A Computational Modeling Approach for Investigating Soft Tissue Balancing in Bicruciate Retaining Knee Arthroplasty

Table 2

List of the model parameters and the corresponding three levels used in the design of experiments. Parameters 1 to 20 define deviations of the coordinates of the ligament attachments (in mm) on the tibia (TX, TY) and the femur (FX, FY) with respect to their corresponding 2D coordinate system (Figures 1 and 2). Parameters 21 to 25 define the stiffness parameters (𝐾) for the six different ligaments (in 𝑁). Parameters 27 to 40 are assigned to the reference strains of the ligament bundles (𝜀). (For the ligament name abbreviations see the description of Table 1.)

Parameter no.	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20
Ligament	ACL	ACL	ACL	ACL	PCL	PCL	PCL	PCL	sMCL	sMCL	sMCL	sMCL	LCL	LCL	LCL	LCL	dMCL and PMC
Parameter; name	TX	TY	FX	FY	TX	TY	FX	FY	TX	TY	FX	FY	TX	TY	FX	FY	TX	TY	FX	FY
Level #1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1	−1
Level #2	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Level #3	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1
Parameter #	21	22	23	24	25	26	27	28	29	30	31	32	33	34	35	36	37	38	39	40
Ligament	ACL	PCL	sMCL	dMCL	LCL	PMC	ACL	ACL	ACL	PCL	PCL	PCL	sMCL	sMCL	dMCL	dMCL	LCL	LCL	PMC	PMC
Group							Anterior	Middle	Posterior	Anterior	Middle	Posterior	Anterior	Posterior	Anterior	Posterior	Anterior	Posterior	Anterior	Posterior
Parameter; name	K	K	K	K	K	K	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖	𝜀𝑖
Level #1	4750	8550	2613	950	2613	950	0.155	0.095	0.095	−0.073	−0.174	−0.174	0.175	0.175	0.025	0.025	0.045	0.045	0.025	0.025
Level #2	5000	9000	2750	1000	2750	1000	0.160	0.100	0.100	−0.068	−0.169	−0.169	0.180	0.180	0.030	0.030	0.050	0.050	0.030	0.030
Level #3	5250	9450	2888	1050	2888	1050	0.165	0.105	0.105	−0.063	−0.164	−0.164	0.185	0.185	0.035	0.035	0.055	0.055	0.035	0.035