Shaofeng Chen1, Bo Li1, Shu Liu1, Jian Zhao2, Xiaoyi Zhou1, Xiao Zhai1, Xiaochuan Gu1, Canglong Hou1, Zhicai Shi1, Yushu Bai3, Ming Li4, Ningfang Mao5. 1. Department of Orthopaedic Surgery, Changhai Hospital, The Navy Military Medical University, Second Military Medical University, 168 Changhai Road, Shanghai, 200433, China. 2. Department of Neurology, The General Hospital of Western Theater Command, Chengdu, China. 3. Department of Orthopaedic Surgery, Changhai Hospital, The Navy Military Medical University, Second Military Medical University, 168 Changhai Road, Shanghai, 200433, China. Spinebaiys@163.com. 4. Department of Orthopaedic Surgery, Changhai Hospital, The Navy Military Medical University, Second Military Medical University, 168 Changhai Road, Shanghai, 200433, China. limingspine@126.com. 5. Department of Orthopaedic Surgery, Changhai Hospital, The Navy Military Medical University, Second Military Medical University, 168 Changhai Road, Shanghai, 200433, China. maonf@163.com.
Abstract
PURPOSE: The short rod technique (SRT) is a novel method for lumbar pedicle screw placement to reduce surgical trauma and avoid damage to the facet joint and articular surface. The core concept is to change the entry point and angle of the screw on the vertebrae at both ends in the sagittal plane to shorten the length of the longitudinal rods. The purpose of this study is to determine the sagittal screw angle (SSA) and its safe Maximum (MAX) value on each lumbar vertebra for the SRT and to observe the shortening effect on the longitudinal rods. METHODS: A total of 152 healthy adults were investigated by measuring the lumbar spine lateral view images. The SSA and MAX-SSA were measured with SRT as reference to the conventional placement technique method. The distance between the entry points of the proximal and distal vertebrae was measured to compare the changes in the length of the longitudinal rods using the two screw placement techniques. RESULTS: + SSA increased from L1 to L4, and -SSA increased from L2 to L5, in which the -SSA of L2, L3, and L4 were significantly greater than those of + SSA (P < 0.05). + MAX-SSA at L1-L4 was 23.26 ± 3.54°, 23.68 ± 3.37°, 24.12 ± 3.29°, and 24.26 ± 3.42°, respectively. -MAX-SSA at L2-L5 was 36.25 ± 3.26°, 38.26 ± 3.73°, 38.62 ± 3.63° and 37.33 ± 3.31°, respectively. Theoretical reductions by calculation for the 2-segment lumbar pedicles were: L1-2: 9 mm, L2-3: 9.29 mm, L3-4: 6.23 mm, and L4-5: 7.08 mm; And the 3-segment lumbar pedicles were: L1-3: 16.97 mm, L2-4: 16.73 mm, L3-5, and 18.24 mm, respectively. CONCLUSIONS: The application of the SRT to lumbar pedicles is a safe screw placement method that can significantly shorten the length of the used longitudinal rods.
PURPOSE: The short rod technique (SRT) is a novel method for lumbar pedicle screw placement to reduce surgical trauma and avoid damage to the facet joint and articular surface. The core concept is to change the entry point and angle of the screw on the vertebrae at both ends in the sagittal plane to shorten the length of the longitudinal rods. The purpose of this study is to determine the sagittal screw angle (SSA) and its safe Maximum (MAX) value on each lumbar vertebra for the SRT and to observe the shortening effect on the longitudinal rods. METHODS: A total of 152 healthy adults were investigated by measuring the lumbar spine lateral view images. The SSA and MAX-SSA were measured with SRT as reference to the conventional placement technique method. The distance between the entry points of the proximal and distal vertebrae was measured to compare the changes in the length of the longitudinal rods using the two screw placement techniques. RESULTS: + SSA increased from L1 to L4, and -SSA increased from L2 to L5, in which the -SSA of L2, L3, and L4 were significantly greater than those of + SSA (P < 0.05). + MAX-SSA at L1-L4 was 23.26 ± 3.54°, 23.68 ± 3.37°, 24.12 ± 3.29°, and 24.26 ± 3.42°, respectively. -MAX-SSA at L2-L5 was 36.25 ± 3.26°, 38.26 ± 3.73°, 38.62 ± 3.63° and 37.33 ± 3.31°, respectively. Theoretical reductions by calculation for the 2-segment lumbar pedicles were: L1-2: 9 mm, L2-3: 9.29 mm, L3-4: 6.23 mm, and L4-5: 7.08 mm; And the 3-segment lumbar pedicles were: L1-3: 16.97 mm, L2-4: 16.73 mm, L3-5, and 18.24 mm, respectively. CONCLUSIONS: The application of the SRT to lumbar pedicles is a safe screw placement method that can significantly shorten the length of the used longitudinal rods.
Authors: Andrew J Kanawati; Renan J R Fernandes; Aaron Gee; Jennifer Urquhart; Parham Rasoulinejad; Chris S Bailey Journal: Clin Anat Date: 2020-08-26 Impact factor: 2.414
Authors: Brandon Petrone; Joseph Albano; Robert Stockton; Aaron M Atlas; Courtney Aronica; Kanwarpaul Grewal Journal: Int J Spine Surg Date: 2021-04-01
Authors: Joseph Albano; Jonathon Lentz; Robert Stockton; Vincent DePalma; Michael Markowitz; Maximillian Ganz; Gus Katsigiorgis; Kanwarpaul Grewal Journal: Asian Spine J Date: 2019-01-29