Congenital Dislocation of the Hip in Children between the Ages of One and Three: Open Reduction and Modified Salter Innominate Osteotomy Combined with Fibular Allograft

Background: Innominate osteotomy procedures have been widely used as an integral component of combined surgery to treat developmental dysplasia of the hip in children. Autograft concern is further supported by authors who suggest the routine use of internal fixation. Problems such as graft extrusion, rotation and absorption, leading to loss of acetabular correction, were often noted in cases previously treated at our National Hospital for Pediatrics. This retrospective study reviewed the radiographic results of this treatment protocol in 106 hips developmental dislocated hips which met our inclusion criteria. The efficacy of this method to achieve and maintain a well covered and stable hip was the main objective of the study. Methods: This retrospective study reviewed the radiographs of 106 hips presenting with developmental dislocation which were treated by modified Salter’s innomiate osteotomy and using a fibular allograft as the interposition material. Dislocations of the hip were graded using the Tönnis system. Measurement of the acetabular index (AI) was the main variable. The minimum follow up period was 2 years. Possible complications such as loss of acetabular correction, hip redislocation, graft extrusion or resorption, the need for osteotomy internal fixation, delayed or non union, infection or avascular necrosis (AVN) were documented in this series. Results: Between January 2004 and December 2008, 106 surgeries were performed in 95 patients. Sixty-three (86.3%) of the patients were girls and ten (13.7%) were boys, thirteen patients (13.7%) were between twelve and eighteen months old at the time of the operation, the remaining eighty-two (86.3%) patients being between eighteen and thirty-six months old, with the mean age of 22.6 months at the time of surgery. There were eleven (11.6%) patients who had bilateral dislocation. Eighty-four (88.4%) patients were affected unilaterally. The right hip was involved in seventeen (17.9%) and the left hip in sixty-seven (70.5%) cases. Tönnis system Type 3 was in 34 hip (32.1%), and Type 4 was in 72 hip (67.9%). All patients combined open reduction and modified Salter’s innomiate osteotomy, inserting a fibular allograft as the interposition material. Acetabular index was improved, preoperation was 42.95 ̊, and latest follow-up 19.15 ̊, concentrical acetabulum 93.7%. All of the fibulat allografts were completely incorporated mean 14 weeks (range, 12 weeks 17 weeks) post-surgery. There were five (4.7%) redislocation and subluxation, three AVN (2.8%) and five (4.7%) coxa magna Without graft infections, none of the osteotomies required internal fixation for stability. Final results: Excellent 70 (66.0%), Good 29 (27.4%), Fair 2 (1.9%), Poor 5 (4.7%). Conclusion: Open reduction and modified Salter’s innomiate osteotomy allow interposition material by fibular allografting with a short operative incision, renders excellent osteotomy stability that eliminates the need for internal fixation. Surgical technique are safe and effective for Children between twelve and thirty-six months old.