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Journal: Clinical anatomy (New York, N.Y.)

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Human semen contains spermatozoa secreted by the testes and a mixture of components produced by the bulbo-urethral and Littre (paraurethral) glands, prostate, seminal vesicles, ampulla and epididymis. Ejaculation is used as a synonym for the external ejection of semen, but it comprises two phases: emission and expulsion. As semen collects in the prostatic urethra, the rapid preorgasmic distension of the urethral bulb is pathognomonic of impeding orgasm, and the man experiences a sensation that ejaculation is inevitable (in women, emission is the only phase of orgasm). The semen is propelled along the penile urethra mainly by the bulbocavernosus muscle. With Kegel exercises, it is possible to train the perineal muscles. Immediately after the expulsion phase the male enters a refractory period, a recovery time during which further orgasm or ejaculation is physiologically impossible. Age affects the recovery time: as a man grows older, the refractory period increases. Sexual medicine experts consider premature ejaculation only in the case of vaginal intercourse, but vaginal orgasm has no scientific basis, so the duration of intercourse is not important for a woman’s orgasm. The key to female orgasm are the female erectile organs; vaginal orgasm, G-spot, G-spot amplification, clitoral bulbs, clitoris-urethra-vaginal complex, internal clitoris and female ejaculation are terms without scientific basis. Female sexual dysfunctions are popular because they are based on something that does not exist, i.e. the vaginal orgasm. The physiology of ejaculation and orgasm is not impaired in premature ejaculation: it is not a disease, and non-coital sexual acts after male ejaculation can be used to produce orgasm in women. Teenagers and men can understand their sexual responses by masturbation and learn ejaculatory control with the stop-start method and the squeeze technique. Premature ejaculation must not be classified as a male sexual dysfunction. It has become the center of a multimillion dollar business: is premature ejaculation - and female sexual dysfunction - an illness constructed by sexual medicine experts under the influence of drug companies? This article is protected by copyright. All rights reserved.

Concepts: Sexual intercourse, Semen, Prostate, Orgasm, Ejaculation, Penis, Male reproductive system, Masturbation

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The origin of the Papal Benediction Sign has been a source of controversy for many generations of medical students. The question has been whether the Papal Benediction Sign posture is the result of an injury to the median nerve or to the ulnar nerve. The increasingly popular use of online “chat rooms” and the vast quantities of information available on the internet has led to an increasing level of confusion. Looking in major anatomy texts, anatomy and board review books as well as numerous internet sites the answer remains unresolved. Through the analysis of functional anatomy of the hand, cultural and religious practices of the early centuries of the Common Era and church art a clear answer emerges. It will become apparent that this hand posture results from an ulnar neuropathy. Clin. Anat., 2015. © 2015 Wiley Periodicals, Inc.

Concepts: Ulnar nerve, Brachial plexus

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This review, with 21 figures and 1 video, aims to clarify some important aspects of the anatomy and physiology of the female erectile organs (triggers of orgasm), which are important for the prevention of female sexual dysfunction. The clitoris is the homologue of the male’s glans and corpora cavernosa, and erection is reached in three phases: latent, turgid, and rigid. The vestibular bulbs cause “vaginal” orgasmic contractions, through the rhythmic contraction of the bulbocavernosus muscles. Because of the engorgement with blood during sexual arousal, the labia minora become turgid, doubling or tripling in thickness. The corpus spongiosum of the female urethra becomes congested during sexual arousal; therefore, male erection equals erection of the female erectile organs. The correct anatomical term to describe the erectile tissues responsible for female orgasm is the female penis. Vaginal orgasm and the G-spot do not exist. These claims are found in numerous articles that have been written by Addiego F, Whipple B, Jannini E, Buisson O, O'Connell H, Brody S, Ostrzenski A, and others, have no scientific basis. Orgasm is an intense sensation of pleasure achieved by stimulation of erogenous zones. Women do not have a refractory period after each orgasm and can, therefore, experience multiple orgasms. Clitoral sexual response and the female orgasm are not affected by aging. Sexologists should define having sex/love making when orgasm occurs for both partners with or without vaginal intercourse. Clin. Anat., 2012. © 2012 Wiley Periodicals, Inc.

Concepts: Sexual intercourse, Human sexuality, Clitoris, Vagina, Orgasm, Penis, Sexual arousal, Erogenous zone

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Research on the history of anatomy in the Third Reich has often concentrated on the influence of the National Socialist (NS) regime on anatomists and their consequent unethical activities. Only recently, the focus has shifted to NS victims whose bodies were used for anatomical purposes. As a first approach to learning more about the victims, this study investigated the persons whose names Hermann Stieve, chairman of the Anatomical Department at the University of Berlin, had listed after using their bodies for his research. The study draws a group portrait and recounts selected biographies of the 174 women and eight men on the list. Most women were of reproductive age, two-thirds were German and a majority was executed for political reasons. Among the executed were at least two pregnant women. The corrected names, biographical data, and nationalities of all persons on the list are published here. None of them volunteered to be dissected, nor were the anatomists at the time interested in the victims' personal background. Future work will have to focus on the investigation of further biographies so that numbers can be turned back into people. This history is a reminder to modern anatomy that ethical body procurement and the anatomists' caring about the body donor is of the utmost importance in a discipline that introduces students to professional ethics in the medical teaching curriculum. Clin. Anat. 26:3-21, 2013. © 2012 Wiley Periodicals, Inc.

Concepts: Ethics, Anatomy, Human anatomy, Business ethics, History of anatomy, Nazi Germany, Nazism, Nazi Party

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Skeletal maturation is divisible to three main components; the time of appearance of an ossification center, its change in morphology and time of fusion to a primary ossification center. With regard to the knee, the intermediate period between appearance and fusion of the ossification centers extends over a period of greater than 10 years. This study aims to investigate radiographically the age at which morphological changes of the epiphyses at the knee occur in a modern Irish population. Radiographs of 221 subjects (137 males; 84 females) aged 9-19 years were examined. Seven nonmetric indicators of maturity were assessed using criteria modified from the Roche, Wainer, and Thissen method and Pyle and Hoerr’s atlas of the knee. Reference charts are presented which display the timeline for each of the grades of development of the seven indicators. Mean age was found to increase significantly with successive grades of development of each of the seven indicators. A significant difference was noted between males and females at the same grade of development for six of the seven indicators. The narrowest age range reported for a single grade of development was 2.2 years for Grade 2 of development of the tibial tuberosity for males. The information on changing morphology of the epiphyses at the knee in the present study may provide an adjunct to methods used for evaluation of skeletal maturity before surgery for orthopedic disorders or to evaluate skeletal age in clinical scenarios where either delayed or precocious skeletal maturation is suspected. Clin. Anat. 26:755-767, 2013. © 2012 Wiley Periodicals, Inc.

Concepts: Time, Bone, Human, Grade, The Age, Change, Endochondral ossification, Irish language

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The prevalence of sesamoid bones in the hands has been reported in some previous articles. Most of them, however, have reported sesamoid bones of the metacarpophalangeal joint of the hand and of the interphalangeal (IP) joint of the thumb. The present study investigates the prevalence of sesamoid bones of the IP joint of the thumb and fingers. A retrospective review of radiologic views of the IP joints in the thumb or fingers was performed, including a total of 650 patients (1,096 thumbs or fingers). Sesamoid bones were found in the IP joint of the thumb at 67% (212 of 318), while the index, middle, ring, little fingers had sesamoid bones in the proximal interphlangeal (PIP) joint at 0% (0 of 172), 0.4% (1 of 244), 0.5% (1 of 183), and 1% (2 of 179), respectively. None of the four fingers had sesamoid bones in the distal IP joint. Previous articles have described the similar prevalence to the present study, of sesamoid bones of the IP joint of the thumb, while some others reported the different prevalence. About the PIP joint, no previous articles have found a sesamoid bone. Because the lateral X-ray view is more accurate and suitable to evaluate sesamoid bones, we used the lateral one for the present study. The knowledge that sesamoid bones occurs at these rates in the thumb IP joint and finger PIP joints is helpful to differentiate chip fractures from sesamoid bones near the IP joint, including the PIP joint. Clin. Anat., 2012. © 2012 Wiley Periodicals, Inc.

Concepts: Bone, Skeletal system, Joints, Patella, Finger, Hand, Thumb, Sesamoid bone

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Hypertrophy of abductor hallucis muscle is one of the reported causes of compression of tibial nerve branches in foot, resulting in tarsal tunnel syndrome. In this study, we dissected the foot (including the sole) of 120 lower limbs in 60 human cadavers (45 males and 15 females), aged between 45 and 70 years to analyze the possible impact of abductor hallucis muscle in compression neuropathy of tibial nerve branches. We identified five areas in foot, where tibial nerve branches could be compressed by abductor hallucis. Our findings regarding three of these areas were substantiated by clinical evidence from ultrasonography of ankle and sole region, conducted in the affected foot of 120 patients (82 males and 38 females), aged between 42 and 75 years, who were referred for evaluation of pain and/or swelling in medial side of ankle joint with or without associated heel and/or sole pain. We also assessed whether estimation of parameters for the muscle size could identify patients at risk of having nerve compression due to abductor hallucis muscle hypertrophy. The interclass correlation coefficient for dorso-planter thickness of abductor hallucis muscle was 0.84 (95% CI, 0.63-0.92) and that of medio-lateral width was 0.78 (95% CI, 0.62-0.88) in the imaging study, suggesting both are reliable parameters of the muscle size. Receiver operating characteristic curve analysis showed, if ultrasonographic estimation of dorso-plantar thickness is >12.8 mm and medio-lateral width > 30.66 mm in patients with symptoms of nerve compression in foot, abductor hallucis muscle hypertrophy associated compression neuropathy may be suspected. Clin. Anat., 2012. © 2012 Wiley Periodicals, Inc.

Concepts: Foot, Tibial nerve, Human anatomy, Receiver operating characteristic, Ankle, Human leg, Calcaneus, Lateral plantar nerve

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We describe in this paper a rare case of a 45-year-old male with a common stem origin of the left gastric artery (LGA), right inferior phrenic artery (RIPA), and left inferior phrenic artery (LIPA), in association with the presence of a hepatosplenomesenteric trunk (HSMT) arising from the abdominal aorta (AA), as revealed by routine multidetector computed tomography (MDCT) angiography. The common stem origin of the LGA, RIPA, and LIPA had an endoluminal diameter of 3.3 mm, the LGA of 2.8 mm. The endoluminal diameter of the RIPA and LIPA was at the origin of approximately 1 mm, complicating selective chemoembolization of the liver parenchyma. Clin. Anat., 2012. © 2012 Wiley Periodicals, Inc.

Concepts: Stomach, Thoracic diaphragm, Arteries of the abdomen, Left gastric artery, Right gastric artery, Celiac artery, Inferior phrenic arteries, Inferior phrenic vein

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The quadriceps femoris is traditionally described as a muscle group composed of the rectus femoris and the three vasti. However, clinical experience and investigations of anatomical specimens are not consistent with the textbook description. We have found a second tensor-like muscle between the vastus lateralis (VL) and the vastus intermedius (VI), hereafter named the tensor VI (TVI). The aim of this study was to clarify whether this intervening muscle was a variation of the VL or the VI, or a separate head of the extensor apparatus. Twenty-six cadaveric lower limbs were investigated. The architecture of the quadriceps femoris was examined with special attention to innervation and vascularization patterns. All muscle components were traced from origin to insertion and their affiliations were determined. A TVI was found in all dissections. It was supplied by independent muscular and vascular branches of the femoral nerve and lateral circumflex femoral artery. Further distally, the TVI combined with an aponeurosis merging separately into the quadriceps tendon and inserting on the medial aspect of the patella. Four morphological types of TVI were distinguished: Independent-type (11/26), VI-type (6/26), VL-type (5/26), and Common-type (4/26). This study demonstrated that the quadriceps femoris is architecturally different from previous descriptions: there is an additional muscle belly between the VI and VL, which cannot be clearly assigned to the former or the latter. Distal exposure shows that this muscle belly becomes its own aponeurosis, which continues distally as part of the quadriceps tendon. Clin. Anat., 2015. © 2016 Wiley Periodicals, Inc.

Concepts: Muscle, Knee, Nerve, Thigh, Extension, Tendon, Vastus lateralis muscle, Vastus medialis

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Disruption or embryologic derailment of the normal bony architecture of the craniovertebral junction (CVJ) may result in symptoms. As studies of the embryology and pathology of hypoplasia of the occipital condyles and third occipital condyles are lacking in the literature, the present review was performed. Standard search engines were accessed and queried for publications regarding hypoplastic occipital condyles and third occipital condyles. The literature supports the notion that occipital condyle hypoplasia and a third occipital condyle are due to malformation or persistence of the proatlas, respectively. The Pax-1 gene is most likely involved in this process. Clinically, condylar hypoplasia may narrow the foramen magnum and lead to lateral medullary compression. Additionally, this maldevelopment can result in transient vertebral artery compression secondary to posterior subluxation of the occiput. Third occipital condyles have been associated with cervical canal stenosis, hypoplasia of the dens, transverse ligament laxity, and atlanto-axial instability causing acute and chronic spinal cord compression. Treatment goals are focused on craniovertebral stability. A better understanding of the embryology and pathology related to CVJ anomalies is useful to the clinician treating patients presenting with these entities. Clin. Anat., 2013. © 2013 Wiley Periodicals, Inc.

Concepts: Medical terms, Vertebral column, Skull, Normal distribution, Vertebral artery, Occipital bone, Medulla oblongata, Foramen magnum