[Reassessment of the Luria's fist-edge-palm test]

In clinical practice, we often use the Luria's fist edge-palm test (FEP) to detect frontal lobe dysfunction. However, we have sometimes encountered patients with failure in this test following posterior lesions. The aim of our study is to evaluate the sensitivity of this test to frontal lobe damage and to clarify the relationship between the FEP performance and other neuropsychological findings. Forty brain-damaged patients (mean age: 61.7 years) were studied. Thirty-four patients were right-handed and 6 non right-handed. Their lesions were confirmed by CT or MRI scan. Following six tests were performed; 1) imitation of single hand posture, 2) imitation of a sequence of two hand postures (fist-edge), 3) imitation of a sequence of three and postures (FEP), 4) copying a cube, 5) serial drawing, and 6) verbal and non-verbal short-term memory span. Imitation of hand postures were performed with non-paralytic hand. Twenty-four patients, i.e., 60% of the patients tested, failed to perform the FEP sequence. The failure was significantly correlated with the presence of constructional disability, perseveration and short-term memory impairment. There was significant relationship between the failure the FEP and frontal lobe damage. However, we found five patients without frontal lesion who failed in performing the FEP. We conclude that we should be careful in associating the failure in the FEP with frontal lobe damage, although this test is sensitive to brain dysfunction.