39 lines (34 with data), 2.2 kB

// Definition of the mechanical and geometric properties of the lumbar spine ligaments 
AnyFolder LumbarSpineLigaments = {
   AnyFloat strainratio = 0.75;
   AnyFloat mm2m = 1000;
   AnyFloat al_slack_length = 1.2;
   AnyFloat pl_slack_length = 1.2;
   AnyFloat is_slack_length = 1.2;   
   AnyFloat ss_slack_length = 1.2;   
   AnyFloat lf_slack_length = 1.2;
   
   // mean stiffness values from Pintar et al. 1992, J Biomech
   // stiffness vector L1L2, L2L3, L3L4, L4L5, L5Sacrum given in N/mm^-1
   AnyVector  kALL = {32.9, 32.4, 20.8, 39.5, 40.5, 13.2}*mm2m;     // conversion to N/m
   AnyVector  kPLL = {10.0, 17.1, 36.6, 10.6, 25.8, 21.8}*mm2m;     // conversion to N/m
   AnyVector  kISL = {12.1, 10.0, 9.6,  18.1, 8.7,  16.3}*mm2m;       // conversion to N/m   
   AnyVector  kSSL = {15.1, 23.0, 24.8, 34.8, 18.0, 17.8}*mm2m;     // conversion to N/m
   AnyVector  kLF  = {24.2, 23.0, 25.1, 34.5, 27.2, 20.2}*mm2m/2.0; // conversion to N/m + splitting (2 lig parts)
   // NB!! assumption: 75% failure strain corresponds to nominal strain
   AnyVector  epsALL = {0.319, 0.44,  0.49,  0.328, 0.447, 0.281}*strainratio;        
   AnyVector  epsPLL = {0.162, 0.157, 0.113, 0.158, 0.127, 0.15}*strainratio;   
   AnyVector  epsISL = {0.594, 1.197, 0.515, 0.965, 0.874, 0.529}*strainratio;
   AnyVector  epsSSL = {0.75,  0.834, 0.706, 1.094, 1.063, 1.151}*strainratio;
   AnyVector  epsLF  = {0.615, 0.786, 0.288, 0.706, 1.020, 0.831}*strainratio; 

   // values from Chazal et al. 1985 (not available in Pintar et al.)
   AnyVector  kIT  = 0.5*{50.0, 50.0, 50.0, 50.0, 50.0, 50.0}*mm2m; // conversion to N/m   
   AnyVector  epsIT  = {0.16,  0.16,  0.16,  0.16,  0.16,  0.16};//*strainratio;   

   AnyFolder T12L1Lig = {#include "T12L1Ligaments.any"};
   AnyFolder L1L2Lig = {#include "L1L2Ligaments.any"};
   AnyFolder L2L3Lig = {#include "L2L3Ligaments.any"};
   AnyFolder L3L4Lig = {#include "L3L4Ligaments.any"};
   AnyFolder L4L5Lig = {#include "L4L5Ligaments.any"};
   AnyFolder L5SacrumLig = {#include "L5SacrumLigaments.any"};    

   // Sacroilliac ligaments
   AnyFolder SacrumPelvisLig = {#include "SILigaments.any"};
 };