OBJECTIVETo explore the clinical effects of cervical posterior pedicle screw internal fixation and interbody fusion for the treatment of atlanto-axial vertebral instability fractures.

METHODSFrom July 2008 to July 2013, 21 patients with atlanto-axial vertebral instability fractures were treated with vertebral pedicle screw internal fixation and interbody fusion through posterior approach. There were 14 males and 7 females, aged from 20 to 55 years old with an average of 32 years. Lifted and guided the atlanto-axial vertebral pedicle screw to reduce atlanto-axial vertebral displacement.

RESULTSAll patients were followed up from 6 to 24 months with an average of 12.5 months. Wounds got healed without complication of infection. Clinical symptoms were relieved at 6 months after operation. According to ASIA score standard to assess at 6 months after operation, the items of motion, light touch and needle score had obviously improved, and respectively were 99.45 ±0.27, 111.09 ± 0.47,111.11 ± 0.58. VAS and NDI scores also had obviously improved, and respectively were 1.04 ± 0.38 and 12.56 ± 2.24. Imaging examinations showed internal fixation locations were good, without atlanto-axial joint instability.

CONCLUSIONCervical posterior pedicle screw internal fixation and interbody fusion can effectively restore the stability of atlanto-axial joint, reduce complication and obtain satisfactory effects.

Adult ; Atlanto-Axial Joint ; injuries ; surgery ; Female ; Fracture Fixation, Internal ; methods ; Humans ; Joint Instability ; physiopathology ; surgery ; Male ; Middle Aged ; Pedicle Screws ; Spinal Fractures ; physiopathology ; surgery ; Spinal Fusion ; methods ; Young Adult

OBJECTIVETo analyze appropriate strategy about treatment of rotatory dislocation of atlantoaxial articulation in children.

METHODSFrom March 2005 to February 2009, 36 patients with rotatory dislocation of atlantoaxial articulation were retrospectively analyzed, including 25 males and 11 females, with the average age of 7.8 years (ranged 3 - 14 years). According to Fielding-Hawkins clinical classification, type I 24 cases, type II 8 cases, type III 2 cases, type IV 2 cases. All of the patients were assessed rotatory dislocation of atlantoaxial articulation and whether or not upper cervical spine malformation by X-ray, MRI and CT scan and three-dimensional reconstruction. Thirty-two cases received observational treatments which were reduction after cervical traction, without appearance of the deformity, without neurological symptoms. And another 4 serious cases (irreducible atlantoaxial dislocation or with os odontoideum) received posterior atlantoaxial fixed autograft fusion.

RESULTSRotation of atlas decreased from 16.0° ± 4.4° (range, 5° to 26°) pre-therapy to 4.5° ± 1.5° (range, 0° to 8°) post-therapy in 35 cases, rotation of atlas had significant difference between pre-therapy and post-therapy (t = 14.75, P < 0.05). One patient pre-therapy rotation of atlas was 45°, post-therapy was 4°. All patients were followed up for 14 - 38 months (mean, 18 months), 32 cases who received cervical traction and external fixation resulted in satisfactory outcome in which all the ankylodeire were disappear, bilateral masses were symmetrical on anterior-posterior and good functional activities of cervical. All the 4 cases surgically treated obtained reduction, sound bony fusion and neural symptoms were improved obviously after operation.

CONCLUSIONSConservative treatment has been proved to be very effective in most of rotatory dislocation of atlantoaxial articulation in children. However, operative treatment should be considered in the following situations: irreducible atlantoaxial dislocation or patients with os odontoideum.

Adolescent ; Atlanto-Axial Joint ; abnormalities ; physiopathology ; Child ; Child, Preschool ; Congenital Abnormalities ; Female ; Humans ; Joint Dislocations ; surgery ; therapy ; Male ; Retrospective Studies

OBJECTIVETo investigate the stability and three-dimensional movements of the atlantoaxial joint after artificial atlanto-odontoid joint (AAOJ) arthroplasty by comparing with a conventional method.

METHODSAfter anterior decompression, 24 human cadaveric spinal specimens of C0-C3 were randomly divided into two groups: Group A receiving artificial AAOJ arthroplasty; Group B experiencing anterior transarticular screw (ATAS) fixation. Two groups underwent flexibility test in intact and instrumented states. Rotational angle of the C0-C3 segments was measured to study the immediate stability and function of anterior decompression with AAOJ arthroplasty compared with the intact state and ATAS fixation.

RESULTSCompared with the intact state, anterior decompression with AAOJ arthroplasty resulted in a significant decrease in the range of motion (ROM) and neutral zone (NZ) during flexion, extension and lateral bending (P less than 0.05); however, with regard to axial rotation, there was no significant difference in ROM and NZ (P larger than 0.05). Compared with anterior decompression with ATAS fixation, anterior decompression with AAOJ arthroplasty during flexion, extension and lateral bending, significant difference was found in ROM and NZ (P larger than 0.05); however, as for axial rotation, there was a significant increase in ROM and NZ (P less than 0.05).

CONCLUSIONThe self-designed AAOJ has an excellent biomechanical performance, which can restore excellent instant stability and preserve the movement of the atlantoaxial joint.

Adult ; Arthroplasty ; methods ; Atlanto-Axial Joint ; physiopathology ; surgery ; Biomechanical Phenomena ; Bone Plates ; Bone Screws ; Cadaver ; Decompression, Surgical ; Female ; Humans ; Joint Instability ; physiopathology ; surgery ; Male ; Middle Aged ; Range of Motion, Articular ; physiology

Retropharyngeal calcific tendinitis is defined as inflammation of the longus colli muscle and is caused by the deposition of calcium hydroxyapatite crystals, which usually involves the superior oblique fibers of the longus colli muscle from C1-3. Diagnosis is usually made by detecting amorphous calcification and prevertebral soft tissue swelling on radiograph, CT or MRI. In this report, we introduce a case of this disease which was misdiagnosed as a retropharyngeal tuberculous abscess, or a muscle strain of the ongus colli muscle. No calcifications were visible along the vertical fibers of the longus colli muscle. The lesion was located anterior to the C4-5 disc, in a rheumatoid arthritis patient with atlantoaxial subluxation. Calcific tendinitis of the longus colli muscle at this location in a rheumatoid arthritis patient has not been reported in the English literature.
Adult ; Arthritis, Rheumatoid/*complications ; Atlanto-Axial Joint/*physiopathology ; Calcinosis/*complications/*diagnosis ; Diagnosis, Differential ; Dislocations/*complications ; Female ; Humans ; *Magnetic Resonance Imaging ; Pharyngeal Diseases/*complications/*diagnosis ; Tendinopathy/*complications/*diagnosis

OBJECTIVETo compare the biomechanical performances of different wires and cable fixation devices in posterior instrumentation for atlantoaxial instability, and test the effect of different fixation strengths and fixation approaches on the surgical outcomes.

METHODSSix specimens of the atlantoaxial complex (C0-C3) were used to establish models of the normal complex, unstable complex (type II odontoid fracture) and fixed complex. On the wd-5 mechanical testing machine, the parameters including the strength and rigidity of anti-rotation, change and strength of stress, and stability were measured for the normal complex, atlantoaxial instability complex, the new type titanium cable fixation system, Atlas titanium cable, Songer titanium cable, and stainless wire.

RESULTSThe strength and rigidity of anti-rotation, change and strength of stress, stability of flexion, extension and lateral bending of the unstable atlantoaxial complex fixed by the new double locking titanium cable fixation system were superior to those of the Songer or Atlas titanium cable (P<0.05) and medical stainless wire (P<0.05). Simultaneous cable fastening on both sides resulted in better fixation effect than successive cable fastening (P<0.05). Better fixation effect was achieved by fastening the specimen following a rest (P<0.05).

CONCLUSIONSThe fixation effects can be enhanced by increased fastening strengths. The new type double locking titanium cable fixation system has better biomechanical performance than the conventional Songer and Atlas titanium cables. Fastening the unstable specimens after a rest following simultaneous fastening of the specimen on both sides produces better fixation effect.

Atlanto-Axial Joint ; physiopathology ; surgery ; Biomechanical Phenomena ; Bone Wires ; Cadaver ; Humans ; Internal Fixators ; Joint Instability ; physiopathology ; surgery ; Orthopedic Fixation Devices

OBJECTIVETo explore the clinical outcomes of atlanto-axial screw-plate fixation and bone fusion for the treatment of atlanto-axial instability.

METHODSFrom June 2003 to June 2008,15 cases with atlanto-axial instability were treated with atlanto-axial lateral mass screw-plate fixation and self-cancellous bone graft fusion. There were 10 males and 5 females with the mean age of 41.7 years (range, from 19 to 72 years). Six cases were old odontoid fracture, 3 cases rheumatoid arthritis, 6 cases odontoid developmental deformity. All patients had symptoms and signs of upper cervical myelopathy and the imaging displayed atlanto-axial instability. JOA scores before operation were from 6 to 11 with an average of 7.4.

RESULTSAll patients were followed up with the mean of 28 months (range, from 9 to 40 months). The follow-up data indicated solid fusion in all patients, posterior reductions were satisfactory, no loosening or screw-plate broken was found. There were 10 cases which spinal cord function improved obviously, 4 cases improved slightly, 1 case no changed in the study. The postoperative JOA scores were from 13 to 17 with an average of 15.6.

CONCLUSIONAtlanto-axial screw-plate fixation and self-cancellous bone graft can stabilize atlas and axis, and promote fusion of atlanto-axial joint, which is an effective method for the treatment of atlanto-axial instability.

Adult ; Aged ; Atlanto-Axial Joint ; diagnostic imaging ; pathology ; physiopathology ; surgery ; Bone Screws ; Female ; Follow-Up Studies ; Fracture Fixation, Internal ; methods ; Humans ; Joint Diseases ; diagnostic imaging ; physiopathology ; surgery ; therapy ; Male ; Middle Aged ; Recovery of Function ; Spinal Fusion ; methods ; Tomography, X-Ray Computed ; Treatment Outcome

Adult ; Atlanto-Axial Joint ; surgery ; Bone Screws ; Female ; Fractures, Bone ; diagnostic imaging ; pathology ; physiopathology ; surgery ; Humans ; Male ; Middle Aged ; Odontoid Process ; injuries ; Tomography, X-Ray Computed

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

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

Atlanto-Axial Joint ; physiopathology ; Humans ; Joint Diseases ; physiopathology ; therapy ; Musculoskeletal Manipulations