Atlanto-Axial Joint ; injuries ; surgery ; Decompression, Surgical ; Fracture Fixation, Internal ; methods ; Humans ; Joint Dislocations ; surgery ; Traction

Atlanto-Axial Joint ; injuries ; Child ; Humans ; Joint Dislocations ; etiology ; Male ; Tympanoplasty ; adverse effects

We present a case of posterior atlantoaxial screw-rod fixation in a patient with an aberrant vertebral artery (VA) course combined with bilateral high-riding VA. An aberrant VA which courses below the posterior arch of the atlas (C1) that does not pass through the C1 transverse foramen and without an osseous anomaly is rare. However, it is important to consider an abnormal course of the VA both preoperatively and intraoperatively in order to avoid critical vascular injuries in procedures which require exposure or control of the VA, such as the far-lateral approach and spinal operations.
Atlanto-Axial Joint ; Bone Screws ; Humans ; Vascular System Injuries ; Vertebral Artery

OBJECTIVESTo explore the clinical features of traumatic atlantoaxial instability combined with subaxial cervical spinal cord injury (CSCI), and to analyze the feasibility, indication and therapeutic effects of anterior-posterior approach in such cases.

METHODSFrom March 2004 to September 2009, 16 cases with this trauma were admitted and surgically treated in our department. Before surgery, skull traction was performed. Posterior atlantoaxial pedicle screw internal fixation and bone graft fusion were conducted to manage traumatic atlantoaxial instability. As for subaxial CSCI, anterior cervical corpectomy or discectomy decompression, bone grafting and internal fixation with steel plates were applied.

RESULTSAll operations were successful. The average operation time was 3 hours and operative blood loss 400 ml. Satisfactory reduction of both the upper and lower cervical spine and complete decompression were achieved. All patients were followed up for 12 to 36 months. Their clinical symptoms were improved by various levels. The Japanese Orthopaedic Association (JOA) scores ranged from 10 to 16 one year postoperatively, 13.95+/-2.06 on average(improvement rate equal to 70.10%). X-rays, spiral CT and MRI confirmed normal cervical alignments, complete decompression and fine implants'position. There was no breakage or loosening of screws, nor exodus of titanium mesh or implanted bone blocks. The grafted bone achieved fusion 3-6 months postoperatively and no atlantoaxial instability was observed.

CONCLUSIONSTraumatic atlantoaxial instability may combine with subaxial CSCI, misdiagnosis of which should be especially alerted and avoided. For severe cases, one stage anterior-posterior approach to decompress the upper and lower cervical spine, together with reposition, bone grafting and fusion, as well as internal fixation can immediately restore the normal alignments and stability of the cervical spine and effectively improve the spinal nervous function, thus being an ideal approach.

Aged ; Atlanto-Axial Joint ; injuries ; surgery ; Female ; Humans ; Joint Instability ; diagnosis ; surgery ; Male ; Middle Aged ; Spinal Cord Injuries ; diagnosis ; surgery

Atlanto-Axial Joint ; pathology ; physiopathology ; Child, Preschool ; Female ; Humans ; Joint Dislocations ; etiology ; Tomography, X-Ray Computed ; Wounds and Injuries ; complications

OBJECTIVETo discuss the therapeutic effects of the atlantoaxial pedicle screw system fixation in treatment of atlantoaxial instability.

METHODSFrom June 2003 to March 2010, 32 patients with atlantoaxial instability were treated by atlantoaxial pedicle screw system fixation, included 21 males and 11 females wiht an average age of 42.5 years old ranging from 28 to 66 years. Among them, 18 cases were odontoid process fractures, 7 were congenital dissociate odontoid process, 4 were Jefferson fracture combined with odontoid fracture, 3 were rheumatic arthritis causing atlantoaxial instability. All patients suffered from the atlantoaxial subluxation and atlantoaxial instability. The JOA score ranged from 4 to 14 (means 9.1 +/- 0.3) before operation. The patients had some image examination including the X-ray of cervical vertebrae (include of dynamic position film), spiral CT 3D reconstruction and/or MRI. The position of pedicle screw system implantation,the angle of pedicle screw system implantation and screw length were measured. Operating skull traction. Operation undewent general anesthesia, implanted the pedicle screw, reduction and bone fusion under direct vision. The bone was fixated between posterior arch of atlas and lamina of axis by the lateral combination bended to posterior.

RESULTSOne hundred and twenty-eight atlantoaxial pedicle screws were implanted in 32 patients. No patient had the injure of spinal cord, nerve root and vertebral artery. All patients were followed-up from 6 to 48 months (averaged 16 months). After operation, the JOA score ranged from 11 to 17 (averaged 15.9 +/- 0.2), improvement rate was 86.1%. The fracture of odontoid process were healing completely. All fusion bone were combinated. The internal fixation wasn't loosening and breaking.

CONCLUSIONThe atlantoaxial pedicle screw system fixation was effective method to treat atlantoaxial instability. The method had many advantages, such as provide rigid and short segment fixation, safe and simple, high fusion rate. The method was worth in clinical application.

Adult ; Aged ; Atlanto-Axial Joint ; diagnostic imaging ; injuries ; surgery ; Biomechanical Phenomena ; Bone Screws ; Female ; Humans ; Joint Instability ; surgery ; Male ; Middle Aged ; Tomography, X-Ray Computed

Adolescent ; Adult ; Atlanto-Axial Joint ; injuries ; physiopathology ; Child ; Child, Preschool ; Female ; Follow-Up Studies ; Humans ; Joint Dislocations ; physiopathology ; surgery ; therapy ; Male ; Rotation

OBJECTIVETo evaluate and compare the diagnostic value in atlantoaxial subluxation by CT three-dimensional (3D) reconstruction.

METHODS3D reconstruction findings of 41 patients with atlantoaxial subluxation were retrospectively analyzed, and comparisons were made among images of transverse section, multiplanar reformorting (MPR), surface shade display (SSD), maximum intensity project (MIP), and volume rendering (VR).

RESULTSOf 41 patients with atlantoaxial subluxation, 31 belonged to rotary dislocation, 5 antedislocation, and 5 hind dislocation. All the cases showed the dislocated joint panel of atlantoaxial articulation. Fifteen cases showed deviation of the odontoid process and 8 cases widened distance between the dens and anterior arch of the atlas. The dislocated joint panel of atlantoaxial articulation was more clearly seen with SSD-3D imaging than any other methods.

CONCLUSIONSAtlantoaxial subluxation can well be diagnosed by CT 3D reconstruction, in which SSD-3D imaging is optimal.

Adolescent ; Adult ; Aged ; Atlanto-Axial Joint ; injuries ; Child ; Female ; Humans ; Imaging, Three-Dimensional ; Joint Dislocations ; diagnostic imaging ; Male ; Middle Aged ; Retrospective Studies ; Tomography, X-Ray Computed ; methods

Antirheumatic Agents ; therapeutic use ; Arthritis, Rheumatoid ; complications ; drug therapy ; Atlanto-Axial Joint ; injuries ; Humans ; Joint Dislocations ; etiology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Syringomyelia ; diagnosis ; etiology ; physiopathology

OBJECTIVETo explore the feasibility of C1-2 pedicle screw fixation and fusion technique in treating atlantoaxial instability.

METHODSFrom January 2006 to January 2009,18 patients with atlantoaxial instability were treated with C1-2 pedicle screws and plates fixation under general anesthesia. There were 11 males and 7 females, the age for 17-62 years with the mean of 37.7 years. The course of disease was from 3 days to 30 months with an average of 10.6 months. The patients had different degrees neck pain and disturbance of sensation or (and) dyskinesia, had atlantoaxial instability from images before operation. The JOA scoring before operation were from 8 to 15 with an average of 11.4. Bone fusion of patients was observed with X-rays, CT and MR image at the same time after operation and the JOA scoring was compared with preoperative.

RESULTSA total of 72 screws were successfully placed in 18 cases, among them, 15 cases were followed up from 6 to 24 months with an average of 11.5 months. Fifteen cases obtained bone fusion with time for 3-6 months without the complications of internal fixation failure or redislocation of atlas. The spinal compression had differently improved, postoperative JOA scoring was from 12 to 17 scores with an average of 14.5 scores.

CONCLUSIONPedicle screw fixation and fusion in atlas has advantages of firm fixation and high fusion rate, it is a better choices for atlantoaxial instability. It is not suitable for variations of sulcus of vertebral artery of atlas and posterior arch of atlas.

Adolescent ; Adult ; Atlanto-Axial Joint ; injuries ; physiopathology ; surgery ; Bone Plates ; Bone Screws ; Female ; Fracture Fixation, Internal ; Humans ; Male ; Middle Aged ; Treatment Outcome ; Young Adult