K M Cheung1, D Ruan, F L Chan, D Fang. 1. Department of Orthopaedic Surgery, Queen Mary Hospital, University of Hong Kong.
Abstract
STUDY DESIGN: The lumbar pedicles of 100 adult Chinese patients were studied with computed tomography to provide data on their dimensions and angular alignment. Data obtained were compared with published measurements of spines from white patients to determine similarities and differences between the lumbar spines. SUMMARY OF BACKGROUND DATA: The age range of the patients was 18 to 60 years. There were 63 men and 37 women. There was no demonstrable sex difference for dimensions or angular alignment of the pedicles. METHODS: The method of scanning and measurement was standardized. Levels considered abnormal by the radiologist were excluded from the study, and a single observer was used to avoid inter-observer errors. The data obtained were statistically analyzed using Student's t test to determine differences between men and women and left and right sides. Age differences were analyzed using the F statistic test. The pedicle inclination angle (transverse angle) and the pedicle dimensions were compared with published data of whites. RESULTS: The pedicles of Asians, when compared with those of whites, showed a similar pattern of changes with vertebral level. However, Asian pedicles had a larger pedicle inclination angle (transverse angle) from L1 to L4 (L1 = 16 degrees, L2 = 16 degrees, L3 = 19 degrees, L4 = 23 degrees), whereas L5 (29 degrees) was similar to many series of whites. CONCLUSIONS: There are differences between the lumbar pedicles of Asians and whites. Such differences need to be considered when posterior pedicle screw fixation of the spine is performed.
STUDY DESIGN: The lumbar pedicles of 100 adult Chinese patients were studied with computed tomography to provide data on their dimensions and angular alignment. Data obtained were compared with published measurements of spines from white patients to determine similarities and differences between the lumbar spines. SUMMARY OF BACKGROUND DATA: The age range of the patients was 18 to 60 years. There were 63 men and 37 women. There was no demonstrable sex difference for dimensions or angular alignment of the pedicles. METHODS: The method of scanning and measurement was standardized. Levels considered abnormal by the radiologist were excluded from the study, and a single observer was used to avoid inter-observer errors. The data obtained were statistically analyzed using Student's t test to determine differences between men and women and left and right sides. Age differences were analyzed using the F statistic test. The pedicle inclination angle (transverse angle) and the pedicle dimensions were compared with published data of whites. RESULTS: The pedicles of Asians, when compared with those of whites, showed a similar pattern of changes with vertebral level. However, Asian pedicles had a larger pedicle inclination angle (transverse angle) from L1 to L4 (L1 = 16 degrees, L2 = 16 degrees, L3 = 19 degrees, L4 = 23 degrees), whereas L5 (29 degrees) was similar to many series of whites. CONCLUSIONS: There are differences between the lumbar pedicles of Asians and whites. Such differences need to be considered when posterior pedicle screw fixation of the spine is performed.
Authors: Keizo Sugisaki; Howard S An; Alejandro A Espinoza Orías; Richard Rhim; Gunnar B J Andersson; Nozomu Inoue Journal: Spine (Phila Pa 1976) Date: 2009-11-15 Impact factor: 3.468