Relationship between the Branching Patterns of the Radial Nerve and Supinator Muscle.

The posterior interosseous nerve (PIN) innervates the posterior compartment muscle of the forearm and is a continuation of the deep branch of the radial nerve. The anatomic descriptions of PIN vary among different authors. This study investigated the distribution patterns of PIN and its relationships to the supinator muscle. This study investigated which nerves innervate the posterior compartment muscles of the forearm, the radial nerve, and the PIN, using 28 nonembalmed limbs. Also, the points where the muscle attaches to the bone were investigated. The measured variables in this study were measured from the most prominent point of the lateral epicondyle of the humerus (LEH) to the most distal point of the radius styloid process. For each specimen, the distance between the above two points was assumed to be 100%. The measurement variables were the attachment area of the supinator and branching points from the radial nerve. The attachment points of the supinator to the radius and ulna were 47.9% ± 3.6% and 31.5% ± 5.2%, respectively, from the LEH. In 67.9% of the specimens, the brachioradialis and extensor carpi radialis longus (ECRL) were innervated by the radial nerve before superficial nerve branching, and the extensor carpi radialis brevis (ECRB) innervated the deep branch of the radial nerve. In 21.4% of the limbs, the nerve innervating the ECRB branched at the same point as the superficial branch of the radial nerve, whereas it branched from the radial nerve in 7.1% of the limbs. In 3.6% of the limbs, the deep branch of the radial nerve branched to innervate the ECRL. PIN was identified as a large branch without divisions in 10.7% and as a deep branch innervating the extensor digitorum in 14.3% of the limbs. The anatomic findings of this study would aid in the diagnosis of PIN syndromes.

The neurovascular structures in the triangular space of the upper limb: an anatomical study / Las estructuras neurovasculares en el espacio triangular del miembro superior: un estudio anatómico

The aim of this study was to investigate the neuromuscular distribution after passing through the triangular space of the shoulder. Thirty-five specimens from 18 adult Korean cadavers (12 males and 6 females, age ranging from 42-102 years) were used in the study. This study analyzed the order in which the artery entered the muscle from that point the artery passed through the triangular space. The incidence of the first branch of the circumflex scapular artery was 11.4 % for infraspinatus, 5.7 % for teres major, 25.7 % for teres minor, 20.1 % for long head of biceps brachii, 25.7 % for subscapularis, and 11.4 % for subcutaneous tissue. This study investigated the incidence of lack of blood supply from the artery in the triangular space. This incidence was 27.8 % for infraspinatus, 13.0 % for teres major, 5.6 % for teres minor, 38.8 % for long head of triceps brachii, and 14.8 % for subscapularis. Four specimens showed arterial distribution in all surrounding muscles. One specimen identified the nerve branch to innervate teres minor of triangular space of shoulder. The results of this study will be helpful in clinical practice.

El objetivo de este estudio fue investigar la distribución neuromuscular después de pasar a través del espacio triangular del hombro. Para el estudio fueron utilizados treinta y cinco especímenes de 18 cadáveres adultos coreanos (12 varones y 6 mujeres, con una edad de 42-102 años). Se analizó el orden en que la arteria penetra en el músculo y continúa a través del espacio triangular. La incidencia de la primera rama de la arteria circunfleja escapular fue: 11,4 % en el músculo infraspinoso, 5,7 % en el músculo redondo mayor, 25,7 % en el músculo redondo menor, 20,1% en la cabeza larga del músculo bíceps braquial, 25,7 % en el músculo subescapular y 11,4 % en el tejido subcutáneo. Este estudio investigó la incidencia de la falta de suministro de sangre de la arteria en el espacio triangular. Se observó incidencia de 27,8 % para el músculo infraespinoso, 13,0 % para el músculo redondo mayor, 5,6 % para el músculo redondo menor, 38,8 %, para la cabeza larga del músculo tríceps braquial y 14,8 % para el músculo subescapular. Cuatro especímenes mostraron distribución arterial en todos los músculos circundantes. En un caso se identificó la rama nerviosa para el músculo redondo menor en espacio triangular del hombro. Los resultados de este estudio serán útiles en anatomía clínica.

Botulinum Toxin Injection-Site Selection for a Smooth Shoulder Line: An Anatomical Study.

Introduction. This study aimed to improve the accuracy of manual needle placement into the trapezius (TM) for smooth shoulder line. Methods. For macroscopic study 12 TMs and for microscopic study 4 cadavers were detached and then sampled, 1⁎1 cm at the four points from the origin to insertion site (0% at the most lateral point of external occipital protuberance and 100% at the most lateral point of acromion). Results. Most of the nerve endings observed during macroscopic investigations were concentrated in the 60-80% region, and the second most distributed region was the 40-60% region. The microscopic results revealed that the 60-80% region on the reference line had the most dense neuromuscular junction area, while the 40-60% and 80-100% areas were similar in their neuromuscular junction densities. Discussion. These anatomical results will be useful in clinical settings especially for cosmetic surgeons.

Median nerve location change evaluated by soft cadaver dissection according to the forearm movement / Cambio de posición del nervio mediano evaluado mediante disección cadavérica blanda según el movimiento del antebrazo

The aim of this study was to examine the change in median nerve location according to forearm movement. Thirty fresh specimens from 15 adult Korean cadavers (10 males and five females; age range, 53­91 years) were examined. We measured the motor entry point according to normal and pronated positions of the forearm. The x and y coordinates of the first motor entry point (MEP) in the normal position were 1.6±0.6 cm and 2.8±1.3 cm, respectively. The depth of the MEP was 1.5±0.3 cm. The x and y coordinates of the second MEP were 1.3±0.3 cm and 4.7±1.7 cm, respectively. The depth of the MEP was 1.4±0.2 cm. The x and y coordinates of first MEP with the forearm in the pronated position were 1.9±0.7 cm and 2.3±0.8 cm. respectively. The depth of the MEP was 1.7±0.4 cm. The x and y coordinates of the second MEP were 1.6±0.7 cm and 4.4±1.7 cm, respectively. The depth of the MEP was 1.6±0.3 cm. The differences in locations according to movement of the nerve branch were 0.3 cm, and depths were 0.2 cm. The pronated position results of this study will be clinically helpful.

El objetivo fue examinar el cambio de posición del nervio mediano de acuerdo con el movimiento del antebrazo. Se examinaron 30 muestras frescas de 15 cadáveres adultos coreanos (10 hombres y 5 mujeres) con edades entre 53­91 años. Se midió el punto de entrada motor de acuerdo con las posiciones normales y pronación del antebrazo. Las coordenadas X e Y del primer punto de entrada motor (PEM) en la posición normal fueron de 1,6±0,6 cm y 2,8±1,3 cm, respectivamente. La profundidad del PEM fue de 1,5±0,3 cm. Las coordenadas X e Y del segundo PEM fueron 1,3±0,3 cm y 4,7±1,7 cm, respectivamente. La profundidad del PEM fue 1,4±0,2 cm. Las coordenadas X e Y del primer PEM del antebrazo en posición de pronación fueron 1,9±0,7 cm y 2,3±0,8 cm, respectivamente. La profundidad del PEM fue 1,7±0,4 cm. Las coordenadas X e Y del segundo PEM fueron 1,6±0,7 cm y 4,4±1,7 cm, respectivamente. La profundidad del PEM fue 1,6±0,3 cm. Las diferencias en las ubicaciones de acuerdo con el movimiento del ramo nervioso fueron de 0,3 cm, y las profundidades fueron de 0,2 cm. Los resultados de la posición de pronación de este estudio serán útiles en trabajos clínicos.

Effective zone of botulinum toxin a injections in hallux claw toe syndrome: an anatomical study.

INTRODUCTION: The aim of this study was to determine the anatomical location of the motor points of the flexor hallucis longus (FHL) and brevis (FHB) muscles for an effective motor point block. METHODS: Twenty cadavers were used for this study. For the FHL, we identified the line between the medial and lateral epicondyle of the femur and the line joining the prominent point on the surface of the medial malleolus of the tibia and the lateral malleolus of the fibula. For the FHB, we identified the line between the middle-lowest point of the great toe and the middle-lowest point of the sole of the foot. RESULTS: The dense area of the motor points was located at 40-70% for the FHL and 50-70% for the FHB. CONCLUSION: An injection area of 50-60% on the reference line for the FHL and FHB is suggested.

Anatomic localization of motor entry point of superficial peroneal nerve to peroneus longus and brevis muscles.

This study examined the anatomic location of the motor entry point (MEP) and branching point at the proximal and distal points of the tendon of the peroneal muscle by visual observation. Forty-three fresh legs of 25 adult bodies which had been donated to science were investigated in this study. The mean length of the reference line between the most proximal point of the head of the fibula (PHF) and the most distal point of the malleolus of the fibula (DMF) was 33.4 ± 2.5 cm. The MEPs of the peroneus longus (PL) and peroneus brevis (PB) gathered from 20 to 40% (7.0-13.0 cm) and 40 to 60%, respectively. The branching point where the nerve was divided to innervate the PL and PB was 10% and 28% from the PHF, respectively. These anatomic results suggest appropriate areas where to inject phenol or other agents for a MEP block in the case of a spastic lower extremity as well as guidelines for an electromyography conduction test.

Morphometric trajectory analysis for the C2 crossing laminar screw technique.

This paper reports a morphometric study of the C2 laminae to provide quantitative anatomical data for safe crossing laminar screw placement. A valid trajectory is essential for C2 crossing laminar screw placement. Although several clinical technique notes and modifications to define a safe screw trajectory have been introduced in the recent years, no morphometric analysis has been performed to confirm the accuracy of screw trajectory using this technique. In this study, morphometric analysis was performed on 100 Korean C2 three-dimensional reconstruction CT images. The reconstructive C2 vertebrae from the post-edge of the spinal canal to the spinal process were divided into several zones, 1 mm each. Each zone was chosen as the entry point to imitate a crossing laminar screw (3.5 mm diameter) placement. In each 1-mm zoned trajectory, the screw pass ratio (PR), safe screw angle range (SAR) and maximum screw length (MSL) were measured and compared with the data from the other zoned trajectories. The zone '5-6 mm posterior to the post-edge of the spinal canal' was found to be a more feasible and safer entry point for guiding a crossing laminar screw placement than the other zones because this zone could provide a trajectory with maximal PR (85%), SAR (9.57 +/- 4.36 masculine) and a larger MSL (21.74 +/- 2.44 mm) than the other areas. The recommended safe screw angle in the axial plane is 49.68 +/- 4.94 to 59.19 +/- 4.70 masculine. However, the screw angle can vary considerably according to the individual variance. A preoperative evaluation of the screw trajectory is essential for safe screw placement using this technique.

Inhibition of nitric oxide synthase induces increased production of growth-associated protein 43 in the developing retina of the postnatal rat.

We investigated the effects of N(G)-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor, on retinal development in the postnatal rat by immunocytochemistry and immunoblotting using antisera against neuronal nitric oxide synthase (nNOS) or growth-associated protein 43 (GAP-43). An nNOS-immunoreactive band of 155 kDa and a GAP-43-immunoreactive band of 48 kDa were present in the extracts of both control and L-NAME-treated rat retinas. The intensity of the nNOS-immunoreactive band was much weaker in the treated rats, whereas the intensity of the GAP-43-immunoreactive band of 48 kDa was much stronger in the treated rats. Much stronger GAP-43 immunoreactivity was visible in the inner plexiform layer (IPL) of the treated retinas at P10, P14 and P21. Our findings suggest that NO may play an important role in the maturation of the IPL in the developing rat retina.