Eijiro Okada1, Toshitaka Yoshii2, Tsuyoshi Yamada2, Kei Watanabe3, Keiichi Katsumi3, Akihiko Hiyama4, Masahiko Watanabe4, Yukihiro Nakagawa5, Motohiro Okada5, Teruaki Endo6, Yasuyuki Shiraishi6, Kazuhiro Takeuchi7, Shunji Matsunaga8, Keishi Maruo9, Kenichiro Sakai10, Sho Kobayashi11, Tetsuro Ohba12, Kanichiro Wada13, Junichi Ohya14, Kanji Mori15, Mikito Tsushima16, Hirosuke Nishimura17, Takashi Tsuji18, Atsushi Okawa2, Morio Matsumoto19, Kota Watanabe20. 1. Dept. of Orthopaedic Surgery, Keio University, Tokyo, Japan; Dept. of Orthopaedic Surgery, Saiseikai Central Hospital, Tokyo, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 2. Dept. of Orthopaedic Surgery, Tokyo Medical and Dental University, Tokyo, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 3. Dept. of Orthopaedic Surgery, Niigata University Medical and Dental General Hospital, Niigata, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 4. Dept. of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, Kanagawa, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 5. Dept. of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 6. Dept. of Orthopaedic Surgery, Jichi Medical University, Tochigi, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 7. Dept. of Orthopaedic Surgery, National Hospital Organization Okayama Medical Center, Okayama, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 8. Dept. of Orthopaedic Surgery, Imakiire General Hospital, Kagoshima, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 9. Dept. of Orthopedic Surgery, Hyogo College of Medicine, Hyogo, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 10. Dept. of Orthopaedic Surgery, Saiseikai Kawaguchi General Hospital, Saitama, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 11. Dept. of Orthopaedic Surgery, Hamamatsu University School of Medicine, Shizuoka, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 12. Dept. of Orthopaedic Surgery, University of Yamanashi, Yamanashi, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 13. Dept. of Orthopaedic Surgery, Hirosaki University Graduate School of Medicine, Aomori, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 14. Dept. of Orthopaedic Surgery, The University of Tokyo, Tokyo, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 15. Dept. of Orthopaedic Surgery, Shiga University of Medical Science, Shiga, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 16. Dept. of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, Aichi, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 17. Dept. of Orthopaedic Surgery, Tokyo Medical University, Tokyo, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 18. Dept. of Orthopaedic Surgery, Fujita Health University, Aichi, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 19. Dept. of Orthopaedic Surgery, Keio University, Tokyo, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. 20. Dept. of Orthopaedic Surgery, Keio University, Tokyo, Japan; Japanese Organization of the Study for Ossification of Spinal Ligament (JOSL), Tokyo, Japan. Electronic address: watakota@gmail.com.
Abstract
BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) increases the spine's susceptibility to unstable fractures that can cause neurological deterioration. However, the detail of injury is still unclear. A nationwide multicenter retrospective study was conducted to assess the clinical characteristics and radiographic features of spinal fractures in patients with DISH. METHODS: Patients were eligible for this study if they 1) had DISH, defined as flowing ossification along the anterolateral aspect of at least four contiguous vertebral bodies, and 2) had an injury in the ankylosing spine. This study included 285 patients with DISH (221 males, 64 females; mean age 75.2 ± 9.5 years). RESULTS: The major cause of injury was falling from a standing or sitting position; this affected 146 patients (51.2%). Diagnosis of the fracture was delayed in 115 patients (40.4%). Later neurological deterioration by one or more Frankel grade was seen in 87 patients (30.5%). The following factors were significantly associated with neurological deficits: delayed diagnosis (p = 0.033), injury of the posterior column (p = 0.021), and the presence of ossification of the posterior longitudinal ligament (OPLL) (p < 0.001). The majority of patients (n = 241, 84.6%) were treated surgically, most commonly by conventional open posterior fixation (n = 199, 69.8%). Neurological improvement was seen in 20.0% of the conservatively treated patients, and in 47.0% of the patients treated surgically. CONCLUSIONS: Minor trauma could cause spinal fractures in DISH patients. Delayed diagnosis, injury of the posterior column, and the presence of OPLL were significantly associated with neurological deterioration. Patients with neurological deficits or unstable fractures should be treated by fixation surgery.
BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) increases the spine's susceptibility to unstable fractures that can cause neurological deterioration. However, the detail of injury is still unclear. A nationwide multicenter retrospective study was conducted to assess the clinical characteristics and radiographic features of spinal fractures in patients with DISH. METHODS:Patients were eligible for this study if they 1) had DISH, defined as flowing ossification along the anterolateral aspect of at least four contiguous vertebral bodies, and 2) had an injury in the ankylosing spine. This study included 285 patients with DISH (221 males, 64 females; mean age 75.2 ± 9.5 years). RESULTS: The major cause of injury was falling from a standing or sitting position; this affected 146 patients (51.2%). Diagnosis of the fracture was delayed in 115 patients (40.4%). Later neurological deterioration by one or more Frankel grade was seen in 87 patients (30.5%). The following factors were significantly associated with neurological deficits: delayed diagnosis (p = 0.033), injury of the posterior column (p = 0.021), and the presence of ossification of the posterior longitudinal ligament (OPLL) (p < 0.001). The majority of patients (n = 241, 84.6%) were treated surgically, most commonly by conventional open posterior fixation (n = 199, 69.8%). Neurological improvement was seen in 20.0% of the conservatively treated patients, and in 47.0% of the patients treated surgically. CONCLUSIONS: Minor trauma could cause spinal fractures in DISH patients. Delayed diagnosis, injury of the posterior column, and the presence of OPLL were significantly associated with neurological deterioration. Patients with neurological deficits or unstable fractures should be treated by fixation surgery.