OBJECTIVES: The main objective of this study was to determine whether infrared thermography could be used as an efficient technique to evaluate the impact of a birth-related brachial plexus injury on the temperature of the injured arm and whether it could be used as a complementary method when diagnosing this injury in clinical praxis. BACKGROUND: Clinically, the brachial plexus injury is a peripheral paresis, which occurs when nerves that send signals from the spinal cord to the shoulder, arm, and hand are stretched or compressed. In principle, the brachial plexus injury, as a long-lasting injury, should be causing hypothermia of the injured arm. METHODS: The usage of contactless infrared thermography could offer a “new view” of the diagnostic process in this case. The present study, therefore, describes a process of clinical infrared thermography examination of three patients of different age and presents results from those examinations. RESULTS AND CONCLUSION: From our results, it can be confirmed that the birth-related brachial plexus injury affects the temperature of the affected arm, especially in the area of the cubital fossa, to an extent that the thermal camera is capable of detecting significant temperature differences between the healthy and injured arms (Tab. 3, Fig. 7, Ref. 13).