The Clinical Efficacy Of The Treatment Of Developmental Dysplasia Of The Hip With The Modified Salter Pelvic Osteotomy

Objective : To introduce a modified Salter pelvic osteotomy and compare the clinical efficacy of this modified Salter pelvic osteotomy and the classical Salter pelvic osteotomy.Methods: It was collected and analyzed retrospectively that the clinical data of 54 patients(54 hips)with developmental dysplasia of the hip treated with(traditional or modified)Salter pelvic osteotomy in the first orthopedic ward of our hospital from January 2012 to December 2017.And the data include all the imaging data before and after surgery and the physical examination at the final follow-up.All patients were simulated(traditional or modified)Salter pelvic osteotomy before surgery by Mimics 20.0 software,and the acetabular index after the simulated operation was measured.The children were divided into the traditional group and the improved group according to the distance of the distal iliac bone movement during the operation,and the improved group was divided into two groups according to the distance of the distal iliac bone movement(2.5mm and 5mm).We compare the clinical efficacy of modified Salter pelvic osteotomy with traditional Salter pelvic osteotomy by acetabular index(AI),Severin classification and modified McKay clinical evaluation criteria.Results: All the cases were followed up more than 6 months.The period ranged from 6 to 79 months,with an average of 26.27 ±17.81 months.During the follow-up period,avascular osteonecrosis of the femoral head occurred in 3 hips,which were all in the traditional group.Clinically,the excellent and good rates of the traditional group,the modified group(2.5mm)and the modified group(5mm)were 76.19% and 80.95%,91.67% at final follow-up.Radiographically,80.9% of hips in the traditional group had the excellent and good results,and the excellent and good rates of the modified group(2.5mm)and the modified group(5mm)both were 100%.The preoperative acetabular index of the traditional group was 42.26 ±4.11°,which decreased to 27.90±5.76° immediately after the surgery(p<0.05);the preoperative AI of the modified group(2.5mm)was 42.74±4.38°,which progressed to 26.78±6.86° immediately after the surgery(p<0.05).And the preoperative AI of the modified group(5mm)was 45.72±4.66°,which decreased to 22.60±7.47° immediately after the surgery(p<0.05).There was a significant difference between the simulated postoperative AI and the postoperative AI immediately after the surgery in traditional group(p <0.05),but there was not significant difference in modified groups(p >0.05).In terms of simulated corrective effect,there was no significant difference between the traditional group and the improved group(2.5mm)(p >0.05),but there was significant difference between the modified group(5mm)and the traditional group and the modified group(2.5mm)(p <0.05).In terms of corrective effect,the mean corrective effects of traditional group,modified group(2.5mm)and modified group(5mm)were 14.35 ±4.70°,15.96 ±5.15°,22.65 ±7.20 ° respectively.And there was no significant difference between the traditional group and the improved group(2.5mm)(p >0.05),but there was significant difference between the modified group(5mm)and the traditional group and the modified group(2.5mm)(p <0.05).Conclusion: Modified Salter pelvic osteotomy has good short-term clinical effect and simple operation for children with developmental acetabular dysplasia more than 18 months old.compared with classical Salter pelvic osteotomy,the incidence of avascular necrosis of the femoral head is reduced,and the excellent and good rate of short-term final results is higher,which is worth further studying and popularizing.