Table 3 –

Mechanical characteristics from experimental results and FE analysis for standard and growing rod constructs (mean ± standard deviation, for experimental results; value and percent error between experimental and FE, for FE analysis). Statistical significance (p < 0.05) between the standard and growing rod constructs denoted by * and between growing rod constructs of varied lengths (76 and 376mm) denoted by **.

Configuration	Stiffness (N/mm)	Yield Load (N)	Yield Displacement (mm)	Maximum Load (N)	Maximum Displacement (mm)
Experimental, Standard
Active Length = 76mm	43 ± 0.4	457 ± 19	12 ± 0.5	1,007 ± 7	65 ± 1.2
Experimental, Growing Rod
Active Length = 76mm	49 ± 0.8*	522 ± 12*	12 ± 0.1	1,084 ± 11*	62 ± 0.9*
Active Length = 376mm	10 ± 0.3**	200 ± 2**	28 ± 0.7**	392 ± 5**	134 ± 2.4**
Finite Element, Standard
Active Length = 76mm	44.3 (‒2.0%)	484.0 (‒6.0%)	12.3 (‒3.8%)	935.9 (7.1%)	66.0 (1.4%)
Finite Element, Growing Rod
Active Length = 76mm	53.4 (‒7.9%)	503.4 (3.6%)	10.9 (9.8%)	1,068.3 (1.5%)	66.0 (‒5.9%)
Active Length = 376mm	7.6 (22.1%)	191.6 (4.0%)	32.3 (‒16.4%)	294.8 (24.8%)	136.0 (‒1.5%)