Table 1.

Comparison between the two groups

Parameter	BMP-positive	BMP-negative	p Value
Total number of patients	17	23
Number of patients who developed HO	10 (59%)	1 (4%)	< 0.001
Number of patients who underwent excision of HO	4 (24%)	0 (0%)	0.026
Average subchondral bone settlement during healing (mm)	1	2.3	0.78

BMP = bone morphogenetic protein; HO = heterotopic ossification.