OBJECTIVE: To investigate the possible mechanism and fracture stability of subtypes of type B Hangman's fracture by using imaging observation. METHODS: Patients with type B Hangman's fractures admitted to multiple centers between January 2008 and October 2023 were selected as the research objects. The clinical data and imaging data of patients who met the selection criteria were extracted. The patients' age, gender, cause of fracture, disease duration, visual analogue scale (VAS) score of neck pain, neck disability index (NDI), and American Spinal Injury Association (ASIA) classification of spinal cord function were collected. Based on the imaging data, the anatomical structure of the contralateral superior articular process fracture, the relationship between the superior articular process fracture line and the position of the odontoid process, the associated posterior vertebral wall fracture and its classification, the incidence of vertebral arch floating and C _{2, 3} instability were observed. The superior articular fracture angle (SAFA), superior articular fracture displacement distance (SAFD), and C ₂ vertebral body rotation (VBRA) were measured. According to the anatomical structure of the contralateral superior articular process fracture, the patients were divided into a pedicle fracture group (POA group), a inferior articular process fracture group (IAP group), and a laminar fracture group (CSL group). The baseline data and imaging indexes were analyzed between groups, and the imaging anatomical characteristics of each subtype of fracture were observed to explore its possible mechanism and fracture stability. RESULTS: A total of 86 cases of type B Hangman's fractures were collected. There were 67 males and 19 females. The mean age was 51.0 years (range, 21-78 years). There were 48 cases of pedicle fracture (POA group), 25 cases of inferior articular process fracture (IAP group), and 13 cases of laminar fracture (CSL group). There was no significant difference in age, gender, cause of fracture, disease duration, VAS score of neck pain, and NDI between groups ( P>0.05). However, the incidence of spinal cord injury in POA group was the highest ( P<0.05). The incidences of superior articular process fracture line posterior to the odontoid process and posterior vertebral wall fracture in POA group were the highest ( P<0.05). The incidences of vertebral arch floating and C _{2, 3} instability in IAP group were the highest ( P<0.05). There were significant differences in SAFA and VBRA between groups ( P<0.05). There was no significant difference in SAFD between groups ( P>0.05). The differences in the incidences of fracture displacement>3 mm and VBRA>5° between groups were significant ( P<0.05). There were 78 cases of unstable Hangman's fracture, including 2 cases of simple C _2、3 instability, 22 cases of simple axis rotation and displacement instability, 8 cases of simple vertebral arch floating instability, and the rest of the patients had two or more types of instability. CONCLUSION The mechanism of different subtypes of type B Hangman's fracture may be that the lateral mass of the rotation of the atlas applied the overextension compression force to the unilateral superior articular process of the axis vertebra, and the contralateral pedicle, inferior articular process and lamina fractures were caused by direct violence or/and rotational violence to different degrees. The decomposition of this type of fracture into C _{2, 3} intervertebral, axis vertebra body displacement and rotation and vertebral arch floating instability is beneficial to the treatment and surgical approach selection.
Humans ; Spinal Fractures/surgery* ; Male ; Female ; Cervical Vertebrae/diagnostic imaging* ; Middle Aged ; Adult ; Tomography, X-Ray Computed ; Aged ; Odontoid Process/injuries* ; Fracture Fixation, Internal/methods* ; Young Adult

OBJECTIVE: To observe the application of modified traction therapy in traumatic atlantoaxial subluxation in adults. METHODS: The clinical data of 31 patients with atlantoaxial subluxation treated from March 2018 to June 2019 were restropectively analyzed. There were 15 males and 16 females, aged from 18 to 68 years old with an average of 39 years old, including 10 cases of 18-40 years, 15 cases of 41-60 years, 6 cases of 51-68 years. The main manifestations of the patients were limited neck movement, pain, and atlantoaxial CT scan showed different degrees of atlantoaxial subluxation. Three dimensional multifunctional traction bed was used for traction for 2 min, relaxation for 10 s. The traction angle starts from the rearward extension of 5°-10° and weight from 3-6 kg. The weight increased by 1 kg every two days until the symptoms were improved. Traction time was 30 min twice a day and 10 days for a course of treatment. One course of treatment was performed in patients with 1-2 mm left and right equal width of atlantoaxial space, and two courses of treatment were performed in patients with 3-4 mm left and right equal width of atlantoaxial space, and the course of treatment could be increased to 3 months in especially patients with serious problems, such as 4 mm left and right equal width of atlantoaxial space and no improvement after conventional treatment. The criteria to evaluate the clinical effect was cure:no pain in the neck, normal range of neck movement, CT showed normal atlantoaxial space and odontoid process was in the middle, patients with normal neck movement were followed up 1 month after the end of treatment;improvement:neck pain was significantly improved and CT showed that the left and right atlantoaxial space was less than 1 mm in equal width. RESULTS: Among the 31 patients, 17 cases were cured by one course of treatment, 11 cases were cured by 2 courses of treatment, and 2 caseswere improved. CONCLUSION The modified traction therapy has obvious effect on adult traumatic atlantoaxial subluxation, especially the subluxation of 3-4 mm equal width in left and right atlantoaxial space, and this method is safe and reliable with good efficacy and the patients without discomfort.
Adolescent ; Adult ; Aged ; Atlanto-Axial Joint ; Female ; Humans ; Joint Dislocations ; Male ; Middle Aged ; Odontoid Process ; Spinal Fusion ; Traction ; Young Adult

OBJECTIVE: To assess the clinical results of one stage temporary atlantoaxial segmental fixation and reduction for Grauer type IIB dens fractures in teenagers. METHODS: From February 2009 to April 2015, 19 teenagers with Grauer type IIB dens fractures not amenable to anteiror screw fixation were enrolled and treated using one stage temporary atlantoaxial segmental fixation and reduction without fusion. There were 14 males and 5 females, aged from 14 to 32 years with an average of (24.6±5.0 ) years. The internal fixation was removed after bone healing confirmed by CT scan. At the last follow-up (at least 1 year after internal fixation removal), dynamic CT was used to assess the atlantoaxial rotation activity. Visual analogue scale (VAS) was recorded before the first operation, before the second operation (removal of internal fixation) and at the last follow-up. Neck Disability Index(NDI) was used to evaluate the efficacy before the second operation (removal of internal fixation) and the last follow-up. RESULTS: After operation, 2 patients developed the symptoms of occipital nerve stimulation such as numbness and pain in the occipitocervical region, and were treated with drugs such as dehydration and neurotrophic drugs, and the symptoms were relieved after 1 to 2 months. All the internal fixations were removed and all the patients were followed up more than 1 year, with time ranging from 18 to 25 months and an average of (21.47±2.41) months. The time of bone fusion after operation was 6 to 10 months with the mean of(8.21±1.27) months. Secondary surgical removal of internal fixation were performed immediately after fracture healing without internal fixation failure. The symptoms of neck pain improved significantly after operation, VAS score decreased from 6.74±0.65 before operation to 0.42±0.51 at the last follow-up after the second operation (removal of internal fixation), with statistically significant differences(<0.01). The NDI value decreased from (10.58±2.04)% before the second operation (removal of internal fixation) to (3.79±2.23)% at the last follow-up after the second operation (removal of internal fixation), with statistically significant difference(<0.01). At the last follow-up after the second operation (removal of internal fixation), dynamic CT showed that the unilateral rotation of the atlantoaxial spine reached (15.73±5.57)° to the left, (15.55±5.78)° to the right, and the overall rotation of the atlantoaxial spine was (31.28±10.71)°. CONCLUSIONS One stage temporary atlantoaxial segmental fixation and reduction for the treatment of Grauer type IIB dens fractures not amenable to anteiror screw fixation in teenagers can avoid the loss of atlantoaxial rotation function caused by atlantoaxial fusion, and to some extent retain the rotation activity of atlanto-axial joint.
Adolescent ; Adult ; Atlanto-Axial Joint ; Bone Screws ; Female ; Fracture Fixation, Internal ; Fractures, Bone ; Humans ; Male ; Odontoid Process ; Treatment Outcome ; Young Adult

Trigeminal neuralgia is caused by compression of trigeminal nerve root and it leads to demyelination gradually. It was almost idiopathic and occurred unexpected. The upper cervical spinal cord contains the spinal trigeminal tract and nucleus. Fibers with cell bodies in the trigeminal ganglion enter in the upper pons and descend caudally to C2 level. We experienced a rare patient with facial pain, which was paroxysmal attack with severe pain after a clear event, cervical spinal injury (C2). So, this case reminds us of a possible cause of trigeminal neuralgia after a trauma of the head and neck.
Cell Body ; Cervical Cord ; Demyelinating Diseases ; Facial Pain ; Head ; Humans ; Neck ; Odontoid Process ; Pons ; Spinal Cord ; Spinal Injuries ; Trigeminal Ganglion ; Trigeminal Nerve ; Trigeminal Neuralgia

Torticollis is an abnormal, asymmetric head or neck position which usually caused by imbalance of paracervical muscles. The traumatic torticollis can be caused by following events; atlantoaxial rotatory subluxation, atlantoaxial dislocation, cervical vertebral fractures, and injury to the cervical musculature. Especially, acute traumatic atlantoaxial rotatory subluxation usually presents limitation of cervical range of motion without pain or neurologic deficit. We report a case of a 58 year-old man who developed the acute atlantoaxial rotatory subluxation right after the chiropractic therapy, which induced the limitation of cervical range of motion to 52.5% of normal range. The magnetic resonance image revealed the facture of the odontoid process and the partial injury in transverse ligaments of the atlas. He underwent intramuscular botulinum toxin injection and 10 days of continuous cervical traction 15 hours a day using a 5 kg weight. The range of the cervical motion restored up to 90.2% of normal range.
Atlanto-Axial Joint ; Botulinum Toxins ; Chiropractic ; Dislocations ; Head ; Ligaments ; Muscles ; Neck ; Neurologic Manifestations ; Odontoid Process ; Range of Motion, Articular ; Reference Values ; Torticollis ; Traction

STUDY DESIGN: Prospective study. PURPOSE: To assess the prevalence of periodontoid calcification and its associations with acute cervical pain. OVERVIEW OF LITERATURE: Calcium pyrophosphate dihydrate (CPPD) deposition disease is a common rheumatological disorder that occurs especially in elderly patients. Although CPPD crystals induce acute arthritis, these crystals are not usually symptomatic. Calcification surrounding the odontoid process (periodontoid calcification) has been reported to induce inflammation, resulting in acute neck pain. This disease is called crowned dens syndrome. Whether calcification induces inflammation or whether the crystals are symptomatic remains unclear. METHODS: The prevalence of periodontoid calcification at the atlas transverse ligament was examined by computed tomography of the upper cervical spine in patients suspected of brain disease but no cervical pain (control group, n=296), patients with pseudogout of the peripheral joints but no cervical pain (arthritis group, n=41), and patients with acute neck pain (neck pain group, n=22). Next, the correlation between the prevalence of periodontoid calcification and symptoms was analyzed. RESULTS: In the control group, 40 patients (13.5%) showed periodontoid calcification with no significant difference in the prevalence with gender. The prevalence of calcification increased significantly with age (p=0.002). In the arthritis group, 26 patients (63.4%) reported periodontoid calcification. In the neck pain group, 14 patients (63.6%) reported periodontoid calcification. Multiple logistic regression analysis by age and group revealed that higher age, inclusion in the arthritis group, and inclusion in the neck pain group significantly affected the prevalence of calcification. CONCLUSIONS: Our results cumulatively suggest that periodontoid calcification is an aging-related reaction and that calcification per se does not always cause neck pain. Periodontoid calcification was observed more frequently in patients with pseudogout of the peripheral joints and in those with acute neck pain than in asymptomatic control patients.
Aged ; Arthritis ; Brain Diseases ; Calcium Pyrophosphate ; Chondrocalcinosis ; Crowns ; Humans ; Inflammation ; Joints ; Ligaments ; Logistic Models ; Neck Pain ; Odontoid Process ; Prevalence ; Prospective Studies ; Spine

Crowned dens syndrome (CDS) is a cause of neck pain characterized by calcium deposition in the periodontoid tissues. Clinical features of the syndrome are acute onset of neck pain and headache with fever. Computed tomographic imaging is necessary for diagnosis. The prognosis of CDS is excellent. Symptoms disappear within several weeks and calcifications may be absorbed. We report a case of CDS with acute onset of severe neck pain, facial pain, and pharyngeal pain provoked by swallowing.
Calcium ; Crowns* ; Deglutition ; Diagnosis ; Facial Pain ; Fever ; Headache ; Neck Pain* ; Neck* ; Odontoid Process ; Prognosis

OBJECTIVE: Anterior odontoid screw fixation is a safe and effective method for the treatment of odontoid fractures. The surgical technique is recommended for perforation of the apical cortex of the dens by the lag screw. However, overpenetration of the apical cortex may lead to potentially serious complications such as damages of adjacent vascular and neural structures. The purpose of this study was to assess the role of three-dimensional computed tomography (CT) scan to evaluate the safe margin beyond dens tip to ventral dura for anterior odontoid screw fixation.METHODS: We retrospectively analyzed the three-dimensional CT scans of the cervical spines in 55 consecutive patients at our trauma center. The patients included 38 males and 17 females aged between 22 and 73 years (mean age±standard deviation, 45.8±14.2 years). Using sagittal images of 3-dimensional CT scan, the safe margins beyond dens tip to ventral dura as well as the appropriate screw length were measured.RESULTS: The mean width of the apical dens tip was 9.6±1.1 mm. The mean lengths from the screw entry point to the apical dens tip and posterior end of dens tip were 39.2±2.6 mm and 36.6±2.4 mm. The safe margin beyond apical dens tip to ventral dura was 7.7±1.7 mm. However, the safe margin beyond the posterior end of dens tip to ventral dura was decreased to 2.1±3.2 mm, which was statistically significant (p < 0.01). There were no significant differences of safe margins beyond dens tip to ventral dura with patient gender and age.CONCLUSION: Extension by several millimeters beyond the dens tip is safe, if the trajectory of anterior odontoid screw is targeted at the apical dens tip. However, if the trajectory of the screw is targeted to the posterior end of dens tip, extension beyond dens tip may lead to damage immediately adjacent to the vental dura mater.
Bone Screws ; Dura Mater ; Female ; Humans ; Male ; Methods ; Odontoid Process ; Retrospective Studies ; Spinal Fractures ; Spine ; Tomography, X-Ray Computed ; Trauma Centers

Developmental anomalies of the axis are commonly encountered, especially anomalies involving the odontoid process. Anomalies of the posterior elements are uncommon. We describe a unique case of agenesis of posterior elements of C2 with basilar invagination and atlanto-axial dislocation. An obese 8-year-old boy presented with symptoms of cervical myelopathy. Radiological workup revealed a craniovertebral junction anomaly with occipitalised atlas, absent posterior elements of axis, and hypertrophied C3 spinous process. Atlanto-axial instability and basilar invagination was present. Magnetic resonance angiography revealed hypoplastic left vertebral artery. Traction with cervical tongs failed to improve the alignment and symptoms. Anterior trans-oral release, followed by posterior decompression and custom-made instrumentation, was done. The patient recovered completely and was asymptomatic at the end of two years. X-ray and computed tomography scan demonstrated reduction of basilar invagination and maintenance of alignment. This is the first case to be reported of agenesis of posterior elements of axis associated with basilar invagination. One should look for this condition in patients with hypertrophied spinous process of C3. Utilization of hypoplastic pedicle of axis serves as an additional fixation point to increase the stability of the construct.
Axis, Cervical Vertebra ; Child ; Decompression ; Dislocations* ; Humans ; Magnetic Resonance Angiography ; Male ; Odontoid Process ; Spinal Cord Diseases ; Spine* ; Traction ; Vertebral Artery

Calcium pyrophosphate dihydrate crystal deposition disease is associated with an acute mono- or pauciarthritis, termed "pseudogout" in elderly patients, involving a large joint (including the knees, ankles) or a chronic arthropathy manifesting as mild joint pain and stiffness. Pseudogout is a crystal-deposition disease of peripheral joints, usually encountered in elderly patients. However, acute presentation of pseudogout around the odontoid process comprises a "crowned-dens" appearance, and requires contemplation of differential diagnoses. We recently experienced a case of pseudogout in the cervical spine presenting with fever and acute neck pain that was successfully treated with a colchicine and low-dose oral steroid. We reported this case with a review of the relevant literature.
Aged ; Arthralgia ; Calcium Pyrophosphate ; Chondrocalcinosis* ; Colchicine ; Diagnosis, Differential ; Fever ; Humans ; Joints ; Knee ; Neck Pain ; Neck* ; Odontoid Process ; Spine