Table 2.

Patient numbers, frequencies and scores of five radiographic features, that is, narrowing of the intervertebral space, soft tissue calcifications, vacuum phenomena, osteophytes and/or hyperostosis and spinal fusion in the cervical, thoracic and lumbosacral regions of spine in 138 patients with alkaptonuria (N=138) at the baseline. Sum of scores=scoring×number of patients. Total score=sum of scores (cervical)+sum of scores (thoracic)+sum of scores (lumbosacral)

	Cervical		Thoracic		Lumbosacral
Scoring	Number of patients (%)	Sum of scores	Number of patients (%)	Sum of scores	Number of patients (%)	Sum of scores	Cumulative score
	Narrowing of the intervertebral space
0	52 (37.7)	0	40 (29.0)	0	25 (18.1)	0	0
1	38 (27.5)	38	40 (29.0)	40	16 (11.6)	16	94
2	48 (34.8)	96	58 (42.0)	116	97 (70.3)	194	406
≥1	86 (62.3)	134	98 (71.0)	156	113 (81.9)	210	500
	Calcifications
0	104 (75.4)	0	36 (26.1)	0	32 (23.2)	0	0
1	32 (23.2)	32	42 (30.4)	42	29 (21.0)	29	103
2	2 (1.4)	4	60 (43.5)	120	77 (55.8)	154	278
≥1	34 (24.6)	36	102 (73.9)	162	106 (76.8)	183	381
	Vacuum phenomena
0	95 (68.8)	0	96 (69.6)	0	51 (37)	0	0
1	16 (11.6)	16	15 (10.9)	15	23 (16.7)	23	54
2	27 (19.6)	54	27 (19.6)	54	64 (46.4)	128	236
≥1	43 (31.2)	70	42 (30.5)	69	87 (63.0)	151	290
	Osteophytes/hyperostosis
0	60 (43.5)	0	46 (33.3)	0	35 (25.4)	0	0
1	60 (43.5)	60	42 (30.4)	42	35 (25.4)	35	137
2	18 (13.0)	36	50 (36.2)	100	68 (49.3)	136	272
≥1	78 (56.5)	96	92 (66.7)	142	103 (74.7)	171	409
	Spinal fusions
0	133 (96.4)	0	119 (86.2)	0	111 (80.4)	0	0
1	3 (2.2)	3	13 (9.4)	13	11 (8.0)	11	27
2	2 (1.4)	4	6 (4.3)	12	16 (11.6)	32	48
≥1	5 (3.6)	7	19 (13.8)	25	27 (19.6)	43	75