The incidence and analysis of ipsilateral occult hernia in patients undergoing hernia repair: a single institution retrospective study of 1066 patients

Table 1 Demographic characteristics of inguinal hernia cases

Variable	Occult hernia	Non-occult hernia	Total
Patients, n	88*	978	1066
Sex, n
Male	81	893	974
Female	7	85	92
Ages, years	71.68 ± 11.31 (46–95)	66.22 ± 15.73 (13–98)
Types of hernia, n	91	1053	1144**
Indirect hernia	28	829	857
Direct hernia	47	183	230
Femoral hernia	14	40	54
Obturator hernia	1	1	2
Spiglian hernia	1	0	1
Operation methods, n	88	978	1066
Endoscopic technique	27	334	361
Open surgery	61	644	705
Operators qualification, n	88	978	1066
EHS group	67	687	754
NEHS group	21	291	312
Location of inguinal hernia, n	88*	978	1066
Left groin	32	383	415
Right groin	56	510	566
Bilateral groin	0	85	85

Values are expressed as the mean ± standard deviation of the mean
EHS expert hernia surgeons, NEHS Non-expert hernia surgeons
*Three cases among 88 patients who suffered two kinds of occult hernias on the same side. **Different hernias on both sides of the same patient were counted, so the total number of types of hernia (n = 1144) exceeds the total number of patients (n = 1066)