Triple osteotomy assisted with 3D CT for developmental dysplasia of the hip in elder children / 中华骨科杂志

ABSTRACT

Objective:To predict the therapeutic effect by 3D CT simulating osteotomy and to study the outcome of Bernese triple osteotomy for developmental dysplasia of the hip (DDH) in elder children (≥ 8 years).Methods:19 involved hips in12 elder Children with DDH treated with Bernese triple osteotomy from July 2014 to June 2017 were analyzed retrospectively. There were 7 involved hips in 5 boys and 12 involved hips in 7 girls with an average age of 11.14±1.98 years (8-13.33 years) at operation. 4 children were involved in left side, 1 child in right side and 7 children in both sides. 8 hips were classified in type I and 11 hips in type II as Tonnis classification. 6 hips were acetabular dysplasia with Reimers's indexes between 0.20 and 0.33 and 13 hips were subluxation with Reimers's indexes between 0.33 and 1. All the children were detected with DDH for the first time with no basic diseases and there was no previous treatment adopted. A simulating osteotomy by 3D CT of pelvis-femurs was given to each of the children pre-operation and Bernese triple osteotomy with varus derotation osteotomy in proximal femoral was applied simultaneously. The changes of Sharp angles, center edge angles, Reimers's indexes and lengths of sacrospinous ligaments were compared and P<0.05 was considered as statistical significance in the differences. Radiological results and the improvements of limbs' functions were evaluated at the latest follow-up. Results:12 children with 19 involved hips were followed up successfully with an average period of 2 years and 11months (1 year 4 months-4 years). Sharp angles were improved from 55°±3° to 36°±3°, CEAs were improved from -8°±14° to 22°±3°, Reimers's indexes were improved from 0.50±0.17 to 0.14±0.03 and lengths of sacrospinous ligaments decreased from 48.40±10.00 mm to 41.60±10.47 mm with statistical significance in the differences (all P<0.05). Disrupted Shenton lines in 12 hips pre-operation turned to be continuous post-operation. 12 hips as excellent, 4 hips as good and 3 hips as moderate with the excellent-good rate of 84% were seen as modified Severin classification. 12 hips as excellent, 6 hips as good and 1 hip as moderate with the excellent-good rate of 95% were seen as modified McKay classification. Nonunions of ischia were seen in 2 hips and limbs lengths discrepancies <2 cm were seen in 2 children. No avascular necrosis, infection, break of screw or injury of vessel and nerve was seen in all children. Conclusion:More precise indication, more meticulous operation and more intuitive outcome could be actualized assisted with 3D CT. The short-term effect of Bernese triple osteotomy for DDH in elder children is really significant and should be popularized in clinical.