Body size and scaling of the hands and feet of prosimian primates

The hands and feet of primates fulfill a variety of biological roles linked with food acquisition and positional behavior. Current explanations of shape differences in cheiridial morphology among prosimians are closely tied to body size differences. Although numerous studies have examined the relationships between body mass and limb morphology in prosimians, no scaling analysis has specifically considered hand and foot dimensions and intrinsic proportions. In this study, we present such an analysis for a sample of 270 skeletal specimens distributed over eight prosimian families. The degree of association between size and shape was assessed using nonparametric correlational techniques, while the relationship between each ray element length and body mass (from published data and a body mass surrogate) was tested for allometric scaling. Since tarsiers and strepsirrhines encompass many taxa of varying degrees of phylogenetic relatedness, effective degrees of freedom were calculated, and comparisons between families were performed to partially address the problem of statistical nonindependence and "phylogenetic inertia." Correlational analyses indicate negative allometry between relative phalangeal length (as reflected by phalangeal indices) and body mass, except for the pollex and hallux. Thus, as size increases, there is a significant decrease in the relative length of the digits when considering all prosimian taxa sampled. Regression analyses show that while the digital portion of the rays scales isometrically with body mass, the palmar/plantar portion of the rays often scales with positive allometry. Some but not all of these broadly interspecific allometric patterns remain statistically significant when effective degrees of freedom are taken into account. As is often the case in interspecific scaling, comparisons within families show different scaling trends in the cheiridia than those seen across families (i.e., lorisids, indriids, and lemurids exhibit rather different allometries). The interspecific pattern of positive allometry that appears to best characterize the metapodials of prosimians, especially those of the foot, parallels differences found in the morphology of the volar skin. Indeed, relatively longer metapodials appear to covary with flatter and more coalesced volar pads, which in turn slightly improve frictional force for animals that are at a comparative disadvantage while climbing because of their larger mass. Despite the essentially isometric relationship found between digit length and body mass across prosimians, examination of the residual variation reveals that tarsiers and Daubentonia possess, relative to their body sizes, remarkably long fingers. Such marked departures between body size and finger length observed in these particular primates are closely linked with specialized modes of prey acquisition and manipulation involving the hands.     

Pompholyx (Epidermophytosis,Dermatophytosis, Ringworm of the feet,infectious eczematoid dermatitis or ringworm,dyshidrosis)

Summary Pompholyx as the oldest term for this disease in medical terminology, connoting a recurrent vesicular eruption on palms and soles, is recommended for general use in replacing a number of prejudicial terms connecting this condition either with a hypothetical and long reputed dysfunction of the sweat glands: dyshidrosis or with the causative role of fungi: epidermophytosis.Publications of statistical investigations pertaining to the subject are reviewed. They show the amazing low percentage of pathogenic fungi which could be recovered in this condition.Among clinically active cases, the lesions were microscopically negative in the ratio of 10% to 37%.Clinically active and microscopically fungus-positive cases yielded from 80% to 95 % negative cultural results.The present study of 983 cases showed 1.9% clinically active lesions on the feet. Microscopically and culturally all these cases were negative for any kind of pathogenic fungi.During the camping period in mid-summer 1940, from June to late August, no prophylactic measures were taken to kill the fungi or to prevent their dissemination in locker rooms, on runways or shower rooms.Despite this attitude there was no spread of fungi, no dissemination of infecting agents and no outburst of an epidemic of epidermophytosis.     

Epidermal patterns of the hands and feet of the pygmy chimpanzee (Pan paniscus)

The characteristics of the epidermal ridge system were studied in a series of eighteen lesser or pygmy chimpanzees (Pan paniscus). The general ridge alignments are very similar to those of the chimpanzee (Pan troglodytes); Biegert ('61). On the average the pattern intensity (P.I.) of the palm configurations is considerably higher in the pygmy chimpanzee than in the chimpanzee, thus representing the highest total palm pattern intensity of all species of the Hominoidea. The sole configurations show parallel main results to those of the palm; however, the decreased sole pattern frequency of the pygmy chimpanzee is of a smaller predominance only as compared to the values of the other species of this superfamily. The preliminary data on the finger tip patterns, translated into P.I. values, are much higher than in chimpanzees and within the range of the mean values of gorillas (Brehme, '73), while those of the toes of pygmy chimpanzees seem to possess the lowest P.I. values of the African apes.     

Treatment of the hands and feet in Apert syndrome: an evolution in management

Apert syndrome is a relatively uncommon condition that is instantly recognizable on the basis of the pan-syndactylies involving both the hands and feet. For more than 10 years, the treatment of Apert syndrome hand and foot anomalies was approached in a comprehensive manner, with attempts to maximize the final results and minimize the total number of operations. Numerous conventions were abandoned in the development of this approach, with the introduction of some new methodologies, including (1) release of all 10 fingers, and toes, in only two operations, (2) elimination of routine digital amputations, (3) abandonment of the zigzag incision in favor of straight-line release, (4) substitution of equal-length anterior and posterior flaps for the long dorsal web space lining flap, (5) leaving of small areas of exposed bone without vascularized tissue coverage, and (6) performance of midphalangeal osteotomies, among older children, to improve hand function. Fifty-seven children with Apert syndrome have been treated at the author's center since 1990, and 43 underwent surgical treatment of their hands and feet by a single surgeon. Treatment can be separated into two phases, early (syndactyly releases) and late (functional osteotomies). Seventeen of those 43 patients were treated at the author's center from birth (type I, 11 patients; type II, two patients; type III, four patients), and 10 fingers and 10 toes were achieved for all patients in two operations. No digital amputations were performed for any of the 43 patients. However, four of 26 patients (15 percent) not treated at the author's center from birth had undergone at least one digital amputation before coming to the center. Twenty-two of those 26 patients required a two-stage syndactyly release to accomplish the separation of all 10 fingers and toes. Aside from the patients who had previously undergone amputations, all other patients successfully achieved 10 fingers and toes, except for one patient (38 of 39 patients, 97 percent). The average operative time for the first-stage syndactyly release of the hands and feet was 4 hours 11 minutes (range, 185 to 300 minutes), and that for the second stage was 3 hours 49 minutes (range, 160 to 300 minutes). Twenty-eight hands were treated with functional osteotomies, which involved permanent angulation of the fused phalanges at the proximal interphalangeal level, to create a "position of function" and provide pulp-to-pulp pinch. In addition, targeted osteotomies of the feet were performed for many of these patients, to decrease pain with walking. There were no major complications. Minor complications included one reexploration because of bleeding, early in the series. There were 13 incomplete secondary syndactylies that required a subsequent operative release (10 spaces treated at the author's center and three treated elsewhere), of a total of 342 spaces (3 percent author incidence). There were no scar contractures or functional limitations that required release. This distinctive protocol seemed to result in improved functional outcomes, with a reduction in the total number of operative procedures.     

The hands and feet of Archaeolemur: metrical affinities and their functional significance

Recent expeditions to Madagascar have recovered abundant skeletal remains of Archaeolemur, one of the so-called "monkey lemurs" known from Holocene deposits scattered across the island. These new skeletons are sufficiently complete to permit reassembly of entire hands and feet--postcranial elements crucial to drawing inferences about substrate preferences and positional behavior. Univariate and multivariate analysis of intrinsic hand and foot proportions, phalangeal indices, relative pollex and hallux lengths, phalangeal curvature, and distal phalangeal shape reveal a highly derived and unique morphology for an extinct strepsirrhine that diverges dramatically from that of living lemurs and converges in some respects on that of Old World monkeys (e.g., mandrills, but not baboons or geladas). The hands and feet of Archaeolemur are relatively short (extremely so relative to body size); the carpus and tarsus are both "long" relative to total hand and foot lengths, respectively; phalangeal indices of both the hands and feet are low; both pollex and hallux are reduced; the apical tufts of the distal phalanges are very broad; and the proximal phalanges are slightly curved (but more so than in baboons). Overall grasping capabilities may have been compromised to some extent, and dexterous handling of small objects seems improbable. Deliberate and noncursorial quadrupedalism was most likely practiced on both the ground and in the trees. A flexible locomotor repertoire in conjunction with a eurytopic trophic adaptation allowed Archaeolemur to inhabit much of Madagascar and may explain why it was one of the latest surviving subfossil lemurs.     

Aplasics born without hands mirror the goal of hand actions with their feet

The premotor and parietal mirror neuron system (MNS) is thought to contribute to the understanding of observed actions by mapping them onto "corresponding" motor programs of the observer [1-24], but how would the MNS respond to the observation of hand actions if the observer never had hands? Would it not show changes of blood-oxygen-level dependent (BOLD) signal, because the observer lacks motor programs that can resonate [12, 25, 26], or would it show significant changes because the observer has motor programs for the foot or mouth with corresponding goals [15, 17, 19, 27, 28]? We scanned two aplasic subjects, born without arms or hands, while they watched hand actions and compared their brain activity with that of 16 control subjects. All subjects additionally executed actions with different effectors (feet, mouth, and, for controls, hands). The BOLD signal of aplasic individuals within the putative MNS was augmented when they watched hand actions, demonstrating the brain's capacity to mirror actions that deviate from the embodiment of the observer by recruiting voxels involved in the execution of actions that achieve corresponding goals by different effectors. This sheds light on the functional organization of the MNS and predominance of goals in imitation.     

Pompholyx of the nail organ and the true onychomycosis

Pompholyx is one clinical form of the endoparasitic-hematogenous skin eruptions. It is characterized by sago-grain-like, deeply embedded blisters or pustules within the normal, primarily non-inflamed skin, localized to the palms, soles, fingers, toes and interdigital webs, and in the nail organ. The blisters may be located in the nail wall causing paronychia, and/or beneath the nail plate causing onychia. The discussion of the etiology and pathogenesis of the pompholyx of the nail organ is inseparable from pompholyx at other sites (e.g. palms and soles), since they are identical. Hence, the term pompholyx should replace such misleading terms as infectious eczematoid dermatitis, id eruption, of the hand and/or feet, dermato- or epidermophytosis, dyshidrosis, and the vernacular athlete's foot. Even though hyphomycetes (true pathogens and common molds) of many sorts may be detected in the roof of the blisters, particularly on the feet, and scrapings of detritus from the nails, they have no role in the etiology or pathogenesis of this condition. Due to an universal infection immunity pompholyx is not infectious or transmissible. True onychomycosis is clinically and pathogenetically an entirely different condition. The purpose of this paper is to clarify the fundamental differences in etiology and pathogenesis between the two conditions.     

Acrodysplasia (hands and feet) with scoliosis, by autosomal recessive transmission

Brachydactyly is reported in two brothers born to consanguineous parents (1/8). Additional abnormal features were scoliosis, spina bifida occulta, and carpal synostosis.     

The community of human malformation syndromes that shares ectodermal dysplasia and deformities of the hands and feet.

Syndromes of human congenital malformation may be classified be recognizing communities of syndromes that share multiple phenotypic similarities involving their principal diagnostic features. A community of syndromes that shares various expressions of ectodermal dysplasia and various deformities of the hands and feet is proposed; these syndromes are divisible into two classes according to the presence or absence of anomalies in the nasal or labial regions of the face. The dysmorphogenetic validity of the division is supported by the fact that the syndromes without nasal or labial anomalies have a high frequency of sensorineural deafness as one expression of ectodermal dysplasia whereas those without such anomalies do not. The usefulness of such a syndromal community as a base for evolving a taxonomic scheme of dysmorphogenetic relatedness amongst different syndromes is illustrated.     

Functional reconstruction of both hands by free transfer of combined second and third toes from both feet

The correction of severe trauma to both hands by two major microsurgical operations and additional minor interventions on the already functioning transplants is described. The excision of combined second and third toes as transplants inflicts an injury on the foot, but for our patient this iatrogenic trauma was justified. Careful investigation of the feet after transfer shows that their condition does not significantly impair the quality of the patient's life. The special importance of the patient's desire to regain his or her abilities and to collaborate with the medical staff is emphasized.