Posterior Vault Distraction Osteogenesis: A Systematic Review and Single-Arm Metanalysis

Introduction: The purpose of this study is to describe the technique and outcomes of posterior vault distraction osteogenesis (PVDO) in patients with syndromic and nonsyndromic craniosynostosis. Methods: Studies from MEDLINE, Scopus, and Cochrane Central Register of Controlled Trials were systematically searched for patients with posterior cranial vault distraction osteogenesis. Inclusion criteria encompassed all studies with 3 or more patients per cohort who underwent posterior cranial vault distraction osteogenesis and had a follow-up of at least 1 month. Patients with both syndromic and nonsyndromic synostosis were included. The risk of bias in nonrandomized studies of intervention tool (ROBINS-I) was applied. Results: A total of 19 manuscripts with 403 patients met the criteria. All but one study included patients with syndromic craniosynostosis. In total, 5.9% of cases used one distractor, 72.5% two, 3.7% three, and 7.4% four. The distraction achieved ranged from 18.7 to 35 mm with an average of 23.54 mm. Distraction protocol was, on average, 1 mm/d. The duration of the distractors from placement to extraction was 10.1 weeks. Follow-up after surgery was 27.09 months on average. Ninety-nine (26.3%) complications in 376 patients were reported, of which 31 required unplanned surgical intervention. Single-arm metanalysis of the complications associated with PVDO revealed 13.71 events (CI: 8.9-19.8) per 50 cases with moderate heterogeneity per Cochrane Q test (χ²=47.12 P<0.01) and I² test (68%). Conclusions: PVDO is an effective technique to increase cranial vault volume. Factors such as distraction protocol selected based on the patient's needs and age at the time of surgery are crucial for successful outcomes. Furthermore, distraction protocols can be tailored to specific needs, permitting a patient-centered approach. Complications are variable both in incidence as well as severity.