caa a22 4500 445834455 CHVBK 20180317145326.0 cr unu---uuuuu 170323e20110501xx s 000 0 eng 10.1007/s00586-010-1611-7 doi (NATIONALLICENCE)springer-10.1007/s00586-010-1611-7 Atlanto-axial joint of atlanto-axial subluxation patients due to rheumatoid arthritis before and after surgery, morphological evaluation using CT reconstruction [Elektronische Daten] [Yasunori Sorimachi, Haku Iizuka, Tsuyoshi Ara, Masahiro Nishinome, Yoichi Iizuka, Takashi Nakajima, Kenji Takagishi] This study investigated the preoperative morphology and postoperative fusion of the atlanto-axial joint (AAJ) in patients with atlanto-axial subluxation (AAS) due to rheumatoid arthritis (RA) using computed tomography (CT). Furthermore, we examined the relationship between the preoperative morphology of AAJ and other radiographic results. Thirty patients with AAS due to RA treated by C1-2 transarticular screw fixation (TSF) were reviewed. The morphology of the AAJ was evaluated using sagittal reconstruction views on CT before and 1year after surgery. Thereafter, the atlanto-dental interval (ADI) value at the neutral and maximal flexion position and atlanto-axial angle (AAA) at the neutral position was assessed in preoperative lateral cervical radiographs. The preoperative morphology of the AAJ on CT reconstruction views was graded as follows: Grade 1 showed maintenance of the joint space, Grade 2 showed the joint space narrowing and Grade 3 showed the destructive abnormality of subchondral bone. After surgery, the ADI value at the neutral position was assessed in lateral cervical radiographs. Furthermore, the fusion in the AAJ was investigated using CT sagittal reconstruction views taken 1year after surgery. The preoperative CT image of the AAJ demonstrated Grade 1 in 12 cases (Group A), Grade 2 in 9 cases (Group B) and Grade 3 in 9 cases (Group C). There was no significant difference in age, gender and duration of RA among the three groups. The average ADI value at the flexion position was 11.0mm in Group A, 12.3mm in Group B and 12.7mm in Group C (p>0.313). The average ADI value at the neutral position before surgery was 4.5mm in Group A, 7.3mm in Group B and 11.4mm in Group C (p<0.003). The mean AAA value was 20.8° in Group A, 21.8° in Group B and 8.4° in Group C (p<0.033). The average ADI value after TSF was 1.7mm in Group A, 2.1mm in Group B and 3.0mm in Group C (p>0.144). Fusion in the AAJ 1year after surgery was demonstrated in 14 cases (46.7%; Group A, 0 case; Group B, 5 cases; Group C, 9 cases). According to the preoperative grading of the AAJ, the postoperative fusion in the AAJ was demonstrated in 0 of 32 joints (0%) in Grade 1, 7 of 18 joints (38.9%) in Grade 2 and all of 10 joints (100%) in Grade 3. In conclusion, this study showed that a destructive abnormality of subchondral bone in the AAJ induced an enlargement of the ADI and anterior inclination of the atlas in patients with AAS due to RA. The current study also showed that fusion in the AAJ was demonstrated in 14 of 30 patients after C1/2 TSF. This was easy to recognize in AAS patients whose joint destruction extended to the subchondral bone. Springer-Verlag, 2010 Atlanto-axial subluxation nationallicence Atlanto-axial joint nationallicence Rheumatoid arthritis nationallicence Sorimachi Yasunori Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut Iizuka Haku Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut Ara Tsuyoshi Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut Nishinome Masahiro Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut Iizuka Yoichi Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut Nakajima Takashi Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut Takagishi Kenji Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut European Spine Journal Springer-Verlag 20/5(2011-05-01), 798-803 0940-6719 20:5<798 2011 20 586 https://doi.org/10.1007/s00586-010-1611-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00586-010-1611-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sorimachi Yasunori Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut NATIONALLICENCE 700 1- Iizuka Haku Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut NATIONALLICENCE 700 1- Ara Tsuyoshi Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut NATIONALLICENCE 700 1- Nishinome Masahiro Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut NATIONALLICENCE 700 1- Iizuka Yoichi Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut NATIONALLICENCE 700 1- Nakajima Takashi Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut NATIONALLICENCE 700 1- Takagishi Kenji Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22, Showa, 371-8511, Maebashi, Gunma, Japan aut NATIONALLICENCE 773 0- European Spine Journal Springer-Verlag 20/5(2011-05-01), 798-803 0940-6719 20:5<798 2011 20 586 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer