Table 2 Characteristics of the included case series studies
| Year/author/region | Study design | Number of patients/hips (follow-up) | Average age (years) | Gender (M/F) | Initial AVN class (hips) | AVN etiology (patients/hips) | Follow-up time (year)/rate of lost to follow-up | Validity of the studies |
|---|---|---|---|---|---|---|---|---|
| 2016/Chen/China [24] | Case series | 55/64 | 34.1 (22–45) | 53/5a |
ARCO: I (21)/II (35)/III (8) | Alcohol abuse (58)a | 2.87 (2–4)/5.17% | M |
| 2014/Elmali/Turkey [25] | Case series/retrospective | 22/26 | 36 (16–48) | 14/8 |
ARCO: II (11)/III (15) | Steroid use (13 patients)/alcohol abuse (2)/idiopathic (5)/pregnancy (2) | 3 (1.17–5.17)/NA | H |
| 2009/Chen/China [26] | Case series/retrospective | 32/33 | 37 (23–64) | 31/1 |
ARCO: IIIA (26), IIIB (7) | Steroid use (1 patients)/alcohol abuse (26)/idiopathic (5) | 5.75 (0.67–13.75)/13.15% | M |
| 2009/Babhulkar/India [27] | Case series/retrospective | 31/31 | 32 (18–52) | 26/5 |
ARCO: IIB (9)/IIIC (22) | Steroid use (12 patients)/alcohol abuse (16)/idiopathic (3) | 8/NA | M |
| 2009/Baksi/India [28] | Case series | 141/176 | 35.5 (16–62) | 91/61a |
Ficat and Arlet: I (4)/II (75)/III (97) | Steroid use (56 hips)/alcohol abuse (7)/trauma (40)/idiopathic (83)/gout (1)a |
16.5 (10–21.5)/ 7.23% | M |
| 2006/Zhao/China [29] | Case series/retrospective | 197/226 | 38 (19–65) | 126/71 |
Ficat and Arlet: II (91)/III (93)/IV (42) | Steroid use (53 patients)/alcohol abuse (14)/trauma (58)/idiopathic (51)/hyperlipidemia (9)/infection (11)/pregnancy (1) | 12.5 (6–19)/6.63% | M |
| 2004/Nagoya/Japan [30] | Case series | 29/35 | 35 (17–62) | 20/9 |
ARCO: II (28)/III (7) JIC classification: C1 (17), C2 (18) | Steroid use (14 patients)/alcohol abuse (10)/idiopathic (5) | 8.58 (3–17)/NA | H |
| 2001/Eisenschenk/Germany [31] | Case series | 82/82 | NA | 81/21 a |
ARCO: I-II (62)/III (1)/IV (19) | Steroid use (12 patients)/alcohol abuse (20)/trauma (22)/diabetes (6)/hyperlipidemia (10)/sickle cell disease (1)/unknown (11) | 5 (0.5–10)/19.61%b | VH |
| 1997/Hasegawa/Japan [33] | Case series | 26/31 | 38.3 (25–53) | 23/3 |
Inoue and Ono classification: II (28)/IIIA (3) JIC classification: IB (25)/IC (4)/II (4)/ IIIB (1) | Steroid use (6 patients)/alcohol abuse (15)/idiopathic (5) | 8 (5–11)/100% | M |
| 1997/Ishizaka/Japan [32] | Case series | 24/31 | 33 (15–66) | 16/81 |
Ficat and Arlet: II (18)/III (13) | Steroid use (17 hips)/alcohol abuse (10)/idiopathic (4) | 6 (2–11)/22.58% patient | H |
| 1996/Leung/China [35] | Case series | 18/21 | 32 (24–52) | 12/6 |
Myer’s classification: III (6)/IV (8)/V (7) | Steroid use (7 hips)/alcohol abuse (3)/trauma (3)/idiopathic (8) | NA (2–11)/NA | H |
| 1996/Wassenaar/Netherlands [34] | Case series | 9/12 | 37.5 (14–54) | 5/4 |
Ficat and Arlet: II (5)/III (7) | Steroid use (3 patients)/alcohol abuse (1)/trauma (3)/chemotherapy (1)/sickle cell disease (1) | 4.17/30.77% | VH |
| 1993/Iwata/Japan [36] | Case series | 19/23 | 39 (25–53) | 17/2 |
JIC stage: II (20), III (3) JIC classification: I-C (19)/II (2)/III-B (1) | Steroid use (3 patients)/alcohol abuse (13)/idiopathic (3) | 2.91 (1–6)/100% | H |
