. Author manuscript; available in PMC: 2012 May 10.

Published in final edited form as: Mater Sci Eng C Mater Biol Appl. 2011 May 10;31(4):781–788. doi: 10.1016/j.msec.2010.11.029

Table 1.

The combined model including fluid flow and complex polymer behavior (stretched exponential) separates cartilage stress-relaxation into short-and long-term processes. Short-term processes were described by the polymer (stretched exponential) model, and long-term processes were described by the fluid flow (KLM) model. The average time constant for the KLM portion of the fit (1094.9 seconds: calculated from Ha, permeability and diameter of 5 mm) was 148 times larger than the average stretched exponential time constant (7.6 sec).

	S_∞ (N)	ν	E_s (kPa)	H_a (kPa)	Permeability (m²/Pa-sec)	τ_KLM (sec)	Avg. Error (N)	S_KWW (N)	β	τ_KWW (sec)	r²

Mean	-2.91	0.20	740.1	854.5	8.50E-15	1094.9	0.03	-24.85	0.64	7.6	0.9998
Stdev	1.82	0.12	464.1	472.2	3.56E-15	323.5	0.02	17.59	0.04	1.0	0.0002