Intra-articular injection of collagenase in the knee of rats as an alternative model to study nociception associated with osteoarthritis

Table 1 Correlation analysis

Pearson correlation coefficient
	One week				Six weeks
	250 U		500 U		250 U		500 U
vs	KB	CW	KB	CW	KB	CW	KB	CW
Knee diameter	0.768	−0.137	0.791	0.136	−0.017	0.564	−0.152	0.350
	**	-	**	-	-	-	-	-
CMLW 0%	0.474	−0.389	0.929	−0.732	0.764	−0.436	0.808	−0.710
	-	-	*******	*	*	-	**	*
CMLW 50%	-	-	0.506	−0.495	-	-	0.569	−0.609
	-	-	-	-	-	-	-	-
CMLW 100%	-	-	-	-	-	-	0.456	−0.221
	-	-	-	-	-	-	-	-
TCDW	0.674	−0.407	0.801	−0.358	0.871	−0.341	0.853	−0.696
	*	-	**	-	**	-	**	*
SCDW	0.260	−0.193	0.414	−0.005	0.516	0.109	0.880	−0.630
	-	-	-	-	-	-	**	-
ZDR Z1	0.433	−0.536	0.331	0.034	0.452	0.068	0.487	−0.526
	-	-	-	-	-	-	-	-
ZDR Z2	0.891	−0.311	0.695	−0.328	0.747	−0.099	0.880	−0.662
	*******	-	*	-	*	-	**	-
ZDR Z3	0.8032	0.147	0.598	−0.143	0.693	0.030	0.795	−0.453
	**	-	-	-	*	-	*	-
CDS Z1	0.259	0.010	0.340	0.019	0.604	0.011	0.8182	−0.576
	-	-	-	-	-	-	**	-
CDS Z2	0.425	−0.079	0.543	−0.442	0.704	−0.425	0.863	−0.711
	-	-	-	-	*	-	**	*
CDS Z3	0.434	−0.255	0.551	−0.344	0.565	−0.476	0.659	−0.491
	-	-	-	-	-	-	-	-
OS	-	-	-	-	0.179	−0.446	0.390	−0.606
	-	-	-	-	-	-	-	-
SMIS	0.341	0.004	0.611	−0.153	0.582	−0.204	0.860	−0.433
	-	-	*	-	-	-	**	-
MJCR	0.621	0.114	0.279	0.0609	−0.190	−0.076	0.450	−0.546
	-	-	-	-	-	-	-	-
GPT	0.431	−0.106	0.592	−0.124	−0.007	0.142	0.745	−0.354
	-	-	-	-	-	-	*	-

*P <0.05, **P <0.01, ***P <0.01.
Pearson’s correlation analysis between Knee-Bend score or %TIPPI and knee diameter or the histopathology score parameters at one and six weeks for 250 U and 500 U collagenase-injected animals. CDS, Cartilage degeneration score; CMLW, Cartilage matrix loss width; GPT, Growth plate thickness; MJCR, Medial joint capsule repair; OS, Osteophytes score; SCDW, Significant cartilage degeneration width; SMIS, Synovial membrane inflammation score; TCDW, Total cartilage degeneration width; ZDR, Zonal depth ratio.

ISSN: 1478-6362