-diagnosed DCS, and 0.63% were treatment-resistant. Diabetes and obesity were significant predictors of potentially misdiagnosed DCS (P < 0.05). CONCLUSION: This study presents data indicating that 1.42% of patients who receive cervical surgery may have underlying DCS and potentially benefit from nerve release prior to undergoing surgery. A concurrent diagnosis of diabetes and obesity may predict an underlying DCS.