Post-traumatic proximal radioulnar synostosis: results of surgical treatment and review of the literature Giuseppe Giannicola, MD, PhD*, Paolo Spinello, MD, Ciro Villani, MD, Gianluca Cinotti, MD, PhD Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, ‘‘Sapienza’’ University of Rome–Policlinico Umberto I, Rome, Italy Background: Post-traumatic proximal radioulnar synostosis is a very rare and disabling condition whose surgical treatment has traditionally been viewed with pessimism. The results of the few case series in the literature are conflicting. Our aims were (1) to describe the clinical results of a case series treated sur- gically by a single elbow surgeon and (2) to review the literature. Methods: Twelve patients were evaluated. Preoperative radiographs and computed tomography scans were performed. According to the Viola and Hastings classification, there was 1 case of type IC synos- tosis; 3, type IIA; 2, type IIIA; and 8, type IIIB. Two patients had a double synostosis. The synostosis was excised in 10 cases; in addition, radial head excision, radial head arthroplasty, and proximal radial diaphyseal resection were performed in 1, 3, and 2 cases, respectively. The Mayo Elbow Performance Score, modified American Shoulder and Elbow Surgeons score, and QuickDASH (short version of Dis- abilities of the Arm, Shoulder and Hand questionnaire) score were used for the preoperative and post- operative evaluation. The nonparametric Wilcoxon signed rank test was used for the statistical analysis. Results: The mean follow-up period was 20.5 months. The final mean extension-flexion and pronation-supination arcs were 116  and 123  , respectively. Significant improvements were found in the Mayo Elbow Performance Score (P ¼ .005), modified American Shoulder and Elbow Surgeons score (P ¼ .012), and QuickDASH score (P ¼ .002), with mean values of 24, 28, and 17, respectively. One synostosis recurrence and one late disassembly of the radial head arthroplasty were observed. Conclusions: Post-traumatic proximal radioulnar synostosis surgery is effective, but careful preopera- tive planning based on the pathoanatomic characteristics of each type of synostosis and associated le- sions is mandatory. Synostosis excision is performed in most cases, whereas additional surgical procedures should be considered in selected cases. Level of evidence: Level IV; Case Series; Treatment Study Ó 2019 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved. Keywords: Elbow synostosis; radioulnar synostosis; elbow stiffness; synostosis treatment; post-traumatic synostosis; elbow surgery Institutional review board approval was not required for this treatment study. *Reprint requests: Giuseppe Giannicola, MD, PhD, Via Emilio Repossi 15, 00158, Rome, Italy. E-mail address: giannicola.giuseppe@gmail.com (G. Giannicola). J Shoulder Elbow Surg (2019) -, 1–11 www.elsevier.com/locate/ymse 1058-2746/$ - see front matter Ó 2019 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved. https://doi.org/10.1016/j.jse.2019.07.026