Identification and characterization of NF1 and non-NF1 congenital pseudarthrosis of the tibia based on germline NF1 variants: genetic and clinical analysis of 75 patients

Table 2 Statistical data of clinical features of 74 probands in four groups: NF1 vs. non-NF1, NF1⁺ vs. NF1⁻

Clinical Group	Features^a	NF1 ⁺	NF1 ⁻	NF1 CPT	non-NF1 CPT	NF1⁺ %	NF1⁻ %	NF1 CPT %	non-NF1 CPT %	Fisher’s test P value (NF1⁺ vs. NF1⁻)	Fisher’s test P value (NF1 vs. non-NF1)
Total	74	43	11	54	20
Bowing time										0.098	0.587
	<1y	32	10	42	19	82.1	90.9	84.0	95.0
	1-3y	7	0	7	1	17.9	0.0	14.0	5.0
	>3y	0	1	1	0	0.0	9.1	2.0	0.0
	NA	4	0	4	0
Crawford classification										0.004	0.001
	I	0	2	2	2	0.0	18.2	3.7	10.0
	II	11	4	15	2	25.6	36.4	27.8	10.0
	III	0	1	1	6	0.0	9.1	1.9	30.0
	IV	32	4	36	10	74.4	36.4	66.7	50.0
Fracture										0.156	0.247
	Yes	20	5	18	14	71.4	45.5	56.3	73.7
	No	8	6	14	5	28.6	54.5	43.8	26.3
	NA	15	0	22	1
Fracture time										0.161	0.265
	<1y	14	4	18	8	42.4	80.0	47.4	57.1
	1-3y	14	0	14	2	42.4	0.0	36.8	14.3
	>3y	5	1	6	4	15.2	20.0	15.8	28.6
	NA	10	6	16	6
Lateralization										0.502	0.558
	Unilateral	41	10	51	20	95.3	90.9	94.4	100.0
	Bilateral	2	1	3	0	4.7	9.1	5.6	0.0
Brace										0.129	0.008
	Yes	34	6	40	20	79.1	54.5	74.1	100.0
	No	9	5	14	0	20.9	45.5	25.9	0.0
Tibial union on last followup										0.171	0.435
	Yes	36	11	47	19	83.7	100.0	87.0	95.0
	No	7	0	7	1	16.3	0.0	13.0	5.0
APTE										0.09	0.659
	Yes	4	0	4	2	36.4	0.0	7.4	10.0
	No	7	11	50	18	63.6	100.0	92.6	90.0
Pathology
	FTH	34	5	39	15	100.0	100.0	100.0	100.0
	HD	29	5	34	14	85.3	100.0	87.2	93.3
	TWA	34	4	38	14	100.0	80.0	97.4	93.3
	MD	4	3	7	1	11.8	60.0	17.9	6.7	0.032	0.419
	CTF	8	3	11	5	23.5	60.0	28.2	33.3	0.125	0.747
	ICI	3	0	3	3	8.8	0.0	7.7	20.0	1	0.331
	MGC	5	1	6	2	14.7	20.0	15.4	13.3
	NA	9	6	15	5

^ay - year(s) old; NF1⁺ NF1 pathogenic variants identified, NF1⁻ no NF1 pathogenic variants identified. NA not available, APTE Abnormality of the proximal tibial epiphysis, FTH Fibrovascular tissue hyperplasia, HD hyaline degeneration, TWA thick-walled angiogenesis, MD mucoid denaturation, CTF chondroid tissue focally, MGC multinuclear giant cells, ICI inflammatory cell infiltration

ISSN: 1750-1172