The frequency and presentation of upper thoracic spinous process deviations, their relationship to articular morphology, and the potential influence on static palpation techniques.

BACKGROUND: Static palpation of vertebral spinous process deviations from the midline are often utilized by manual therapists as a means to determine area for treatment of manipulable lesions. Previous research has discussed the diagnostic validity of this technique, but no correlation to vertebral morphology has been presented. AIM: To evaluate the frequency and presentation of vertebral spinous process deviations and their relationship with articular morphology, and the impact this may have in terms of static palpation techniques in the upper thoracic spine. SETTING: This study was conducted on human T1-T6 vertebrae. METHOD: A skeletal sample consisting of 58 humans T1-T6 vertebrae were photographed and linear and angular measurements taken utilizing ImageJ software and non-metric visual observations. RESULTS: Spinous process deviations in the entire sample group (n = 348) were found to occur in a frequency ranging from 19% (n = 11) at T1 to 41.4% (n = 24) at T3. However, when evaluated in terms of frequency within an individual's T1-T6, 83.3% (n = 25) of males and 67.86% (n = 19) of females demonstrated this feature, with an overall incidence of 77.59% (n = 45). Age of individuals did not show an increase in frequency, and no clear pattern could be identified regarding metric measurements and its presence. CONCLUSION: Spinous process deviations in the upper thoracic spine are most probably the result of random normal variations between individuals and are more frequent in males. Static palpation without pain criteria is not a reliable diagnostic technique to determine areas needing manual treatment, as these may be considered normal osseous anatomical variations.

Hominin fossils from Kromdraai and Drimolen inform Paranthropus robustus craniofacial ontogeny.

Ontogeny provides critical information about the evolutionary history of early hominin adult morphology. We describe fossils from the southern African sites of Kromdraai and Drimolen that provide insights into early craniofacial development in the Pleistocene robust australopith Paranthropus robustus. We show that while most distinctive robust craniofacial features appear relatively late in ontogeny, a few do not. We also find unexpected evidence of independence in the growth of the premaxillary and maxillary regions. Differential growth results in a proportionately larger and more postero-inferiorly rotated cerebral fossa in P. robustus infants than in the developmentally older Australopithecus africanus juvenile from Taung. The accumulated evidence from these fossils suggests that the iconic SK 54 juvenile calvaria is more likely early Homo than Paranthropus. It is also consistent with the hypothesis that P. robustus is more closely related to Homo than to A. africanus.

Assessing the need for a standardised paediatric assessment tool for podiatrists in South Africa.

There is no literature to support the existence of an effective standardised assessment tool in South Africa that aids the podiatrist in the early diagnosis of developmental delay in the paediatric patient from age one to five. Podiatrists in South Africa (SA) need a suitable assessment tool to evaluate child development. A potential proforma that could be used by South African podiatrists is the Gait and Lower Limb Observation Proforma (GALLOP) Assessment Tool. AIM: The aim of this research was to evaluate the "ease of use" and "usefulness" of the GALLOP Assessment Tool for podiatrists to effectively assess the paediatric patient from age one to age five. METHODS: The study was of a mixed methods descriptive design type, targeting all Health Professions Council of South Africa (HPCSA) registered podiatrists in the Johannesburg Metropolitan Municipal area. After allowing the participants to use the GALLOP Assessment Tool for a period of time, a survey was conducted to establish the "ease of use" and "usefulness" of the GALLOP Assessment Tool. RESULTS: All participants agreed that the GALLOP Assessment Tool would be beneficial to South African podiatrists and that the assessment tool does not need to be improved upon.

Revisiting mandibular symphyseal shape in juvenile early hominins and modern humans using a deformation-based approach.

The juvenile mandible is important in the investigation of ontogenetic and evolutionary changes among early hominins. We revisit the mandibular symphysis in juvenile specimens of Australopithecus africanus and Paranthropus robustus with two main contributions. First, we employ, for the first time, methods of computational anatomy to model complex symphyseal shape differences. Second, we present new fossil evidence from Kromdraai to improve our knowledge of symphyseal morphology. We describe differences between shapes by landmark-free diffeomorphism needed to align them. We assess which features of the mandibular symphysis best discriminate the juvenile symphysis in these fossil species, relative to the intraspecific variation observed among modern humans. Our approach eliminates potential methodological inconsistencies with traditional approaches (i.e., the need for homologous anatomical landmarks, assumption of linearity). By enabling detailed comparisons of complex shapes in juvenile mandibles, our proposed approach offers new perspectives for more detailed comparisons among Australopithecus, Paranthropus and early Homo.

Frontal sinuses and human evolution.

The frontal sinuses are cavities inside the frontal bone located at the junction between the face and the cranial vault and close to the brain. Despite a long history of study, understanding of their origin and variation through evolution is limited. This work compares most hominin species' holotypes and other key individuals with extant hominids. It provides a unique and valuable perspective of the variation in sinuses position, shape, and dimensions based on a simple and reproducible methodology. We also observed a covariation between the size and shape of the sinuses and the underlying frontal lobes in hominin species from at least the appearance of Homo erectus. Our results additionally undermine hypotheses stating that hominin frontal sinuses were directly affected by biomechanical constraints resulting from either chewing or adaptation to climate. Last, we demonstrate their substantial potential for discussions of the evolutionary relationships between hominin species.

Dental data challenge the ubiquitous presence of Homo in the Cradle of Humankind.

The origins of Homo, as well as the diversity and biogeographic distribution of early Homo species, remain critical outstanding issues in paleoanthropology. Debates about the recognition of early Homo, first appearance dates, and taxonomic diversity within Homo are particularly important for determining the role that southern African taxa may have played in the origins of the genus. The correct identification of Homo remains also has implications for reconstructing phylogenetic relationships between species of Australopithecus and Paranthropus, and the links between early Homo species and Homo erectus. We use microcomputed tomography and landmark-free deformation-based three-dimensional geometric morphometrics to extract taxonomically informative data from the internal structure of postcanine teeth attributed to Early Pleistocene Homo in the southern African hominin-bearing sites of Sterkfontein, Swartkrans, Drimolen, and Kromdraai B. Our results indicate that, from our sample of 23 specimens, only 4 are unambiguously attributed to Homo, 3 of them coming from Swartkrans member 1 (SK 27, SK 847, and SKX 21204) and 1 from Sterkfontein (Sts 9). Three other specimens from Sterkfontein (StW 80 and 81, SE 1508, and StW 669) approximate the Homo condition in terms of overall enamel-dentine junction shape, but retain Australopithecus-like dental traits, and their generic status remains unclear. The other specimens, including SK 15, present a dominant australopith dental signature. In light of these results, previous dietary and ecological interpretations can be reevaluated, showing that the geochemical signal of one tooth from Kromdraai (KB 5223) and two from Swartkrans (SK 96 and SKX 268) is consistent with that of australopiths.

A new early hominin calcaneus from Kromdraai (South Africa).

The Kromdraai site in South Africa has yielded numerous early hominin fossils since 1938. As a part of recent excavations within Unit P, a largely complete early hominin calcaneus (KW 6302) was discovered. Due to its role in locomotion, the calcaneus has the potential to reveal important form/function relationships. Here, we describe KW 6302 and analyze its preserved morphology relative to human and nonhuman ape calcanei, as well as calcanei attributed to Australopithecus afarensis, Australopithecus africanus, Australopithecus sediba, Homo naledi, and the Omo calcaneus (either Paranthropus or early Homo). KW 6302 calcaneal morphology is assessed using numerous quantitative metrics including linear measures, calcaneal robusticity index, relative lateral plantar process position, Achilles tendon length reconstruction, and a three-dimensional geometric morphometric sliding semilandmark analysis. KW 6302 exhibits an overall calcaneal morphology that is intermediate between humans and nonhuman apes, although closer to modern humans. KW 6302 possesses many traits that indicate it was likely well-adapted for terrestrial bipedal locomotion, including a relatively flat posterior talar facet and a large lateral plantar process that is similarly positioned to modern humans. It also retains traits that indicate that climbing may have remained a part of its locomotor repertoire, such as a relatively gracile tuber and a large peroneal trochlea. Specimens from Kromdraai have been attributed to either Paranthropus robustus or early Homo; however, there are no definitively attributed calcanei for either genus, making it difficult to taxonomically assign this specimen. KW 6302 and the Omo calcaneus, however, fall outside the range of expected variation for an extant genus, indicating that if the Omo calcaneus was Paranthropus, then KW 6302 would likely be attributed to early Homo (or vice versa).

Cochlear morphology of Indonesian Homo erectus from Sangiran.

Homo erectus s.l. is key for deciphering the origin and subsequent evolution of genus Homo. However, the characterization of this species is hindered by the existence of multiple variants in both mainland and insular Asia, as a result of divergent chronogeographical evolutionary trends, genetic isolation, and interbreeding with other human species. Previous research has shown that cochlear morphology embeds taxonomic and phylogenetic information that may help infer the phylogenetic relationships among hominin species. Here we describe the cochlear morphology of two Indonesian H. erectus individuals (Sangiran 2 and 4), and compare it with a sample of australopiths, Middle to Late Pleistocene humans, and extant humans by means of linear measurements and both principal components and canonical variates analyses performed on shape ratios. Our results indicate that H. erectus displays a mosaic morphology that combines plesiomorphic (australopithlike) features (such as a chimplike round cochlear cross section and low cochlear thickness), with derived characters of later humans (a voluminous and long cochlea, possibly related to hearing abilities)-consistent with the more basal position of H. erectus. Our results also denote substantial variation between the two studied individuals, particularly in the length and radius of the first turn, as well as cross-sectional shape. Given the small size of the available sample, it is not possible to discern whether such differences merely reflect intraspecific variation among roughly coeval H. erectus individuals or whether they might result from greater age differences between them than currently considered. However, our results demonstrate that most characters found in later humans were already present in Indonesian H. erectus, with the exception of Neanderthals, which display an autapomorphic condition relative to other Homo species.

The Thorny Issue of African Porcupines: a New Mandible of Hystrix makapanensis from Olduvai Gorge (Tanzania) and Rediagnosis of the Species.

Several porcupine taxa are reported from the middle Miocene to the early Holocene in the Old World. Among these, five species of the subfamily Hystricinae occurred in Africa approximately in the last 6 Ma: the extinct Hystrix makapanensis, Hystrix leakeyi, and Xenohystrix crassidens and the still living Hystrix africaeaustralis and Hystrix cristata. The large-sized H. makapanensis is reported from numerous sites in East and South Africa between the early Pliocene and Early Pleistocene. In this paper, we describe a new mandible of H. makapanensis from the world-renowned Tanzanian paleontological and archeological site of Olduvai Gorge (HWK West; lowermost Bed II; ca. 1.8-1.7 Ma). The discovery of the new mandible triggered a comprehensive review of the entire African record of H. makapanensis. In particular, we describe or re-analyze the samples from South Africa (Makapansgat Limeworks, Gondolin, Kromdraai, Swartkrans, and Sterkfontein), Tanzania (Olduvai and Laetoli), Ethiopia (Omo Shungura and Hadar), and Kenya (Chemeron), enriching the quantity of specimens confidently referable to this species and above all improving the information on its craniodental anatomy. On this basis, we: (1) propose an emended diagnosis of H. makapanensis; (2) point out the morphological and biometric differences between H. makapanensis and other African Hystricinae (also in terms of body mass); and (3) broaden the knowledge on the geographical and chronological distribution of this extinct species. Supplementary Information: The online version contains supplementary material available at 10.1007/s10914-021-09588-z.

Trabecular bone properties in the ilium of the Middle Paleolithic/Middle Stone Age Border Cave 3 Homo sapiens infant and the onset of independent gait.

The Border Cave 3 (BC3) infant skeleton has been understudied, despite its importance as an example of a well-preserved and fairly complete immature skeleton of early Homo sapiens which potentially provides a rare window into various aspects of ontogenetic development, including locomotor activity (e.g., timing of gait events). Trabecular structure in the BC3 ilium was evaluated to investigate whether it matches that of an equivalently aged infant from a postindustrialized society. Microcomputed tomography (µCT) scans were acquired from the BC3 infant and from an ontogenetic series of 25 postindustrial infants that were divided into three age classes (ACs) ranging from neonates to toddlers (<36 months). All ilia were qualitatively compared and then digitally subdivided into 10 volumes of interest (VOIs) based on anatomical reference points. The VOIs were quantified and ontogenetic differences in trabecular structure were statistically evaluated. Across the comparative ontogenetic series, trabecular architectural properties overlapped in all regions. However, trabecular thickness increased significantly after the first year of life. The BC3 infant demonstrated generally similar trabecular structure to that observed in the age-equivalent postindustrial infants (AC2), including relatively strong development of the trabecular chiasma qualitatively. However, some interesting distinctions were observed in BC3, such as low strut thickness compared with infants from the postindustrial sample, that bear further exploration in future studies. Evaluation of only one individual from the Middle Stone Age (MSA), coupled with the relatively small comparative sample, limit our ability to distinguish more meaningful biological differences in trabecular structure throughout ontogeny from idiosyncratic characteristics. Nonetheless, results of this study extend ongoing research on infant locomotor and morphological development to archeological populations in the Middle Stone Age. Further cross-cultural studies consisting of larger comparative postindustrial samples may provide additional information on trabecular structure in the infant ilium during this important developmental timeframe.

Cerebral blood flow rates in recent great apes are greater than in Australopithecus species that had equal or larger brains.

Brain metabolic rate (MR) is linked mainly to the cost of synaptic activity, so may be a better correlate of cognitive ability than brain size alone. Among primates, the sizes of arterial foramina in recent and fossil skulls can be used to evaluate brain blood flow rate, which is proportional to brain MR. We use this approach to calculate flow rate in the internal carotid arteries (Q˙ICA), which supply most of the primate cerebrum. Q˙ICA is up to two times higher in recent gorillas, chimpanzees and orangutans compared with 3-million-year-old australopithecine human relatives, which had equal or larger brains. The scaling relationships between Q˙ICA and brain volume (Vbr) show exponents of 1.03 across 44 species of living haplorhine primates and 1.41 across 12 species of fossil hominins. Thus, the evolutionary trajectory for brain perfusion is much steeper among ancestral hominins than would be predicted from living primates. Between 4.4-million-year-old Ardipithecus and Homo sapiens, Vbr increased 4.7-fold, but Q˙ICA increased 9.3-fold, indicating an approximate doubling of metabolic intensity of brain tissue. By contrast, Q˙ICA is proportional to Vbr among haplorhine primates, suggesting a constant volume-specific brain MR.

Flexion location of the first metatarsophalangeal joint and the location of forefoot bend in general purpose women's footwear.

BACKGROUND: General purpose footwear could have a built-in flexion location which may not match the anatomical fulcrum location for an individual's foot. Mismatched fulcra impact on joint function, and may delay healing of an injured first metatarsophalangeal joint (first MP joint). This study compared the location of the first MP joint in an asymptomatic sample of the South African female population to the bend location set within the lasts (used by footwear manufacturers) to find whether mismatches of the flexion locations of the joint to the bending location of the footwear were likely. METHODS: The study used a three dimensional foot measurement database of 453 female participants to find the fulcrum location of the first MP joint. The distance between the heel and the first MP joint was expressed as a percentage of the overall length of the unshod foot. Similar measures for sandals and closed shoes were derived, and all were compared to manufacturer last data. RESULTS: The location of first MP joint ranged from 70% to 79% of total foot length, significantly different from last design specifications of 63% or 66% (p<0.0001). The range of first MP joint fulcrum locations in the same size feet occurred in a wide 24mm mediolateral band under the forefoot, termed a flexion zone. CONCLUSIONS: The first MP joint cannot properly function as a fulcrum unless footwear has a matching flexion location. Footwear designs should incorporate a wide flexion zone located under the forefoot to permit the range of first MP joint flexion locations. Recommendations to patients are to select appropriate flexible footwear to prevent shear forces, reduce strain, prevent injury and enable range of motion function and healing of injury.

One small step: A review of Plio-Pleistocene hominin foot evolution.

Bipedalism is a hallmark of being human and the human foot is modified to reflect this unique form of locomotion. Leonardo da Vinci is credited with calling the human foot "a masterpiece of engineering and a work of art." However, a scientific approach to human origins has revealed that our feet are products of a long, evolutionary history in which a mobile, grasping organ has been converted into a propulsive structure adapted for the rigors of bipedal locomotion. Reconstructing the evolutionary history of foot anatomy benefits from a fossil record; yet, prior to 1960, the only hominin foot bones recovered were from Neandertals. Even into the 1990s, the human foot fossil record consisted mostly of fragmentary remains. However, in the last two decades, the human foot fossil record has quadrupled, and these new discoveries have fostered fresh new perspectives on how our feet evolved. In this review, we document anatomical differences between extant ape and human foot bones, and comprehensively examine the hominin foot fossil record. Additionally, we take a novel approach and conduct a cladistics analysis on foot fossils (n = 19 taxa; n = 80 characters), and find strong evidence for mosaic evolution of the foot, and a variety of anatomically and functionally distinct foot forms as bipedal locomotion evolved.

Manual therapy interventions in the treatment of plantar fasciitis: A comparison of three approaches.

BACKGROUND: Plantar fasciitis is one of the common causes of heel pain and a common musculoskeletal problem often observed by clinicians. Numerous options are available in treating plantar fasciitis conservatively, but no previous studies have compared combined conservative management protocols. AIM: The aim of this study was to compare manipulation of the foot and ankle and cross friction massage of the plantar fascia; cross friction massage of the plantar fascia and gastrocsoleus complex stretching; and a combination of the aforementioned protocols in the treatment of plantar fasciitis. SETTING: This study was conducted at the University of Johannesburg, Chiropractic Day Clinic, and included participants that complied with relevant inclusion criteria. METHODS: Forty-five participants between the ages of 18 and 50 years with heel pain for more than 3 months were divided into three groups and received one of the proposed treatment interventions. The data collected were range of motion (ROM) of the ankle (using a goniometer) and pain perception using the McGill Pain Questionnaire and Functional foot index and algometer. RESULTS: The results of this study indicate that cross friction massage of the plantar fascia and stretching of the gastrocsoleus complex showed the greatest overall improvement in terms of reducing the pain and disability and ankle dorsiflexion ROM, whereas the combination group showed the greatest increase in plantar flexion. CONCLUSION: The results demonstrated that all three protocols had a positive effect on the ROM and pain perception to patients with plantar fasciitis.

Manual therapy interventions in the treatment of plantar fasciitis: a comparison of three approaches

Background: Plantar fasciitis is one of the common causes of heel pain and a common musculoskeletal problem often observed by clinicians. Numerous options are available in treating plantar fasciitis conservatively, but no previous studies have compared combined conservative management protocols. Aim: The aim of this study was to compare manipulation of the foot and ankle and cross friction massage of the plantar fascia; cross friction massage of the plantar fascia and gastrocsoleus complex stretching; and a combination of the aforementioned protocols in the treatment of plantar fasciitis. Setting: This study was conducted at the University of Johannesburg, Chiropractic Day Clinic, and included participants that complied with relevant inclusion criteria. Methods: Forty-five participants between the ages of 18 and 50 years with heel pain for more than 3 months were divided into three groups and received one of the proposed treatment interventions. The data collected were range of motion (ROM) of the ankle (using a goniometer) and pain perception using the McGill Pain Questionnaire and Functional foot index and algometer. Results: The results of this study indicate that cross friction massage of the plantar fascia and stretching of the gastrocsoleus complex showed the greatest overall improvement in terms of reducing the pain and disability and ankle dorsiflexion ROM, whereas the combination group showed the greatest increase in plantar flexion. Conclusion: The results demonstrated that all three protocols had a positive effect on the ROM and pain perception to patients with plantar fasciitis

The evolution of the human foot.

There are 26 bones in each foot (52 in total), meaning that roughly a quarter of the human skeleton consists of foot bones. Yet, early hominin foot fossils are frustratingly rare, making it quite difficult to reconstruct the evolutionary history of the human foot. Despite the continued paucity of hominid or hominin foot fossils from the late Miocene and early Pliocene, the last decade has witnessed the discovery of an extraordinary number of early hominin foot bones, inviting a reassessment of how the human foot evolved, and providing fresh new evidence for locomotor diversity throughout hominin evolution. Here, we provide a review of our current understanding of the evolutionary history of the hominin foot.

A quantification of calcaneal lateral plantar process position with implications for bipedal locomotion in Australopithecus.

The evolution of bipedalism in the hominin lineage has shaped the posterior human calcaneus into a large, robust structure considered to be adaptive for dissipating peak compressive forces and energy during heel-strike. A unique anatomy thought to contribute to the human calcaneus and its function is the lateral plantar process (LPP). While it has long been known that humans possess a plantarly positioned LPP and apes possess a more dorsally positioned homologous structure, the relative position of the LPP and intraspecific variation of this structure have never been quantified. Here, we present a method for quantifying relative LPP position and find that, while variable, humans have a significantly more plantar position of the LPP than that found in the apes. Among extinct hominins, while the position of the LPP in Australopithecus afarensis falls within the human distribution, the LPP is more dorsally positioned in Australopithecus sediba and barely within the modern human range of variation. Results from a resampling procedure suggest that these differences can reflect either individual variation of a foot structure/function largely shared among Australopithecus species, or functionally distinct morphologies that reflect locomotor diversity in Plio-Pleistocene hominins. An implication of the latter possibility is that calcaneal changes adaptive for heel-striking bipedalism may have evolved independently in two different hominin lineages.

The relationship between the distal metatarsal articular angle and intersesamoidal crista: An osteological study.

BACKGROUND: As hallux valgus (HV) progresses, the first metatarsal drifts medially and the subsequent lateral drift of the sesamoids results in intersesamoidal crista erosion. This study aimed to provide a novel method of assessing crista erosion and determine if there is a relationship between that erosion and an increase in the distal metatarsal articular angle (DMAA). METHODS: The DMAA and size of the intersesamoidal crista was measured on the first metatarsals of 120 adult modern human individuals. There was an equitable spread of both sexes, a wide age range (18-88 years), from three South African population groups (Zulu, Sotho, "European"). The following non-metric features were observed: intersesamoidal crista appearance, metatarsal head shape, and first intermetatarsal facet. Correlation tests, t-tests and Analyses of Variance (ANOVA) were used to determine relationships between variables. RESULTS: The Pearson correlation test showed no significant correlation between the DMAA and crista ratio (r=0.092, p=0.154, α=0.05). DMAA: there was a significant difference between sides (p=0.009), right side larger; there was a significant difference between Zulu and "European" samples (p=0.036) but not between "Europeans" and Sotho (p=0.270); and there was a slight positive correlation with an increase in age. Crista: there was a significant difference between the sexes (p=0.044), with females having less erosion. CONCLUSIONS: There is no significant relationship between the DMAA and crista erosion. Severe cartilaginous erosion is present before osteological changes occur, and the unexpected result may be reflected in skeletal specimens in which no cartilaginous changes can be observed. A novel, experimental method of assessing HV in modern human skeletal material is proposed.