RESUMO
INTRODUCTION: Connections are common communications between 2similar anatomical elements. Some of the most common are in the forearm between the median and ulnar nerves and are clinically important because they produce variations in motor and sensory innervation and can cause confusion when diagnosing peripheral nerve pathology. METHOD: Descriptive, cross-sectional, observational study. A total of 127 patients older than 18 years were studied, electromyography was performed on the upper limbs and the frequency of presentation of the connections was obtained. RESULT: The Riche-Cannieu connection was present in 16.5% of the total patients studied, of which 42.9% presented in the left arm and 89.3% in isolation. The Marinacci connection was the second in frequency with 15.7%, of which 40% was presented in the left arm and 45.8% coexisted with another connection. The Berrettini connection was the third in frequency with 9.4%, 50% presented in the left arm and 53.3% of the sample was found in isolation. Martin-Grüber's connection was the least frequent at 7.1% of our cases, of which 44.5% presented bilaterally and 90% associated with another connection. CONCLUSION: It is concluded that of the 4types of connection studied the most frequent in our environment was the Riche-Cannieu with predominance of the left arm and in isolation.