TABLE 1.

Demographics of Subjects Included in the OCD Surgery Model^a

	No. of Lesions	% of All Lesions	No OCD Surgery (n = 216), %	OCD Surgery (n = 118), %	P Valueb
Total OCD lesions	334	100.0	64.7	35.3
Ethnicity					.0864
Non-Hispanic white	129	38.6	58.9	41.1
Black	61	18.3	63.9	36.1
Hispanic	106	31.7	67.0	33.0
Asian/Pacific Islander	13	3.9	61.5	38.5
Other	25	7.5	88.0	12.0
Age group					<.0001
6-11 y	76	22.8	90.8	9.2
12-19 y	258	77.2	57.0	43.0
Sex					.5636
Male	233	69.8	65.7	34.3
Female	101	30.2	62.4	37.6
Sex and age					<.001
Female, 6-11 y	22	6.6	95.5	4.5
Female, 12-19 y	79	23.7	53.2	46.8
Male, 6-11 y	54	16.2	88.9	11.1
Male, 12-19 y	179	53.6	58.7	41.3
Primary OCD location					.0641
Knee	206	61.7	66.5	33.5
Elbow/foot/shoulder	43	12.9	48.8	51.2
Ankle	85	25.4	68.2	31.8

^aMean age of study subjects was 13.5 ± 2.8 years (median, 14 years; 25th-75th percentile, 12.0, 15.0 years; range, 6.0-19.0 years). Age demographics of subjects who underwent surgery (mean, 14.8 ± 2.01 years; median, 15 years; 25th-75th percentile, 14.0-16.0 years; range, 10.0-19.0 years) were significantly different (P < 0.0001) from subjects who did not (mean, 12.8 ± 2.91 years; median, 13 years; 25th-75th percentile, 11.0-15.0 years; range, 6.0-19.0 years). OCD, osteochondritis dissecans.

^bP values obtained from t tests for continuous variables and from Mantel-Haenzel chi-square for categorical variables.