Multiple Muscular Variations in the Neck, Upper Extremity, and Lower Extremity Biased toward the Left Side of a Single Cadaver

Although numerous reports have found accessory or supernumerary muscles throughout the human body, multiple appearances of these variations biased toward one side of body are rare. We report a 76-yr-old male cadaver with an accessory head of the biceps brachii and palmaris profundus, and a muscular slip between the biceps femoris and semitendinosus on the left side in addition to a bilateral accessory belly of the digastric muscle. No remarkable nervous, vascular, or visceral variation accompanied these variations. An interruption of normal somitogenesis or myogenesis may be a cause of these variations.

Anatomical study of the nerve regeneration after selective neurectomy in the rabbit: clinical application for esthetic calf reduction / 대한해부학회지

The purposes of this study were therefore to characterize the degeneration and regeneration of nerves to the calf muscles after selective neurectomy, both macroscopically and microscopically, and to determine the incidence of such regeneration in a rabbit model. Seventy four New Zealand white rabbits were used. Selective neurectomy to the triceps surae muscles was performed, and the muscles were subsequently harvested and weighed 1-4 months postneurectomy. The gastrocnemius muscles were stained with Sihler's solution to enable the macroscopic observation of any nerve regeneration that may have occurred subsequent to neurectomy. The change in triceps surae muscle weight was measured along the time course of the experiment. After neurectomy, nerve degeneration was followed by regeneration in all cases. The weight of the triceps surae muscle decreased dramatically between completion of the neurectomy and 1 month postneurectomy, but increased thereafter. The nerve branches were weakly stained with Sihler's solution until 2 months postneurectomy, and then strongly stained after 3 months. The number of myelinated axons was decreased at 2 month after neurectomy compared to nonneurectomized controls, but then gradually increased thereafter. Although there are currently no reports on the incidence of recovery after calf reduction, it may be a very common occurrence in the clinical field based on our findings. The findings of this study provide fundamental anatomical and surgical information to aid planning and practice in calf-reduction surgery.

Anatomy of the Femoral Attachment Site of the Anterior Cruciate Ligament and the Posterolateral Structures Related to the Stability of the Knee Joint / 대한해부학회지

The anterior cruciate ligament (ACL) and the posterolateral structures are functionally important structures that assist with the stability of the knee joint. Sport-related injuries to these structures and reconstructive surgery are becoming more frequent. However, the anatomic characteristics and the relationship between these structures are not well understood. We measured the morphological characteristics of the posterolateral structures of the knee and the ACL, and we identified the anatomic relationship between the center of the femoral attachment area of the ACL and other femoral structures. We dissected 34 cadaveric knees with no signs of previous surgery, knee abnormality, or disease. The lateral collateral ligament (LCL) and the popliteus tendon (PLT) were present in all knees, although the popliteofibular ligament (PFL) was not present in 20.6% of knees. The mean length of the LCL was 51.99 mm and differed significantly between men and women (P<0.05). The mean length of the PLT was 21.59 mm, and the mean length of the PFL was 18.49 mm. In 67.7% of knees, the PLT was attached to the inferior aspect of the femoral attachment of the LCL, and the femoral attachment of the PLT was covered by the bundle of the LCL. The ACL was distinguished into anteromedial (AM) and posterolateral (PL) bundles in all knees. The mean lengths of the AM and PM bundles were 22.14 mm and 15.98 mm, respectively. The measured lengths in each bundle differed significantly between men and women (P<0.05). The mean distance between the center of the femoral attachment area of the ACL and the intercondylar line was 8.36 mm in the AM bundle, 15.98 mm in the PL bundle, and 10.96 mm in the entire ACL. The mean distance between the center of the femoral attachment area of the ACL and the medial border of the lateral condyle was 8.14 mm in the AM bundle, 7.36 mm in the PL bundle, and 8.45 mm in the entire ACL.

Distribution of Purinergic Receptor and Vanilloid Receptor Participating in Micturition and Reciprocal Relationship between Them / 대한해부학회지

Two of the synaptic receptors involved in the regulation of micturition, P2X(3) receptor, which is operated by ATP, and vanilloid receptor 1 (VR1), which is operated by capsaicin, are regarded as newcomers. To investigate the possibility that these receptors act as therapeutic targets for treatment of an overactive bladder, we investigated their distribution and reciprocal relationship. Eight-week-old Sprague Dawley rats were injected with retrograde nerve tracer within the bladder wall, and 15 rats were injected with 0.5% acetic acid inside the bladder. After a week, the animals were killed, and their dorsal root ganglia (DRG) at the levels of L6 and S1 were harvested. Immunohistochemistry or Western blot analysis of P2X(3) and VR1 were performed on the DRG. The DRG neurons with afferent fibers from the bladder had increased expression of VR1 and downregulated P2X(3) receptors. The P2X(3) receptor and VR1 seemed to account for the important parts of the hypersensitivity of the inflammatory bladder. We conclude that the simultaneous modulations of both P2X(3) receptor and VR1 may have a synergic effect on the treatment of overactive bladder and may produce greater response rates.

Variations of the Superficial Brachial Artery in Korean Cadavers

The superficial brachial artery (SBA), a branch of the axillary artery, is one of the most common arterial variations in this area. While it is more vulnerable to accidental arterial injection or injury, it could be useful for the nourishment of a medial arm skin free flap. To analyze the relationship between the SBA of axillary origin and segmental variation of the axillary artery, we dissected 304 arms of Korean cadavers. We found an SBA of axillary origin in 12.2% of cadaveric arms. Unilateral occurrence was detected in 16 cadavers and bilateral in 10. SBAs gave rise to radial and ulnar arteries in the cubital fossa (8.9%), continued in the forearm as the radial artery (2.3%), or ended in the upper arm (1.0%). The SBA ended as ulnar artery was not found in any of the cadavers. The bifurcation of the SBA into the radial and ulnar arteries, presence of an SBA that ends in the upper arm, and the lack of continuation as the ulnar artery are characteristics of SBAs in Korean cadavers.

The Subscapular Artery and Its Relationship with the Brachial Plexus / 대한해부학회지

The change of arising site of branches from the axillary artery determines it's topographic relationship with the brachial plexus because of closeness between the artery and the plexus. Variation of the subscapular artery (SSA) should be concerned when it is used for the source artery of some flaps, especially focusing on the variation of branching pattern and site of origin and relationships with the brachial plexus. In some cases of absence of SSA, if the circumflex scapular and the thoracodorsal arteries arise from the variable portion of the axillary artery separately, they might change the relationships with the brachial plexus. This study was performed to clarify the relationships between the subscapular artery and the brachial plexus according to the variation of the origin of the SSA and its branch. Two hundred seventeen axillae from 110 Korean cadavers were used for this study. SSA was found in 87.1% of cases, while in 12.9%, the circumflex scapular and the thoracodorsal arteries arose from the axillary artery (AA) seperately. SSA arose most frequently from the third part of the AA (63.6%), and in 4/5 of these cases, it ran behind the radial and ulnar nerves. When it arose from the second part (18.9%) or from the first part (4.6%) of AA, it mostly ran over anterior to the medial cord or/and the ulnar nerve. In 41.9% of the cases, a posterior circumflex humeral artery made a common trunk with the SSA or came from the circumflex scapular artery. In 28.1% of the materials, the SSA made a common trunk with a lateral thoracic artery especially when it arose from the first or second part of AA. After running a mean distance of 2.2 cm from AA, SSA was divided into the circumflex scapular and the thoracodorsal arteies. The SSA gave off the branches to the subscapularis in 68.7% of the cases, and the branches to the serratus anterior in 76.0%.

Morphological Analysis of the Effect of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin on the Peripheral Nervous System of Mouse / 대한해부학회지

Toxicity of TCDD on the peripheral nerve has not yet been clear even though there are many reports about its toxicity on various organs of human and other animals. This study was designed to clarify the effect of TCDD on the peripheral nerve by the morphometric and electron microscopic analysis. Fourty mg/kg of TCDD was injected to 4 week-old C57BL/6J mice intraperitoneally. At the 1st, 4th and 16th weeks after TCDD injection, the 4th lumbar segments of the spinal cord, the same level of spinal ganglia, and the sciatic nerves were taken. They were used for the light and electron microscopic examination and morphometric analysis. The nerve cell bodies of the anterior horn and the spinal ganglia did not show the difference between the TCDD-treated and control groups. Neuronal population of the ganglia of the TCDD-treated group did not differ from that of the control group. Unusually thickened myelin was frequently observed in the TCDD-treated groups, while axonal degeneration was not found in the sciatic nerves of both groups. The cross sectional area of myelin sheaths in the TCDD-treated group of all age was larger than that of the control group. Under the trasmission electron microscope, the myelin of the TCDD-treated group showed that it lost the regular compact arrangement and its lamellar was disrupted. In conclusion, we suggest that TCDD slows down the nerve conduction velocity via the disruption of the myelin structure of the peripheral nerve.

Sensory Neuronal Change after Intravesical Electrical Stimulation in Spinailized Rat

The clinical benefits of intravesical electrical stimulation (IVES) in patients with increased residual urine or reduced bladder capacity have been reported. However, studies on the underlying mechanism of IVES has been limited to the A delta afferent and parasympathetic neurons. This study investigated the changes in the calcitonin gene-related peptide (CGRP), substance P (SP), and nitric oxide synthase (NOS) expression in the thoracolumbar and lumbosacral dorsal root ganglia (DRG) of spinalized rats to determine the effect of IVES on the C fiber afferent nerve. Forty Sprague-Dawley rats were divided into normal controls (n=10); IVES treated normal rats (n=10), spinalized rats (n=10), and IVES treated spinalized rats (n=10). IVES was performed for 2 weeks (5 days a week). IVES was started 3 weeks after spinalization in the spinalized animals. All animals had the DRG removed at the thoracolumbar (T13-L2) and lumbosacral (L5-S1) level. Changes in the CGRP, SP and n-NOS levels at the DRG were measured by western-blot analysis. The relative density of the CGRP and SP following spinalization was significantly higher compared to the controls in both the T13-L2 and L5-S1 DRG. However, IVES in the spinalized rat significantly decreased the relative density of the CGRP and SP compared to the rats with spinalization alone. A significant increase in the relative density of n-NOS was detected in the L5-S1 DRG following spinalization. However, the density of n-NOS was significantly lower after IVES in both the T13-L2 and L5-S1 DRGs. In conclusion, IVES significantly reduced the CGRP, SP and n-NOS levels in the DRG of spinalized rats. CGRP, SP and n-NOS are the main factors that contribute to the hyperexcitability of the micturition reflex after spinal cord injury. These results suggest that the bladder C fiber afferent is also involved in modulating the micturition reflex by IVES.