Atlantoaxial rotary subluxation after minor trauma

Prediction of the functional and radiological outcome on the basis of independent factors with special emphasis on the use of 3D printed models in craniovertebral junction surgery

Background:

The aim of the study was to evaluate the advantage of performing planned surgery using customized three-dimensional (3D) printed models versus performing surgery without using 3D printed models in patients with craniovertebral junction (CVJ) anomalies and traumatic CVJ fractures and dislocations.

Methods:

Forty-two patients with CVJ anomalies, who were planned for operative intervention in the Department of Neurosurgery at SMS Hospital from March 2019 to February 2021, were randomly divided into two groups and analyzed. First group was operated after rehearsal on a customized 3D printed model whereas the second group underwent operative intervention without the rehearsal of surgery on the 3D printed model.

Results:

Forty-two patients were enrolled for the study. Twenty-five of these patients had developmental CVJ anomalies, 16 had post traumatic Atlantoaxial dislocation (AAD), and one had congenital AAD. Twenty-three patients underwent surgical intervention using 3D printed models and 19 without using 3D printed models. The outcome in the two groups was compared using modified Japanese orthopedic association score (mJOA), recovery rate, incidence of complications such as screw malposition, postoperative neurological deterioration, vertebral artery (VA) injury, and radiological improvement based on Atlanto-Dental interval, the distance of the tip of dens from Wackhenheims clivus canal line, and the distance of tip of dens from the Chamberlain’s line. The improvement in mJOA score postoperatively was found to be statistically significant in study group (P < 0.001) as compared to control group (P = 0.06). Recovery rate was better in study group than in control group (P = 0.023). In study group, the incidence of screw malposition and VA injury was lower than control group. Three patients deteriorated neurologically postoperatively in the control group and none in the study group. The average improvements in the radiological parameters were found to be better in study group as compared to control group postoperatively.

Conclusion:

The authors conclude that 3D printed models are extremely helpful in analyzing joints and VA anatomy preoperatively and are helpful in unmasking any abnormal bony and vascular anatomy effectively, making the surgeon confident about the placement of the screws intraoperatively. These 3D models help in intraoperative error minimization with better neurological outcomes in postoperative period. In our opinion, these models should be included as a basic investigation tool in patients of CVJ abnormalities. The models also offer other advantages such as preoperative simulation, teaching modules, and patient education.

C1-C2 Rotatory Subluxation in Adults “A Narrative Review”

The atlantoaxial joint C2 (axis) with the anterior arch of C1 (atlas) allows 50% of cervical lateral rotation. It is responsible for precise and important movements that allow us to perform precise actions, both in normal and working life. Due to low incidence in adults, this condition often goes undiagnosed, or the diagnosis is delayed and the outcome is worse. An early diagnosis and treatment are essential to ensure satisfactory neurological and functional outcomes. The aim of this review is to analyze C1-C2 rotatory subluxation in adults, given its rarity. The time between injury and reduction is key, as it is directly related to prognosis and the severity of the treatment options. Due to low incidence in adults, this condition often goes undiagnosed, or the diagnosis is delayed as a lot of cases are not related to a clear trauma, with a poor prognosis just because of the late diagnosis and the outcome is worse. The correct approach and treatment of atlantoaxial dislocation requires a careful study of the radiological findings to decide the direction and plane of the dislocation, and the search for associated skeletal anomalies.

Atlantoaxial Dislocation: Surgical Outcome following Anterior Retropharyngeal Approach to Odontoid with or without Fixation

Introduction Atlantoaxial dislocation (AAD) refers to a loss of stability between the atlas and axis vertebra. The conventional transoral approach and the anterior retropharyngeal approach (ARPA) are adequate for the upper cervical vertebral segments. This study was undertaken to evaluate the usefulness of the ARPA to the odontoid in patients of AAD.

Materials and Methods The study was undertaken on 20 patients admitted in Nil Ratan Sircar Medical College and Hospital, Kolkata, India, with functional disability secondary to AAD. These patients underwent surgery through ARPA to odontoid with or without fixation. Patients were analyzed between October 2014 and September 2016.

Results Maximum number of patients belonged to third decade of life. The male to female ratio was 1.5. The mean duration of symptoms was 10.86 months. Weakness of the upper and lower limbs predominated. About 65% patients had axial neck pain. Nine patients (45%) in total had difficulty in either bowel or bladder. Five patients presented with fracture odontoid and pannus formation of the odontoid process, while six had basilar invagination. One patient underwent anterior odontoid screw fixation and the other 19 patients underwent anterior retropharyngeal odontoidectomy with posterior fixation. Two patients expired in the present study. Most of the patients had improvement in Nurick grade during follow-up. Five patients had transient throat pain and dysphagia. Three patients had superficial surgical site infection. One patient had postoperative cerebrospinal fluid leak.

Conclusion The ARPA to odontoid is a feasible approach for decompression and fixation of the odontoid in AAD cases.

Atlanto-axial rotary instability (Fielding type 1): characteristic clinical and radiological findings, and treatment outcomes following alignment, fusion, and stabilization

Atlanto-axial instability (AAI) is common in the connective tissue disorders, such as rheumatoid arthritis, and increasingly recognized in the heritable disorders of Stickler, Loeys-Dietz, Marfan, Morquio, and Ehlers-Danlos (EDS) syndromes, where it typically presents as a rotary subluxation due to incompetence of the alar ligament. This retrospective, IRB-approved study examines 20 subjects with Fielding type 1 rotary subluxation, characterized by anterior subluxation of the facet on one side, with a normal atlanto-dental interval. Subjects diagnosed with a heritable connective tissue disorder, and AAI had failed non-operative treatment and presented with severe headache, neck pain, and characteristic neurological findings. Subjects underwent a modified Goel-Harms posterior C1-C2 screw fixation and fusion without complication. At 15 months, two subjects underwent reoperation following a fall (one) and occipito-atlantal instability (one). Patients reported improvement in the frequency or severity of neck pain (P < 0.001), numbness in the hands and lower extremities (P = 0.001), headaches, pre-syncope, and lightheadedness (all P < 0.01), vertigo and arm weakness (both P = 0.01), and syncope, nausea, joint pain, and exercise tolerance (all P < 0.05). The diagnosis of Fielding type 1 AAI requires directed investigation with dynamic imaging. Alignment and stabilization is associated with improvement of pain, syncopal and near-syncopal episodes, sensorimotor function, and exercise tolerance.

Atlantoaxial Rotatory Subluxation: A Rare Complication of Craniofacial Surgery

INTRODUCTION

Neck pain is common in the post-operative period after craniofacial procedures. If patients present with neck pain and torticollis, it could be a manifestation of atlantoaxial rotatory subluxlation (AARS), which describes a rare condition in which there is lateral displacement of C1 relative to C2. When this occurs in the post-operative patient, it is termed Grisel syndrome. In this case series, we report on 3 patients diagnosed with Grisel syndrome after a craniofacial procedure.

METHODS

A retrospective chart review of a single craniofacial surgeon at a pediatric hospital was conducted over the last 3 decades. Demographics, procedures performed, and management strategies of AARS were included for review.

RESULTS

Three patients were identified who were diagnosed with Grisel syndrome after a craniofacial procedure and required inpatient cervical traction. All patients presented with torticollis within 1 week of their operation. Conservative management was ineffective, and all 3 patients were admitted for inpatient cervical traction, for an average of 13 days followed by an average of 47 days of outpatient therapy. No patients showed any signs of recurrence after removal of outpatient traction device.

CONCLUSION

Grisel syndrome is a rare, but serious complication of craniofacial procedures. Physicians caring for these patients must have a high degree of suspicion if a patient with a recent craniofacial procedure presents with torticollis. Delaying the initiation of therapy has been shown to lead to higher rates of recurrence and increases the likelihood that patients will require surgical intervention.

Three-Dimensional-Printed Model-Assisted Management of Craniovertebral Junction Abnormalities: An Institutional Experience with Literature Review

Study Design

Prospective study.

Purpose

To evaluate the utility and limitations of using three-dimensional (3D)-printed models for the management of craniovertebral (CV) junction abnormalities.

Overview of Literature

In comparison to other bony and vascular anomalies, CV junction abnormalities are difficult to treat. For cases of irreducible atlantoaxial dislocation (AAD), posterior reduction and stabilization have replaced anterior decompression as the standard management protocol. The use of 3D models, such as those described herein, can provide surgeons with in-depth knowledge of the vertebral artery course and bony anomalies associated with CV junction abnormalities.

Methods

Clinical and radiological features of 18 patients with CV junction abnormalities were analyzed between March 2017 and February 2019 at Sawai Man Singh Medical College, Jaipur, India. Dynamic computed tomography (CT) of the CV junction and CT angiographies of the neck with respect to the vertebral artery course at the C1–C2 joints were obtained and studied. Customized 3D models of the CV junction were then made based on the CT data, and rehearsal of the surgical procedure was performed using the 3D model one day prior to performing the actual procedure.

Results

Seventeen patients had congenital-type AAD, whereas one patient had posttraumatic AAD. Improvements in neck pain and myelopathy were seen in all patients at the follow-up, as analyzed using the Visual Analog Scale and the Japanese Orthopedic Association Scale score, respectively. There were no cases of malpositioning of screws or any direct vertebral artery injury, although in one patient, the distal flow in the dominant vertebral artery was cut off as it got compressed between the bony arch and the screw head.

Conclusions

Compared to computer-generated images, 3D-printed models are a more practical approach for dealing with complex CV junction abnormalities. They provide surgeons with deep insights into the complex bony anomalies as well as variations in the vertebral artery courses, thereby improving surgical outcomes.

Interventional magnetic resonance imaging as a diagnostic and therapeutic method in treating acute pediatric atlantoaxial rotatory subluxation

Atlantoaxial rotatory subluxation or fixation (AARF) is a rare condition, usually occurring in pediatric patients. It mimics benign torticollis but may result in permanent disability or death. The condition requires prompt diagnosis by thorough examination to avoid any treatment delays. Spiral computed tomography (CT) with three-dimensional reconstruction CT is recommended for identifying incongruence between C1 and C2 vertebrae, and magnetic resonance imaging (MRI) may be performed to exclude ligamentous injuries. In addition to static imaging, dynamic CT involves the reduction between C1 and C2 being confirmed using CT with the head turned maximally to the left and right. The present report (level of evidence, III) provides a method for treating AARF that has similar advantages as dynamic CT but avoids ionizing radiation by replacing CT with interventional MRI. The new method comprised simultaneous axial traction and manual closed reduction, performed under general anesthesia, and the use of interventional MRI to ensure that reduction was achieved and held. The head is turned maximally to the right and left during the manual reduction. A rigid cervical collar was used following reduction. Dynamic CT was not required but prior diagnostic static CT was performed in preparation. No further CT was required. There appears to be no previous studies on interventional MRI in AARF care. Being superior in its diagnostic soft-tissue visualization performance and lacking ionizing radiation, interventional MRI is a potential option for investigating and treating acute AARF in non-syndromic patients with no trauma history.

An infantile alantoaxial dislocation with patent foramen ovale managed with titanium cabling and allogenic bone grafts

Atlantoaxial dislocation is a disorder that is characterized with loss of stability of the atlas and axis (C1-C2) with consequential loss of usual articulation. Although this condition is very common, no one has reported a case as young as our patients. We present a 7-month infant with bilateral paralysis of the lower limbs for four (4) months with no history of trauma. Computer tomographic (CT-scan) imaging revealed alantoaxial dislocation with severe cervical spinal cord compression. The odontoid process is displaced outwardly with no bone destruction. Doppler echocardiogram done revealed patent foramen ovale. Thorough physical examination as well as radiological evaluation revealed no feather malformations. Electrophysio - logical studies reveal normal compound muscle action potentials (CMAP) and sensory nerve action potentials (SNAPs) in all the limbs. Electromyography (EMG) also revealed normal nerves in the limbs and the trunk. We attained a stable fusion and anatomical reduction using a posterior titanium wire and an iliac bone graft harvested from his mother. This is the youngest patient reported in literature. Infantile alantoaxial dislocation should be managed at early stage to prevent long-term neurologic disorders.

Atlantoaxial Rotatory Subluxation in Children

OBJECTIVES

Pediatric cervical injuries are uncommon. This study was to describe injury circumstances, clinical findings, and management among children diagnosed with atlantoaxial rotatory subluxation (AARS) to aid in its recognition and management.

METHODS

Subanalysis of a large case-control study from January 2000 to December 2004 in 17 hospitals in the Pediatric Emergency Care Applied Research Network was performed. Cases were children younger than 16 years with AARS after blunt trauma (n = 55); controls were (a) children with other cervical spine injuries (other CSI, n = 485) and (b) those with normal imaging of the cervical spine (non-CSI, n = 1060).

RESULTS

Children with AARS were younger (mean [SD] age, 7.7 [3.8] vs 10.7 [4.6]; Wilcoxon P < 0.01). Falls accounted for 36% of injuries; there were no diving mechanisms (vs other CSI, falls 19%, Fisher exact P < 0.01, and diving 7%, P = 0.04). Children with AARS sought medical care more than 24 hours after the injury event (21% vs 1% for non-CSI controls, P < 0.01). Clinical findings associated with AARS included neck pain (67%) and torticollis (57%) versus other CSI, pain (47%) and torticollis (5%, P < 0.01) for each, and versus non-CSI controls, pain (33%) and torticollis (6%, P < 0.01) for each. Management of AARS included no intervention (n = 6, 11%), soft or rigid collar only (n = 24, 44%), traction (n = 14, 25%), halo (n = 9, 16%), internal fixation (n = 2, 4%), and varied across institutions (P = 0.02).

CONCLUSIONS

Children with AARS often have a delayed presentation with neck pain and torticollis; falls are a common injury mechanism. Treatment varied across institutions. Further work is needed to identify optimal management.

Anterior Retropharyngeal Reduction and Sequential Posterior Fusion for Atlantoaxial Rotatory Fixation With Locked C1-C2 Lateral Facet

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To introduce a new type of atlantoaxial rotatory fixation (AARF) with a locked C1-C2 lateral facet and evaluate its therapeutic strategy.

SUMMARY OF BACKGROUND DATA

AARF presenting with torticollis and limited neck motion is commonly seen in teenagers. Fielding and Hawkins' classification is generally applied to AARF. Although conservative treatment is effective for acute AARF, it is often unsuccessful for chronic AARF, which ultimately requires surgery. We introduce a new type of chronic AARF with a locked C1-C2 lateral facet that does not fit into Fielding and Hawkins' classification and describe the appropriate treatment.

METHODS

Eight patients who had chronic AARF with a unilaterally locked C1-C2 lateral facet were referred to our clinic. Reduction had failed after traction for 3 to 4 weeks. After open release and reduction using the anterior retropharyngeal approach, we applied posterior C1-C2 transpedicular screw fixation with an autologous iliac bone graft for stage I or II.

RESULTS

The anterior retropharyngeal approach provided direct access to the C1-C2 locked lateral facet. The patient in an overall poor condition (stage II) underwent delayed posterior C1-C2 arthrodesis. The others (stage I) underwent immediate posterior C1-C2 arthrodesis. All patients were followed up for an average of 14.8 months (5-37 mo). Three-dimensional computed tomography revealed C1-C-2 arthrodesis bone graft fusion after an average of 3.1 months (2-4 mo). There was no recurrence of symptoms and no dislocations or internal fixation device loosening or breakage.

CONCLUSION

AARF with a locked C1-C2 lateral facet is a new type of AARF that cannot be classified using Fielding and Hawkins' classification. The anterior retropharyngeal approach for the release and reduction of AARF, followed by posterior C1-C2 arthrodesis is an effective therapeutic strategy for AARF with a locked C1-C2 lateral facet.

LEVEL OF EVIDENCE

4.

Atlantoaxial rotatory subluxation in children

Atlantoaxial rotatory subluxation is a rare condition in which patients present with the acute onset of torticollis. Atlantoaxial rotatory subluxation represents a spectrum of disease from muscle spasm to a fixed mechanical block to reduction of the atlantoaxial complex. If left untreated, some cases may resolve spontaneously; however, other cases may result in the development of secondary changes in the bony anatomy of the atlantoaxial joint, leading to persistent deformity. Diagnosis of the condition is largely clinical but can be aided by various imaging modalities, including radiographs, dynamic CT scanning, three-dimensional CT reconstructions, or MRI. Consideration should always be given to infection or other inflammatory disease as an underlying, precipitating cause. Treatments include observation, the use a cervical collar and analgesics, halter or skeletal traction, and posterior fusion of C1-C2. The most important factor for success of conservative treatment is the time from the onset of symptoms to recognition and the initiation of treatment.

A review of the diagnosis and treatment of atlantoaxial dislocations

Study Design Literature review. Objective Atlantoaxial dislocation (AAD) is a rare and potentially fatal disturbance to the normal occipital-cervical anatomy that affects some populations disproportionately, which may cause permanent neurologic deficits or sagittal deformity if not treated in a timely and appropriate manner. Currently, there is a lack of consensus among surgeons on the best approach to diagnose, characterize, and treat this condition. The objective of this review is to provide a comprehensive review of the literature to identify timely and effective diagnostic techniques and treatment modalities of AAD. Methods This review examined all articles published concerning "atlantoaxial dislocation" or "atlantoaxial subluxation" on the PubMed database. We included 112 articles published between 1966 and 2014. Results Results of these studies are summarized primarily as defining AAD, the normal anatomy, etiology of dislocation, clinical presentation, diagnostic techniques, classification, and recommendations for timely treatment modalities. Conclusions The Wang Classification System provides a practical means to diagnose and treat AAD. However, future research is required to identify the most salient intervention component or combination of components that lead to the best outcomes.

Atlantoaxial rotatory subluxation as a cause of torticollis in a 5-year-old girl

Many patients present to the emergency department complaining of a sore or stiff neck and lateral flexion of the neck with contralateral rotation. Under the pressure of the breaching time and busy shifts some of the patients are discharged to the care of their general practitioners without adequate investigations. While most of the cases are due to benign causes, torticollis can be due to many congenital and acquired pathologies, some of which may need further investigation and urgent management. Atlantoaxial subluxation (AAS), tumours of the base of the skull and infections are among these causes. Delayed diagnosis may lead to worsening neurology and complicate the management. We report a case of a 5-year-old girl who presented to our fracture clinic with a fractured clavicle and torticollis; her subsequent investigations confirmed the diagnosis of AAS. Our patient responded to non-operative treatment and improved with no neurological complications.

Not your typical torticollis: a case of atlantoaxial rotatory subluxation

A 9-year-old boy was pushed while carrying a heavy backpack. He had no fall or direct trauma to his neck. After a few hours from the incident, he presented with neck pain and torticollis. However, somewhat atypical for torticollis, he was not able to rotate his face to the neutral position. There were no neurological deficits. Concerned by his inability to rotate his neck, the clinician suggested CT of the upper cervical spine, which demonstrated rotary subluxation of the atlantoaxial junction. The patient was taken to the operating theatre. Reduction was performed under general anaesthesia. He did well and was back to school in the following days.

Effect of rehabilitation on a child with atlantoaxial rotatory fixation

STUDY DESIGN

Case report.

OBJECTIVE

To discuss a case of atlantoaxial rotatory fixation (AARF) successfully treated with manual therapy.

SUMMARY OF BACKGROUND DATA

A 9-year-old girl experienced acute torticollis and neck stiffness after a traffic accident. Image studies revealed AARF, a cause of pediatric torticollis. She received closed reduction with the aid of C-arm fluoroscopy under general anesthesia. She was referred to the researchers' rehabilitation clinic because of unsolved torticollis and limited head rotation. At her initial visit, we found that her head tilted to the right and rotated to the left. Tenderness and muscle guarding over the right suboccipital region were also apparent. The first manual therapy significantly improved neck motion after soft tissue release applying to the suboccipital muscle group.

METHODS

We arranged for her to enter a rehabilitation program including (1) soft tissue release technique to the suboccipital muscle group for 10 minutes and (2) muscle energy technique for neck flexion, extension, lateral bending, and rotation for 10 to 15 minutes.

RESULTS

After 3 months' rehabilitation, her symptoms of torticollis, neck pain, and limited range of motion achieved near-total recovery.

CONCLUSION

This case report presents the association between suboccipital muscles and AARF, suggesting that the soft tissue release of suboccipital muscle group may facilitate recovery from AARF. More studies are needed to verify the inferences of this case report.

Atlantoaxial rotatory fixation--a cause of torticollis

BACKGROUND

A rare, but important cause of torticollis in children is atlantoaxial rotatory fixation. If the patient remains undiagnosed for more than three months, surgery is generally the only therapeutic alternative. In this article we present our experiences of surgical treatment of late-diagnosed atlantoaxial rotatory fixation in children.

MATERIAL AND METHOD

This article is based on a review of the case notes of patients who underwent surgery for atlantoaxial rotatory fixation in the Department for Neurosurgery at Oslo University Hospital, Rikshospitalet, during the period 2004-10.

RESULTS

The material sample consists of six children aged from seven to 14 years. Five had suffered minor trauma to the upper neck region, while one had had an upper respiratory tract infection. The diagnosis was made 5-36 months after the onset of symptoms. In three of the patients, an attempt was made at closed reduction without success. A CT scan one year postoperatively showed a normal position of the atlantoaxial joint in two patients and partial reduction in three. In the sixth patient there was bone fusion at the time of the operation, and open reduction was unsuccessful. All six patients had reduced rotational movement of the neck at the one-year check-up.

INTERPRETATION

All our patients were diagnosed more than five months after the onset of symptoms. Full or partial reduction was achieved in five of the six.

Torticollis

Torticollis refers to a twisting of the head and neck caused by a shortened sternocleidomastoid muscle, tipping the head toward the shortened muscle, while rotating the chin in the opposite direction. Torticollis is seen at all ages, from newborns to adults. It can be congenital or postnatally acquired. In this review, we offer a new classification of torticollis, based on its dynamic qualities and pathogenesis. All torticollis can be classified as either nonparoxysmal (nondynamic) or paroxysmal (dynamic). Causes of nonparoxysmal torticollis include congenital muscular; osseous; central nervous system/peripheral nervous system; ocular; and nonmuscular, soft tissue. Causes of paroxysmal torticollis are benign paroxysmal; spasmodic (cervical dystonia); Sandifer syndrome; drugs; increased intracranial pressure; and conversion disorder. The description, epidemiology, clinical presentation, evaluation, treatment, and prognosis of the most clinically significant types of torticollis follow.

Utility of plain radiographs in detecting traumatic injuries of the cervical spine in children

OBJECTIVE

The objective of this study was to estimate the sensitivity of plain radiographs in identifying bony or ligamentous cervical spine injury in children.

METHODS

We identified a retrospective cohort of children younger than 16 years with blunt trauma-related bony or ligamentous cervical spine injury evaluated between 2000 and 2004 at 1 of 17 hospitals participating in the Pediatric Emergency Care Applied Research Network. We excluded children who had a single or undocumented number of radiographic views or one of the following injuries types: isolated spinal cord injury, spinal cord injury without radiographic abnormalities, or atlantoaxial rotary subluxation. Using consensus methods, study investigators reviewed the radiology reports and assigned a classification (definite, possible, or no cervical spine injury) as well as film adequacy. A pediatric neurosurgeon, blinded to the classification of the radiology reports, reviewed complete case histories and assigned final cervical spine injury type.

RESULTS

We identified 206 children who met inclusion criteria, of which 127 had definite and 41 had possible cervical spine injury identified by plain radiograph. Of the 186 children with adequate cervical spine radiographs, 168 had definite or possible cervical spine injury identified by plain radiograph for a sensitivity of 90% (95% confidence interval, 85%-94%). Cervical spine radiographs did not identify the following cervical spine injuries: fracture (15 children) and ligamentous injury alone (3 children). Nine children with normal cervical spine radiographs presented with 1 or more of the following: endotracheal intubation (4 children), altered mental status (5 children), or focal neurologic findings (5 children).

CONCLUSIONS

Plain radiographs had a high sensitivity for cervical spine injury in our pediatric cohort.

Atlantoaxial rotary subluxation after tympanoplasty

OBJECTIVE

To describe a case of the atlantoaxial rotary subluxation (AARS) after tympanoplasty and discuss its mechanism and management.

PATIENTS

A 10-year-old boy.

INTERVENTIONS

Cervical spine plain radiography followed by cervical traction.

MAIN OUTCOME MEASURES

Range of motion and radiologic follow-up.

RESULTS

The patient showed painful torticollis and rotation and fixation of the head to the right side (cock robin sign). Increased atlantodens interval and asymmetry between facet joints were found on cervical plain radiography. Full functional recovery and reduction of subluxation were achieved by conservative cervical traction.

CONCLUSION

Forced surgical positioning of head rotation to the contralateral ear down and restriction during otologic surgery under general anesthesia may complicate AARS, especially in pediatric otologic surgery patients.