Are the outcomes of single-stage open reduction and Dega osteotomy the same when treating DDH in patients younger than 8 years old? A prospective cohort study.

Background: The primary objective was to report our early results after a one-stage procedure [open reduction (OR), Dega pelvic osteotomy (DPO), and femoral osteotomy (FO) when needed] for surgical management of a cohort of patients with developmental dysplasia of the hip (DDH). The secondary objective was to compare the functional, radiological, and complications among patients younger and older than 30 months.

Materials and methods: This prospective cohort study included 71 hips with DDH in 61 patients with a mean age of 34.3 ± 19.5 months. All patients underwent one-stage surgical procedures, including OR + DPO and FO, if needed. Functional and radiographic assessment at the last follow-up was conducted using the modified Severin grading system and the Severin classification system, respectively, in addition to assessing the acetabular index (AI), osteotomies healing, and presence of complications. We divided patients into two groups, younger than 30 months (group I) and older than 30 months (group II).

Results: We included 35 hips in group I and 36 in group II. All hips received OR + DPO, while 25 (69.4%) hips in group II had FO. The operative time was significantly longer in group II (103.19 ± 20.74 versus 72.43 ± 11.59 min, p < 0.001). After a mean follow up of 21.3 ± 2.3 months, the functional outcomes were satisfactory in 62 (87.3%) hips (94.3% in group I and 80.6% in group II, p = 0.35). There was a significant improvement in the AI in all patients compared with preoperative values (27.2° ± 2.9 versus 37° ± 4.2, p < 0.05). Furthermore, 63 (88.7%) hips had satisfactory radiographic outcomes (94.3% in group I and 83.3% in group II, p = 0.26), and all osteotomies showed radiographic healing. The overall complications incidence was significantly lower in group I compared with group II (5.7% versus 30.6%, p < 0.05), and avascular necrosis occurred in 4 (5.6%) hips, all in group II (p = 0.06).

Conclusion: One-stage procedure entailing open reduction, Dega pelvic osteotomy, and femoral osteotomy when needed for managing DDH in patients younger than eight years old revealed acceptable clinical and radiological outcomes. However, there was a higher need for a concomitant femoral osteotomy in patients older than 2.5 years, and complications were more frequent.

Level of evidence iii: