Risk factors of kyphosis recurrence after implant removal in thoracolumbar burst fractures following posterior short-segment fixation.
Our aim was to evaluate the results of short-segment pedicle instrumentation with screw insertion in the fracture level and find factors predicting kyphosis recurrence in thoracolumbar burst fractures.



We retrospectively analysed 122 patients with thoracolumbar burst fracture who were divided into two groups: kyphosis recurrence and no kyphosis recurrence. Pre-operative radiographic data comprising Cobb angle (CA), regional angle, anterior vertebra height (AVH), upper intervertebral angle, vertebral wedge angle (VWA), pre-anteroposterior A/P approach, superior endplate fracture, load-sharing classification (LSC) score and clinical data including age, visual analogue scale (VAS) score, thoracolumbar injury classification and severity score were compared between groups. T test, Pearson's chi-square and multivariate logistic regression were calculated for variables.



CA, VWA and AVH were significantly corrected after surgery. CA changed from 23.7 to 3.0 (p <0.001), VWA from 38.7 to 9.6 (p <0.001) and AVH from 48.8 % to 91.2 % (p <0.001). These parameters were well maintained during the follow-up period with a mild, tolerant loss of correction. Neurological function and pain were significantly improved without deterioration. Age, pre-A/P and pre-AVH < 50 % influenced kyphosis recurrence (p = 0.032, 0.026, 0.011, respectively).



Short-segment pedicle instrumentation including the fractured vertebra was effective in treating thoracolumbar burst fractures. The loss of correction at follow-up after implant removal was associated with age, A/P ratio and anterior vertebral height < 50 %.
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Jiao-Xiang
JX
Chen
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Dao-Liang
DL
Xu
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Sun-Ren
SR
Sheng
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Amit
A
Goswami
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Jun
J
Xuan
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Hai-Ming
HM
Jin
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Jian
J
Chen
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Yu
Y
Chen
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Zeng-Ming
ZM
Zheng
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China.
Xi-Bang
XB
Chen
Department of Orthopaedic Surgery, The Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325000, China. xiangyangwangspine@126.com.
Xiang-Yang
XY
Wang
D000328:Adult; D000368:Aged; D001863:Bone Screws / Q000009:adverse effects*; D020878:Device Removal / Q000009:adverse effects; D005260:Female; D005593:Fracture Fixation, Internal / Q000379:methods*; D006801:Humans; D007738:Kyphosis / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D016103:Spinal Fractures / Q000601:surgery*; D013904:Thoracic Vertebrae / Q000601:surgery*
Anterior vertebra height; Kyphosi recurrence; Short- segment pedicle instrumentation; Thoracolumbar burst fracture