PATELLA FRACTURES, EPIDEMIOLOGY, ANATOMY, FUNCTION, MECHANISMS OF ACTION, CLASSIFICATION, CLINICAL PRESENTATION, IMAGING PRESENTATION, TREATMENT AND COMPLICATIONS

Introduction: The patella has a great importance in the extension and flexion activities of the knee, being paramount in the patient's quality of life. Nowadays the surgical options that stand out the most are open reduction plus internal fixation and resection of the patella. The patella increases the leverage of the quadriceps. Management following patella injury has been based on preservation of bone and vascular supply, in addition to joint restoration and extensor function. In patella fractures, it is essential to reflect on the biomechanics of the bone and the fixation technique to be used. Objective: to detail the current information related to patella fractures, epidemiology, anatomy, function, mechanisms of action, classification, clinical presentation, imaging presentation, treatment and complications. Methodology: a total of 32 articles were analyzed in this review, including review and original articles, as well as clinical cases, of which 24 bibliographies were used because the other articles were not relevant for this study. The sources of information were PubMed, Google Scholar and Cochrane; the terms used to search for information in Spanish, Portuguese and English were: patella, patellar fractures, knee trauma. Results: Patellar fractures comprise 1% of all fractures in humans, with a 2:1 male to female ratio. They occur more frequently in individuals between 20 and 50 years of age. The frequencies of pseudarthrosis and infection are relatively lower after the surgical procedure. Approximately 2 to 7% of patellar fractures are open fractures. Their classification is descriptive. Conclusions: The patella is the largest sesamoid bone in the human body with several important functions. Frequently, patellar fractures appear after falls on the knee, blows and unexpected and energetic muscular pulls. The diagnosis is made by means of clinical history, physical examination and complementary radiography. Anteroposterior and lateral projections of the knee should be performed. For conservative treatment it is essential that the knee extensor mechanism is intact. There are several methods of surgical treatment, in general the open reduction and internal fixation present good results. Complications include post-traumatic osteoarthritis, alteration or loss of mobility of the knee, refracture, fixation failure, osteonecrosis, intolerance to osteosynthesis material, loss of strength of the extensor mechanism, loss of extension, instability of the patella and pseudoarthrosis. KEY WORDS: patella, knee, fracture, treatment, osteosynthesis.