Table 1. Measured and reconstructed muscle cross section areas, muscle moment arms and maximally available torques at the base of the tail in Alligator and three versions of the Kentrosaurus reconstruction. Torques were calculated for four different specific tension values between 20 N/cm2 and 79 N/cm2. Abbreviated muscle names: ASP = m. articulospinais, CFL = m. caudofemoralis longus, ILCAUD = m. iliocaudalis, ISCAUD = m. ischiocaudalis, LCAUD = m. longissimus caudae, SPIN = m. spinalis. Alligator sections are without scale and here scaled to approximate same vertebra height as Kentrosaurus caudal, 278 mm.
muscle
area
lever arm (m)
force @ 20 N/cm2
(N)
@ 50
@ 78
torque @ 20 N/cm2
(Nm)
@ 50 N/cm2
@ 78 N/cm2
ASP + SPIN
0.011
0.046
2200
4290
5500
8580
101.2
197.3
253
394.7
LCAUD
0.038
0.149
7600
14820
19000
29640
1132.4
2208.2
2831
4416.4
CFL
0.054
0.122
10800
21060
27000
42120
1317.6
2569.3
3294
5138.6
IL- + ISCAUD
0.0495
0.193
9900
19305
24750
38610
1910.7
3725.9
4776.8
7451.7
sum
0.1525
4461.9
8700.7
11155
17401.4
Kentrosaurus
'croc'
ASP + SPIN
0.0165
0.065
3300
6435
8250
12870
214.5
418.3
536.25
836.6
LCAUD
0.0305
0.153
6100
11895
15250
23790
933.3
1820.0
2333.3
3639.9
CFL
0.0445
0.114
8900
17355
22250
34710
1014.6
1978.5
2536.5
3957.0
IL- + ISCAUD
0.035
0.169
7000
13650
17500
27300
1183
2306.9
2957.5
4613.7
sum
0.1265
3345.4
6523.5
8363.5
13047.0
Kentrosaurus
'medium'
ASP + SPIN
0.0125
0.058
2500
4875
6250
9750
145
282.8
362.5
565.5
LCAUD
0.021
0.119
4200
8190
10500
16380
499.8
974.6
1249.5
1949.2
CFL
0.015
0.069
3000
5850
7500
11700
207
403.7
517.5
807.3
IL- + ISCAUD
0.013
0.1
2600
5070
6500
10140
260
507
650
1014
sum
0.0615
1111.8
2168.0
2779.5
4336.0
Kentrosaurus
'slim'
ASP + SPIN
0.0105
0.054
2100
4095
5250
8190
113.4
221.1
283.5
442.3
LCAUD
0.011
0.1
2200
4290
5500
8580
220
429
550
858
CFL
0.008
0.06
1600
3120
4000
6240
96
187.2
240
374.4
IL- + ISCAUD
0.007
0.081
1400
2730
3500
5460
113.4
221.13
283.5
442.3
sum
0.0365
542.8
1058.5
1357
2117.0
(m2)
@ 39 N/cm2
N/cm2
N/cm2
@ 39 N/cm2
Alligator