First Experience of Plastination at 4150 Meters Above Sea Level, at the Altitude of La Paz, Bolivia / Primera Experiencia de Plastinación a 4150 Metros sobre el Nivel del Mar, en la Altura de La Paz, Bolivia

SUMMARY: Despite attempts to develop the plastination technique in Bolivia, standardized results have not yet been achieved that could be communicated via scientific publications. There is a great deal of misunderstanding around the technique, confusing it with classic techniques of inclusion in different types of resin, such as polyester and epoxy, but these protocols are not plastination. The aim of this work was to communicate the first standardized room-temperature plastination protocol with silicone in Bolivia, with the unique feature of doing so at the altitude of the city of La Paz, thus constituting the first communication of a plastination technique at 4,150 m.a.s.l. sub sede La Paz, La Paz, Bolivia.

En Bolivia, a pesar de los intentos en el desarrollo de la técnica de Plastinación, aún no se han alcanzado resultados estandarizados que pudieran ser comunicados por medio de publicaciones científicas. Existe una gran confusión al momento de desarrollar la técnica, confundiéndola con técnicas clásicas de inclusión en distintos tipos de reina, como poliéster y epoxy, pero no correspondiendo estos protocolos desarrollados a la técnica de plastinación. En este sentido, el objetivo de esta trabajo consistió en comunicar el primer protocolo estandarizado de plastinación a temperatura ambiente con silicona de Bolivia, con la particularidad de desarrollarlo en la altura de la ciudad de La Paz, constituyéndose, de esta manera, en la primera comunicación de una técnica de plastinación a 4.150 metros sobre el nivel del mar.

Nationwide Stature Estimation from Forearm Length Measurements in Montenegrin Adolescents / Estimación de la Estatura a Partir de Mediciones de la Longitud del Antebrazo en Adolescentes Montenegrinos

SUMMARY: The purpose of this research is to determine a regression equation for estimation of stature from forearm length measurements. This research was carried out on 1200 subjects (604 male and 596 female) among the population of Montenegrin adolescents. The stature and forearm length measurements were taken according to the ISAK protocol, and the data were analyzed statistically. Linear regression analysis determined the prediction of forearm length on the criterion variable a body height at the significance level of p <0.05. These relations are presented in the form of scatter diagram. Thereby, we obtained the coefficient of determination, the multiple correlation coefficients, the partial correlation coefficient, the regression, t-test and standardized beta coefficient. The results of this research study confirmed that forearm length reliably predicts stature in both sexes of Montenegrin adolescents and revealed a very useful finding for physical anthropologists and experts from related fields. It was confirmed that there is a correlation between forearm length and body height (males: 31.9 %, females: 33.3 %).

El propósito de esta investigación fue determinar una ecuación de regresión para la estimación de la estatura a partir de medidas de la longitud del antebrazo. Esta investigación se llevó a cabo en 1200 sujetos (604 hombres y 596 mujeres) entre la población de adolescentes montenegrinos. Las medidas de estatura y longitud del antebrazo se tomaron de acuerdo con el protocolo ISAK y los datos se analizaron estadísticamente. El análisis de regresión lineal determinó la predicción de la longitud del antebrazo en la variable de criterio una altura del cuerpo en el nivel de significación de p <0,05. Estas relaciones se presentan en forma de diagrama de dispersión. De tal manera obtuvimos el coeficiente de determinación, los coeficientes de correlación múltiple, el coeficiente de correlación parcial, la regresión, la prueba t y el coeficiente beta estandarizado. Los resultados de este estudio confirmaron que la longitud del antebrazo predice de manera confiable la estatura en adolescentes montenegrinos de ambos sexos y reveló un hallazgo muy útil para los antropólogos físicos y expertos en áreas relacionadas. Se confirmó que existe una correlación entre la longitud del antebrazo y la altura del cuerpo (hombres: 31,9 %, mujeres: 33,3 %).

Morphological symmetry of the radius and ulna-Can contralateral forearm bones utilize as a reliable template for the opposite side?

The most important precondition for correction of the affected forearm using data from the contralateral side is that the left and right bone features must be similar, in order to develop patient-specific instruments (PSIs) and/or utilize computer-assisted orthopedic surgery (CAOS). The forearm has complex anatomical structure, and most people use their dominant hand more than their less dominant hand, sometimes resulting in asymmetry of the upper limbs. The aim of this study is to investigate differences of the bilateral forearm bones through a quantitative comparison of whole bone parameters including length, volume, bowing, and twisting parameters, and regional shape differences of the forearm bones. In total, 132 bilateral 3D radii and ulnae 3D models were obtained from CT images, whole bone parameters and regional shape were analyzed. Statistically significant differences in whole bone parameters were not shown. Regionally, the radius shows asymmetry in the upper section of the central part to the upper section of the distal part. The ulna shows asymmetry in the lower section of the proximal part to the lower section of the central part. Utilizing contralateral side forearm bones to correct the affected side may be feasible despite regional differences in the forearm bones of around 0.5 mm.

The arcade of Frohse: a systematic review and meta-analysis.

PURPOSE: The structure of the proximal margin of the superficial layer of the supinator muscle is of high interest to many researches. Its tendinous appearance, called the arcade of Frohse, may be clinically important because of its close relationship to the deep branch of the radial nerve passing beneath it and is considered to be the cause of several syndromes. Given the importance of this structure, we aimed to provide a comprehensive and evidence-based review with meta-analytic techniques. MATERIALS AND METHODS: The meta-analysis was performed in adherence to the PRISMA guidelines. Three medical databases were searched in order to identify all potentially eligible articles. Included studies were assessed for quality and the extracted morphological and morphometric data from the relevant articles was analyzed with the use of random effects meta-analysis. RESULTS: A total of 20 studies were included into this meta-analysis. The pooled prevalence of the arcade of Frohse was calculated to be 66% within the adult population and 0% in the fetuses. Other variations regarding the arcade of Frohse were identified as very rare. Analysis of the morphometric parameters revealed the average proportions to be 23.22 mm for the length, 11.05 mm for the width and the mean thickness is 0.67 mm. CONCLUSIONS: The arcade of Frohse is a commonly found structure in adults and thoughtful knowledge of its texture and morphology is especially useful in neurology, neurosurgery, orthopedics, trauma surgery and hand surgery, because it is considered to be the most common source of compression for the deep branch of the radial nerve.

Prevalence, variants, and morphometrics of Palmaris Longus tendon: a magnetic resonance imaging study.

PURPOSE: The palmaris longus (PL) tendon present a high degree of variations; the commonest is its absence which could reach more than 40% in some populations. The PL tendon is highly relevant in hand reconstructive surgery; however, MRI variations of PL tendon have been exceptionally reported. To this, this study investigated PL tendon variations using MRI in a Lebanese population. METHODS: This is a retrospective study of distal forearm MRI examinations to evaluate the presence, anatomical variations and morphometric of PL tendon. The outcomes were set as overall frequency, gender-based and side-base frequencies, correlations between prevalence and gender/side, morphological variants, thickness, and width of PL tendon. RESULTS: The sample comprised 335 patients including a total of 339 MRI scans. The PL was present in 221 wrists (65.2%), and bilaterally in only one (25%) out of the 4 bilateral cases. All PL were located using the Axial T1 views. Univariate and multivariate analyses showed no correlation with side, gender, or Tesla power. The only morphological variation was a reversed PL in 2 cases (0.6%). The mean width was 4.24 ± 1.2 mm. The mean thickness was 2.75 ± 0.6 mm. CONCLUSION: As far as we know, this is the first study to report the total array of variations of PL tendon using MRI, and its prevalence in a Lebanese population. The mean width of PL tendon calculated with high quality MR imaging was found to be similar to that reported by cadaveric studies.

The evaluation of RS1805086 and RS1805065 polymorphisms in Mstn gene and anthropometric properties of national and amateur arm wrestlers / Evaluación de los polimorfismos RS1805086 y RS1805065 en el gen Mstn y las propiedades antropométricas de los luchadores de brazo nacionales y amateurs

The aim of this study is to investigate rs1805086 and rs1805065 polymorphisms of MSTN gene of national and amateur Turkish arm wrestlers and people leading a sedentary lifestyle, and the anthropometric properties such as hand, wrist, and forearm circumferences of national and amateur Turkish arm wrestlers are aimed to be explored. In this study, a total of 79 volunteers who were 24 national (7 females, 17 males) Turkish arm wrestlers, 21 amateur (7 females, 14 males) Turkish arm wrestlers and 34 sedentary people (12 females, 22 males) participated. To analyse the data, Statistical Package for the Social Sciences, SPSS 22 (SPSS Inc., Chicago, IL, USA) was used. As a result of the study, when data on rs1805086 and rs1805065 polymorphisms of MSTN gene were examined respectively, it was found out that MSTN 153KK genotype was 100.0% dominant in both national (n=24) and amateur (n=21) arm wrestlers, and it was 94.12 % dominant in sedentary people. KR genotype was observed in 5.88 % of the sedentary people. The data from the other rs1805065 polymorphism of MSTN gene showed that all participants (n = 45, 100.0 %) were carriers of normal homozygous genotype. Furthermore, for both female group and male group, there found to be statistically significant difference in terms of anthropometric properties. It can be concluded that though there was no significant difference between national and amateur Turkish arm wrestlers in terms of their MSTN gene characteristics; in terms of anthropometric properties, significant differences were discovered. It was found out that on these athletes, not MSTN gene polymorphisms but anthropometric properties were effective.

El objetivo de este estudio fue investigar los polimorfismos rs1805086 y rs1805065 del gen MSTN de luchadores de brazos turcos, nacionales y aficionados, y personas que llevan un estilo de vida sedentario, y las propiedades antropométricas además de las circunferencias de manos, muñecas y antebrazos de los luchadores de brazos turcos nacionales y aficionados. En este estudio, participaron un total de 79 voluntarios: 24 luchadores de brazos turcos nacionales (7 mujeres, 17 hombres), 21 luchadores de brazos turcos aficionados (7 mujeres, 14 hombres) y 34 personas sedentarias (12 mujeres, 22 hombres). Para analizar los datos, se utilizó el Paquete Estadístico para las Ciencias Sociales, SPSS 22 (SPSS Inc., Chicago, IL, EE. UU.). Como resultado del estudio, cuando se examinaron los datos sobre los polimorfismos rs1805086 y rs1805065 del gen MSTN respectivamente, se descubrió que el genotipo MSTN 153KK era 100,0 % dominante en luchadores de brazos nacionales (n = 24) y aficionados (n = 21) , y era 94,12 % dominante en personas sedentarias. El genotipo KR se observó en el 5,88 % de las personas sedentarias. Los datos del otro polimorfismo rs1805065 del gen MSTN mostraron que todos los participantes (n = 45; 100,0 %) eran portadores del genotipo homocigoto normal. Además, tanto para el grupo femenino como para el masculino, se encontró una diferencia estadísticamente significativa en términos de propiedades antropométricas. Se puede concluir que, aunque no hubo una diferencia significativa entre los luchadores de brazos turcos nacionales y aficionados en términos de sus características genéticas MSTN; en términos de propiedades antropométricas, se descubrieron diferencias significativas. Se descubrió que, en estos atletas, no fueron los polimorfismos del gen MSTN sino las propiedades antropométricas las efectivas.

A New Single Volar Approach for Both-Bone Fractures of the Forearm: The Mediolateral Windows Approach Extended.

Fractures of the forearm are common injuries in adults. Particularly, both-bone fractures of the radius and ulna are frequently encountered by orthopedic surgeons. To date, these fractures are typically treated with open reduction and internal fixation, because of the propensity for malunion of the radius and ulna and the resulting loss of forearm rotation. We propose a modification of the classic double approach for both-bone fractures of the distal radius and ulna. Indeed, we described a minimal and anatomic approach to prevent complications such as the heterotopic ossification of the interosseus membrane and vascular-nervous lesions. By a single anterior incision, we utilize 2 windows to expose the medial and lateral compartments of the forearm. In this way, we avoid the handling of the interosseous membrane, and we protect the ulnar, median, and radial nerves from the surgical approach. This technique is indicated for complex distal radius and ulna fractures. We exclude open fractures, and Monteggia, Galeazzi, or Essex-Lopresti lesions. In this report, we describe the surgical anatomy, surgical approach, and complications regarding this approach.

Pronator quadratus muscle flap: a preliminary cadaveric study.

There are very few studies regarding the neurovascular anatomy of pronator quadratus (PQ) or the technique of harvesting it as free functional muscle transfer. The aim of the study was to describe the neurovascular anatomy of PQ, to provide the harvesting technique and review the reported clinical applications. Dissections were performed on four fresh cadaver upper extremities. Measurements of PQ's dimensions, its neurovascular pedicle length, diameter and branching pattern were taken, and photographs were taken. The relation of the neurovascular pedicle to important anatomic landmarks of the forearm was also documented. Identification and raising of the PQ was performed within 30 min on all cases. The neurovascular pedicle was lying over the flexor surface of the interosseous membrane and entered the PQ on its dorsal surface. In all cases, PQ was received its blood supply from the anterior interosseous artery (AIA) with an average length of 12 cm and average diameter of 2.25 mm and it was accompanied by two veins. There were interconnections between the AIA and the ulnar and radial arteries. PQ was innervated by the anterior interosseous nerve with an average length of 12.25 cm. PQ can be easily harvested either as a free or as a pedicled muscle. The learning curve is short. The accompanying vessels and nerve are of adequate length/diameter for microvascular anastomoses and/or neurorrhaphy, respectively. There is no donor site morbidity except the scar. Although there have been sporadic reports on PQ clinical applications, more studies are needed in order to identify the indications/applications in reconstructive surgery.

Morphometric analysis and surgical adequacy of palmaris longus as a tendon graft. A systematic review of cadaveric studies.

INTRODUCTION: The tendon of the palmaris longus is commonly used as a tendon graft in many reconstructive surgeries. Easy to access and at proximity to the hand, the palmaris longus tendon is considered as the optimal tendon source for hand reconstructive surgery. However, and besides its inconsistency, the size of the palmaris longus tendon is reported to show variability. The aim of this study is to look for the surgical adequacy of the palmaris longus tendon by conducting a quantitative synthesis on its length and width in human populations and its correlation with the forearm length. METHODS: Twenty-four studies met the inclusion criteria including 1761 cadaveric limbs. RESULTS: The results were as following: (a) the mean palmaris longus tendon length was of 13.9 ± 2.6 cm, (b) the mean ratio palmaris longus tendon length/forearm length was of 0.545 ± 0.06, (c) the weighted correlation value was of 0.686, and (d) the mean palmaris longus tendon width was of 4.0 ± 1.7 mm. Only five studies reported a palmaris longus tendon length of more than 15 cm. The palmaris longus tendon length was shown to vary between ancestries; the Japanese had the shortest while Malaysian the longest palmaris longus tendons. All studies but one reported a palmaris longus tendon mean width of more than 3 mm where the minimal mean palmaris longus tendon width was of 2.5 mm. CONCLUSION: While the requested length depends on the recipient site and/or type of reconstructive surgery, the palmaris longus tendon often met the required diameter for grafting. Our review demonstrated that while palmaris longus length varies between ancestries, its width is often adequate for grafting. In addition, the forearm length could be a good predictor of palmaris longus tendon length; such correlation could assist surgeons when planning to use palmaris longus tendon as a graft source.

An automatic genetic algorithm framework for the optimization of three-dimensional surgical plans of forearm corrective osteotomies.

Three-dimensional (3D) computer-assisted corrective osteotomy has become the state-of-the-art for surgical treatment of complex bone deformities. Despite available technologies, the automatic generation of clinically acceptable, ready-to-use preoperative planning solutions is currently not possible for such pathologies. Multiple contradicting and mutually dependent objectives have to be considered, as well as clinical and technical constraints, which generally require iterative manual adjustments. This leads to unnecessary surgeon efforts and unbearable clinical costs, hindering also the quality of patient treatment due to the reduced number of solutions that can be investigated in a clinically acceptable timeframe. In this paper, we propose an optimization framework for the generation of ready-to-use preoperative planning solutions in a fully automatic fashion. An automatic diagnostic assessment using patient-specific 3D models is performed for 3D malunion quantification and definition of the optimization parameters' range. Afterward, clinical objectives are translated into the optimization module, and controlled through tailored fitness functions based on a weighted and multi-staged optimization approach. The optimization is based on a genetic algorithm capable of solving multi-objective optimization problems with non-linear constraints. The framework outputs a complete preoperative planning solution including position and orientation of the osteotomy plane, transformation to achieve the bone reduction, and position and orientation of the fixation plate and screws. A qualitative validation was performed on 36 consecutive cases of radius osteotomy where solutions generated by the optimization algorithm (OA) were compared against the gold standard solutions generated by experienced surgeons (Gold Standard; GS). Solutions were blinded and presented to 6 readers (4 surgeons, 2 planning engineers), who voted OA solutions to be better in 55% of the time. The quantitative evaluation was based on different error measurements, showing average improvements with respect to the GS from 20% for the reduction alignment and up to 106% for the position of the fixation screws. Notably, our algorithm was able to generate feasible clinical solutions which were not possible to obtain with the current state-of-the-art method.

Anatomia óssea e muscular do antebraço e mão de Chrysocyon brachyurus (Carnivora, Canidae) / Bone and muscular anatomy of the antibone and handof Chrysocyon brachyurus (Carnivora, Canidae)

O lobo-guará Chrysocyon brachyurus Illiger, 1815, é o maior canídeo da América do Sul, pesa cerca de 25 kg quando adulto e está ameaçado de extinção. Descrições anatômicas contribuem para a complementação das informações sobre espécies silvestres e para implicações conservacionistas, clínicas e cirúrgicas. Objetivou-se descrever os ossos e os músculos do antebraço e mão do lobo-guará. A preparação das peças foi feita a partir dos métodos usuais de dissecação, em animais preservados em solução de formol a 10%. Os espécimes pertencem ao acervo didático do Laboratório de Ensino e Pesquisa em Animais Silvestres da UFU e são provenientes de indivíduos atropelados. Os ossos descritos foram: rádio, ulna, ossos cárpico acessório, cárpico ulnar e cárpico intermédio; ossos cárpicos I, II, III e IV; ossos metacárpicos I, II, III, IV, V; falanges proximais, falanges médias e falanges distais do primeiro ao quinto dedo. Os músculos observados foram: extensor radial do carpo; pronador redondo; braquiorradial; extensor comum dos dedos; extensor ulnar do carpo; extensor lateral dos dedos; supinador; abdutor longo do dedo I; flexor radial do carpo; flexor profundo dos dedos; flexor superficial dos dedos; flexor ulnar do carpo; pronador quadrado; interflexor; lumbricais; abdutor curto dos dedos I e II e flexor curto do dedo I.

The maned wolf Chrysocyon brachyurus (Illiger, 1815) is the largest canid in South America, weighs about 25 kg as an adult and is threatened of extinction. Anatomical descriptions contribute to the complementation of information on wild species and for conservation, clinical and surgical implications. The purpose of this study was to describe the bones and muscles of the forearm and hand of the maned wolf. The methodology was through the usual dissecting methods in animals preserved in 10% formalin solution. The animals belong to the didactic collection of the Laboratory of Teaching and Research in Wild Animals of the UFU and come from run over. The bones evaluated were: radius, ulna, carpal accessory, carpi ulnar and carpi intermedium; carpal bones I, II, III and IV; metacarpal bones I, II, III, IV, V; proximal phalanges, middle phalanges and distal phalanges from first to fifth finger. The muscles observed were: radial extensor carpal; pronator round; brachioradial; common extensor of fingers; ulnar carpal extensor; lateral extensor of the fingers; supinator; abductor long finger I; flexor carpi radialis; flexor deep fingers; superficial flexor of the fingers; ulnar flexor of the carpus; square pronator; interflexor; lumbrils; short abductor of fingers I and II and short flexor of finger I.

Anatomia óssea e muscular do antebraço e mão de Chrysocyon brachyurus (carnivora, canidae) / Bone and muscular anatomy of the antibone and hand of Chrysocyon brachyurus (carnivora, canidae)

O lobo-guará Chrysocyon brachyurus Illiger, 1815, é o maior canídeo da América do Sul, pesa cerca de 25 kg quando adulto e está ameaçado de extinção. Descrições anatômicas contribuem para a complementação das informações sobre espécies silvestres e para implicações conservacionistas, clínicas e cirúrgicas. Objetivou-se descrever os ossos e os músculos do antebraço e mão do lobo-guará. A preparação das peças foi feita a partir dos métodos usuais de dissecação, em animais preservados em solução de formol a 10%. Os espécimes pertencem ao acervo didático do Laboratório de Ensino e Pesquisa em Animais Silvestres da UFU e são provenientes de indivíduos atropelados. Os ossos descritos foram: rádio, ulna, ossos cárpico acessório, cárpico ulnar e cárpico intermédio; ossos cárpicos I, II, III e IV; ossos metacárpicos I, II, III, IV, V; falanges proximais, falanges médias e falanges distais do primeiro ao quinto dedo. Os músculos observados foram: extensor radial do carpo; pronador redondo; braquiorradial; extensor comum dos dedos; extensor ulnar do carpo; extensor lateral dos dedos;supinador; abdutor longo do dedo I; flexor radial do carpo; flexor profundo dos dedos; flexor superficial dos dedos; flexor ulnar do carpo; pronador quadrado; interflexor; lumbricais; abdutor curto dos dedos I e II e flexor curto do dedo I.

The maned wolf Chrysocyon brachyurus (Illiger, 1815) is the largest canid in South America, weighs about 25 kg as an adult and is threatened of extinction. Anatomical descriptions contribute to the complementation of information on wild species and for conservation, clinical and surgical implications. The purpose of this study was to describe the bones and muscles of the forearm and hand of the maned wolf. The methodology was through the usual dissecting methods in animals preserved in 10% formalin solution. The animals belong to the didactic collection of the Laboratory of Teaching and Research in Wild Animals of the UFU and come from run over. The bones evaluated were: radius, ulna, carpal accessory, carpi ulnar and carpi intermedium; carpal bones I, II, III and IV; metacarpal bones I, II, III, IV, V; proximal phalanges, middle phalanges and distal phalanges from first to fifth finger. The muscles observed were: radial extensor carpal; pronator round; brachioradial; common extensor of fingers; ulnar carpal extensor; lateral extensor of the fingers; supinator; abductor long finger I; flexor carpi radialis; flexor deep fingers; superficial flexor of the fingers; ulnar flexor of the carpus; square pronator; interflexor; lumbrils; short abductor of fingers I and II and short flexor of finger I.

Anátomo-radiografia dos ossos longos do membro torácico do Tamandua tetradactyla / Anatomo-radiography of long-bones in thoracic limb of Tamandua tetradactyla

Objetivou-se descrever os acidentes anatômicos dos ossos longos do membro torácico de Tamandua tetradactyla por meio de análises macroscópicas e radiográficas. Foram utilizados 34 espécimes, que foram a óbito por atropelamento. A avaliação do úmero demonstrou as mesmas estruturas presentes nos animais domésticos, além de outras sem prévia descrição. Já no antebraço, rádio e ulna se apresentaram completamente separados, e apesar de, como o úmero, serem identificados alguns dos mesmos acidentes anatômicos descritos em outras espécies, também notamos particularidades. Todas as estruturas descritas na análise macroscópica foram identificadas à radiografia, quando realizada em pelo menos duas projeções ortogonais. As estruturas anátomo-radiográficas dos ossos longos do T. tetradactyla demonstraram grande variaçãoanatômica em comparação a outros mamíferos, o que torna a referida espécie muito singular. Assim o conhecimento de suas particularidades é fundamental para abordagens clínico-cirúrgicas mais seguras.

The objective was to describe the anatomical accidents of the long bones of the thoracic limb of Tamandua tetradactyla by means of macroscopic and radiographic analyzes. We used 34 specimens, which were death by running over. Evaluation of the humerus demonstrated the same structures present in domestic animals, besides others without previous description. In the forearm, radius and ulna were completely separated, and although, like the humerus, some of the same anatomical accidents described in other species were identified, we also noticed particularities. All the structures described in the macroscopic analysis were identified on radiography, when performed in at least two orthogonal projections. The anatomic-radiographic structures of the long bones of T. tetradactyla showed great anatomical variation compared to other mammals, which makes the species very unique. Thus knowledge of their particularities is fundamental for safer clinical-surgical approaches.

Extensor Carpi Ulnaris Tendon Anatomy May Mimic Tears.

Background: Asymptomatic, incidental extensor carpi ulnaris (ECU) tendon abnormalities are frequently noted on imaging studies of the wrist. The aim of this investigation was to determine if variations in gross tendon anatomy existed that could possibly account for these findings on MRI and ultrasound (US) imaging. Methods: The upper extremities of eleven (6 male and 5 female) formalin preserved cadavers were dissected and examined under loupe magnification with attention to the dorsal-ulnar wrist and hand and the ECU tendon. The tendons were inspected for anatomic variations, degenerative changes, and any other pathologies. The presence of intra-tendinous splits arising within the ECU tendon was noted and measured. The distances of the splits from the distal tendon insertion and the edge of the extensor retinaculum were recorded. Statistical correlations between age and the tendon splits were considered using R-squared to assess a linear regression. Results: 17 ECU tendons were dissected and examined, and 5 ECU tendons were excluded due to poor preservation of that upper extremity; all five were right sided upper extremities. Eleven of the 17 specimens demonstrated at least one split in the distal tendon: Seven had 1 split, 1 had 2 splits, and 3 had 3 splits. The mean length of the tendon split was 3.52 cm. The mean distance of the distal edge of the split to the tendon insertion site was 2.4 cm. A linear regression was calculated and showed no correlation between age and number of tendon splits. Conclusions: 64% of specimens showed a longitudinal split in the distal ECU tendon. The location of these frequent splits corresponds to imaging abnormalities on MRI and US in prior studies.

Nerve transfer of the anterior interosseous nerve to the thenar branch of the median nerve - an anatomical and histological analysis.

OBJECTIVE: Nerve transfer has become a vital method in the reconstruction of hand function. Reconstructing the motor function to the thenar musculature has proven to be difficult and is rarely satisfactory following direct anatomic repair. The aim of this investigation was to describe the anatomic results obtained by transferring the anterior interosseous nerve to the thenar branch of the median nerve and analyze the histomorphometric results. MATERIAL AND METHODS: Nerve transfers were performed in 15 fresh anatomic specimens. Nerve samples were excised from 13 fresh specimens and histologically investigated. The nerve diameter, fascicle number, and cross-sectional area of the individual fascicles were measured. RESULTS: The results of this investigation revealed that the anterior interosseous nerve and the thenar branch of the median nerve could be identified at their expected locations and a tension-free coaptation could be achieved. The anterior interosseous branch had a mean number of 606 ± 254 axons vs. 2160 ± 1326 in the thenar branch (p < 0.001). The anterior interosseous branch had a mean density of axons per fascicle mm2 of 2398 ± 829 vs. 3012 ± 740 in the thenar branch (p = 0.390). The ratio of axons between the thenar branch of the median nerve and the anterior interosseous nerve yielded a mean of 1:4.16. CONCLUSION: Nerve transfer of the anterior interosseous nerve to the thenar branch of the median nerve should be considered as a viable option but remains a subject of investigation owing to its critical axon ratio. Furthermore, larger clinical studies will be required to validate or neglect this nerve transfer.

Redefining Zone II: Anatomy of the Flexor Digitorum Superficialis Insertion.

BACKGROUND: Flexor zone II is defined as the region spanning the proximal aspect of the A1 pulley to the insertion of the flexor digitorum superficialis (FDS) tendon. Descriptions of the FDS insertion are inconsistent in the literature, but zones of injury are frequently determined with reference to superficial landmarks. The purpose of this study was to describe the footprint of the FDS insertion and define its relationship to the proximal interphalangeal (PIP) skin crease. METHODS: The FDS insertion on the index, middle, ring, and small fingers was dissected in 6 matched pairs of fresh-frozen cadaveric hands. A Kirschner wire was used to mark the level of the PIP skin crease on bone before measurements of the FDS footprint and its position relative to the PIP skin crease were made using digital calipers. RESULTS: The radial and ulnar FDS slips inserted a mean distance of 3.22 mm from the distal aspect of the PIP skin crease and varied by digit. The mean distal extent of the FDS insertion was 8.29 mm. The mean length of the insertion of each FDS slip was 5.15 mm and the mean width was 1.9 mm. CONCLUSIONS: The radial and ulnar FDS slips insert on average 3.22 mm distal to the PIP skin crease and vary by digit. Knowledge of the FDS insertion is clinically relevant when differentiating between flexor zone I and zone II injuries, planning surgical approaches to the finger, and in guiding patient expectations for surgery given the variability in outcome based on zone of injury.

The 7 Structures Distal to the Elbow That Are Critical to Successful Anterior Transposition of the Ulnar Nerve.

Background: Ulnar nerve transposition (UNT) surgery is performed for the treatment of cubital tunnel syndrome. Improperly performed UNT can create iatrogenic pain and neuropathy. The aim of this study is to identify anatomical structures distal to the medial epicondyle that should be recognized by all surgeons performing UNT to prevent postoperative neuropathy. Methods: Ten cadaveric specimens were dissected with attention to the ulnar nerve. Intramuscular UNT surgery was simulated in each. Distal to the medial epicondyle, any anatomical structure prohibiting transposition of the ulnar nerve to a straight-line course across the flexor-pronator mass was noted and its distance from the medial epicondyle was measured. Results: Seven structures were found distal to the medial epicondyle whose recognition is critical to ensuring a successful anterior transposition of the ulnar nerve: (1) Branches of the medial antebrachial cutaneous (MABC) nerve; (2) Osborne's fascia; (3) branches from the ulnar nerve to the flexor carpi ulnaris (FCU); (4) crossing vascular branches from the ulnar artery to the FCU; (5) the distal medial intermuscular septum between the FCU and flexor digitorum superficialis (FDS); (6) the combined muscular origins of the flexor-pronator muscles; and (7) the investing fascia of the FDS. Measurements are given for each structure. Conclusions: Poor outcomes and unnecessary revision surgeries for cubital tunnel syndrome can be avoided with intraoperative attention to 7 structures distal to the medial epicondyle. Surgeons should expect to dissect up to 12 cm distal to the medial epicondyle to adequately address these and prevent kinking of the nerve in transposition.

The radial head size in relation to osseous landmarks of the forearm.

PURPOSE: Radial head fractures are regularly treated with radial head arthroplasty. To prevent limited motion or pain, the implant's size should match its normal anatomy. Preoperative estimation of the radial head size helps in finding the correct head component. The aim of this study was to measure bony landmarks in proximity to the radial head to estimate the required size of a prosthesis preoperatively. METHODS: Anatomical landmarks on 82 elbows from 41 embalmed specimens (19 male, 22 female) were measured using a digital caliper after removal of the specimens' tissue: the largest and smallest radial head diameter, length of the radius (styloid tip to radial head articular surface), and the length of the ulna (styloid tip to coronoid base). Additionally, cranio-caudal and antero-posterior diameters of the capitulum on scaled lateral elbow X-ray images were measured. RESULTS: The mean largest and smallest radial head diameters were 24.2 mm (± 2.2, range 19.9-30.3; ICC = 0.992) and 22.5 mm (± 2.0, range 18.9-27.5; ICC = 0.985). The mean radius length was 23.8 cm (± 1.6, range 20.1-27.1; ICC = 0.986), and the mean ulna length was 23.1 cm (± 1.6, range 19.3-26.3; ICC = 0.969). The mean antero-posterior capitulum diameter was 16.2 mm (± 2.4, range 10.4-21.0; ICC = 0.506), and the mean cranio-caudal diameter was 17.0 mm (± 3.3, range 10.0-23.9; ICC = 0.529). The highest correlation to radial head diameters could be shown for diameters of the contralateral radial head and the radius length. CONCLUSIONS: For preoperative estimation of the radial head, the diameters of the contralateral radial head or the radius length are the most accurate.

Anatomical variations of the caudomedial antebrachial muscles in the crab-eating fox (Cerdocyon thous) / Variaciones anatómicas de los músculos caudo-mediales del antebrazo del zorro perruno (Cerdocyon thous)

The crab-eating fox (Cerdocyon thous) is a wild canid distributed in South America, which is susceptible to traumas caused by captors, accidents on roads, and traps. Due to these events their thoracic limbs can be involved at the level of the forearm, therefore, knowledge of the gross anatomy of its muscles is important in order to develop clinical and surgical procedures at this level compared with the domestic dog. The main objective of this investigation was report the intra and interspecific anatomical variations of the caudomedial forearm muscles in Cerdocyon thous in comparison mainly with the domestic dog. Six dead specimens from wildlife care centres of CORPOCALDAS were used. These were fixed with a solution of formaldehyde, mineral oil and phenic acid. Both thoracic limbs of each specimen were dissected from superficial to deep, emphasizing the caudomedial part of the forearm in order to review the anatomical characteristics of each muscle. These muscles were similar to those reported in the domestic dog, but some variations were observed such as the innervation of the pronator teres muscle by the musculocutaneous nerve in a specimen unilaterally; the formation of an accessory muscle from the ulnar head of the flexor carpi ulnaris muscle in most specimens; and the vestigial presence of the anconeus epitrochlearis muscle in a specimen bilaterally.

El zorro perruno (Cerdocyon thous) es un cánido silvestre distribuido en Sudamérica, el cual es susceptible a traumas causados por captores, accidentes en carreteras y trampas, donde pueden verse involucrados sus miembros torácicos a nivel del antebrazo, por lo tanto, conocer la anatomía de sus músculos es importante, ya que ésta servirá como base en la realización de procedimientos clínicos y quirúrgicos a este nivel en comparación con el perro doméstico. El objetivo principal de esta investigación fue reportar las variaciones anatómicas intra e interespecíficas de los músculos caudo-mediales del antebrazo de C. thous en comparación principalmente con el perro doméstico. Se utilizaron seis especímenes muertos bajo la jurisdicción de CORPOCALDAS. Estos se fijaron con una solución en mezcla de formaldehído, aceite mineral y ácido fénico. Se diseccionaron de superficial a profundo los dos miembros torácicos de cada espécimen, haciendo énfasis en la parte caudo-medial del antebrazo para revisar las características anatómicas de cada músculo, las cuales fueron similares a las reportadas al perro doméstico, pero se observó en un espécimen de manera unilateral la inervación al músculo pronador teres por parte del nervio musculocutáneo; en la mayoría de especímenes se observó la formación de un músculo accesorio a partir de la cabeza ulnar del músculo flexor ulnar del carpo; y en un espécimen la presencia vestigial del músculo ancóneoepitroclear.

The median nerve penetrating through the radial head of the flexor digitorum superficialis muscle: Case report.

The forearm is a body region of numerous anatomical variations. Due to its favorable anatomy flexor digitorum superficialis muscle (FDS) is commonly used in tendon transfer surgeries. In this study a unique combination of abnormalities was found in a single forearm: the flexor digitorum superficialis muscle penetrated by the median nerve, one of the flexor digitorum superficialis tendons early division and absence of the palmaris longus muscle. Described variation potentially may lead to the clinical manifestation of the median nerve compression and should be also considered during FDS surgery.