Effectiveness of the use of hexapod fixator in the treatment of patients with blount´s Disease: Systematic Review

Introduction: Blount's disease is a disorder of posteromedial proximal tibial physis that causes progressive varus deformity, procurvatum and internal tibial rotation. The homonymous condition, described by Blount in 1937, when left untreated, can lead to progressive discrepancies in limb length, changes in gait and premature osteoarthritis. The management of Blount's disease in adolescents and young adults is complex and associated with a high risk of morbidity. The gradual correction of this deformity with the use of the hexapod external fixator can minimize soft tissue damage and allow subsequent adjustment in the degree of correction. The Hexapod system was developed as an extension of existing fixation systems. Hexapod represents a kinematic mechanism, which generates three-dimensional movements (translations and rotations) varying the length of 6 distractors. Hexapod is a well-known robotics construction for the spatial positioning of a platform. A software calculates the adjustment needs of the 6 distractors. Studies have shown that reduction or correction maneuvers with the use of Hexapod are effective in the treatment of different types of orthopedic deformities, amongthem, Blount’s disease.This study aims to analyze the effectiveness of using the Hexapod fixator in the treatment of patients with Blount’s disease. Knowing that one of the main problems for the analysis of the demonstration of efficiency of conservative treatments in Blount's disease is the lack of standardization of orthopedic devices, this study focuses on the use of the Hexapod fixative, considering what the authors have found using it. them in the treatment. It is noteworthy that this study proposes a challenge, since both the Brazilian and international published literature is scarce in relation to the subject, which may limit the results of this research. From this, it can be said that this is a study of social, professional and academic relevance. Methods: A systematic literature review was conducted based on the guidelines of the PRISMA recommendation. The data collection process was performed in the CAPES, SciElo, Lilacs and PubMed databases from the descriptors selected for this research in December 2019. After selecting the articles, they were reviewed to collect data from this research, which It was based on the checklist proposed by the PRISMA method composed of 27 items and the flowchart composed of four steps that bring the information flow with the different phases of a systematic review. The selected articles were reviewed according to the research instruments collecting relevant information so that they could be analyzed considering their results and their contribution to this study. Thus, in the data collection process the objectives of this research were considered at all times. The selected articles were analyzed considering the following variables: Year of publication; language of publication; type of research; data approach; age of the patients; treatment time; and focus of results (technique efficiency, risks or complications). Conclusion: The results showed that only one selected article was written in Portuguese, all the others (6) were written in English, which confirms the scarcity of studies on the subject and points out the need for a greater number of approaches. The reliability of the selected articles is emphasized, considering that all presented a low risk of bias. The average age of patients who participated in the different surveys was 14 years, with a range from 19 months to 64 years. The shortest treatment time observed was 120 days, with 7 years as the maximum time reported by the authors. The authors identified the method as efficient, with low risks and with the main complications encountered, infection and recurrence of the problem. It was possible to conclude that the use of Hexapod external fixator has been shown to be effective in the treatment of patients with Blount’s disease, both in children and in older patients, however, its results are seen more quickly when treatment is started early, reducing treatment time, risks and complications.