Table 3.

Results of the evaluation of angiogenesis

Average number of CD31+ microvessels by position in femoral head (SD)
	Subchondral bone
	1	2	3	4	Total	P value
CD	2.0 (3.2)	5.5 (4.0)	2.0 (2.5)	3.8 (3.1)	3.3 (3.3)	< 0.01
HG	0.4 (0.7)	0.3 (0.6)	1.6 (3.2)	0.5 (1.0)	0.7 (1.7)	< 0.0001
MSC	2.3 (5.0)	4.3 (7.5)	2.2 (3.7)	1.3 (2.4)	2.5 (4.8)	< 0.01
PGK-PDGF-BB-MSC	10.5 (10.6)	6.3 (4.7)	9.4 (6.6)	6.3 (5.3)	8.1 (7.0)	1.0

	Surrounding tunnel
	5	6	7	Total	P value
CD	1.6 (2.3)	5.2 (4.3)	7.1 (4.4)	4.6 (4.2)	< 0.01
HG	0.6 (1.2)	1.7 (2.9)	3.6 (5.4)	2.1 (3.6)	< 0.0001
MSC	0.3 (0.4)	1.7 (1.7)	1.9 (2.4)	1.3 (1.8)	< 0.0001
PGK-PDGF-BB-MSC	8.4 (3.6)	11.0 (6.2)	11.3 (5.4)	10.3 (5.0)	1.0

	Inside CD
	8	9	10	Total	P value
CD	10.0 (8.5)	10.3 (6.6)	8.5 (8.2)	9.6 (7.4)	< 0.01
HG	6.0 (5.2)	5.7 (5.4)	5.1 (5.3)	5.6 (5.0)	< 0.001
MSC	4.6 (4.6)	7.9 (8.9)	10.2 (13.5)	7.6 (9.4)	< 0.01
PGK-PDGF-BB-MSC	16.5 (6.8)	20.4 (8.5)	25.9 (11.8)	20.9 (9.6)	1.0

The average number of CD31+  microvessels for each position in the femoral head as described in Fig. 1 was calculated for each treatment group. The average number of CD31+ microvessels for each region in the femoral head was calculated for each treatment group. A mixed effects model, where treatment group and femoral head position served as fixed effects, was used to perform the statistical analysis. The P values shown correspond to comparisons with the PGK-PDGF-BB-MSC treatment group. Comparisons between all other treatment groups did not reach statistical significance. SD standard deviation, CD core decompression, HG hydrogel, MSC mesenchymal stromal cell, PGK-PDGF-BB-MSC genetically modified phosphoglycerate kinase promoter platelet-derived growth factor-BB over-expressing MSC