Determination of the incidence, mechanisms, and diagnosis of hand complications after radial artery (RA) harvesting in coronary surgery (CABG). The study group (RA group) includes 54 patients who underwent RA harvesting in CABG operation. The control group (noRA group) consists of 131 patients who underwent CABG without the use of RA graft. The average follow-up time was 16.36 +/- 5.13 months. The patients were examined clinically, (a) for motor function abnormalities associated with radial and median nerve damage and (b) for sensory abnormalities, and the function of radial nerve was determined by eliciting the brachioradialis reflex. They answered in a formal scripted questionnaire to elicit symptoms and clinical points attributable to nerve damage during RA harvest, such as hand weakness, thumb weakness, sensation abnormalities on the back and on the palm side of the forearm, hand numbness, hand-reversible paresis or forearm infection postoperatively, and any other upper limb abnormality. Of the patients in the RA group, 34.09% reported left-hand abnormality after operation. On the other hand, in the noRA group left-hand abnormality was reported in 18.68% of patients. In the RA group sensation abnormality was reported in 34.09% of patients and thumb weakness alone was reported in 6.82% of patients. There was a statistically significant difference between the two groups. Low EuroSCORE was the predicting factor for motor abnormalities. More knowledge has been added about the neurologic complications after RA harvesting lately. We demonstrated the rate of motor and sensory abnormality, the potential mechanisms of these complications caused by surgical trauma or devascularization, and any predictive factors of complications. Optimal surgical techniques to avoid the damage of the responsible nerves are recommended.