Table 2.

Postoperative conditions of two clusters of patients.

Postoperative conditions	Overall (n = 616)	Cluster 1 (n = 469)	Cluster 2 (n = 147)	p-value
Respiratory failure				0.143
Yes	3 (0.49%)	1 (0.21%)	2 (1.36%)
No	613 (99.51%)	468 (99.79%)	145 (98.64%)
Peptic ulcer postoperation				0.633
Yes	6 (0.97%)	4 (0.85%)	2 (1.36%)
No	610 (99.03%)	465 (99.15%)	145 (98.64%)
Dysphagia				0.674
Yes	7 (1.14%)	5 (1.06%)	2 (1.36%)
No	609 (98.86%)	464 (98.94%)	145 (98.64%)
Pneumonia				0.010
Yes	12 (1.95%)	5 (1.06%)	7 (4.76%)
No	604 (98.05%)	464 (98.94%)	140 (95.24%)
Hoarseness				1.000
Yes	4 (0.65%)	3 (0.64%)	1 (0.68%)
No	612 (99.35%)	466 (99.36%)	146 (99.32%)
Mental disorder				0.559
Yes	3 (0.49%)	2 (0.43%)	1 (0.68%)
No	613 (99.51%)	467 (99.57%)	146 (99.32%)
Axial pain				0.559
Yes	3 (0.49%)	2 (0.43%)	1 (0.68%)
No	613 (99.51%)	467 (99.57%)	146 (99.32%)
Leakage of cerebrospinal				0.149
Yes	6 (0.97%)	3 (0.64%)	3 (2.04%)
No	610 (99.03%)	466 (99.36%)	143 (97.96%)
Esophagostoma				0.421
Yes	2 (0.32%)	1 (0.21%)	1 (0.68%)
No	614 (99.68%)	468 (99.79%)	146 (99.32%)
Wound hematomas				1.000
Yes	6 (0.97%)	5 (1.06%)	1 (0.68%)
No	610 (99.03%)	464 (98.94%)	146 (99.32%)
Sense of girdle				0.239
Yes	1 (0.16%)	0 (0%)	1 (0.68%)
No	615 (99.84%)	469 (100%)	146 (99.32%)
Wound infection				0.559
Yes	3 (0.49%)	2 (0.43%)	1 (0.68%)
No	613 (99.51%)	467 (99.57%)	146 (99.32%)
JOA improvement rate >25%				0.214
Yes	601 (97.56%)	460 (98.08%)	141 (95.92%)
No	15 (2.44%)	9 (1.92%)	6 (4.08%)
Blood transfusion				0.280
Yes	31 (5.03%)	21 (4.48%)	10 (6.80%)
No	585 (94.97%)	448 (95.52%)	137 (93.20%)