Resumo A osteoartrite (OA) é caracterizada por uma degradação crônica, progressiva e irreversível da superfície articular, associada a inflamação articular. A principal etiologia da OA do tornozelo é pós-traumática e sua prevalência é maior entre os jovens e obesos. Apesar dos avanços no tratamento das fraturas ao redor do tornozelo, o risco geral de desenvolver OA pós-traumática do tornozelo após 20 anos do trauma é de quase 40%; especialmente nas fraturas bimaleolares de Weber tipo B e C e fraturas envolvendo a borda tibial posterior. Nas fraturas do tálus, essa prevalência se aproxima de 100%, dependendo da gravidade da lesão e do tempo de seguimento. Nesse cenário, é fundamental a compreensão atual das vias de sinalização moleculares envolvidas na senescência e apoptose dos condrócitos. O tratamento da OA do tornozelo é estagiado e guiado pelos sistemas de classificação, condições locais e do paciente. Os principais problemas são a limitada capacidade de regeneração da cartilagem articular, o baixo suprimento de sangue e a escassez de células-tronco progenitoras. A presente atualização resume evidências científicas básicas recentes da OA póstraumática do tornozelo, com foco principal nas alterações metabólicas da sinóvia, da cartilagem e do líquido sinovial. Epidemiologia, fisiopatologia, implicações clínicas, e opções de tratamento são também discutidas.

Abstract Osteoarthritis (OA) is characterized by a chronic, progressive and irreversible degradation of the joint surface associated with joint inflammation. The main etiology of ankle OA is post-traumatic and its prevalence is higher among young and obese people. Despite advances in the treatment of fractures around the ankle, the overall risk of developing posttraumatic ankle OA after 20 years is almost 40%, especially in Weber type B and C bimalleolar fractures and in fractures involving the posterior tibial border. In talus fractures, this prevalence approaches 100%, depending on the severity of the lesion and the time of follow-up. In this context, the current understanding of the molecular signaling pathways involved in senescence and chondrocyte apoptosis is fundamental. The treatment of ankle OA is staged and guided by the classification systems and local and patient conditions. The main problems are the limited ability to regenerate articular cartilage, low blood supply, and a shortage of progenitor stem cells. The present update summarizes recent scientific evidence of post-traumatic ankle OA with a major focus on changes of the synovia, cartilage and synovial fluid; as well as the epidemiology, pathophysiology, clinical implications, treatment options and potential targets for therapeutic agents.

RESUMO As fraturas do tornozelo e do pé representam 12% de todas as fraturas pediátricas. Fraturas maleolares são as lesões mais frequentes dos membros inferiores; fraturas do retropé e mediopé são raras, mas o seu tratamento inadequado pode resultar em síndrome de compartimento, deformidades tridimensionais, necrose avascular e osteoartrose pós-traumática precoce, as quais apresentam impacto significativo na função global do tornozelo e pé. Portanto, os desafios no tratamento dessas lesões na criança são o diagnóstico adequado e tratamento preciso para se evitarem as complicações. O objetivo do tratamento é restaurar a anatomia normal e a relação articular correta entre os ossos da região. Além disso, o tratamento deve ser planejado de acordo com acometimento articular, o alinhamento dos membros inferiores, a estabilidade ligamentar e a idade. O algoritmo de tratamento dos traumas complexos do tornozelo e pé na infância é descrito. Este artigo apresenta uma revisão sobre o tema e as evidências científicas para o tratamento adequado dessas lesões.

ABSTRACT Foot and ankle fractures represent 12% of all pediatric fractures. Malleolar fractures are the most frequent injuries of the lower limbs. Hindfoot and midfoot fractures are rare, but inadequate treatment for these fractures may results in compartment syndrome, three-dimensional deformities, avascular necrosis and early post-traumatic arthritis, which have a significant impact on overall foot and ankle function. Therefore, the challenges in treating these injuries in children are to achieve adequate diagnosis and precise treatment, while avoiding complications. The objective of the treatment is to restore normal anatomy and the correct articular relationship between the bones in this region. Moreover, the treatment needs to be planned according to articular involvement, lower-limb alignment, ligament stability and age. This article provides a review on this topic and presents the scientific evidence for appropriate treatment of these lesions.

ABSTRACT Objective: The aim of the study was to identify factors contributing to the development of non-union after fixation of diaphyseal humeral fractures using Hackethal's intramedullary nailing technique. Methods: In the time period from 2001 to 2010 156 patients with diaphyseal humeral fractures were treated surgically using Hackethal's technique. Six of them (3.8%) developed non-union. This group included three women and two men aged 63-69 years and one woman aged 37 years. The following parameters of the patients were recorded: age, gender, comorbidities, substance abuse, mechanism of injury, fracture type and location according to the AO/ASIF classification, and the operative technique. Results: A non-union developed in six patients treated with Hackethal´s method (3.8%). Five of six non-unions (83%) were observed in patients in their sixties. In the subgroup of sexagenarians, non-union developed in 20.8% of surgically treated patients, as compared to 3.8 % in entire group. In the union group, fractures have been caused by high energy trauma in 52% of patients. In patients who developed non-union, high energy trauma caused 67% of fractures. With correct surgical technique the development of a non-union was observed in 0.7% of patients, with incorrect technique in 35.7% (p<0.001). Conclusion: Treatment of diaphyseal humeral fractures with Hackethal's intramedullary elastic bundle nailing resulted in an overall high union rate. Factors contributing to the development of non-union were extension of this method to AO type B3 and C fractures and technical imperfection during implantation. Level of Evidence III, Prospective, Case-Control Study.