Sex determination using scapular and clavicular parameters in modern Thai population / Determinación del sexo utilizando parámetros escapulares y claviculares en la población tailandesa moderna

SUMMARY: As natural disasters or crimes, precise postmortem identification is needed especially in case of unknown human remains. The aim of the study is to assess sexual dimorphism by formulating new multivariate equations based on scapular and clavicular parameters for a modern Thai population. Eight left scapular and six left clavicular parameters were measured from 278 individuals (124 males and 124 females for training group; and 15 males and 15 females for test group) of a modern Thai population with age ranges from 19 to 101 years. All scapular and clavicular parameters were sexually dimorphic. Direct and stepwise multivariate discriminant function analysis was performed to generate models. Three direct multivariate discriminant functions showed accuracy rates from 91.1c to 92.3 % (cross-validated range from 90.3 % to 91.5 %). Similarly, three stepwise multivariate discriminant functions showed accuracy rates from 90.7 % to 92.7 % (cross-validated range from 90.7 % to 92.7 %). Moreover, the test group showed 86.67 % to 100 % of sex determination accuracy in six discriminant functions. As recommendation for sex determination by using combination of the scapular and clavicular parameters yields statistically high accuracy for sex determination. Therefore, the accuracies of these multivariate discriminant function equations obtained from scapula and clavicle can be applied for forensic sex determination, especially in modern Thais.

RESUMEN: En casos de desastres naturales o crímenes se requiere una identificación post mortem precisa, especialmente en el caso de restos humanos desconocidos. El objetivo de este estudio fue evaluar el dimorfismo sexual mediante nuevas ecuaciones multivariadas basadas en parámetros escapulares y claviculares para una población tailandesa moderna. Se midieron ocho parámetros escapulares izquierdos y seis claviculares izquierdos de 278 individuos (124 hombres y 124 mujeres para el grupo de entrenamiento; y 15 hombres y 15 mujeres para el grupo de prueba) de una población tailandesa moderna con rangos de edad de 19 a 101 años. Todos los parámetros escapulares y claviculares presentaban dimorfismo sexual. Se realizaron análisis de funciones discriminantes multivariadas directas paso a paso para generar modelos. Tres funciones discriminantes multivariadas directas mostraron tasas de precisión de 91,1 % a 92,3 % (rango de validación cruzada de 90,3 % a 91,5 %). De manera similar, tres funciones discriminantes multivariadas mostraron tasas de precisión de 90,7 % a 92,7 % (rango de validación cruzada de 90,7 % a 92,7 %). Además, el grupo de prueba mostró del 86,67 % al 100 % de precisión en la determinación del sexo en seis funciones discriminantes. Como recomendación para la determinación del sexo mediante el uso de la combinación de los parámetros escapulares y claviculares, se obtiene una precisión estadísticamente alta para la determinación del sexo. Por lo tanto, las precisiones de estas ecuaciones de funciones discriminantes multivariadas obtenidas de la escápula y la clavícula se pueden aplicar para la determinación forense del sexo, especialmente en los tailandeses modernos.

Anatomic position of the asterion and implication for neurosurgical procedure / Posición anatómica del asterion y sus implicancias en el procedimiento neuroquirúrgico

SUMMARY: The asterion is the joining of the lambdoid, parietomastoid, and occipitomastoid sutures. It is classified into two types, type I shows small bones or woven bones, while in type II, woven bones are non-existent. In this study, forty cadavers were conducted and observed the asterion on both sides of skulls showing the approximate ratio of type II and type I was 3:2. The asterion was located by measuring the distances from the asterion to skull landmarks, including inion, the root of zygoma, and mastoid tip. The mean distance between asterion and inion was 62.9 ? 6.0 mm. The mean distance between asterion and the root of zygomatic arch was 58.3 ? 6.1 mm, whereas the mean distance between asterion and mastoid tip was 51.1 ? 5.3 mm. The most common location related to the asterion was the dural venous sinuses on 65 % of tested sides, followed by infratentorial dura and supratentorial dura (25 % and 10 %, respectively). However, the authors found no differences between sexes, sides, and types in any underlying structures.

RESUMEN: El asterion es la unión de las suturas lambdoidea, parietomastoidea y occipitomastoidea. Clasificado en dos tipos, el tipo I muestra huesos pequeños o hueso laminar, mientras que en el tipo II, el hueso laminar es inexistente. En este trabajo se estudiaron 40 cadáveres y se observó el asterion en ambos lados de los cráneos correspondientes, mostrando una proporción aproximada de tipo II y tipo I de 3:2. El asterion se localizó midiendo las distancias asociadas a puntos de referencia del cráneo: el inion, la raíz del arco cigomático y el ápice del proceso mastoides. La distancia media entre el asterion y el inion fue de 62,9 ? 6,0 mm. La distancia media entre el asterion y la raíz del arco cigomático fue de 58,3 ? 6,1 mm, mientras que la distancia media entre el asterion y el ápice del proceso mastoides fue de 51,1 ? 5,3 mm. La localización más común relacionada con el asterion fueron los senos venosos durales en el 65 % de los lados evaluados, seguido de la duramadre infratentorial y la dura supratentorial (25 % y 10 %, respectivamente). Sin embargo, los autores no encontraron diferencias entre sexo, lados y tipo en ninguna estructura subyacente.

Flow-Cytometric Analysis of HNA-2 Expression and Phenotypes Among Thai Blood Donors

BACKGROUND: Antibodies specific to human neutrophil antigen (HNA), especially HNA-2, are implicated in various conditions, including neonatal alloimmune neutropenia, febrile non-hemolytic transfusion reactions, and transfusion-related acute lung injury. The distribution of the HNA-2 phenotype frequencies in the Thai population remains unknown. This study aimed to investigate HNA-2 phenotype frequencies in Thai blood donors and to compare the relationships of sex and age with HNA-2 expression. METHODS: EDTA blood samples were collected from 220 unrelated healthy Thai blood donors, including 150 males and 70 females, with ages ranging from 20 to 57 years. Polymorphonuclear cells were isolated and stained with monoclonal antibodies clone MEM-166 and clone 2D1, which are specific to human CD177 (HNA-2) and CD45, respectively. HNA-2 expression according to sex and age was analyzed by flow cytometry. RESULTS: Among the 220 donors, HNA-2-positive and HNA-2-null-phenotype frequencies were 0.995 and 0.005, respectively. Mean antigen expression was significantly higher in women (71.01±15.46%) than in men (64.59±18.85%; P < 0.05). No significant differences in HNA-2 expression were found between different age groups. HNA-2 phenotype frequencies were similar to those in Asian, African, American, and Brazilian populations, but were significantly different from those in eastern Japanese, Korean, and French populations (P < 0.001). CONCLUSIONS: This is the first report of HNA-2 phenotype frequencies in a Thai population, and the data will be helpful in predicting the risk of HNA-2 alloimmunization and in recruiting granulocyte panel donors.

Morphometry of Isan-Thai clavicles as a guide for sex determination / Morfometría de las clavículas en una población Isan-Thai como guía para la determinación del sexo

The dried clavicles have been well documented to determine individual sex and age in many races. Such morphometric investigations in Isan (Northeastern) Thais have never been reported. Therefore, this study aimed to estimate the sex from dried clavicles of Isan-Thais using morphometric analysis. The identified 454 dried clavicles (254 males and 200 females), averaged age (60.69±14.36 years) were measured and analyzed for identification point (IP) and the demarking point (DP) values. The results showed that the identified-bone percentages by IP of the maximum clavicular lengths in males and females were 90.55 % (>139.9 mm) and 89 % (<140.6 mm). In addition, such percentages of the mid shaft circumference measured in male clavicles was 83.46 % (>37.7 mm) and in females was 75 % (<37.0 mm). However, percentages of the DP in all parameters were less than 50%. The highest DP values of maximum length of male clavicles was 43.31% (>152.5). In conclusion, the maximum length and mid shaft circumference investigated from this study can be used as basic data of Isan ­ Thais for applying as a guide in forensic sciences for sex determination from dried clavicle remains.

Las clavículas secas han sido bien documentadas en muchas razas para determinar el sexo y la edad individuales. Tales investigaciones morfométricas en Isan (Noreste de Tailandia) nunca han sido reportadas. Por lo tanto, este estudio tuvo como objetivo estimar el sexo de clavículas secas de Isais-Thais utilizando un análisis morfométrico. Se midieron 454 clavículas secas (254 varones y 200 hembras), con una edad media de 60,69 ± 14,36 años, y fueron analizadas para los puntos de identificación (IP) y de demarcación (DP). Los resultados mostraron que los porcentajes de hueso identificados por IP en relación a la longitud clavicular máxima en hombres y mujeres fueron 90,55 % (> 139,9 mm) y 89 % (<140,6 mm), respectivamente. Además, tales porcentajes de circunferencia media del eje, medido en las clavículas de los hombres, fue 83,46 % (> 37,7 mm) y en las de mujeres fue 75 % (<37,0 mm). Sin embargo, los porcentajes de la DP en todos los parámetros fueron menores al 50 %. Los valores más altos de DP de longitud máxima de las clavículas de los hombres fue 43,31 % (> 152,5). En conclusión, la longitud máxima y la circunferencia media del eje investigados a partir de este estudio se pueden utilizar como datos básicos en Isan - Thais para aplicar como guía en las ciencias forenses para la determinación del sexo a partir de restos de clavícula secas.

Antipyretic and anti-inflammatory activities of Thais luteostoma extracts and underlying mechanisms / 中国天然药物

Thais luteostoma has been utilized as a crude drug whose shell and soft tissue have been widely used for the treatment of heat syndrome in China for thousands of years. The present study was designed to investigate the antipyretic and anti-inflammatory activities of T. luteostoma. T. luteostoma was divided into shell (TLSH) and soft tissue (TLST) samples in the present study. The rat model of yeast-induced fever was used to investigate their antipyretic effects; and the rat model of hind paw edema induced by carrageenan was utilized to study their anti-inflammatory activities, and at the same time, the concentration variations of the central neurotransmitter [prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP)], inflammatory mediators [tumor necrosis factor (TNFα), interleukin-1β (IL-1), interleukin-2 (IL-2) and interleukin-6 (IL-6)] and ion (Na(+) and Ca(2+)) were also tested. The results showed that TLSH and TLST extracts significantly inhibited yeast-induced pyrexia in rats (P < 0.05), and exhibited more lasting effects as compared to aspirin, and TLSH had the better antipyretic activity than TLST, and that TLSH and TLST could significantly prevent against carrageenan induced paw edema in rats (P < 0.05); and markedly reduced levels of PGE2, cAMP, TNFα, IL-1β, IL-2, IL-6, and Na(+)/Ca(2+). In fever model, TLST could significantly reduce the levels of PGE2 (P < 0.01) in rats' homogenate and TNFα (P < 0.05), IL-1β (P < 0.01) in the plasma than TLSH, whereas TLSH could reduce the content of IL-2 (P < 0.01) and IL-6 (P < 0.01) in plasma and increase the content of Ca(2+) (P < 0.01) in plasma and homogenate more significantly than TLST. In conclusion, T. luteostoma extract has antipyretic and anti-inflammatory activities, which may be mediated through the suppression of production of PGE2, cAMP, Na(+)/Ca(2+), TNFα, IL-1β, IL-2, and IL-6.

Duffy Blood Group Genotyping in Thai Blood Donors

BACKGROUND: Duffy (FY) blood group genotyping is important in transfusion medicine because Duffy alloantibodies are associated with delayed hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. In this study, FY allele frequencies in Thai blood donors were determined by in-house PCR with sequence-specific primers (PCR-SSP), and the probability of obtaining compatible blood for alloimmunized patients was assessed. METHODS: Five hundred blood samples from Thai blood donors of the National Blood Centre, Thai Red Cross Society, were included. Only 200 samples were tested with anti-Fy(a) and anti-Fy(b) using the gel technique. All 500 samples and four samples from a Guinea family with the Fy(a-b-) phenotype were genotyped by using PCR-SSP. Additionally, the probability of obtaining antigen-negative red blood cells (RBCs) for alloimmunized patients was calculated according to the estimated FY allele frequencies. RESULTS: The FY phenotyping and genotyping results were in 100% concordance. The allele frequencies of FY*A and FY*B in 500 central Thais were 0.962 (962/1,000) and 0.038 (38/1,000), respectively. Although the Fy(a-b-) phenotype was not observed in this study, FY*B(ES)/FY*B(ES) was identified by PCR-SSP in the Guinea family and was confirmed by DNA sequencing. CONCLUSIONS: Our results confirm the high frequency of the FY*A allele in the Thai population, similar to that of Asian populations. At least 500 Thai blood donors are needed to obtain two units of antigen-negative RBCs for the Fy(a-b+) phenotype.

Frequency of FCGR3B Alleles in Thai Blood Donors

BACKGROUND: Human neutrophil antigens (HNAs) are involved in autoimmune and alloimmune neutropenia and transfusion-related acute lung injury. The HNA-1 system is important in immunogenetics, and allele frequencies have been described in different populations. This study investigated the frequency of FCGR3B alleles encoding HNA-1a, HNA-1b, and HNA-1c among Thai blood donors and compared these frequencies with those previously reported for other populations. METHODS: Eight hundred DNA samples obtained from unrelated healthy blood donors at the National Blood Centre, Thai Red Cross Society, Bangkok, and the Blood Bank, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand, were included. Samples were simultaneously typed for each FCGR3B allele using an in-house polymerase chain reaction with sequence-specific primer (PCR-SSP) technique. RESULTS: The frequencies of FCGR3B*1, FCGR3B*2, and FCGR3B*3 alleles in central Thai blood donors were 0.548, 0.452, and 0.004, respectively; only FCGR3B*1 and FCGR3B*2 alleles were found in northern Thai blood donors (0.68 and 0.32, respectively). Compared with other Asian populations, central Thais had higher frequencies of the FCGR3B*2 allele (P<0.001), while the frequencies of the FCGR3B*1 and FCGR3B*2 alleles in northern Thais were similar to those previously reported in Taiwanese and Japanese populations. In contrast, the frequencies of the FCGR3B*1 and FCGR3B*2 alleles in the northern Thai population were statistically different from those observed in central Thai, Korean, German, and Turkish populations. CONCLUSIONS: FCGR3B allele frequencies were significantly different between central and northern Thai blood donors. Our in-house PCR-SSP method is a simple, cost-effective, and convenient method for FCGR3B allele detection.

Cutaneous distributions of genitofemoral and ilioinguinal nerves to pubic, perineal and ventromedial thigh regions in Thais.

Objective: To determine the cutaneous distributions of genitofemoral (Gf) and ilioinguinal (Ig) nerves to pubic, perineal and ventromedial thigh regions in Thais. Methods: The present study was performed bilaterally in 98 halves of 49 embalmed cadavers. The cutaneous distributions of the Gf and/or Ig nerves to these regions were dissected, identified and recorded. Results: Based on the cutaneous distributions of Gf and/or Ig to pubic, perineal, and ventromedial thigh regions, five different types of cutaneous branching patterns of both nerves were identified. Type A (18.28% of cases) had only the branches of Gf to the mons pubis, anteroproximal part of the root of penis, the scrotal or labial and the ventromedial thigh regions but in type B (21.51% of cases) had only the branches of Ig to these regions. The most frequent type of these innervations was type C (39.78% of cases) with dominance of both nerves branching to these regions. In type D (8.60% of cases), having the branches of both nerves but with a dominance of Gf, consisted of 2 subtypes D-1 (2.15% of cases) and D-2 (6.45% of cases). In contrast to type D, type E (11.83% of cases) having the branches of both nerves but with a dominance of Ig, consisted of 2 subtypes E-1 (8.60% of cases) and E-2 (3.23% of cases). Conclusions: These findings would provide the marked anatomic variability of Gf and/or Ig nerves in pubic, perineal and ventromedial thigh regions in Thais, and may assist diagnosis, anesthetic nerve block and prevention nerve damage during surgery.

Anatomic variations of the superficial part of cervical plexus and its branches in Thais.

Objective: To evaluate the variations of superficial part of cervical plexus and its branches in Thais. Methods: We dissected bilaterally in 108 cervical plexuses in Thai cadavers. The anatomic variations of origins and its cutaneous branches of the superficial part of cervical plexus were identified and recorded. Results: The superficial part of cervical plexus derived from the ventral rami of C2, C3, and C4. Its branches consisted of the lesser occipital, great auricular, transverse cervical and supraclavicular nerves. These cutaneous (or superficial) nerves mainly derived from ventral rami of C2-C3 except the supraclavicular nerve from C3-C4. They supplied the skin and superficial structures of the head, neck and shoulder. The anatomic variations of these nerves occurred in both sides. There was no statistical difference with regard to either gender or side. Conclusions: The knowledge of the anatomic variations of cutaneous branches of the superficial cervical plexus from this study could be useful for clinicians in anesthesia blocks, surgical procedures, treatment of pain and abnormalities relating to these cervical nerves.

Anatomic direction of entry for botulinum toxin injection to treat the adductor spasmodic dysphonia in Thais.

Background: Botulinum toxin injections into the thyroarytenoid (TA) muscle of the larynx is the most popular treatment for adductor spasmodic dysphonia. Injection is usually done by percutaneous transcricothyroid membrane with either electromyography (EMG) or fiberoptic laryngoscopy (FOL) to verify placement of the needle within the TA muscle. This procedure requires a working knowledge of three-dimensional anatomy of the larynx to establish the direction for the accurate placement of the needle. Objective: Find out the appropriate angles and depth of the needle for placement of percutaneous transcricothyroid membrane method of botulinum toxin injection by means of studying the larynges of Thai cadavers. Methods: The descriptive study was performed in 45 Thai freshly thawed cadavers. The angle of the needle from midline sagittal plane, the angle in superior relation to tracheal plane, and the depth from midline cricothyroid (CT) membrane to midlength of TA muscle were measured from the two views of photographs, anteroposterior and lateral. Results: The mean angle of 24.2±6.76ο (mean±SD) from the midline sagittal plane in male and 24.9±7.6ο in female were worked out. A mean angle in superior relation to the tracheal plane was 47.7±7.8ο and 51.4±9.6ο in male and female, respectively. The mean depth was 1.7±0.2 and 1.4±0.1 cm in male and female, respectively. Conclusion: The mean angles and depth of the needle insertion from the midline of CT membrane to the center of TA muscle in Thai laryngeal specimens were evaluated. These values were different from the studies in Caucasians, but it could provide a direct relationship to the build of the races. This knowledge may help laryngologists do this procedure more accurately with better outcome, especially in hospitals that have no EMG or FOL guide.

Accuracy of cranial and mandible morphological traits for sex determination in Thais.

Objective: To evaluate the accuracy of sexual dimorphism in the cranium and mandible of Thais using Krogman’s cranioscopy and the modified Krogman’s cranioscopy traits by grading and measurement. Methods: Data were from 101 dry adult skulls (66 males and 35 females) residing in central Thailand. Results: Sex determination using Krogman’s cranioscopy by an inexperienced person had a very high accuracy of 95.5% for males, 82.9% for females respectively and 91.1% overall. According to modified Krogman’s cranioscopy traits by grading, males had larger supraorbital tours, a rougher glabella region and more external occipital protuberance than females. Regarding modified Krogman’s cranioscopy trait by measurement, males had a wider base and a higher mastoid process, with longer and wider occipital condyles than females. Both later methods were also useful in the sexing of fragmented skulls. Conclusion: The cranioscopy study based on 14 traits according to Krogman’s cranioscopy is the best method for sex determination of individual unknown skulls. The modified Krogman’s cranioscopy trait by grading and by measurement is simplified and can very well predict the sexing of fragmented skulls.

Sex determination in Thai skulls by using craniometry: Multiple logistic regression analysis.

Objective: To evaluate sexual dimorphism in the cranium and mandible of Thais by using Jorgensenûs craniometry and to develop a statistical model to determine sex from craniometrical measurements and indices. Methods: One hundred and one Thai skulls (66 males and 35 females) which ranged in age from 18 to 86 years were studied. Results: According to craniometry, the skull of a male is larger and higher than that of a female. Considering each individual measurement, although 26 of 30 measurements and 5 of 14 indices showed a statistically significant difference between males and females, they had some overlaps. To predict gender more accurately, a multiple logistic regression model based on 4 skull measurements (mm) i.e., nasion-basion length (M5), maximum breadth of the cranium (M8), facial length (M40), and bizygomatic breadth of the face (M45) was developed as follows: In (odds) = Z = -52.5312 + 0.27 M5 - 0.1867 M8 + 0.1268 M40 + 0.319 M45 The probability of being males (P) is then ez/(1+ez). Using a cut off point for P of 0.5, this logistic model could correctly predict 82.9% (95% CI: 66.4%, 93.4%) of females and 92.1% (95% CI: 82.4%, 97.4%) of males respectively with the overall accuracy of 88.8% (95% CI: 80.8%, 94.3%). Conclusion: Jorgensenûs craniometry of the cranium and mandible can be used to determine gender among Thais via a multiple logistic regression model on M5, M8, M40 and M45.

The glenoid fossa: Shape, inclination and version in Thais.

A study of the glenoid fossa in Thais was carried out in ninety five normal shoulders in cadavers from the Department of Anatomy, Faculty of Medicine Siriraj Hospital. The mean age of the cadavers at the time of death was 69.8 years. In order to provide basic structural information of the glenoid orientation in adult Thais, the work was done by using a custom-made scapula holder which kept the scapula the scapula in position in which the reference line superimposed with the axis of the scapula. The angular measurement performed by using a goniometer placed contact on both rims of the glenoid and center was superimposed with the reference line. Most of the scapulae, 85%, showed in upward inclination with the value of +6.7o+3.4o (mean + SD) and 13% scapulae tilted downward with -3.7o+1.9o. In a horizontal orientation, 81% of the scapulae faced backward (retroversion) with -5.5o+3.0o and 16% facing forward (anteroversion) with +3.8o+1.6o. The similar figures were also found in the scapula male and female cadavers; 8.5% of male scapulae had an upward inclination with +6.3o+3.3o and 13% a downward inclination with -3.7o+1.9o. Glenoid retroversion was found in 78% of male scapulae (-4.9o+2.7o) and 86% in the female scapulae (-6.1o+3.2o). The glenoid anterversion was found in 20% of male scapulae (+4o+1.5o) and 12% in female scapulae (+3.5o+1.9o). Statistacal analysis between genders and side showed no significant difference, nor a correlation to the dominatarm.

The scapula : Osseous dimensions and gender dimorphism in Thais.

Anatomic and morphometric study of the scapula in Thais was aimed to provide fundamental information for surgical procedures such as fixation device selection, arthrocopic portal placement, prosthetic design and positioning. Therty measurements were carried in 97 scapulas, 25 pairs from female and 23 pairs and one left side from male cadavers. The average age at the time of death was 69.82 years. The average length of scapula measured from the superior angle to the inferior angle was 13.93+1.11 cm. (mean+standard deviation). The thickness of the lateral border taken from the midpoint and 1 cm. from the edge was 0.82+0.20 cm. thicker than the medial border taken in the same manner (0.12+0.08 cm.). The inferior angle was more acute at 40.88+5.29 degrees and thicker than the superior angle (84.29+9.43 degrees). The superior border was thin and sharp; the suprascapular notch was presented on the border medial to the root of the coracoid process. The depth and shape of the suprascapular notch were variable. The length of the spin measured from the tip of the acromion process to its medial edge was 12.89+0.94 cm. The anteroposterior width of the spine measured were 0.60+0.15 and 1.78+0.29 cm. taken from 1 and 4 cm. away from its medial edge, respectively, and 4.15+0.43 cm. width meansured in the plane of the spinoglenoid notch. The dimensions of the acromion of the acromion process were 4.41+0.47 cm. X 2.50+0.37 cm. (L x W x T). The distance between the acromion and coracoid processes was 3.11+0.41 cm. The coracoids measurements were 4.04+0.41 cm. X 1.46+0.19 cm. X 0.74+0.12 cm. (L x W x T). The distance measured from the tip of the coracoid process to the bottom of suprascapular notch was 4.84+0.39 cm. The glenoid dimensions were 3.58+0.35 (superoinferior) and 2.73+0.31 cm. (anteroposterior). The thickness of the scapula neck was 1.91+0.37 and 1.02+0.27 cm. at 1 and 2 cm. away from the glenoid rims. Scapulas from male cadavers were significantly larger than those from female cadavers in 27 meansurements.

Anatomic variations of the sacral plexus in Thais.

The aim of this study was to examine the variation of the sacral plexus in Thais in terms of its origin, branches, and variation in each branch. Anatomical dissections were conducted in 150 halves of formalin-embalmed cadavers. All preserved cadavers were Thais, ranging in age from 35 to 85 years old, 86 males and 64 females. The sacral plexus was markedly comprised of the fourth lumbar to fourth sacral ventral rami (L4-S4) in 98.67% of the plexuses (or 148 cases) except for two plexuses (1.33% of the plexuses) those were derived from the ventral rami of the fourth lumbar to fifth sacral ventral rami (L4-S5). The sacral plexus, lying on the posterior wall of the lesser pelvis to the piriformis muscle, has nine named branches. Six of these are distributed to the buttock and lower lomp, including 1) Nerve to the Quadratus Femoris and Gemellus Inferior, 2) Nerve to the Obturator Internus and Gemellus Inferior, 3) Superior Gluteal, 4) Inferior Gluteal, 5) Posterior Femoral Cutaneous and 6) Sciatic. The other branches supply structures belonging to the pelvis, including 7) Nerve to the Piriformis, 8) Pudendal and 9) Pelvic Splanchnic. The variant of origination and formations of all branches occur on both side. However, the anatomic variability of the plexuses was not statistically different with regard to either side or gender. The results from this study provided additional information and new insights into the sacral plexus in terms of its origins, branches, and variations of each branch that might be useful in medicine, anesthesia, surgery and physical therapy.

Anatomic variations of the lumbar plexus in Thais.

The aim of this study was to examine the variation of the lumbar plexus in Thais in terms of its origin, branches, and variation of each branch. Anatomical dissections were conducted in 150 halves of formalin-embalmed cadavers. All preserved cadavers were Thais, ranging the age from 35 to 85 years old, 86 males and 64 females. The lumbar plexus was markedly composed of the first to fourth lumbar ventral rami (L1-L4) in 81.33% of the plexuses (or 122 cases), but its origin varied, as it was derived from the ventral rami of the twelfth thoracic to fifth lumbar ventral rami (T12-L5) in 18.67% of the cases. Eight branches of the plexus were found, including seven typical branches and an additional branch. The seven typical branches occured in 100% of cases, and they were the iliohypogastric, ilioinguinal, genitofemoral, lateral cutaneous nerve of the thigh, femoral, obturator nerve and lumbosacral trunk. The additional branch, the accessory obturator nerve occurred in only 3.33% of the cases. In conclusion, the variation pattern of the plexuses occurred on both sides. However, the anatomic variability of the plexuses was not statistically different with regard to either side or gender. The result from this study provided additional information different with regard to either side or gender. The results from this study provided additional information and new insights into the lumbar plexus in terms of its origins, branches, and variations of each branch that might be useful in medicine, anesthesia, surgery and physical therapy.

Anatomical variation course of the lateral femoral cutaneous nerve as it exits the pelvis in Thais from the central region.

The aim of this study was to examine in detail the course and location of lateral femoral cetaneous nerve (LFCN) as it emerges from the pelvis in Thais. The anatomy of the LFCN was studied through the dissection of 107 halves of formalin-embalmed Thai cadavers ranging in age from 37 to 94 years. The LFCN is formed by the union of posterior divisions of ventral rami of the second and third lumbar spinal nerves (L2 – L3). The site at which the nerve exits the pelvis is quite variable. Depending on the anatomical location which varies from superficial and posterior, to medial and deep, to anterior superior iliac spine (ASIS) and origin of the sartorius muscle, five different types as identified by Aszman et all1 were confirmed : type A, posterior to the anterior superior iliac spine across the iliac crest (1.86%); type B, medial to the anterior superior iliac spine and ensheathed in the inguinal ligament (9.34%); type C, medial to the anterior superior iliac spine and ensheathed in the tendinous origin of the sartorius muscle (46.72%); type D, medial to the anterior superior iliac spine located in the interval between sartorius muscle and iliopsoas muscle deep to the inguinal ligament (40.18%); type E, medial to the anterior superior iliac spine, deep to the inguinal ligament, overlying the iliopsoas fascia, and contributing the femoral branch of genitofemoral nerve (1.46%). The majority of the LFCN course and location as it exits the pelvis are type C (46.72%), and type D (40.18%). There is no statistical difference with regard to either gender or side of thigh.

Anatomical variations of the ansa cervicalis in Thais.

The aim of this study was to examine the variation of ansa cervicalis in Thais in terms of its origin, formation and relation to the great vessels of the neck. Anatomical dissections were examined bilaterally in 108 cervical plexuses of Thai cadavers ranging in age from 34 to 87 years. There were 57 male and 51 female cervical plexuses. The ansa cervicalis which consists the first to third cervical ventral rami (C1-C3), is formed by the junction of the superior and inferior roots. Its anatomical course and morphology are complicated by the variable lengths, origins, and relations with the great vessels of the neck. Twenty types of ansa cervicalis were classified into 5 different groups according to the length of ansa loop as compared with the level of cricoid cartilage and the relation of the inferior root of the ansa to the internal jugular vein. Depending on the origins of the inferior and superior roots, each group consisted of various types. Group I and II had long ansa loops with the inferior root lying lateral to the internal jugular vein in group I, and nedial to the vein in group II. Similarly, group III and IV had short loops of the ansa with the inferior root lying lateral to the internal jugular vein in group III, and medial to the vein in group IV. However, group V was not related to the criteria. It was suggested that the majority of ansa cervicalis were found to be group IV and group I. The variation of ansa cervicalis patterns occurred in both sides. This was not statistically different with regard to either gender of side. The results of this study provide additional information and new insights into the variation of the ansa cervicalis which may have useful applications in laryngeal reinnervation surgery and anrsthesia.

The persistence of the median aretery in Thais.

The median artery is a main artery that supplies hand in embryonic period. When the radial and ulnar arteries are well developed, the median artery becomes smaller and soon disappeared. In order to find the incidence of persistant median artery in Thais, we study 266 upper extremities in our Department, 133 of right sides and 133 of left sides. The persistant median artery is found in 22 extremities, or 8%. Further studies reveal that, 77% of median artery are the branch of ulnar artery, 9% of common interosseous artery and 14% of brachial artery. 91% of median artery accompany the median nerve throughout forearm, while 9% traveling superficially in the same plane as supper veins. All of median artery end by joining superficial palmar arch. 95% pass deep to flexor retinaculum, only 5% pass superficial to this retinaculum before joining superficial palmar arch.

Common iliac vein in Thais.

From the dissection of 274 adult Thai cadavers, the sites of the beginning and the sites of the ending of the common iliac vein were recorded. The most common out of ten sites of the beginning was the ala of the sacrum (84%). From six sites of the ending, the most common was the body of the 5th lumbar vertebra (69.0%).