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World Neurosurg 2019 Feb 16. Epub 2019 Feb 16.

Sklifosovsky Research Institute of Emergency Care, Moscow, Russia; A.I. Evdokimov Moscow Medical University.

Purpose: To perform a radiological analysis of the degeneration of C1-C2 joints following C1-C2 transarticular fixation (TAF), and compare the long-term results of a routine Magerl technique (RMT) to a posterior transarticular С1-С2 stand-alone screw instrumentation (SAS) application.

Materials And Methods: Forty patients (26 men and 14 women) were included in this retrospective observational cohort study. The mean follow-up period was 61. Read More

PM R 2018 Nov 28. Epub 2018 Nov 28.

Division of Neurosurgery, University of Missouri School Medicine, Columbia, MO 65212.

Individuals with spinal cord injury (SCI) have altered neurophysiology and present with symptoms that must be interpreted in the context of their specific neurologic injury. This is a case of a 16-year-old female adolescent with C5 American Spinal Injury Association Impairment Scale A SCI who presented with intractable nausea. Multiple etiologies for her nausea, including medication effect, metabolic and gastrointestinal disorders, autonomic dysreflexia, and mood disorder, were systematically ruled out. Read More

J Neurosurg Spine 2019 Feb 15:1-9. Epub 2019 Feb 15.

2Department of Neurosurgery, Division of Pediatric Neurosurgery, University of Utah, Primary Children's Hospital, Salt Lake City, Utah.

OBJECTIVEThere is contradictory evidence regarding the relative contribution of the key stabilizing ligaments of the occipitoatlantal (OA) joint. Cadaveric studies are limited by the nature and the number of injury scenarios that can be tested to identify OA stabilizing ligaments. Finite element (FE) analysis can overcome these limitations and provide valuable data in this area. Read More

Eur Spine J 2019 Feb 13. Epub 2019 Feb 13.

Department of Orthopaedic Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, People's Republic of China.

Purpose: The Anterior Atlantoaxial Non-Fusion Fixation System (AANFS) was a novel motion preservation device for atlantoaxial instability to replace traditional fusion techniques. The purpose of this in vivo study was to evaluate the clinical features and biomechanical properties of this new device in a canine model by comparing it with a conventional method.

Methods: Eighteen adult male canines were randomly divided into group 1, which received the AANFS replacement, group 2 which received the Harms rigid fixation procedures, and group 3, which served as the control group. Read More

J Neurosurg Sci 2019 Feb 4. Epub 2019 Feb 4.

Department of Neurosurgery and Gamma Knife Radiosurgery, I.R.C.C.S. San Raffaele Scientific Institute, Vita-Salute University, Milan, Italy.

J Neurosurg Spine 2019 Jan 25:1-4. Epub 2019 Jan 25.

Departments of1Neurosurgery and.

The authors present a case report of a patient discovered to have a rotatory subluxation of the C1-2 joint and a large retroodontoid pannus with an enhancing lesion in the odontoid process eventually proving to be caused by gout. This patient represented a diagnostic conundrum as she had known prior diagnoses of not only gout but also sarcoidosis and possible rheumatoid arthritis, and was in the demographic range where concern for an oncological process cannot fully be ruled out. Because she presented with signs and symptoms of atlantoaxial instability, she required posterior stabilization to reduce the rotatory subluxation and to stabilize the C1-2 instability. Read More

Pediatr Neurosurg 2019 Jan 24:1-9. Epub 2019 Jan 24.

Children's Hospital of Los Angeles, Los Angeles, California, USA.

Background/aims: Down syndrome is the most common inherited disorder. Some patients develop atlantoaxial instability. Existing screening guidelines were developed prior to availability of MRI. Read More

Asian Spine J 2019 Jan 24. Epub 2019 Jan 24.

Department of Orthopedic Surgery, Busan Korea Hospital, Busan, Korea.

Study Design: Retrospective case analysis.

Purpose: We hypothesized that larger the C1-C2 fusion angle, greater the severity of the sagittal malalignment of C0-C1 and C2- C7.

Overview Of Literature: In our experience, instances of sagittal malalignment occur at C0-C1 and C2-C7 following atlantoaxial fusion in patients with Os odontoideum (OO). Read More

Spine Deform 2019 Mar;7(2):298-303

Servicio de Patología Espinal, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, CABA, Buenos Aires, Argentina.

Study Design: Descriptive retrospective cohort of 52 pediatric patients with mucopolysaccharidosis (MPS) and spinal cord disease and surgical outcomes in a reference hospital.

Objectives: To describe clinical manifestations and surgical management and outcomes of spinal lesions.

Methods: All medical records of 52 patients with mucopolysaccharidosis (I, II, III, IV, and VI) diagnosed between 1992 and 2011 were identified and followed at a single spine center of a pediatric hospital. Read More

Neurospine 2018 Oct 2. Epub 2018 Oct 2.

Department of Neurosurgery, Tokyo Women's Medical University, Tokyo, Japan.

Introduction: It is difficult to treat atlanto-axial instability in cases with high riding vertebral artery or anomalies of craniocervical junction. We report two successful cases with trans-spinal canal screwing technique because of difficulty to perform conventional fixation methods. Case presentation. Read More

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 2019 Jan;33(1):35-40

Operating Room, West China Hospital, Sichuan University, Chengdu Sichuan, 610041,

Objective: To assess the application and the effectiveness of a strategy of combining posterior occipitocervical angle (POCA) with occipital-C (O-C ) angle for adjustment of occipitocervical fixation angle in posterior instrumented occipitocervical fusion.

Methods: The clinical data of 22 patients undergoing posterior instrumented occipitocervical fusions between March 2013 and January 2016 were retrospectively analysed, and all patients were performed by using a strategy combining with POCA and O-C angle for adjustment of occipitocervical fixation angle. All patients suffered from occipitocervical instability, including 7 males and 15 females with an average age of 44. Read More

Acta Neurochir Suppl 2019 ;125:279-288

, New York, USA.

Background: In children, when unresponsive neck rigidity and distress are observed after ear, nose and throat (ENT) surgical treatment or nasopharyngeal inflammation, Grisel's syndrome should be suspected. This is a rare syndrome involving non-traumatic rotatory subluxation of the atlantoaxial joint. Conservative management with external cervical orthoses and empirical antibiotic, muscle relaxant and analgesic therapy should be the first choice of treatment. Read More

Acta Neurochir Suppl 2019 ;125:259-264

Department of Neurological Surgery, Policlinico "Gaspare Rodolico" University Hospital, Catania, Italy.

Background: A retro-odontoid pseudotumour compressing the spinal cord and causing myelopathy is often associated with an inflammatory condition such as rheumatoid arthritis. A degenerative non-inflammatory retro-odontoid pseudotumour responsible for clinically relevant spinal cord compression is a rare condition described in small clinical series and is likely associated with craniovertebral junction hypermobility or instability-like conditions. For several years, direct removal of the lesion through an anterior or lateral approach has been advocated as the best surgical option. Read More

Acta Neurochir Suppl 2019 ;125:101-110

Department of Neurosurgery, KEM Hospital and Seth GS Medical College, Mumbai, India.

Aim: In this paper we evaluate the role of atlantoaxial instability in the pathogenesis of Chiari formation type I and the role of atlantoaxial stabilization for treatment of this condition in cases with no obvious bone malformation in the region of the craniovertebral junction.

Materials, Methods And Results: During the period from January 2010 to July 2016, we identified 57 cases of Chiari formation where there was no bone malformation or evidence of craniovertebral junction instability that could be diagnosed on the basis of an abnormal increase in the atlantodental interval on dynamic imaging. Forty-eight of these patients had syringomyelia. Read More

Acta Neurochir Suppl 2019 ;125:79-86

Department of Experimental Biomedicine and Clinical Neurosciences, School of Medicine, Neurosurgical Clinic, University of Palermo, Palermo, Italy.

Rheumatoid arthritis (RA) is a chronic inflammatory disorder, characterized by polyarticular inflammation causing progressive joint damage and disability. The mechanisms underlying its pathogenesis involve activation of innate and adaptive immunity, microvascular endothelial cell activation, and inflammatory infiltration of lymphocytes and monocytes into the synovium. Spinal involvement in RA is not typical; when it occurs, the main radiological features are (1) atlantoaxial subluxation (AAS), which is the most typical form of cervical spine involvement; (2) cranial settling-also known as basilar impression, atlantoaxial impaction or superior migration of the odontoid-which is the most severe form of associated spinal instability; and (3) subaxial subluxation. Read More

Acta Neurochir Suppl 2019 ;125:71-78

Department of Neurosurgery, Seth GS Medical College and KEM Hospital, Mumbai, India.

Aim: In this paper the role of atlantoaxial and multilevel subaxial spinal instability as the primary nodal point of the pathogenesis of degenerative cervical spinal disease-related myelopathy, and the focus of surgical treatment for it, is evaluated.

Materials And Methods: The series analyses the treatment of 73 patients with single or multilevel degenerative cervical spinal disease by fixation of the involved spinal segment(s) alone, aimed at arthrodesis. No bone decompression or disc/osteophyte resection was done. Read More

Acta Neurochir Suppl 2019 ;125:63-70

Department of Neurosurgery, Seth GS Medical College and KEM Hospital, Mumbai, India.

Background: This paper reviews an experience of surgically treating ossification of the posterior longitudinal ligament (OPLL) with fixation of the involved spinal segments alone, without resorting to any bony or soft tissue decompression or attempts at direct resection of the OPLL. While in the early part of the experience, stabilization of only the involved subaxial cervical spinal segments was done, in the later part of the experience, atlantoaxial fixation was included in the multisegmental spinal fixation construct. This treatment is based on the understanding that spinal instability that includes atlantoaxial instability forms the nodal point of the pathogenesis and development of OPLL, and maturation of the presenting clinical symptoms. Read More

Acta Neurochir Suppl 2019 ;125:59-62

Department of Neurosurgery, King Edward VII Memorial Hospital and Seth GS Medical College, Mumbai, India.

The atlantoaxial joint is the most mobile joint in the body. The physical architecture of the joint is characterized by a uniformly round and approximately flat surface, which allows a wide range of unobstructed movements. The standing human posture and lifelong heartbeat like uninterrupted activity of the atlantoaxial joint, and its ability to facilitate saying both 'yes' and 'no' necessarily requires smooth and 'fluid' movements that are supported by strong yet supple ligaments. Read More

Medicine (Baltimore) 2019 Jan;98(1):e13780

Department of Medical Chemistry, Medical University of Vienna, Vienna, Austria.

Spondyloepiphyseal dysplasia congenita (SEDC) is an autosomal dominant disorder, characterized by disproportionate dwarfism with short spine, short neck associated with variable degrees of coxa vara. Cervical cord compression is the most hazardous skeletal deformity in patients with SEDC which requires special attention and management.Ten patients with the clinical and the radiographic phenotypes of spondyloepiphyseal dysplasia congenita have been recognized and the genotype was compatible with single base substitutions, deletions or duplication of part of the COL2A1 gene (6 patients out of ten have been sequenced). Read More

Surg Neurol Int 2018 28;9:240. Epub 2018 Nov 28.

Department of Ortho-Spine Surgery, Sir Ganga Ram Hospital, New Delhi, India.

Background: Concurrent injuries to both the odontoid and transverse atlantal ligament are rare and can be easily missed. Failure to diagnose both lesions potentially leads to the late onset of sagittal plane instability and acute myelopathy. Here, we present a patient with an odontoid fracture whose transverse atlantal ligament (TAL) injury was originally missed on magnetic resonance imaging (MRI) and computed tomography (CT) scans. Read More

J Vet Med Sci 2018 Dec 24. Epub 2018 Dec 24.

The Laboratory of Veterinary Surgery, Nippon Veterinary and Life Science University.

This study investigated cerebral ventricle size and concurrent craniocervical junction abnormality in relation to atlantooccipital overlapping (AOO) in dogs with atlantoaxial instability (AAI). A total of 61 dogs were treated with atlantoaxial ventral fixation. Medical records of each dog, including magnetic resonance (MR) and computed tomography (CT) images, were retrospectively reviewed. Read More

Case Rep Orthop 2018 15;2018:2809546. Epub 2018 Nov 15.

Department of Orthopaedic Surgery, Chiba University, Graduate School of Medicine, 1-8-1 Inohana Chuou-ku, Chiba, Chiba 260-8670, Japan.

An occipital condyle fracture (OCF) is a relatively rare trauma that is now increasingly diagnosed because of the wide availability of computed tomography. For nondisplaced OCFs, conservative treatment is generally recommended, and there is no previous report of a nondisplaced OCF requiring surgery. We report a patient who had a nondisplaced OCF with craniocervical misalignment (a condyle-C1 interval > 2. Read More

Neurospine 2018 Dec 19;15(4):323-328. Epub 2018 Dec 19.

Department of Neurosurgery, K.E.M. Hospital and Seth G.S. Medical College, Parel, Mumbai, India.

The author reviews the various types of cervical fusion that are associated with instability of the craniovertebral junction. Assimilation of the atlas, C2-3 fusion, the Klippel-Feil abnormality, and pancervical fusion are amongst the more common types of bone abnormalities. It is conceptualised that these types of cervical fusion are not related to any kind of embryological dysgenesis or fault, but instead emerge due to longstanding muscle spasms of the neck in response to atlantoaxial instability. Read More

J Neurosurg Spine 2018 Dec 14:1-9. Epub 2018 Dec 14.

4Department of Neurological Surgery, University of California, Davis, Sacramento, California.

OBJECTIVEC1-2 is a highly mobile complex that presents unique surgical challenges to achieving biomechanical rigidity and fusion. Posterior wiring methods have been largely replaced with segmental constructs using the C1 lateral mass, C1 pedicle, C2 pars, and C2 pedicle. Modifications to reduce surgical morbidity led to the development of C2 laminar screws. Read More

Eur Spine J 2019 Feb 11;28(2):362-369. Epub 2018 Dec 11.

Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, No. 76 Linjiang Road, Yuzhong District, Chongqing, 400010, People's Republic of China.

Purpose: To investigate the anatomical and biomechanical feasibility of the unilateral C1 double screw [pedicle screw (PS) + lateral mass screw (LMS)] and ipsilateral C2 PS combined with contralateral C2 laminar screw (LS)-rod fixation for atlantoaxial instability by comparison with traditional posterior fixation methods.

Methods: Fifteen sets of complete dry bony specimens of atlas were used for morphometric analysis. The working length, width and thickness of the C1 PSs and LMSs were manually measured. Read More

J Forensic Leg Med 2019 Feb 29;61:92-96. Epub 2018 Nov 29.

Department of Legal Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba city, Chiba Prefecture, 260-8670, Japan; Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.

A 5-year-old boy with a chromosome-9 abnormality and multiple external and visceral malformations was found in cardiopulmonary arrest during a regular visit to the hospital; he did not respond to cardiopulmonary resuscitation and died. An odontoid process fracture and calcification and fibrosis of the muscles around the superior cervical vertebra were observed during the autopsy. Postmortem computed tomography revealed an anterior dislocation of the atlas; odontoid synchondrosis fracture; and delayed, incomplete bony fusion of the odontoid process relative to his age. Read More

Kaohsiung J Med Sci 2018 Dec 19;34(12):700-704. Epub 2018 Sep 19.

Spinal Surgery Unit, Shengjing Hospital of China Medical University, Shenyang, PR China. Electronic address:

Atlanto-axial instability (AAI) is a congenital or developmental condition that leads to instability/subluxation of the atlantoaxial joint. This study is performed to determine anatomic feasibility of trajectory L and help select an optimal screw trajectory in treating patients with AAI with a narrow C1 posterior arch. Sixty patients who underwent cervical three dimensional-computed tomography (3D-CT) were chosen from the hospital's picture archiving and communication system (PACS). Read More

Asian Spine J 2018 Dec 7. Epub 2018 Dec 7.

Department of Orthopedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Korea.

Study Design: Retrospective case analysis.

Purpose: We retrospectively evaluated the clinical and radiological outcomes of posterior sublaminar wiring (PSLW) and/or transarticular screw fixation (TASF) for reducible atlantoaxial instability (AAI) secondary to os odontoideum.

Overview Of Literature: Limited information is available about the surgical outcomes of symptomatic os odontoideum with AAI. Read More

Vet Comp Orthop Traumatol 2019 Jan 28;32(1):33-40. Epub 2018 Nov 28.

Department of Clinical Veterinary Medicine, Clinical Radiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.

Objective:  The main purpose of this study was to define criteria to systemically describe craniovertebral junction (CVJ) anomalies and to report the prevalence of CVJ anomalies in small breed dogs with and without atlantoaxial instability (AAI).

Materials And Methods:  Retrospective multicentre matched case-control study evaluating magnetic resonance imaging and computed tomographic images of small breed dogs with and without AAI for the presence of CVJ anomalies.

Results:  One hundred and twenty-two dogs were enrolled (61 with and 61 without AAI). Read More

J Clin Neurosci 2018 Nov 21. Epub 2018 Nov 21.

Department of Anatomy, Histology and Embryology, Medical University of Innsbruck, Innsbruck, Austria.

Purpose: Atlantoxial fusion with screw rod constructs traditionally requires subperiostal dissection of the C1/C2 muscle attachments, which may lead to postoperative axial neck pain and intraoperative blood loss. We evaluate a potentially less invasive, muscle splitting approach for atlantoaxial fusion in a cadaver model.

Methods: A technical feasibility study was performed in a human cadaveric specimen with standard surgical instruments and an operating microscope. Read More

World Neurosurg 2019 Feb 22;122:e1511-e1518. Epub 2018 Nov 22.

Department of Orthopedics, Peking University Third Hospital, Beijing, China.

Objective: Atlantoaxial stabilization procedures in high-riding vertebral artery (HRVA) cases are challenging. C2 translaminar screws are rigid and pose no risk to the vertebral artery. The aim of this study was to present clinical outcomes of atlantoaxial dislocation combined with HRVA using C2 translaminar screws. Read More

Eur Spine J 2018 Nov 17. Epub 2018 Nov 17.

Department of Orthopedic Surgery, Orthopedic Hospital of Xingtai, Xingtai, 054000, Hebei, China.

Background: Atlantoaxial dislocation usually results from hyperextension trauma and is almost always accompanied by odontoid fracture and neurological symptoms. In most cases, patients with atlantoaxial dislocation die instantly. This is a rare report of posterior atlantoaxial dislocation without fracture and neurological symptoms effectively treated by transoral-posterior approach surgery, and only eleven similar cases have been previously reported. Read More

J Craniovertebr Junction Spine 2018 Jul-Sep;9(3):205-208

Department of Orthopaedics, Lokmanya Tilak Municipal Medical College and General Hospital, Sion, Mumbai, Maharashtra, India.

Giant cell tumor (GCT) or osteoclastoma is a benign, locally aggressive tumor with a tendency to recur. Involvement of the axial skeleton is very rare and majority of them are seen in the sacrum. The authors report a rare case of a 19-year-old female who presented with a C2 dens GCT with a pathological fracture and atlantoaxial dislocation. Read More

Z Rheumatol 2018 Dec;77(10):889-895

Klinik für Neurochirurgie, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81679, München, Deutschland.

In addition to involvement of small peripheral joints, the cervical spine is the second most affected body region in rheumatoid arthritis (RA). Due to improvement of pharmaceutical treatment in recent years, new data show that there is a decreasing prevalence of cervical involvement; however, depending on the severity of cervical lesions surgical treatment still plays an important role. The sequelae of involvement of the cervical spine are craniocervical and atlantoaxial instability, which can cause severe pain, neural deficits and even death. Read More

Zh Vopr Neirokhir Im N N Burdenko 2018 ;82(5):111-118

Priorov National Medical Research Center of Traumatology and Orthopedics, Moscow, Russia.

Treatment of patients with atlantoaxial instability caused by various diseases of the skull base and craniovertebral junction combined with ventral compression of the brainstem is a complex issue that is ambiguously resolved in different ways. We present a case of stepped treatment, the most important component of which was successful transoral removal of an aggressive aneurysmal bone cyst of the CII vertebra with anterior CI-CIII segment stabilization using an individual system, which was performed through the same approach.

Clinical Case: A 31-year-old male patient presented with destruction of the CII body and odontoid process affected by an aggressive aneurysmal bone cyst causing disintegration of the CII posterior wall and odontoid process, which clinically manifested by constricted motion and pain in the cervical spine. Read More

World Neurosurg 2019 Feb 4;122:583-589. Epub 2018 Nov 4.

Department of Orthopaedic Surgery, Spine Center, Changzheng Hospital, Second Military Medical University, Shanghai, China. Electronic address:

Background: Atlantoaxial instability owing to bone erosions in a patient with ankylosing spondylitis (AS) is rare. We describe the radiographic characteristics, pathology, and treatment of a patient with this rare clinical manifestation and review the literature.

Case Description: A 36-year-old man with an 8-year history of AS presented with progressive neck pain, low back pain, hand numbness, and limited mobility of the neck. Read More

Case Rep Radiol 2018 30;2018:1658129. Epub 2018 Sep 30.

Department of Imaging and Medical Information Sciences, Division of Radiology, Geneva University Hospitals, Geneva, Switzerland.

Retroodontoid pseudotumor (ROP) is a nonneoplasic lesion of unknown etiology, commonly associated with inflammatory conditions, and the term of pannus is usually used. Less frequently, ROP formation can develop with other noninflammatory entities, with atlantoaxial instability as most accepted pathophysiological mechanism for posttraumatic or degenerative ROP. As it can clinically and radiologically mimic a malignant tumor, it is paramount for the radiologist to know this entity. Read More

World Neurosurg 2019 Jan 10;121:e908-e916. Epub 2018 Oct 10.

Department of Neurosurgery, K.E.M. Hospital and Seth G.S. Medical College, Parel, Mumbai, India.

Objective: The implications of diagnosis and treatment of central or axial atlantoaxial dislocation (CAAD) as a cause of symptoms of cervical myelopathy are evaluated.

Methods: This is a report of a series of 5 patients who presented with the primary symptoms of spasticity and motor weakness and paresthesias in all the limbs. There was no evidence of any significant compression of the dural tube or neural structures at the craniovertebral junction. Read More

World Neurosurg 2019 Jan 11;121:100-110. Epub 2018 Oct 11.

San Diego Center for Spinal Disorders, La Jolla, California, USA.

Background: Retro-odontoid pseudotumor (RP) can be caused by several diseases, especially rheumatoid arthritis, and is usually associated with the presence of atlantoaxial instability. On the other hand, a different group of patients have been identified in whom RP is observed without radiologic findings of atlantoaxial instability. The pathophysiology, clinical characteristics, and prognosis of this latter group of patients are not well described in the literature. Read More

World Neurosurg 2019 Jan 9;121:59-61. Epub 2018 Oct 9.

Department of Radiodiagnosis, PGIMER, Chandigarh, India.

Background: An anomalous vertebral artery is not a deterrent for posterior C1-C2 joint manipulation and reduction of atlantoaxial dislocation (AAD). However, presence of an incidental aneurysm in the aberrant segment of artery with concurrent AAD adds to the surgical challenge.

Case Description: A 30-year-old woman presented with neck pain and spastic quadriparesis. Read More

Int J Pediatr Otorhinolaryngol 2018 Nov 27;114:36-43. Epub 2018 Aug 27.

Department of Otolaryngology, Hospital for Sick Children, Toronto, ON, Canada; Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, University of Toronto, Toronto, ON, Canada. Electronic address:

Purpose: Children with trisomy 21 are at a greater risk for craniocervical junction instability than the general population. These children frequently require administration of anesthesia due to surgical (including otolaryngological) interventions and are at risk for neurological injury. We reviewed the current literature describing iatrogenic neurological injury in children with trisomy 21 undergoing anesthesia in order to facilitate the development of safety recommendations. Read More

Am J Vet Res 2018 Oct;79(10):1079-1086

OBJECTIVE To retrospectively evaluate the epidemiological and morphological features and outcome of surgical treatment of incomplete ossification of the dorsal neural arch of the atlas (IODA) in dogs with atlantoaxial instability (AAI). ANIMALS 106 AAI-affected dogs that underwent ventral fixation of the atlantoaxial joint. PROCEDURES Medical records and CT images for each dog were reviewed. Read More

World Neurosurg 2019 Jan 22;121:e296-e301. Epub 2018 Sep 22.

Department of Neurosurgery, K.E.M. Hospital and Seth G.S. Medical College, Parel, Mumbai, India.

Objective: Voice alteration as a presenting symptom in cases with Chiari formation is analyzed, as well as outcome after atlantoaxial fixation.

Methods: During the period January 2016 to June 2017, 25 cases of Chiari formation presented with associated or a major presenting symptom of voice or speech quality alteration related to inadequate breathing efforts. All patients underwent atlantoaxial fixation. Read More

Spine (Phila Pa 1976) 2018 Sep 17. Epub 2018 Sep 17.

Orthopaedic Biomechanics Laboratory, VA Long Beach Healthcare System, Long Beach and Department of Orthopaedic Surgery, University of California, Irvine, CA, USA.

Study Design: A biomechanical in vitro study using human cadaveric spines.

Objective: To compare atlantoaxial stability and stiffness of a C1 lateral mass - C2 short pedicle - C3 lateral mass screw-rod construct versus C1 lateral mass - C2 pedicle screw-rod construct.

Summary Of Background Data: The C1 lateral mass - C2 pedicle screw-rod construct provides excellent atlantoaxial fixation but C2 pedicle screw placement is associated with risk of vertebral artery injury. Read More

Spine (Phila Pa 1976) 2019 Mar;44(5):E306-E314

Department of Spine Surgery, Center for Orthopedics, Daping Hospital, Army Medical University.

Detailed clinical information of 13 adult patients with acute atlantal fractures underwent nonoperative treatment was retrospectively studied. "Rule of Spence" was found inaccurate in predicting either integrity of transverse atlantal ligament (TAL) or atlantoaxial stability, whereas Dickman's classification of TAL injury was more superior to "rule of Spence" on both prediction.

Study Design: A retrospective study. Read More

Int Orthop 2018 Sep 14. Epub 2018 Sep 14.

Spine Surgery Unit, Surgery and Transplantations Department, Ospedale Pediatrico Bambino Gesù, Rome, Italy.

Purpose: Mucopolysaccharidosis (MPS) are rare inherited metabolic diseases, causing lysosomal storage of mucopolysaccharides; clinical presentation involves skeletal system and particularly the spine. Anomalies include developing kyphosis at thoracolumbar junction, that can causes nervous symptoms, and dens hypoplasia with associated atlantoaxial subluxation that can cause myelopathy. We present our experience in the treatment of spine pathology in MPS. Read More

World Neurosurg 2019 Jan 11;121:e70-e76. Epub 2018 Sep 11.

Department of Neurosurgery, General Hospital of People's Liberation Army, Beijing, China. Electronic address:

Objective: Upper cervical fixation with C2 pedicle screw insertion may predispose patients to vertebral artery injury, in particular, patients with craniovertebral junction anomalies. The aim of this study was to describe an alternative technique with trans-C2 inferior articular process screw (C2IAPS) insertion for rigid C2 fixation, which can be used to anchor the C2 vertebra for upper cervical fixation.

Methods: Records of 19 patients who underwent posterior atlantoaxial fixation using C2IAPS combined with C1 lateral mass screw were retrospectively reviewed. Read More

Am J Intellect Dev Disabil 2018 Sep;123(5):387-398

Meghan E. O'Neill, Alexandra Ryan, Soyang Kwon, and Helen J. Binns, Ann & Robert H. Lurie Children's Hospital of Chicago.

The American Academy of Pediatrics's guideline on health supervision for children with Down syndrome (DS) offers pediatricians guidance to improve detection of comorbid conditions. Pediatrician adherence has not yet been comprehensively evaluated. Medical records of 31 children with DS who received primary care at two urban academic clinic sites from 2008-2012 were reviewed. Read More

World Neurosurg 2018 Dec 24;120:e453-e456. Epub 2018 Aug 24.

Spine Center, the Department of Orthopedics, the 117th Hospital of PLA, Hangzhou, Zhejiang, China. Electronic address:

Objective: We sought to develop a new posterior fusion technique composed of bilateral C1 titanium cables and C2 pedicle screw-rods for treatment of atlantoaxial instability not suitable for C1 screw placement.

Methods: A study was conducted of 18 patients with atlantoaxial instability who had C1 broken screw trajectory or anatomic anomalies. All patients underwent posterior fixation with bilateral C1 titanium cables and C2 pedicle screws. Read More