Third Finger (third + finger)

Distribution by Scientific Domains


Selected Abstracts


Rapid functional plasticity in the primary somatomotor cortex and perceptual changes after nerve block

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2004
Thomas Weiss
Abstract The mature human primary somatosensory cortex displays a striking plastic capacity to reorganize itself in response to changes in sensory input. Following the elimination of afferent return, produced by either amputation, deafferentation by dorsal rhizotomy, or nerve block, there is a well-known but little-understood ,invasion' of the deafferented region of the brain by the cortical representation zones of still-intact portions of the brain adjacent to it. We report here that within an hour of abolishing sensation from the radial and medial three-quarters of the hand by pharmacological blockade of the radial and median nerves, magnetic source imaging showed that the cortical representation of the little finger and the skin beneath the lower lip, whose intact cortical representation zones are adjacent to the deafferented region, had moved closer together, presumably because of their expansion across the deafferented area. A paired-pulse transcranial magnetic stimulation procedure revealed a motor cortex disinhibition for two muscles supplied by the unaffected ulnar nerve. In addition, two notable perceptual changes were observed: increased two-point discrimination ability near the lip and mislocalization of touch of the intact ulnar portion of the fourth finger to the neighbouring third finger whose nerve supply was blocked. We suggest that disinhibition within the somatosensory system as a functional correlate for the known enlargement of cortical representation zones might account for not only the ,invasion' phenomenon, but also for the observed behavioural correlates of the nerve block. [source]


A case of nevus comedonicus syndrome associated with neurologic and skeletal abnormalities

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2001
Young-Joon Seo MD
A 12-year-old male was referred to us with recurrent pus discharge from tender nodules on the right axilla dating from the neonatal period. The nodules were black, characterized by scarring with dilated follicular openings and there were black papules filled with comedo-like keratin plugs in both axillae. Physical examination revealed a bowing deformity of the right third finger and retardation in language ability. The patient was referred to the Departments of Neurology and Orthopedics in Chungnam National University Hospital, Korea. Histologic examination of one of the black comedo-like lesions showed a bulbous and dilated infundibulum that contained laminated keratin, indicating a diagnosis of nevus comedonicus. A CT scan of the brain revealed dysgenesis of the corpus callosum. The IQ (intelligence quotient) score of the patient, measured by the Korean Wechsler Intelligence Scale for Children-Revised, was 94. The only difficulty noted for ordinary life was learning language. A radiograph of the right hand revealed hyperextension and an ulnar drift deformity of the right middle finger. Corrective osteotomy with external fixation and an iliac bone autograft were performed. Intermittent neurologic follow-up visits were ordered for the noted language deficit. At present the patient only exhibits difficulty in calculation. Oral antibiotics were administered to the skin lesions on occasion for secondary infections and inflammation of the cysts and comedones. Extraction of the comedones was performed as needed. [source]


Specialized use of two fingers in free-ranging aye-ayes (Daubentonia madagascariensis)

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 8 2008
Stanislav Lhota
Abstract The aye-aye (Daubentonia madagascariensis) possesses a highly specialized hand with two fingers, the third and the fourth, being used in a way unparalleled by any other primate. We observed the use of the third and the fourth fingers in various activities in four free-ranging aye-ayes. We found that the thin third finger was used exclusively or preferably for tapping, inserting into the mouth (probably for cleaning the teeth) and probing for nectar, kernels and insects in bamboo, twigs and live wood. In contrast, the robust fourth finger was used preferably when eating jackfruit (Artocarpus heterophyllus). When probing for invertebrates in soft plant tissues and in dead wood, both fingers were used in high proportions. To extract the contents from coconuts, the two fingers were apparently used for different tasks. From this small (686 observations), but unique, study of free-ranging aye-ayes, we conclude that the third finger appears to be specialized for use in tasks requiring high mobility, sensitivity and precision, whereas the fourth finger appears to be specialized for tasks requiring strength, scooping action and deep access. Am. J. Primatol. 70:786,795, 2008. © 2008 Wiley-Liss, Inc. [source]


A case of tenosynovial chondromatosis with tophus-like deposits,

APMIS, Issue 9 2004
Case report
Tenosynovial chondromatosis has not been well recognized because of its rarity, but it is clinically important because of its high rate of recurrence. We report here a case of tenosynovial chondromatosis with deposits of crystalline material that appeared to be sodium urate (gouty tophi). A 37-year-old Japanese man was admitted because of a hard mass in his left third finger. He had undergone surgery at the same anatomical site four and seven years previously. The roentgenogram revealed a soft tissue mass in the flexor aspect of the proximal phalanx. At operation, the tumor was found to have arisen in the tendon sheath. Histopathological examination showed that the tumor was composed of well-defined, multiple, cartilaginous nodules that were surrounded by tenosynovial tissue. A few of the nodules were calcified. The chondrocytes had mild atypia, and were immunopositive for S-100 protein. A diagnosis of tenosynovial chondromatosis was made. The nodules also contained crystalline deposits, which bore a histological resemblance to gouty tophi. We were unable to define the exact nature of these deposits even by transmission electron microscopy and electron roentgenographic microanalysis. Crystalline deposits in chondromas of soft tissue have been reported but not in tenosynovial chondromatosis. [source]


Abnormal peripheral vascular response to occlusion provocation in normal tension glaucoma patients

ACTA OPHTHALMOLOGICA, Issue 2007
J WIERZBOWSKA
Purpose: To assess peripheral vascular reactive hyperemia in response to occlusion provocation test, using two-channels laser Doppler probe in patients with normal tension glaucoma (NTG) and normal subjects. Methods: 15 patients with NTG (12 women and 4 men), mean aged 58,9 and 15 control subjects (13 women and 2 men), mean aged 60,6 were subjected to an occlusion test. The experiment comprised following steps: 1/ a 5-minute baseline-period 2/ a 2-minute occlusion of the left hand using a 15 cm wide cuff located directly over the elbow (the pressure in the cuff was 50 mmHg higher than the systolic pressure measured on the arm 3/ a 15- minute final recovery period after occlusion. Finger hyperemia was assessed by two-channels laser-Doppler flowmeter MBF-3d, Moor Instruments, Ltd., continuously during the experiment. For measurements of hyperemia two surface probes were attached to the pulp of the second finger (mean probe) and third finger (basic probe) of the left hand. The following hyperemia parameters were measured: RF (rest flow), BZ (biological zero), TM (time to peak flow), TH (half-time of hyperemia), MAX (maximum of hyperemia) and hyperemia amplitude (MAX-RF)/RF 100% was calculated. Kruskal-Wallis test analysis was used to test the differences between the group of patients and normal subjects for TM1,MXF1 (basic probe) and TM2, MXF2 (mean probe) parameters. Results: In NTG patients, TM1 was significantly higher comparing with healthy subjects whereas MAX was significantly lower as compared to the control group. Conclusions: Occlusion provocation test elicits a different systemic hyperemia response in patients with NTG compared with healthy subjects. [source]