The anomalous archaic Homo femur from Berg Aukas, Namibia: a biomechanical assessment.

The probably Middle Pleistocene human femur from Berg Aukas, Namibia, when oriented anatomically and analyzed biomechanically, presents an unusual combination of morphological features compared to other Pleistocene Homo femora. Its midshaft diaphyseal shape is similar to most other archaic Homo, but its subtrochanteric shape aligns it most closely with earlier equatorial Homo femora. It has an unusually low neck shaft angle. Its relative femoral head size is matched only by Neandertals with stocky hyperarctic body proportions. Its diaphyseal robusticity is modest for a Neandertal, but reasonable compared to equatorial archaic Homo femora. Its gluteal tuberosity is relatively small. Given its derivation from a warm climatic region, it is best interpreted as having had relatively linear body proportions (affecting proximal diaphyseal proportions, shaft robusticity, and gluteal tuberosity size) combined with an elevated level of lower limb loading during development (affecting femoral head size and neck shaft angle).     

肱骨大结节锁定板与空心螺钉固定治疗肱骨大结节撕脱骨折的疗效比较

目的:比较采用肱骨大结节锁定板与空心螺钉内固定治疗肱骨大结节撕脱骨折的疗效。方法:回顾性分析自2011.01—2017.07诊治的24例肱骨大结节撕脱骨折。根据内固定方式不同分为2组:采用肱骨大结节锁定板治疗14例(A组),采用空心钉治疗10例(B组)。比较分析2组手术时间、术中出血量、平均住院日、切口长度、骨折愈合时间、Constant肩关节功能评分以及术后并发症情况来进行评价。结果:A组(肱骨大结节锁定板)的术中出血量大于B组(空心螺钉),术后3月肩关节功能评分较B组优,最终肩关节功能评分无差异;在住院日、手术时间、切口长度、骨折愈合时间方面,两组没有明显差异。在内固定失效、骨折移位等并发症方面,B组比A组高。结论:对于肱骨大结节骨折,肱骨大结节锁定板比空心螺钉更有优势。     

空心钉配合缝线张力带技术治疗移位的肱骨大结节骨折

目的:探讨使用空心钉配合缝线张力带技术治疗移位的肱骨大结节骨折的效果。方法:2008年3月-2010年3月,收治12例肱骨大结节骨折病人,男10例,女2例,年龄21-71岁,平均年龄46.3岁。其中8例摔伤,2例车祸外伤,2例运动中损伤并伴有盂肱关节脱位。受伤至手术时间5小时-1周。X线显示大结节骨折移位大于5mm。大结节骨折块采用空心钉配合5-Ethibond缝线构成的张力带技术进行固定。结果:患者伤口均一期愈合无感染等并发症发生,所有患者均获随访,随访时间9-33个月,平均14个月。X线显示术后2-4个月骨折愈合,平均2.5个月。美国加州大学洛杉矶分校评分标准评分为(33.65±3.83)分;优9例,良2例,可1例,优良率91.7%。结论:采用切开复位空心钉配合缝线张力带技术治疗肱骨大结节骨折疗效满意,功能恢复良好,疼痛缓解明显。     

The effect of the trabecular microstructure on the pullout strength of suture anchors

This study investigates how the microstructural properties of trabecular bone affect suture anchor performance. Seven fresh-frozen humeri were tested for pullout strength with a 5 mm Arthrex Corkscrew in the greater tuberosity, lesser tuberosity, and humeral head. Micro-computed tomography analysis was performed in the three regions of interest directly adjacent to individual pullout experiments. The morphometric properties of bone mineral density (BMD), structural model index (SMI), trabecular thickness (TbTh), trabecular spacing (TbS), trabecular number (TbN), and connectivity density were compared against suture anchor pullout strength. BMD (r=0.64), SMI (r=?0.81), and TbTh (r=0.71) showed linear correlations to the pullout strength of the suture anchor with p-values<0.0001. A predictive model was developed to explain the variances in the individual BMD, SMI, and TbTh correlations. The multi-variant model of pullout strength showed a stronger relationship (r=0.86) compared to the individual experimental results. This study helps confirm BMD is a major influence on the pullout strength of suture anchors, but also illustrates the importance of local microstructure in pullout resistance of suture anchors.     

The safe face lift with bony anatomic landmarks to elevate the SMAS

The risk for facial nerve injury has been reported to be increased with the inclusion of superficial musculoaponeurotic system (SMAS) elevation as compared with a skin-only face lift. The facial nerve courses through the parotid gland. The SMAS is elevated superficial to the parotid gland. However, in elevating the SMAS anterior to the parotid gland, the facial nerve is at risk of injury where its branches emerge from the anterior edge of the parotid gland. The purpose of this study was to identify bony anatomic landmarks to predict the location of the anterior edge of the parotid gland to avoid injury to the facial nerve branches as they exit the parotid gland. The authors dissected 20 cadaver face halves to determine bony landmarks-the masseteric tuberosity and the inferior lateral orbital rim-to predict the location of the anterior parotid edge. Then they measured the anterior edge of the parotid gland in relation to the vector formed between these two bony landmarks. They identified and measured the most anterior portion of the parotid gland in relation to this vector. Then the most posterior aspect of the parotid gland in relation to this vector was measured. In the 20 dissections, the authors found the most anterior portion of the parotid gland to be 2.7 +/- 1.0 mm anterior to the vector from the inferior lateral orbital rim to the masseteric tuberosity. The most posterior part of the anterior edge of the parotid gland in relation to this vector was found to be 1.0 +/- 1.5 mm posterior to this vector. The parotid gland measured an average of 38.8 +/- 3.5 mm in width from the tragus to the anterior parotid edge. In elevating the SMAS with a face lift, the facial nerve branches can be predicted to exit the anterior edge of the parotid gland, which can be located 38.8 mm anterior to the tragus and near the vector from the inferior lateral orbital wall to the masseteric tuberosity.     

Pullout strength of suture anchors: Effect of mechanical properties of trabecular bone

This study investigated the relationships between trabecular microstructure and elastic modulus, compressive strength, and suture anchor pullout strength. Twelve fresh-frozen humeri underwent mechanical testing followed by micro-computed tomography (μCT). Either compression testing of cylindrical bone samples or pullout testing using an Arthrex 5 mm Corkscrew was performed in synthetic sawbone or at specific locations in the humerus such as the greater tuberosity, lesser tuberosity, and humeral head. Synthetic sawbone underwent identical mechanical testing and μCT analysis. Bone volume fraction (BVF), structural model index (SMI), trabecular thickness (TbTh), trabecular spacing (TbSp), trabecular number (TbN), and connectivity density were compared against modulus, compressive strength, and pullout strength in both materials. In cadaveric bone, modulus showed correlations to all of the microstructural properties, while compressive and pullout strength were only correlated to BVF, SMI, and TbSp. The microstructure of synthetic bone differed from cadaveric bone as SMI and TbTh showed little variation across the densities tested. Therefore, SMI and TbTh were the only microstructural properties that did not show correlations to the mechanical properties tested in synthetic bone. This study helps identify key microstructure–property relationships in cadaveric and synthetic bone as well as illustrate the similarities and differences between cadaveric and synthetic bone as biomechanical test materials.     

The first branch of the lateral plantar nerve and heel pain

The course and ramification pattern of the lateral plantar nerve was studied in serial sections from 4 fetal feet and in dissections from 34 adult feet with special reference to the so called first branch. This branch was found in all of the observed fetal and adult specimen. From its originating point the nerve runs immediately distally to the medial process of the calcaneal tuberosity in a lateral direction to the proximal part of the abductor digiti minimi muscle. During its course the FB gives two branches. One of them penetrates sometimes the insertion of the quadratus plantae muscle, whereas in adult feet it always sends fibres to the periosteum around the medial process of the calcaneal tuberosity and the long plantar ligament. The other innervates the flexor digitorum brevis muscle. The site of a possible entrapment is located between the abductor hallucis muscle and the medial head of the quadratus plantae muscle. There is strong indirect evidence that the nerve is of a mixed type consisting of sensory fibres for the calcaneal periosteum and the medial head of the quadratus plantae muscle. There is strong indirect evidence that the nerve is of a mixed type consisting of sensory fibres for the calcaneal periosteum and the long plantar ligament as well as motor fibres for the quadratus plantae, flexor digitorum brevis and abductor digiti minimi muscles, which may explain the characteristic pain complaints of the heel pain syndrome. The occurrence of a stiff fascia perforated by the nerve branch or a bursa around the insertion of the plantar aponeurosis as has been described by several authors and which was put forward as a possible aetiological factor could not be confirmed in our material.     

锁定钢板与空心螺钉治疗肱骨大结节骨折的疗效比较

目的:比较锁定钢板与空心螺钉治疗肱骨大结节骨折的临床疗效及安全性。方法:对2010年1月至2013年1月手术治疗的81例单纯肱骨大结节骨折患者进行回顾性分析,患者均行切开复位内固定,固定方式分别采用锁定钢板与空心螺钉。围手术期观察指标为:手术时间、术中出血量、住院天数等。术后按时间节点随访,至少为术后1年,最终随访时给予X线摄片以观察愈合情况,采用ASES评分、Constant-Murley评分及VAS评分评估肩关节功能及疼痛程度。结果:63例患者获得随访,随访时间1~3年,平均1.9年。钢板组(33例)ASES评分(91.01±4.88)分、Constant-Murley评分(90.21±3.97)分、VAS评分(0.58±0.63)分,满意率为93.94%;螺钉组(30例)ASES评分(80.58±6.72)分、Constant-Murley评分(80.67±7.25)分、VAS评分(1.08±0.68)分,满意率为73.33%,差异均有统计学意义(P0.05)。结论:肱骨近端锁定钢板治疗单纯肱骨大结节骨折固定可靠,安全性较高,肩关节功能恢复好,并发症发生率较低,可获得较为满意的临床效果。     

Binding of Ca2+ to sulfogalactosylceramide and the sequential effects on the lipid dynamics.

Sulfogalactosylceramide (SGC) is a sulfoglycolipid commonly found in epithelial cells and most animal germ cells. Its cellular function in sperm is unknown, although it has been implicated in cation transport in epithelial cells. The purpose of this study was to determine the lipid dynamic effects of Ca2+ binding to SGC. High-pressure Fourier transform infrared spectroscopy was used in this study. Our spectral results showed that Ca2+ bound to the sulfate moiety of SGC. Moreover, Ca2+ binding weakened the hydrogen bonding of the polar head region of SGC and the hydrocarbon chains became more disordered as revealed by an increase in the correlation field splitting pressure of SGC. Consequently, Ca2+ binding to SGC would increase the fluidity of SGC multibilayers. However, the presence of an alpha-hydroxyl group on the SGC fatty acid was found to strengthen the hydrogen bonding of the polar head region and as a consequence reduced the Ca(2+)-enhanced hydrocarbon chain disorder. Experimental approaches, described in this paper, serve as a model for further studies of the effects of Ca2+ binding on the dynamics of membranes containing SGC or other sulfatides.     

Fine needle aspiration in nodular fasciitis of the face

Nodular fasciitis (NF) appears typically as a rapidly growing solitary mass which is most commonly located on the extremities, followed by the trunk and then the head and neck. NF is often suitable for fine needle aspiration (FNA), but few reports of NF diagnosed cytologically have been published. The purpose of this paper is to describe FNA cytology in three cases of nodular fasciitis. All three cases were located on the face.     

Motion analysis of the glenohumeral joint during activities of daily living

The shoulder complex has a larger range of motion (ROM) than any other joint complex in the human body, leaving it prone to numerous injuries. Objective kinematic analysis could yield useful functional insights that may assist clinical practice. Non-invasive optoelectronic motion analysis techniques have been used to assess the shoulders of five healthy subjects performing ROM tasks and 10 functional tasks of daily living. The four most demanding tasks - touching the side and back of the head, brushing the opposite side of the head, lifting an object to shoulder height and lifting an object to head height, required 78%, 60%, 61% and 71%, respectively, of the glenohumeral elevation necessary for full abduction in the scapular plane for the 10 shoulders. This has implications for clinical practice where maximum arm elevation is commonly used to determine a patient's ability to return to work and other everyday activities.     

A comparison of the magnitude and duration of linear and rotational head accelerations generated during hand-, elbow- and shoulder-to-head checks delivered by hockey players

Ice hockey has the highest rates for concussion among team sports in Canada. In elite play, the most common mechanism is impact to the head by an opposing player’s upper limb, with shoulder-to-head impacts accounting for twice as many concussions as elbow- and hand-to-head impacts combined. Improved understanding of the biomechanics of head impacts in hockey may inform approaches to prevention. In this study, we measured the magnitude and duration of linear and rotational head accelerations when hockey players (n = 11; aged 21–25) delivered checks “as hard as comfortable” to the head of an instrumented dummy with their shoulder, elbow and hand. There were differences in both peak magnitude and duration of head accelerations across upper limb impact sites, based on repeated-measures ANOVA (p < 0.005). Peak linear head accelerations averaged 1.9-fold greater for hand and 1.3-fold greater for elbow than shoulder (mean values = 20.35, 14.23 and 10.55 g, respectively). Furthermore, peak rotational head accelerations averaged 2.1-fold greater for hand and 1.8-fold greater for elbow than shoulder (1097.9, 944.1 and 523.1 rad/s², respectively). However, times to peak linear head acceleration (a measure of the duration of the acceleration impulse) were 2.1-fold longer for shoulder than elbow, and 2.5-fold longer for shoulder than hand (12.26, 5.94 and 4.98 ms, respectively), and there were similar trends in the durations of rotational head acceleration. Our results show that, in body checks to the head delivered by varsity-level hockey players, shoulder-to-head impacts generated longer durations but lower magnitude of peak head acceleration than elbow- and hand-to-head impacts.     

Nuclear medicine studies of aging—VII. Humeral deltoid tuberosity on bone scans and radiographs

Because of the occasional finding of increased deposition of bone imaging agent in the area of the humeral deltoid tuberosity, we analyzed both bone scans and radiographs to determine if there were age related correlations. Only 29% of patients of age 35 years or younger showed any radiographie evidence of deltoid tuberosity. This increased to 48% in the 36–64 y age group (and 46% in those of age 65 y and above). Bone scans (^99mTc-MDP) of the humerus showed that 26% of individuals of ages 20–39 y had increased uptake in the deltoid tuberosity area. The figure was 21% of those in the 85–94 y age group. However, distribution between sexes in the 20–39 y age cohort was asymmetric (44% of males showed the bone scan finding, but only 15% of the females). We then reviewed cases that had shown the most prominent deltoid tuberosity on humeral radiographs. Thirteen of the 14 cases (93%) were males. Deposition of bone imaging agent in the deltoid tuberosity region was thus only slightly correlated with age (more common after age 35 y), but strongly correlated with sex (males more common) in all three major age groups (35 and under, 36–64, and 65 years and over). Possible interrelations with bone size and muscle mass were pointed out.     

Motion analysis of the glenohumeral joint during activities of daily living

The shoulder complex has a larger range of motion (ROM) than any other joint complex in the human body, leaving it prone to numerous injuries. Objective kinematic analysis could yield useful functional insights that may assist clinical practice. Non-invasive optoelectronic motion analysis techniques have been used to assess the shoulders of five healthy subjects performing ROM tasks and 10 functional tasks of daily living. The four most demanding tasks – touching the side and back of the head, brushing the opposite side of the head, lifting an object to shoulder height and lifting an object to head height, required 78%, 60%, 61% and 71%, respectively, of the glenohumeral elevation necessary for full abduction in the scapular plane for the 10 shoulders. This has implications for clinical practice where maximum arm elevation is commonly used to determine a patient's ability to return to work and other everyday activities.     

The long head of the triceps brachii as a free functioning muscle transfer

This anatomic study investigates the possibility of using the long head of the triceps brachii muscle as a free functioning muscle transfer for the upper limb. It has been reported that the long head is not difficult to harvest and that its loss does not create significant donor-site morbidity. The muscle was studied in 23 fresh frozen upper limbs. The long head in all 23 specimens had a constant and proximal vascular pedicle from the profunda brachii artery and vein. The mean pedicle was long (4 cm) and had large-caliber vessels (diameter, 3-mm artery and 4-mm vein). Angiograms were carried out in five specimens and dye perfusion studies in six specimens. A single branch from the radial nerve of at least 7 cm in length innervated the muscle. Muscle architecture was studied in 12 specimens and revealed that the long head of the triceps is better suited for forearm reconstruction than either the gracilis or the latissimus dorsi muscles. The mean physiologic cross-sectional area (8.36 cm(2)) and fiber length (10.8 cm on the superficial surface and 8.2 cm on the deep surface) of the long head match more closely those of the flexor digitorum profundus and the extensor digitorum communis, the muscles most commonly replaced.     

Dynamic simulation of tibial tuberosity realignment: model evaluation

This study was performed to evaluate a dynamic multibody model developed to characterize the influence of tibial tuberosity realignment procedures on patellofemoral motion and loading. Computational models were created to represent four knees previously tested at 40°, 60°, and 80° of flexion with the tibial tuberosity in a lateral, medial and anteromedial positions. The experimentally loaded muscles, major ligaments of the knee, and patellar tendon were represented. A repeated measures ANOVA with post-hoc testing was performed at each flexion angle to compare data between the three positions of the tibial tuberosity. Significant experimental trends for decreased patella flexion due to tuberosity anteriorization and a decrease in the lateral contact force due to tuberosity medialization were reproduced computationally. The dynamic multibody modeling technique will allow simulation of function for symptomatic knees to identify optimal surgical treatment methods based on parameters related to knee pathology and pre-operative kinematics.     

Development of the head and trunk mesoderm in the dogfish,Scyliorhinus torazame: II. Comparison of gene expression between the head mesoderm and somites with reference to the origin of the vertebrate head

The vertebrate mesoderm differs distinctly between the head and trunk, and the evolutionary origin of the head mesoderm remains enigmatic. Although the presence of somite‐like segmentation in the head mesoderm of model animals is generally denied at molecular developmental levels, the appearance of head cavities in elasmobranch embryos has not been explained, and the possibility that they may represent vestigial head somites once present in an amphioxus‐like ancestor has not been ruled out entirely. To examine whether the head cavities in the shark embryo exhibit any molecular signatures reminiscent of trunk somites, we isolated several developmentally key genes, including Pax1, Pax3, Pax7, Pax9, Myf5, Sonic hedgehog, and Patched2, which are involved in myogenic and chondrogenic differentiation in somites, and Pitx2, Tbx1, and Engrailed2, which are related to the patterning of the head mesoderm, from an elasmobranch species, Scyliorhinus torazame. Observation of the expression patterns of these genes revealed that most were expressed in patterns that resembled those found in amniote embryos. In addition, the head cavities did not exhibit an overt similarity to somites; that is, the similarity was no greater than that of the unsegmented head mesoderm in other vertebrates. Moreover, the shark head mesoderm showed an amniote‐like somatic/visceral distinction according to the expression of Pitx2, Tbx1, and Engrailed2. We conclude that the head cavities do not represent a manifestation of ancestral head somites; rather, they are more likely to represent a derived trait obtained in the lineage of gnathostomes.     

Functional aspects of primate pelvic structure: A multivariate approach

This study aims to clarify the relationship of primate bony pelvic structure to locomotor habit. As with most of the postcranial skeleton, the pelvic bones of species within the Ceboidea and the Cercopithecoidea are remarkably similar visually except for variations in size. Yet there are substantial differences in locomotor pattern between the species in these taxa. I performed canonical analyses on a sample of 17 pelvic variables describing 22 primate species of the Ceboidea, the Cercopithecoidea, and the Hominoidea to discover which variables were significant in separating them into groups. In both analyses there was good separation of major taxa and additional separation of groups that differed in locomotor habit. The separation of colobine from cercopithecine monkeys was particularly consistent. In the analysis, including all 22 species, the variables given particular weight by the canonical analysis were the same as those traditionally used by anatomists for the same purpose. Specifically, breadth of the ischial tuberosity (reflecting presence or absence of ischial callosities) separated the Old from the New World monkeys. Breadth of the iliac tuberosity, in which man and to some extent other hominoids differ from other primates, and ilium height, in which man differs from other primates, were significant. Sagittal diameter of the pelvis was also substantially weighted. Having established that the technique would select variables of anatomical significance, the same method was applied to a study of monkeys only where the characteristics that differ between groups are not well established. Breadth of the ischial tuberosity was again important in separating the Ceboidea from the Cercopithecoidea. Discrimination of locomotor groups within these large divisions was brought about mainly by ischial length and the sagittal diameter of the pelvis. In studying these variables and their relationship to size in greater detail, it was found that among cercopithecoid monkeys, the colobines showed relatively lower values than did cercopithecines for both these dimensions. Atelines showed low values for ischial length but high values for the sagittal pelvic diameter. Biomechanical explanations of these observations are suggested.     

上颌结节在不同年龄阶段发育特征的对照研究

目的:对上颌结节在不同年龄阶段的发育进行研究,并进行组间比较,得出上颌结节的发育特征。方法:全部病例均采用同一台牙科X线机拍摄全口曲面断层片,拍摄条件选择1.1倍恒定放大率模式。根据纳入标准选择病例样本180例,按年龄分为6个实验组,各实验组再按性别分组,对比组间各测量指标的差异。结果:男、女性别组均在M1、M2、M3、L4、L5、L7、L8、L10、L11等测量指标中存在显著性差异。结论:上颌结节的发育并不是随着年龄的增长而平稳增长的,其发育存在高峰期,即10-11岁年龄段,在此年龄段上颌结节在垂直和水平距离上都有快速的发育。而其因素主要来自于上颌第二、第三磨牙的牙冠和牙根发育,其次来自于骨骼的净增长。