Secondary Suture Fusion after Primary Correction of Nonsyndromic Craniosynostosis: Recognition of the Problem and Identification of Risk Factors

BACKGROUND: Secondary fusion of initially patent cranial sutures after primary correction of nonsyndromic craniosynostosis is rarely reported. This study's aim is to report the incidence and analyze whether there are variables that may predispose to such fusion. METHODS: A single-institution, retrospective, case-control study was conducted of all nonsyndromic patients who underwent operative treatment for craniosynostosis from April of 2008 to May of 2017. Patients with less than 1 year of follow-up and/or without a 1-year postoperative computed tomographic scan were excluded. Preoperative, intraoperative, and postoperative variables were analyzed using univariate and multivariate analyses. RESULTS: Sixty-six patients were included in the study, with a mean 2.57-year postoperative follow-up. Six patients (8.8 percent) were found to have secondary craniosynostosis, all of whom had fusion of sutures that were initially patent and refusion of the primary pathologic suture(s). Fifty percent of secondary fusions presented as pansynostosis. On univariate analysis, suturectomy with barrel staving (p < 0.01) was significantly associated with secondary suture fusion. On multivariate analysis, bilambdoid suture involvement (p = 0.03) and suturectomy with barrel staving (p = 0.01) were significantly associated with secondary suture fusion. CONCLUSIONS: Secondary cranial suture fusion may be a relatively common complication after primary craniosynostosis correction. Suturectomy with barrel staving was independently associated with secondary craniosynostosis. Wide surgical separation of the dura from the cranium and osteotomies across patent sutures may predispose to secondary craniosynostosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.