Kozo Sato1, Masakazu Kogawa2,3, Yuichiro Yamada1, Masahiro Yamashiro1, Fumio Kasama1, Michimasa Matsuda1. 1. Department of Orthopaedic Surgery, Matsuda Hospital, 17-1 Sanezawa aza Tatsutayashiki, Izumi-ku, Sendai, Miyagi, 981-3217, Japan. 2. Department of Orthopaedic Surgery, Matsuda Hospital, 17-1 Sanezawa aza Tatsutayashiki, Izumi-ku, Sendai, Miyagi, 981-3217, Japan. m.kogawa@happy.email.ne.jp. 3. Centre for Orthopaedic and Trauma Research, Discipline of Orthopaedics and Trauma, The University of Adelaide, North Terrace and George St., Adelaide, SA, 5005, Australia. m.kogawa@happy.email.ne.jp.
Abstract
INTRODUCTION: Vertebral mobility (V-mobility) has been used to diagnose fresh osteoporotic vertebral fractures (OVFs), and determine or predict bone union by setting cutoff values for these purposes. V-mobility is defined as the difference in shape of vertebral bodies between lateral radiographs taken in weight-bearing and non-weight-bearing positions. The parameters for V-mobility have varied in previous reports among anterior vertebral height (Ha, mm), wedge ratio (WR, %), and wedge angle (WA, degrees). The present study aimed to clarify WR and WA equivalent to Ha of 1.0 mm, and to compare the reported cutoff values for V-mobility presented as Ha, WR, or WA. MATERIALS AND METHODS: Lateral radiographs of 446 normal vertebrae (grade 0) and 146 deformed vertebrae (grade 1-3) from T11 to L2 were obtained from 183 female patients aged > 60 years. WR (%) values equivalent to Ha of 1.0 mm were calculated by Ha (1.0 mm)/Hp × 100 (Hp: posterior vertebral height). Corresponding WA values were calculated by trigonometric function using vertebral dimensions. RESULTS: The mean WR values equivalent to Ha of 1.0 mm in the vertebrae from T11 to L2 were 3.2%, 3.2%, 3.5%, and 3.7% for grades 0, 1, 2, and 3, respectively, and the corresponding WA values were 1.6°, 1.6°, 1.5°, and 1.4°. CONCLUSION: The equivalent values for V-mobility presented as Ha, WR, and WA were obtained. The mean WR and WA values equivalent to Ha of 1.0 mm in grade 1-3 vertebrae were 3.5% and 1.5°, respectively.
INTRODUCTION: Vertebral mobility (V-mobility) has been used to diagnose fresh osteoporotic vertebral fractures (OVFs), and determine or predict bone union by setting cutoff values for these purposes. V-mobility is defined as the difference in shape of vertebral bodies between lateral radiographs taken in weight-bearing and non-weight-bearing positions. The parameters for V-mobility have varied in previous reports among anterior vertebral height (Ha, mm), wedge ratio (WR, %), and wedge angle (WA, degrees). The present study aimed to clarify WR and WA equivalent to Ha of 1.0 mm, and to compare the reported cutoff values for V-mobility presented as Ha, WR, or WA. MATERIALS AND METHODS: Lateral radiographs of 446 normal vertebrae (grade 0) and 146 deformed vertebrae (grade 1-3) from T11 to L2 were obtained from 183 female patients aged > 60 years. WR (%) values equivalent to Ha of 1.0 mm were calculated by Ha (1.0 mm)/Hp × 100 (Hp: posterior vertebral height). Corresponding WA values were calculated by trigonometric function using vertebral dimensions. RESULTS: The mean WR values equivalent to Ha of 1.0 mm in the vertebrae from T11 to L2 were 3.2%, 3.2%, 3.5%, and 3.7% for grades 0, 1, 2, and 3, respectively, and the corresponding WA values were 1.6°, 1.6°, 1.5°, and 1.4°. CONCLUSION: The equivalent values for V-mobility presented as Ha, WR, and WA were obtained. The mean WR and WA values equivalent to Ha of 1.0 mm in grade 1-3 vertebrae were 3.5% and 1.5°, respectively.