Table 5.
Effect of age and type of treatment on the degree of ON
| Study | Total number of hips | Mean age at reduction (months) | Mean age at final followup (years) | Overall incidence of ON | Classification and grade of ON | Significant effect of age at reduction on degree of ON | Type of treatment | Significant effect of type of treatment on degree of ON |
|---|---|---|---|---|---|---|---|---|
| Agus et al. [1] | 67 | 11.9 | 6 | 27% | (K&M [12]) 72% Group I 28% Group IV |
No | All OR via medial approach, iliopsoas and adductor tenotomy | Unable to comment |
| Brougham et al. [3] | 210 | 14 | 13 (8–20) | 47% | (Gage and Winter [9]) 18% partial 82% total |
No | All closed reduction | Unable to comment |
| Cordier et al. [7] | 118 | 9 | 15 (10–21) | 8% | (Hirohashi [10]) 78% mild 22% partial |
No | 32 OR; 37 OR & acetabuloplasty, 34 OR & acetabuloplasty & DVO; 6 OR & acetabuloplasty & DVO & femoral shortening osteotomy; 4 OR & acetabuloplasty & femoral shortening; 5 OR & DVO |
Yes, no ON with femoral shortening osteotomy |
| Domzalski and Synder [8] | 144 | 35 | 21 (17–32) | 36% | (Bucholz and Ogden [4]) 38% Type 1 23% Type 2 27% Type 3 12% Type 4 |
Yes, significant if treatment initiated after 2 years of age | All had OR and intertrochanteric femoral osteotomy. 102 Dega osteotomies, 42 Salter osteotomies | Unable to comment |
| Isiklar et al. [11] | 44 | < 12, (21 hips) > 12, (23 hips) | 20 (13–28) | 20% | (K&M [12]) 10% Group I 80% Group II 10% Group IV |
No | All had OR via Ferguson’s medial approach | Unable to comment |
| Kalamchi and MacEwen [12] | 119 | 11 | 12 (1–33) | 14% | (K&M [12]) 40% Group I 31% Group II 16% Group III 13% Group IV |
Severe ON if reduction between birth and 6 months | 87% closed reduction13% OR | Yes, recommend preliminary traction and general anesthesia to reduce the incidence of severe ON |
| Kramer et al. [15] | 809 | 2–30 | Not given | 3% | – | No | Two-phase closed reduction–longitudinal traction, stepwise hip abduction; 6 hips required OR (4 teratologic) |
Unable to comment |
| Luhmann et al. [16] | 153 | 11 | 7 (3–16) | 6% | (Bucholz and Ogden [4]) | No | 73% closed reduction27% OR | Unable to comment |
| MacNicol and Bertol [17] | 148 | 33 | 5–25 | 31% | – | No | OR and concurrent Salter osteotomy in 125 hips | Yes, combining OR and Salter osteotomy increased incidence of ON |
| Malvitz and Weinstein [18] | 152 | 21 | 31 (16–56) | 60% | (K&M [12]) 12% Group I 42% Group II 3% Group III 29% Group IV 14% not classifiable |
Yes, increased ON after 1 year at reduction | Closed reduction | Unable to comment |
| Rampal et al. [19] | 47 | 19 | 16 (11–32) | 2.1% | (K&M [12]) 100% Group I |
No | Closed reduction with traction using Petit-Morel technique | Unable to comment |
| Sibinski and Synder [22] | 155 | 14.9 | 16 (14–22) | 34% | (Bucholz and Ogden [4]) 15% Type 1 66% Type 2 15% Type 3 4% Type 4 |
No | All closed reduction | Unable to comment |
| Thomas et al. [23] | 87 | 24 | 9 (2–17) | 37% | (Gage and Winter [9]) 78% partial 22% total |
No | All OR | Unable to comment |
| Wenger et al. [26] | 20 | 16.5 | 5 (2–12) | 10% | (Gage and Winter [9]) 100% partial |
No | All OR and femoral derotation & shortening. Included 8 teratologic and 2 with cerebral palsy. | Unable to comment |
| Zionts and MacEwen [27] | 51 | 19.7 | 12 (5–22) | 39% | (Salter et al. [21]) 85% mild 15% severe |
No | 75% closed reduction 25% OR |
Yes, recommend closed reduction |
| Current study | 133 | 18.6 | 12 (6–26) | 48% | (Simplified K&M) 34% Group A 66% Group B |
No | 58% closed reduction 42% OR |
Yes, recommend closed reduction or femoral shortening with OR |
ON = osteonecrosis; K&M = Kalamchi and MacEwen; OR = open reduction; DVO = detorsion varus osteotomy.