Part III. Prediction of Lumbar Disc Bulging or Protrusion Based on
Chapter 6 Conclusion
B. Conference papers
Risk Factors and Prevalence of Musculoskeletal Disorder among Nursing Personnel in Taiwan: Results of a Questionnaire Survey. Premus 2007 Sixth International Scientific Conference on Prevention of Work-Related
Musculoskeletal Disorder, Boston, USA, Aug 27-31, 2007(Poster Presentation)
Dose-response relationship with occupational herniated intervertebral disc (HIVD) in Taiwan. Conference of 41th Asia-Pacific Academic Consortium for Public Health (APACPH), Dec 4-6, 2009, Taipei, Taiwan. (Poster Presentation)
Occupational herniated intervertebral disc (HIVD) in Taiwan-physical,
occupational and genetic interaction. Conference of 41th Asia-Pacific Academic Consortium for Public Health (APACPH), Dec 4-6, 2009, Taipei, Taiwan. (Poster Presentation)
Prevalence and Risk Factors for Musculoskeletal Discomfort among Nurses in Taiwan.The 21nd International Conference on Epidemiology in Occupational Health (EPICOH), Apr 21-25, 2010, Taipei, Taiwan. (Oral Presentation)
The gene-work exposure interaction in causing occupational HIVD. The 21nd International Conference on Epidemiology in Occupational Health (EPICOH), Apr 21-25, 2010, Taipei, Taiwan. (Poster Presentation)
The gene-work exposure interaction in causing occupational HIVD in Taiwan.
Premus 2010 Seventh International Scientific Conference on Prevention of Work-Related Musculoskeletal Disorder,2010, August 29~September 3, Angers, France. (Oral Presentation)
Association of COL11A1 with lumbar disc degeneration (LDD) in Taiwan young adults：The 21st Asian Conference on Occupational Health, Fukuoka, Japan.Sep 2-4. (Poster Presentation)
List of Tables
Part I. Dose-Response Relationship between Lumbar Disc Degeneration and Life Time Cumulative Lifting Load
Table 1.Demographic characteristics of the study participants Variables
15–30 132 (33.7) 77 (48.1) 209 (37.9)
> 30 175 (44.6) 33 (20.6) 208 (37.7)
Education Level
Junior high and below 164 (42.4) 31 (19.6) 195 (35.8)
Senior high school 197 (50.9) 57 (36.1) 254 (46.6)
College or above 26 (6.7) 70 (44.3) 96 (17.6)
Lifetime cumulative lifting load (Newton × hours, Nh) by tertiles Low lifting exposure
55 (14.0) 123 (76.9) 185 (33.4)
(<4.0 ×105)
Intermediate lifting exposure
159 (40.5) 28 (17.5) 184 (33.3)
(4.0 ×105 – 8.9 ×106) High lifting exposure
179 (45.6) 9 (5.6) 184 (33.3)
(>8.9 ×106)
Low back pain (within 6 months) 335 (86.3) 122 (76.7) 457 (83.6)
Cigarette smoking (pack-years)
0 294 (75.8) 132 (82.5) 426 (77.7)
1–20 37 (9.5) 15 (9.4) 52 (9.5)
> 20 57 (14.7) 13 (8.1) 70 (12.8)
BMI, body mass index; SD, standard deviation
Table 2. Prevalence of disc-related degenerative findings on MRI images of the lumbar spine in the study
Degeneration sign
Intervertebral disc level
L1–L2 L2–L3 L3–L4 L4–L5 L5–S1
N (%) N (%) N (%) N (%) N (%)
Dehydration 112 (20.2) 213 (38.5) 301 (54.4) 382 (69.1) 352 (63.7)
Annulus tear 1 (0.2) 10 (1.8) 30 (5.4) 113 (20.4) 91 (17.9)
Disc height narrowing 16 (2.9) 23 (4.2) 26 (4.7) 31 (5.6) 74 (13.4)
Bulging 43 (7.8) 146 (26.4) 255 (46.1) 342 (61.8) 251 (45.4)
Protrusion 14 (2.5) 14 (2.5) 19 (3.4) 99 (17.9) 92 (16.6)
Extrusion 0 (0.0) 0 (0.0) 0 (0.0) 3 (0.5) 1 (0.2)
Sequestration 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0)
Degenerative spondylolisthesis 0 (0.0) 1 (0.3) 14 (2.5) 61 (11.0) 11 (2.0) Spondylolytic spondylolisthesis 0 (0.0) 0 (0.0) 0 (0.0) 3 (0.5) 15 (2.7)
Foramina narrowing 0 (0.0) 6 (1.1) 21 (3.8) 74 (13.4) 65 (11.8)
Nerve root compression 0 (0.0) 0 (0.0) 5 (0.9) 16 (2.9) 22 (4.0)
Table 3. The association between disc degeneration and life-time lifting exposure ( Newton × hours , Nh) among upper lumbar level$
$ Adjusted for age, gender, BMI and smoking (pack-yr)
* Statistically significant, p< .05
@ Statistically significant after Bonferroni correction, p< .0083 OR, odds ratios; AOR, adjusted odds ratios
Table 4. The association between disc degeneration and life-time lifting exposure ( Newton × hours, Nh) among lower lumbar level#
Intervertebral disc level
(0.6-5.1) (0.5-4.4) (1.8-9.6) (1.7-9.0)
(1.4-5.0) (0.8-3.4) (2.1-9.8) (1.2-6.1)
P-values for trend *@ *@ *
$ Adjusted for age, gender, BMI and smoking (pack-yr)
* Statistically significant, p< .05
@ Statistically significant after Bonferroni correction, p< .0042 OR, odds ratios; AOR, adjusted odds ratios
Supplementary Table 1. Percentage agreement for intra-reader reliability of all MRI variables
Degeneration sign
Intervertebral disc level
L1- L2 L2- L3 L3- L4 L4- L5 L5-S1 L1-S1
Dehydration 0.867 0.883 0.883 0.933 0.900 0.893
Annulus tear 1.000 0.950 0.983 0.883 0.883 0.940
Disc height narrowing 0.967 0.967 0.933 0.950 0.917 0.947
Bulging 0.933 0.883 0.883 0.833 0.883 0.833
Protruding 0.983 0.950 0.967 0.933 0.917 0.950
Extruding 1.000 1.000 1.000 1.000 1.000 1.000
Sequestration 1.000 1.000 1.000 1.000 1.000 1.000
Degenerative spondylolisthesis 1.000 1.000 0.967 0.967 0.983 0.983
Spondylolytic spondylolisthesis 1.000 1.000 1.000 1.000 1.000 1.000
Foramina narrowing 1.000 0.975 0.959 0.842 0.925 0.940
Nerve root compression 1.000 1.000 0.975 0.967 0.933 0.975
Supplementary Table 2. Kappa value for intra-reader reliability of all MRI variables
Degeneration sign
Intervertebral disc level
L1- L2 L2- L3 L3- L4 L4- L5 L5-S1 L1-S1
Dehydration 0.610 0.759 0.741 0.804 0.721 0.727
Annulus tear 1.000 0.545 0.900 0.685 0.708 0.768
Disc height narrowing 0.483 - 0.017 0.000 0.700 0.621 0.357
Bulging 0.838 0.860 0.828 0.765 0.861 0.830
Protruding 0.900 0.545 0.856 0.867 0.833 0.800
Extruding 1.000 1.000 1.000 1.000 1.000 1.000
Sequestration 1.000 1.000 1.000 1.000 1.000 1.000
Degenerative spondylolisthesis 1.000 1.000 0.483 0.870 0.659 0.802
Spondylolytic spondylolisthesis 1.000 1.000 1.000 1.000 1.000 1.000
Foramina narrowing 1.000 1.000 0.688 0.513 0.740 0.788
Nerve root compression 1.000 1.000 0.573 0.650 0.565 0.758
Part II. Threshold Values of Lumbar Load in Lifting for Calculating Lifetime Cumulative Load to Predict Disc Protrusion
Table 1. Demographic characteristics of the study participants
Variables Male, N= 252
BMI, body mass index; SD, standard deviation
*Yes means ever having regular exercise for 30 minutes or longer each session, at least one session per week, minimum duration of 3 months, from age of 12 years to the present time.
1~<20 43 (17.1) 13 (4.3) 52 (9.5)
> 20 70 (27.9) 0 (0.1) 70 (12.8)
Exercise* (Yes) 171 (67.9) 185 (62.5) 356 (65.0)
Table 2. Performance of predictive abilities for L4-S1 disc protrusion as measured by area-under-curve (AUC) of receiver-operator characteristic (ROC) curve, R-square, Akaike information criterion (AIC), and Bayesian information criterion (BIC) of cumulating lifetime lifting load using various threshold values in male participants
The association between lifetime lifting load for L4-S1 disc protrusion were analyzed by using logistic regression, adjusting for age, body mass index (BMI), and smoking
Table 3. Performance of predictive abilities for L4-S1 disc protrusion as measured by area-under-curve (AUC) of receiver-operator characteristic (ROC) curve, R-square, Akaike information criterion (AIC), and Bayesian information criterion (BIC) of cumulating lifetime lifting load using various threshold values in female participants
The association between lifetime lifting load for L4-S1 disc protrusion were analyzed by using logistic regression, adjusting for age, body mass index (BMI), and smoking
Table 4. The association (as shown by adjusted odds ratio, aOR) between L4-S1 disc protrusion and lifetime cumulative lifting load when only lift loads above different threshold values were calculated in male participants
disc protrusion at lower disc level (L4-S1)
Lifetime cumulative lifting load (Newton-hr) n AOR
Only lift load above 4000 N was included
Low 0 137 1
Intermediate 0~< 4.0×106 58 1.6 (0.8-3.1)
High >4 ×106 57 1.9 (1.0-3.8)
Only lift load above 3400 N was included
Low 0 96 1
Intermediate 0~< 4.0×106 73 1.6 (0.8-3.3)
High >4 ×106 83 2.0* (1.0-3.9)
Only lift load above 3000 N was included
Adjusted for age, BMI, smoking
Statistically significant: *, P<.05; **, P<.01; ***, P<.001.
Table 5. The association (as shown by adjusted odds ratio, aOR) between L4-S1 disc protrusion and lifetime cumulative lifting load when only lift loads above different threshold values were calculated in female participants
disc protrusion at lower disc level (L45-S1)
Lifetime cumulative lifting load (Newton-hr) n AOR
Only lift load above 4000 N was included
Low 0 254 1
Intermediate 0~< 2.0×106 24 0.7 (0.2-1.9)
High > 2.0 ×106 23 2.6* (1.0-6.2)
Only lift load above 3400 N was included
Low 0 206 1
Intermediate 0~< 2.5×106 47 1.6 (0.7-3.4)
High > 2.5 ×106 48 1.9 (0.9-3.9)
Only lift load above 2800 N was included
Adjusted for age, BMI, smoking
Statistically significant: *, P<.05; **, P<.01; ***, P<.001.
Part III. Prediction of Lumbar Disc Bulging or Protrusion Based on Anthropometric Factors and Disc Morphology
Table 1. Demographic characteristics of the study participants (n=452)
Variables N (%)
Age, mean + SD (years) 49.3 + 10.5
< 40 88 (19.5)
40~<50 10 (24.3)
50~<60 188 (41.6)
> 60 66 (14.6)
Gender
Male/Female 210 (46.5) /242(53.5)
Body height, mean + SD (cm) 162.8 + 7.9
Body weight, mean + SD (kg) 65.5 + 11.6
BMI, mean + SD (kg/m2) 24.6 + 3.6
< 24 191 (42.3)
24~<27 159 (35.2)
> 27 102 (22.6)
BMI, body mass index; SD, standard deviation
Table 2. The disc morphology factors of the L3-L4, L4-L5, and L5-S1 levels Disc level Disc height,
mean + SD (mm)
Table 3. Intrareader reliability of disc bulging/protrusion in MRI by percentage agreement
Disc level Interreader reliability Disc bulging or
protrusion
L3-L4 0.883
L4-L5 0.833
L5-S1 0.883
Table 4. Intrareader and interreader reliability of disc height and disc depth measurement by interclass correlation coefficients (ICC)
Disc level Interreader reliability Intrareader reliability Disc height
Table 5. The association between anthropometric factors and disc bulging or protrusion, and anthropometric factors with disc morphology and disc bulging or protrusion at the L3-L4, L4-L5, and L5-S1 levels by logistic regression
L3-L4
List of Figures
Part I. Dose-Response Relationship between Lumbar Disc Degeneration and Life Time Cumulative Lifting Load
Questionnaire
Psychiatric condition n=16 Spinal tumor n=13
Inflammatory spondylopathy n=4
Major back trauma n=27 Compression fracture n=18
Subjects
Figure1. Flow diagram of the participants selection process in the study
Part II. Threshold Values of Lumbar Load in Lifting for Calculating Lifetime Cumulative Load to Predict Disc Protrusion
Figure 1 (a). The AUC statistic distrubution of L4-S1 disc protrusion with proposed threshold values in male participants
Figure 1 (b). The R Square values of L4-S1 disc protrusion with proposed threshold values in male participants
Figure 1 (c). The AIC values of L4-S1 disc protrusion with proposed threshold values in male participants
Figure 1 (d). The BIC values of L4-S1 disc protrusion with proposed threshold values in male participants
Figure 2 (a). The AUC statistic distrubution of L4-S1 disc protrusion with proposed threshold values in female participants
Figure 2 (b). The R Square values of L4-S1 disc protrusion with proposed threshold values in female participants
Figure 2 (c). The AIC values of L4-S1 disc protrusion with proposed threshold values in female participants
Figure 2 (d). The BIC values of L4-S1 disc protrusion with proposed threshold values in female participants
Model_0 Model_3000 Model_3400
0 20 40 60 80 100
100
80
60
40
20
0
100-Specificity
Sensitivity
Figure 3. Receiver-operating characteristic curves for the prediction of L4-S1 disc protrusion in male participants by models of different threshold of lifting load.
Model 0: AUC (95% CI) = 0.65 (0.61 - 0.71). P = 0.0001 Model 3000: AUC (95% CI) = 0.69 (0.63 -0.74). P = 0.0001 Model 3400: AUC (95% CI) = 0.67 (0.61 - 0.73). P = 0.0001 Pairwise comparison of ROC curves
p-value for comparison of AUCs for Model 0 and Model 3000 = 0.149 p-value for comparison of AUCs for Model 3000 and Model 3400 = 0.155 p-value for comparison of AUCs for Model 3400 and Model 0 = 0.912
Model_0 Model_2800 Model_3400
0 20 40 60 80 100
100
80
60
40
20
0
100-Specificity
Sensitivity
Figure 4. Receiver-operating characteristic curves for the prediction of L4-S1disc protrusion in female participants by models of different threshold of lifting load.
Model 0: AUC (95% CI) = 0.60 (0.54 - 0.65). P = 0.0154 Model 2800: AUC (95% CI) = 0.62 (0.56 - 0.67). P = 0.0031 Model 3400: AUC (95% CI) = 0.59 (0.54 - 0.65). P = 0.0159 Pairwise comparison of ROC curves
p-value for comparison of AUCs for Model 0 and Model 2800 = 0.465 p-value for comparison of AUCs for Model 2800 and Model 3400 = 0.502 p-value for comparison of AUCs for Model 3400 and Model 0 = 0.988
Part III.Prediction of Lumbar Disc Bulging or Protrusion Based on Anthropometric Factors and Disc Morphology
Figure 1. Receiver-operating characteristic curves for the prediction of L3-L4 disc bulging/protrusion by model 1 and model 2
Model 1: AUC (95% CI) = 0.77 (0.73–0.81). P = 0.0001*
Model 2: AUC (95% CI) = 0.81 (0.77–0.85). P = 0.0001*
p-value for comparison of AUCs < 0.05
Figure 2. Receiver-operating characteristic curves for the prediction of L4-L5 disc bulging/protrusion by model 1 and model 2
Model 1: AUC (95% CI) = 0.74 (0.70 - 0.78). P = 0.0001*
Model 2: AUC (95% CI) = 0.77 (0.73 - 0.81). P= 0.0001*
p-value for comparison of AUCs < 0.05
Figure 3. Receiver-operating characteristic curves for the prediction of L5-S1 disc bulging/protrusion by model 1 and model 2.
Model 1: AUC (95% CI) = 0.65 (0.61–0.70). P = 0.0001*
Model 2: AUC (95% CI) = 0.67 (0.63 – 0.72). P = 0.0001*
p-value for comparison of AUCs > 0.05
Appendix
流水編號：
臺灣地區下背痛調查問卷
您好！
這份問卷是評估造成下背痛的各項因子。您所提供的寶貴資料，將有助於了 解下背痛之病因，與尋求解決與預防之方法。您是我們抽樣的對象，誠心請您能 配合填寫此問卷，所有資料將僅用於統計分析，內容絕對保密，不另做他用，請 您放心填寫，謝謝您的配合。
敬祝您 身體健康、工作愉快！
臺大醫院環境及職業醫學部郭育良教授 (2008/9/1)
第一部分: 基本資料與健康狀況
姓名 : ______________ 性別 :□男 □女
聯絡方式(白天) : 電話 : _____________ 行動電話 : ________________
出生年月日:民國 ＿U＿ U年 ＿＿月 日
年齡 : ____ 歲 身高: 公分 體重: 公斤
教育程度： □小學或以下 □國中 □高中職 □專科 □大學 □研究所 婚姻狀況： □未婚 □已婚 □離婚或分居 □鰥寡
育有子女數：□無 □一人 □二人 □三人 □四人或以上
若您是女性，您是否曾經懷孕? □沒有 □有，懷孕 次，出生 人
1. 請您回想一下，從上了國中(12歲)之後，有沒有什麼運動是您每個禮拜都會
4.我現在想請教您有關喝茶習慣的問題(U連續 6 個月以上，每個月至少喝兩次才
第二部分: 下背痛資料
□長時間坐
□向前彎腰
□向後彎腰
□持續站立 /轉身/走路
□其他，請列明：
9 背痛時，臥床休息能否減輕疼
痛？
□可以減輕痛楚
□疼痛無改變
□不能，痛楚反而加劇
10 那種方法能減輕疼痛？(可複選) □止痛藥
□熱敷
□運動
□休息
□沒有方法
□其他，請列明：
11 請在下方橫線上用 ‘X’ 顯示你現在這次下背疼痛痛楚的程度：
完全不痛 0---1---2---3---4---5---6---7---8---9---10痛到無法忍受
12 請依據附圖勾選您不舒服(酸、痛、麻)的部位
(如無此徵狀，不用作答此題)
13 請問您現在有沒有下肢無力的 情形？
(如無此徵狀，不用作答此題)
□沒有
□左邊下肢無力
□右邊下肢無力
□兩邊下肢無力
14 您現在走路時有沒有困難？
(如無此徵狀，不用作答此題)
□沒有
□有，因為痛楚，難以開始步行
□有，因為雙腳僵硬緊張，難以 起步
□有，因持續步行後下肢疼痛(或 無力或麻痺
□有，因為其他原因
(請列明： )
15 您現在能否持續走路或站立？ □能， ( ) 分鐘
□不能，剛開始時背或腳已很疼 痛
□不能，剛開始時沒問題，
之後背痛更嚴重
□不能，剛開始時沒問題，
之後臀/腳痛更嚴重
22.下背痛生活障礙問卷(以最近半年之情形作答)
第三部分：交通工具使用調查
1. 請問您平時必須乘坐/駕駛的車種及平均時間為?
車種代號 平均時間(小時/天) 駕駛年數
工作中 (1)
(2) (3) 工作以外(包括通勤) (1) (2) (3)
(1)機車 (2)汽車 (3)公車/客運 (4)捷運 (5)火車 (6)小貨車 (7)貨運卡車 (8)拖車 (9)垃圾車 (10)堆高機 (11)起重機 (12) 鐵輪壓路機 (13)混凝土 破壞機(14)曳引貨櫃車 (15)砂石車 (16)油罐車 (17)腳踏車
(18)其他---請自行填入到車種代號空格中
第四部分：職業與工作內容描述(僅列超過六個月的工作)
(次/天)