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Dunmore CJ, Bardo A, Skinner MM, Kivell TL. Trabecular variation in the first metacarpal and manipulation in hominids. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 171:219-241. [PMID: 31762017 DOI: 10.1002/ajpa.23974] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 10/27/2019] [Accepted: 10/29/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVES The dexterity of fossil hominins is often inferred by assessing the comparative manual anatomy and behaviors of extant hominids, with a focus on the thumb. The aim of this study is to test whether trabecular structure is consistent with what is currently known about habitually loaded thumb postures across extant hominids. MATERIALS AND METHODS We analyze first metacarpal (Mc1) subarticular trabecular architecture in humans (Homo sapiens, n = 10), bonobos (Pan paniscus, n = 10), chimpanzees (Pan troglodytes, n = 11), as well as for the first time, gorillas (Gorilla gorilla gorilla, n = 10) and orangutans (Pongo sp., n = 1, Pongo abelii, n = 3 and Pongo pygmaeus, n = 5). Using a combination of subarticular and whole-epiphysis approaches, we test for significant differences in relative trabecular bone volume (RBV/TV) and degree of anisotropy (DA) between species. RESULTS Humans have significantly greater RBV/TV on the radiopalmar aspects of both the proximal and distal Mc1 subarticular surfaces and greater DA throughout the Mc1 head than other hominids. Nonhuman great apes have greatest RBV/TV on the ulnar aspect of the Mc1 head and the palmar aspect of the Mc1 base. Gorillas possessed significantly lower DA in the Mc1 head than any other taxon in our sample. DISCUSSION These results are consistent with abduction of the thumb during forceful "pad-to-pad" precision grips in humans and, in nonhuman great apes, a habitually adducted thumb that is typically used in precision and power grips. This comparative context will help infer habitual manipulative and locomotor grips in fossil hominins.
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Affiliation(s)
- Christopher J Dunmore
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Ameline Bardo
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Matthew M Skinner
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Tracy L Kivell
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Dunmore CJ, Kivell TL, Bardo A, Skinner MM. Metacarpal trabecular bone varies with distinct hand-positions used in hominid locomotion. J Anat 2019; 235:45-66. [PMID: 31099419 PMCID: PMC6580057 DOI: 10.1111/joa.12966] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/22/2019] [Indexed: 12/11/2022] Open
Abstract
Trabecular bone remodels during life in response to loading and thus should, at least in part, reflect potential variation in the magnitude, frequency and direction of joint loading across different hominid species. Here we analyse the trabecular structure across all non-pollical metacarpal distal heads (Mc2-5) in extant great apes, expanding on previous volume of interest and whole-epiphysis analyses that have largely focused on only the first or third metacarpal. Specifically, we employ both a univariate statistical mapping and a multivariate approach to test for both inter-ray and interspecific differences in relative trabecular bone volume fraction (RBV/TV) and degree of anisotropy (DA) in Mc2-5 subchondral trabecular bone. Results demonstrate that whereas DA values only separate Pongo from African apes (Pan troglodytes, Pan paniscus, Gorilla gorilla), RBV/TV distribution varies with the predicted loading of the metacarpophalangeal (McP) joints during locomotor behaviours in each species. Gorilla exhibits a relatively dorsal distribution of RBV/TV consistent with habitual hyper-extension of the McP joints during knuckle-walking, whereas Pongo has a palmar distribution consistent with flexed McP joints used to grasp arboreal substrates. Both Pan species possess a disto-dorsal distribution of RBV/TV, compatible with multiple hand postures associated with a more varied locomotor regime. Further inter-ray comparisons reveal RBV/TV patterns consistent with varied knuckle-walking postures in Pan species in contrast to higher RBV/TV values toward the midline of the hand in Mc2 and Mc5 of Gorilla, consistent with habitual palm-back knuckle-walking. These patterns of trabecular bone distribution and structure reflect different behavioural signals that could be useful for determining the behaviours of fossil hominins.
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Affiliation(s)
- Christopher J. Dunmore
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
| | - Tracy L. Kivell
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Ameline Bardo
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
| | - Matthew M. Skinner
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
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Three-dimensional geometric morphometric analysis of the first metacarpal distal articular surface in humans, great apes and fossil hominins. J Hum Evol 2019; 132:119-136. [DOI: 10.1016/j.jhevol.2019.04.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 04/23/2019] [Accepted: 04/23/2019] [Indexed: 11/18/2022]
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Georgiou L, Kivell TL, Pahr DH, Buck LT, Skinner MM. Trabecular architecture of the great ape and human femoral head. J Anat 2019; 234:679-693. [PMID: 30793309 PMCID: PMC6481414 DOI: 10.1111/joa.12957] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2019] [Indexed: 11/27/2022] Open
Abstract
Studies of femoral trabecular structure have shown that the orientation and volume of bone are associated with variation in loading and could be informative about individual joint positioning during locomotion. In this study, we analyse for the first time trabecular bone patterns throughout the femoral head using a whole-epiphysis approach to investigate how potential trabecular variation in humans and great apes relates to differences in locomotor modes. Trabecular architecture was analysed using microCT scans of Pan troglodytes (n = 20), Gorilla gorilla (n = 14), Pongo sp. (n = 5) and Homo sapiens (n = 12) in medtool 4.1. Our results revealed differences in bone volume fraction (BV/TV) distribution patterns, as well as overall trabecular parameters of the femoral head between great apes and humans. Pan and Gorilla showed two regions of high BV/TV in the femoral head, consistent with hip posture and loading during two discrete locomotor modes: knuckle-walking and climbing. Most Pongo specimens also displayed two regions of high BV/TV, but these regions were less discrete and there was more variability across the sample. In contrast, Homo showed only one main region of high BV/TV in the femoral head and had the lowest BV/TV, as well as the most anisotropic trabeculae. The Homo trabecular structure is consistent with stereotypical loading with a more extended hip compared with great apes, which is characteristic of modern human bipedalism. Our results suggest that holistic evaluations of femoral head trabecular architecture can reveal previously undetected patterns linked to locomotor behaviour in extant apes and can provide further insight into hip joint loading in fossil hominins and other primates.
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Affiliation(s)
- Leoni Georgiou
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
| | - Tracy L. Kivell
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Dieter H. Pahr
- Institute for Lightweight Design and Structural BiomechanicsVienna University of TechnologyViennaAustria
- Department of Anatomy and BiomechanicsKarl Landsteiner Private University of Health SciencesKrems an der DonauAustria
| | - Laura T. Buck
- Department of AnthropologyUniversity of CaliforniaDavisCAUSA
| | - Matthew M. Skinner
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
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Neufuss J, Robbins MM, Baeumer J, Humle T, Kivell TL. Manual skills for food processing by mountain gorillas (Gorilla beringei beringei) in Bwindi Impenetrable National Park, Uganda. Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly071] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Johanna Neufuss
- Animal Postcranial Evolution (APE) Laboratory, Skeletal Biology Research Centre, School of Anthropology & Conservation, University of Kent, Canterbury, UK
| | - Martha M Robbins
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Jana Baeumer
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Tatyana Humle
- Durrell Institute of Conservation and Ecology, School of Anthropology & Conservation, University of Kent, Canterbury, UK
| | - Tracy L Kivell
- Animal Postcranial Evolution (APE) Laboratory, Skeletal Biology Research Centre, School of Anthropology & Conservation, University of Kent, Canterbury, UK
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Samuel DS, Nauwelaerts S, Stevens JMG, Kivell TL. Hand pressures during arboreal locomotion in captive bonobos (Pan paniscus). J Exp Biol 2018. [DOI: 10.1242/jeb.170910] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Evolution of the human hand has undergone a transition from use during locomotion to use primarily for manipulation. Previous comparative morphological and biomechanical studies have focused on potential changes in manipulative abilities during human hand evolution, but few have focused on functional signals for arboreal locomotion. Here, we provide this comparative context though the first analysis of hand loading in captive bonobos during arboreal locomotion. We quantify pressure experienced by the fingers, palm and thumb in bonobos during vertical locomotion, suspension and arboreal knuckle-walking. Results show that pressure experienced by the fingers is significantly higher during knuckle-walking compared with similar pressures experienced by the fingers and palm during suspensory and vertical locomotion. Peak pressure is most often experienced at or around the third digit in all locomotor modes. Pressure quantified for the thumb is either very low or absent, despite the thumb making contact with the substrate during all suspensory and vertical locomotor trials. Unlike chimpanzees, the bonobos do not show a rolling pattern of digit contact with the substrate during arboreal knuckle-walking but, instead, digits 3 and 4 typically touch down first and digit 5 almost always made contact with the substrate. These results have implications for interpreting extant and fossilised hand morphology; we expect bonobo (and chimpanzee) bony morphology to primarily reflect the biomechanical loading of knuckle-walking, while functional signals for arboreal locomotion in fossil hominins are most likely to appear in the fingers, particularly digit 3, and least likely to appear in the morphology of the thumb.
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Affiliation(s)
- Diana S. Samuel
- Animal Postcranial Evolution (APE) Lab, Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury CT2 7NR, UK
| | - Sandra Nauwelaerts
- Laboratory for Functional morphology, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
- Centre for Research and Conservation (CRC), Koningin Astridplein 20-26, 2018 Antwerp, Belgium
| | - Jeroen M. G. Stevens
- Centre for Research and Conservation (CRC), Koningin Astridplein 20-26, 2018 Antwerp, Belgium
- Behavioral Ecology and Ecophysiology group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Tracy L. Kivell
- Animal Postcranial Evolution (APE) Lab, Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury CT2 7NR, UK
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig 04103, Germany
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Neufuss J, Robbins MM, Baeumer J, Humle T, Kivell TL. Comparison of hand use and forelimb posture during vertical climbing in mountain gorillas (Gorilla beringei beringei) and chimpanzees (Pan troglodytes). AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 164:651-664. [PMID: 28872656 DOI: 10.1002/ajpa.23303] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 08/01/2017] [Accepted: 08/14/2017] [Indexed: 11/11/2022]
Abstract
OBJECTIVES Studies on grasping and limb posture during arboreal locomotion in great apes in their natural environment are scarce and thus, attempts to correlate behavioral and habitat differences with variation in morphology are limited. The aim of this study is to compare hand use and forelimb posture during vertical climbing in wild, habituated mountain gorillas (Gorilla beringei beringei) and semi-free-ranging chimpanzees (Pan troglodytes) to assess differences in the climbing styles that may relate to variation in hand or forelimb morphology and body size. MATERIALS AND METHODS We investigated hand use and forelimb posture during both ascent and descent vertical climbing in 15 wild mountain gorillas and eight semi-free-ranging chimpanzees, using video records obtained ad libitum. RESULTS In both apes, forelimb posture was correlated with substrate size during both ascent and descent climbing. While climbing, both apes used power grips and diagonal power grips, including three different thumb postures. Mountain gorillas showed greater ulnar deviation of the wrist during vertical descent than chimpanzees, and the thumb played an important supportive role when gorillas vertically descended lianas. DISCUSSION We found that both apes generally had the same grip preferences and used similar forelimb postures on supports of a similar size, which is consistent with their overall similarity in hard and soft tissue morphology of the hand and forelimb. However, some species-specific differences in morphology appear to elicit slightly different grasping strategies during vertical climbing between mountain gorillas and chimpanzees.
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Affiliation(s)
- Johanna Neufuss
- Animal Postcranial Evolution (APE) Laboratory, Skeletal Biology Research Centre, School of Anthropology & Conservation, University of Kent, Canterbury, United Kingdom
| | - Martha M Robbins
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Jana Baeumer
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Tatyana Humle
- Durrell Institute of Conservation and Ecology, School of Anthropology & Conservation, University of Kent, Canterbury, United Kingdom
| | - Tracy L Kivell
- Animal Postcranial Evolution (APE) Laboratory, Skeletal Biology Research Centre, School of Anthropology & Conservation, University of Kent, Canterbury, United Kingdom.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Grover AK, Samson SE. Benefits of antioxidant supplements for knee osteoarthritis: rationale and reality. Nutr J 2016; 15:1. [PMID: 26728196 PMCID: PMC4700773 DOI: 10.1186/s12937-015-0115-z] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 12/21/2015] [Indexed: 01/17/2023] Open
Abstract
Arthritis causes disability due to pain and inflammation in joints. There are many forms of arthritis, one of which is osteoarthritis whose prevalence increases with age. It occurs in various joints including hip, knee and hand with knee osteoarthritis being more prevalent. There is no cure for it. The management strategies include exercise, glucosamine plus chondroitin sulfate and NSAIDs. In vitro and animal studies provide a rationale for the use of antioxidant supplements for its management. This review assesses the reality of the benefits of antioxidant supplements in the management of knee osteoarthritis. Several difficulties were encountered in examining this issue: poorly conducted studies, a lack of uniformity in disease definition and diagnosis, and muddling of conclusions from attempts to isolate the efficacious molecules. The antioxidant supplements with most evidence for benefit for pain relief and function in knee osteoarthritis were based on curcumin and avocado-soya bean unsaponifiables. Boswellia and some herbs used in Ayurvedic and Chinese medicine may also be useful. The benefits of cuisines with the appropriate antioxidants should be assessed because they may be more economical and easier to incorporate into the lifestyle.
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Affiliation(s)
- Ashok Kumar Grover
- Department of Medicine, HSC 4N41, McMaster University, 1280 Main Street W., Hamilton, ON, L8S 4K1, Canada.
| | - Sue E Samson
- Department of Medicine, HSC 4N41, McMaster University, 1280 Main Street W., Hamilton, ON, L8S 4K1, Canada
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Crespi BJ, Go MC. Diametrical diseases reflect evolutionary-genetic tradeoffs: Evidence from psychiatry, neurology, rheumatology, oncology and immunology. Evol Med Public Health 2015; 2015:216-53. [PMID: 26354001 PMCID: PMC4600345 DOI: 10.1093/emph/eov021] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/17/2015] [Indexed: 12/21/2022] Open
Abstract
Tradeoffs centrally mediate the expression of human adaptations. We propose that tradeoffs also influence the prevalence and forms of human maladaptation manifest in disease. By this logic, increased risk for one set of diseases commonly engenders decreased risk for another, diametric, set of diseases. We describe evidence for such diametric sets of diseases from epidemiological, genetic and molecular studies in four clinical domains: (i) psychiatry (autism vs psychotic-affective conditions), (ii) rheumatology (osteoarthritis vs osteoporosis), (iii) oncology and neurology (cancer vs neurodegenerative disorders) and (iv) immunology (autoimmunity vs infectious disease). Diametric disorders are important to recognize because genotypes or environmental factors that increase risk for one set of disorders protect from opposite disorders, thereby providing novel and direct insights into disease causes, prevention and therapy. Ascertaining the mechanisms that underlie disease-related tradeoffs should also indicate means of circumventing or alleviating them, and thus reducing the incidence and impacts of human disease in a more general way.
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Affiliation(s)
| | - Matthew C Go
- Department of Biological Sciences; Department of Archaeology, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada V5A 1S6 Present address: Department of Anthropology, University of Illinois at Urbana-Champaign, 109 Davenport Hall, 607 S Mathews Avenue, Urbana, IL 61801, USA
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More than just a bump: cam-type femoroacetabular impingement and the evolution of the femoral neck. Hip Int 2011; 21:1-8. [PMID: 21279972 DOI: 10.5301/hip.2011.6288] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/27/2010] [Indexed: 02/04/2023]
Abstract
Recent orthopaedic literature has implicated femoroacetabular impingement, the pathologic abutment of structural aberrancies in the proximal femur and acetabular rim, as an important cause of groin pain in young individuals and a potential factor in early idiopathic osteoarthritis. The etiology and risk factors for developing cam-type morphology are still unknown. The osseous anatomy of the proximal femur in humans is the culmination of nearly 400 million years of evolution. Coxa recta and coxa rotunda are the two predominant morphologies in modern animals. While the former, characterized by a straight head-neck junction, is often present in cursorial creatures, the latter, [corrected] distinguished by high offset at this junction, is exemplified in most humans. Based on the ontology and phylogeny of the proximal femur, coxa rotunda probably developed from a more primitive coxa recta. We believe that cam-type morphology is neither a redevelopment of coxa recta nor a malformation such as slipped capital epiphysis. The aspherical osteocartilaginous bump is associated with an extended physis and has been noted to appear during mid-adolescence. While this protuberance may contribute to future pathology, the authors feel that increased loading of the hip, not impingement activities, during late childhood and early adolescence predispose patients to develop this morphology.
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Commentary 8. J Bodyw Mov Ther 2003. [DOI: 10.1016/s1360-8592(02)00121-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Stamm TA, Machold KP, Smolen JS, Fischer S, Redlich K, Graninger W, Ebner W, Erlacher L. Joint protection and home hand exercises improve hand function in patients with hand osteoarthritis: a randomized controlled trial. ARTHRITIS AND RHEUMATISM 2002; 47:44-9. [PMID: 11932877 DOI: 10.1002/art1.10246] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To determine the effect of joint protection and home exercises on hand function of patients with hand osteoarthritis (OA). METHODS Randomized, controlled, 3-month trial with a blinded assessor. Primary outcome parameter was grip strength; secondary parameters were Health Assessment Questionnaire and visual analog scales (VAS) for pain and global hand function. Forty patients with hand OA were randomly assigned to 2 groups: One group received instruction for joint protection and home hand exercises (JPE group), the control group received an information session about hand OA. RESULTS Grip strength improved by 25% in the JPE group (right hand, P < 0.0001; left hand, P = 0.0005), but not in the control group. Global hand function (by VAS) improved in a larger proportion (65%) of patients in the JPE group (P < 0.05). CONCLUSIONS Joint protection and hand home exercises, easily administered and readily acceptable interventions, were found to increase grip strength and global hand function.
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Abstract
An atavism is the "..reappearance of a lost character (morphology or behaviour) typical of remote ancestors and not seen in the parents or recent ancestors of the organisms displaying the atavistic character" (Hall, 1984). In humans, hypertrichosis (extensive body hair), the presence of a tail and supernumerary nipples are often quoted as examples (Hall, 1995). However, Louis Bolk (1866-1930) explained these phenomena in another way. He considered human morphology as an unspecialized expression of the mammalian developmental pattern. The latter also encompasses potentialities for unilateral or propulsive development pathways (specializations) that usually remain latent in humans, but can become expressed in other species. According to Bolk, the appearance of so-called atavisms in human results from the occasional expression of these latencies in Homo sapiens; they do not recapitulate ancestral conditions.
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