Table 2. Failure rate in 24 operated hips.

Stage	Failure n (%)
I + II ( n  = 10 hips)	2 (20)
III + IV ( n  = 14 hips)	10 (71.4) a
I ( n  = 2 hips)	0 (0)
II ( n  = 8 hips)	2(25)
III ( n  = 10 hips)	6 (60) b
IV ( n  = 4 hips)	4 (100)

Note: Failure has been defined as if arthroplasty was performed after core decompression, or the patient was scheduled for hip replacement.

^a p < 0.05 stage I + II versus stage III + IV.

^b p  > 0.05 stage III versus stage I + II.