A Brief Review of Anatomy Education in Korea, Encompassing Its Past, Present, and Future Direction.

Anatomy is a foundational subject in medicine and serves as its language. Hippocrates highlighted its importance, while Herophilus pioneered human dissection, earning him the title of the founder of anatomy. Vesalius later established modern anatomy, which has since evolved historically. In Korea, formal anatomy education for medical training began with the introduction of Western medicine during the late Joseon Dynasty. Before and after the Japanese occupation, anatomy education was conducted in the German style, and after liberation, it was maintained and developed by a small number of domestic anatomists. Medicine in Korea has grown alongside the country's rapid economic and social development. Today, 40 medical colleges produce world-class doctors to provide the best medical care service in the country. However, the societal demand for more doctors is growing in order to proactively address to challenges such as public healthcare issues, essential healthcare provision, regional medical service disparities, and an aging population. This study examines the history, current state, and challenges of anatomy education in Korea, emphasizing the availability of medical educators, support staff, and cadavers for gross anatomy instruction. While variations exist between Seoul and provincial medical colleges, each manages to deliver adequate education under challenging conditions. However, the rapid increase in medical student enrollment threatens to strain existing anatomy education resources, potentially compromising educational quality. To address these concerns, we propose strategies for training qualified gross anatomy educators, ensuring a sustainable cadaver supply, and enhancing infrastructure.

Evaluation and Classification of Supraorbital Nerve Emerging Patterns.

BACKGROUND: Numerous significant variations in the supraorbital nerve (SON) pass through the notches and foramina. During endoscopic forehead lifting, the passage and the location of the nerve against the frontal bone render it susceptible to injury, resulting in diminished or absent sensation in the corresponding location. We attempted to obtain accurate knowledge of the SON emergence routes. METHODS: Data of patients who underwent an endoscopic forehead lift in a plastic surgery clinic between November 2015 and August 2021 were retrospectively analyzed. Deep and superficial branch pathways of SONs were identified and compared according to side and gender. We also classified the nerve patterns into six types. RESULTS: Altogether, 942 patients (1884 SON cases) were evaluated. Out of the patients, 86 patients were male, and 856 were female. The overall mean age was 48.6 (± 13.1) years. In the deep branches, 49% came from the notch, and 51% came from the foramen. In the superficial branches, 67% came from the notch, and 33% of superficial branches came from the foramen. Unlike the deep branch, superficial branches from the notch were significant. Deep and superficial branches of male patients were much more notched than those of female patients. Branches emerged together in 56% and separately in 44% of the cases. CONCLUSION: The absolute number of SON notches was higher than that of SON foramina. This study with the largest number of SON cases will help surgeons understand the variation and course of SON. LEVEL OF EVIDENCE IV: This journal requires that authors 38 assign a level of evidence to each article. For a full 39 description of these Evidence-Based Medicine ratings, 40 please refer to the Table of Contents or the online 41 Instructions to Authors www.springer.com/00266 .

Anatomical Structures to Be Concerned With During Peripherally Inserted Central Catheter Procedures.

BACKGROUND: The central line has been frequently used for drug and nutrition supply and regular blood sampling of patients with chronic diseases. However, this procedure is performed in a highly sensitive area and has several potential complications. Therefore, peripherally inserted central catheters (PICC), which have various advantages, are being extensively used. Although the number of PICC procedures is increasing, the anatomy for safe procedures has not yet been properly established. Therefore, we studied basic anatomical information for safe procedures. METHODS: We used 20 fixed cadavers (40 arms) donated to the Korea University College of Medicine. The mean age was 76.75 years (range, 48-94 years). After dissection of each arm, the distribution pattern of the basilic vein and close structures was recorded, and some important parameters based on bony landmarks were measured. In addition, the number of vein branches (axillary region) and basilic vein diameter were also checked. RESULTS: The mean length from the insertion site to the right atrium was 38.39 ± 2.63 cm (left) and 34.66 ± 3.60 cm (right), and the basilic vein diameter was 4.93 ± 1.18 mm (left) and 4.08 ± 1.49 mm (right). The data showed significant differences between the left and right arms (P < 0.05). The mean distance from the basilic vein to brachial artery was 8.29 ± 2.78 mm in men and 7.81 ± 2.78 mm in women, while the distance to the ulnar nerve was 5.41 ± 1.67 mm in men and 5.52 ± 2.06 mm in women. CONCLUSION: According to these results, the right arm has a shorter distance from the insertion site to the right atrium, and the left arm has a wider vein diameter, which is advantageous for the procedure. In addition, the ulnar nerve and brachial artery were located close to or behind the insertion site. Therefore, special attention is required during the procedure to avoid damaging these important structures.

Optimal placement for needle electromyography of the supinator muscle: Cadaveric studies.

INTRODUCTION/AIMS: The existing methods for needle electromyography are confusing as to which is the safest and most effective. Our aim was to identify the optimal and safest needle electromyographic insertion site in the supinator muscle. METHODS: We performed a two-step cadaveric dissection of the supinator muscle and related neurovascular structures. The study was performed using 18 upper limbs of 9 fresh adult cadavers (step 1) and 14 upper limbs of 7 fresh adult cadavers (step 2). In step 1, an imaginary line connecting the radial head (RH) and midpoint of the dorsal wrist (RW line) was drawn, and the distance from the RH to the point where the RW line and posterior interosseous nerve (PIN) intersect (L_CROSS) was measured on the RW line. In step 2, the needle was inserted 30 mm distal to the RH according to the results of step 1. After injection with India ink, dissection was performed to measure the distance between the needle insertion site and PIN (L_CROSS_Inj) on the RW line. RESULTS: The median L_CROSS was 51.4 (35.5-65.6) mm. Needle insertion spared the PIN in all cases during step 2, and the needle was inserted into the supinator muscle in all cases. The median L_CROSS_Inj was 27.4 (13.2-39.8) mm. DISCUSSION: A safe and accurate needle insertion site for the supinator muscle is approximately 30 to 40 mm distal to the RH along the RW line.

Cerebral Cortex Changes in Basketball Players.

BACKGROUND: Plastic changes to brain structure and function have been reported in elite athletes of various sports. Interestingly, different regions of the brain were engaged according to the type of sports analyzed. Our laboratory reported no difference in total cerebellar volume of basketball players compared to that in the control group using the manual segmentation method. Further detailed analyses showed that elite basketball players had increased volume of the striatum and vermian lobules VI-VII of the cerebellum. We analyzed the brain magnetic resonance imaging (MRI) of basketball players to understand their cerebral cortical plasticity through automatic analysis tools for MRI. METHODS: Brain MRI data were collected from 19 male university basketball players and 20 age-, sex-, and height-matched control groups. In order to understand the changes in the cerebral cortices of basketball players, we employed automated MRI brain analysis techniques, including voxel-based morphometry (VBM) and surface-based morphometry (SBM). RESULTS: VBM showed increased gray and white matter volume in both precentral gyri, paracentral lobules and increased gray matter volume in the right anterior superior temporal gyrus. SBM revealed a left dominant increase in both pericentral gyri. Fractal dimensional analysis showed an increase in the area of both precentral gyri, the left subcallosal gyrus, and the right posterior cingulate gyrus. These results suggest a significant role not only for the primary motor cortex, but also for the cingulate gyrus during basketball. CONCLUSION: Plastic changes of both precentral gyri, the pericentral area, paracentral lobules, and the right superior temporal gyrus were observed in elite basketball players. There was a strong increase of fractal complexity in both precentral gyri and a weak increase in the right posterior cingulate gyrus and left collateral gyrus. In this study, plastic regions linked to functional neuroanatomy were related to the competence required to play basketball.

Complications of Nasopharyngeal Swabs and Safe Procedures for COVID-19 Testing Based on Anatomical Knowledge.

Nasopharyngeal swabs have been widely to prevent the spread of coronavirus disease 2019 (COVID-19). Nasopharyngeal COVID-19 testing is a generally safe and well-tolerated procedure, but numerous complications have been reported in the media. Therefore, the present study aimed to review and document adverse events and suggest procedural references to minimize preventable but often underestimated risks. A total of 27 articles were selected for the review of 842 related documents in PubMed, Embase, and KoreaMed. The complications related to nasopharyngeal COVID-19 testing were reported to be rarely happened, ranging from 0.0012 to 0.026%. Frequently documented adverse events were retained swabs, epistaxis, and cerebrospinal fluid leakage, often associated with high-risk factors, including severe septal deviations, pre-existing skull base defects, and previous sinus or transsphenoidal pituitary surgery. Appropriate techniques based on sufficient anatomical knowledge are mandatory for clinicians to perform nasopharyngeal COVID-19 testing. The nasal floor can be predicted by the line between the nostril and external ear canal. For safe testing, the angle of swab insertion in the nasal passage should remain within 30° of the nasal floor. The swab was gently inserted along the nasal septum just above the nasal floor to the nasopharynx and remained on the nasopharynx for several seconds before removal. Forceful insertion should be attempted, and alternative examinations should be considered, especially in vulnerable patients. In conclusion, patients and clinicians should be aware of rare but possible complications and associated high-risk factors. The suggested procedural pearls enable more comfortable and safe nasopharyngeal COVID-19 testing for both clinicians and patients.

Generation of homogeneous midbrain organoids with in vivo-like cellular composition facilitates neurotoxin-based Parkinson's disease modeling.

Recent studies have demonstrated the generation of midbrain-like organoids (MOs) from human pluripotent stem cells. However, the low efficiency of MO generation and the relatively immature and heterogeneous structures of the MOs hinder the translation of these organoids from the bench to the clinic. Here we describe the robust generation of MOs with homogeneous distribution of midbrain dopaminergic (mDA) neurons. Our MOs contain not only mDA neurons but also other neuronal subtypes as well as functional glial cells, including astrocytes and oligodendrocytes. Furthermore, our MOs exhibit mDA neuron-specific cell death upon treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, indicating that MOs could be a proper human model system for studying the in vivo pathology of Parkinson's disease (PD). Our optimized conditions for producing homogeneous and mature MOs might provide an advanced patient-specific platform for in vitro disease modeling as well as for drug screening for PD.

Adaptations in Anatomy Education during COVID-19.

BACKGROUND: The impact of coronavirus disease 2019 (COVID-19) has profoundly affected education, with most universities changing face-to-face classes to online formats. To adapt to the COVID-19 pandemic situation, we adopted a blended learning approach to anatomy instruction that included online lectures, pre-recorded laboratory dissection videos, and 3D anatomy applications, with condensed offline cadaver dissection. METHODS: We aimed to examine the learning outcomes of a newly adopted anatomy educational approach by 1) comparing academic achievement between the blended learning group (the 2020 class, 108 students) and the traditional classroom learning group (the 2019 class, 104 students), and 2) an online questionnaire survey on student preference on the learning method and reasons of preference. RESULTS: The average anatomy examination scores of the 2020 class, who took online lectures and blended dissection laboratories, were significantly higher than those of the 2019 class, who participated in an offline lecture and dissection laboratories. The questionnaire survey revealed that students preferred online lectures over traditional large group lecture-based teaching because it allowed them to acquire increased self-study time, study according to their individual learning styles, and repeatedly review lecture videos. CONCLUSION: This study suggests that a blended learning approach is an effective method for anatomy learning, and the advantage may result from increased self-directed study through online learning.

Lessons from Cadaver Dissection during the COVID-19 Pandemic.

The rapid increase of the coronavirus disease 2019 pandemic from mid-February 2020 has led the anatomy department of the Korea University College of Medicine to cease the dissection laboratory. However, the hands-on anatomy laboratory experience is paramount to maximizing learning outcomes. In this paper, we share the experiences and lessons learned through the face-to-face cadaveric dissection experience during this disruptive situation. To minimize infection risks, the following strategies were applied: first, students' on-campus attendance was reduced; second, body temperatures and symptoms were checked before entering the laboratory, and personal protective equipment was provided to all participants; and third, a negative pressure air circulation system was used in the dissection room. We suggest that conducting face-to-face cadaveric anatomy dissection is feasible when the daily count of newly infected cases stabilizes, and there is ample provision of safety measures to facilitate hands-on education.

Oral Commissure Lift: A Retrospective Analysis of Complication Rates and Overall Outcomes.

BACKGROUND: Downward-turning oral commissures and sagging mouth corners can present an unfavorable impression. We introduced a new oral commissure lift procedure and investigated its effectiveness and complication rates. METHODS: Patients who underwent oral commissure lift in the plastic surgery clinic between January 2010 and December 2017 were enrolled retrospectively. Pre-and postoperative photographs were evaluated to measure oral commissure angles and analyze surgical complications, including visible scarring, unnatural appearance, and asymmetry. Many patients underwent a oral commissure lift with a simultaneous facelift. To exclude potential bias, we compared angular changes between patients receiving both oral commissure lift and facelift, with those receiving only oral commissure lift. Moreover, oral commissure angles of patients only receiving facelift were also measured. Statistical significance was set at p < 0.05. RESULTS: Oral commissure lift was performed in 51 patients. The mean ages and follow-up periods were 46.7 ± 11.9 years, and 25.2 ± 22.9 months, respectively. The preoperative mean angles of the right and left oral commissures measured - 3.1 ± 4.0° and - 3.4 ± 3.7°, respectively, and postoperative mean angles measured 3.6 ± 3.2° and 3.3 ± 3.5°, respectively. Postoperative changes in oral commissure angles were statistically significant (p < 0.05). The low complication rate included undercorrection in one patient, asymmetry in one patient, and visible scarring in three patients. We found no statistically significant differences in the studies excluding bias. CONCLUSIONS: The new oral commissure lift procedure for correcting sagging oral commissures was simple, safe, and effective with a low complication rate. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A simple morphometric analysis method for dermal microstructure using color thresholding and moments.

BACKGROUND: Proper assessment of dermal collagen fibers by dermatologists and researchers is essential. Histologic evaluation methods have limitations. We present a simple method for measurement of collagen fibers in human skin using Masson's trichrome staining. MATERIALS AND METHODS: Normal skin specimens from a cadaver were processed with Masson's trichrome, which can effectively stain collagen fibers blue with aniline dye. Optical photomicrographs of these slides were analyzed using ImageJ software. Color image processing, a histogram-based function of ImageJ for image segmentation, was performed with color moments thresholding technique. We selected blue areas by adjusting the blue channel to include specific values. The selected areas were highlighted and evaluated. We divided the image into layers of 0.09-mm2 areas from the top to bottom of the dermis. Each area was cropped and evaluated. RESULTS: Quantitative assessment yielded the quantitative size occupied by collagen fibers in an area of 0.09 mm2 . Calculation of the percentage in each area can be used to determine the density of collagen fibers. CONCLUSION: Measurements obtained with our method can be applied to research on dermal collagen fibers. We present a convenient quantitative assessment method for the dermal constituents in Masson's trichrome-stained slides.

An assessment method for dermal structures using cross-polarized light imaging with a green light-emitting diode.

BACKGROUND: Several experimental methods for evaluating dermal structures exist; however, most of these are not used in dermatology clinics because of cost and functional limitations. OBJECTIVE: To propose a simple, non-invasive method for dermal structure evaluation using a green light-emitting diode (LED) with cross-polarized light (CPL) imaging and compare the quality of the images taken using either green or white LED. MATERIALS AND METHODS: Skin specimens were taken from fifteen cadavers. Images were captured using CPL photography with a green or white LED. The Commission International d'Eclairage L*a*b* (CIELAB) values were calculated for each image. The skin specimens were processed and stained with Masson's trichrome to visualize collagen fibers with major image scattering. The images were histologically analyzed, and correlational and regression analyses were performed to determine the relationship between the L* values and histologic measurements. RESULTS: The L* values for the green images were positively correlated with collagen fiber density, reticular collagen bundle diameter, and dermal thickness. They were effective for estimating dermal properties. The L* values for the white images were positively correlated with reticular collagen bundle diameter and dermal thickness. Correlational coefficients for white images were lower than those for green images. In regression analysis, green images showed a higher coefficient of determination (R2 ) for predicting reticular collagen bundle diameter than white images (0.1128 vs. 0.0827). CONCLUSION: Cross-polarized light imaging with a green LED is a simple, non-invasive method for evaluating dermal structures. The use of a green LED was also more effective for image analysis.

A cadaveric study for the volar needle approach to the pronator quadratus using the palmaris longus tendon landmark.

INTRODUCTION: Our aim in this work was to determine the safety and accuracy of the volar approach to the pronator quadratus (PQ) through cadaver dissection. METHODS: Twenty upper limbs from 10 fresh cadavers were investigated. At the level 3 cm proximal to the ulnar styloid process (USP), a needle was inserted just medial to the palmaris longus (PL) tendon. Distances of the median nerve (MN) and ulnar artery (UA) from the needle insertion point (IP) were measured using ultrasonography and cadaver dissection. RESULTS: The PQ was located at a depth of 10.8-19.9 mm from the skin and had a median thickness of 9.1 mm, measured 3 cm proximal to the USP. The median distances of the MN and UA from the IP were 7.6 and 13.4 mm, respectively. DISCUSSION: A needle insertion for the volar approach to the PQ was safe at 3 cm proximal to the USP, just medial to the PL tendon.

Hypomyelination and cognitive impairment in mice lacking CD133 (Prominin-1).

The CD133 antigen, also known as prominin-1, is a glycoprotein that specifically localizes to plasma membrane protrusions. The precise function of CD133 remains unknown, but it is expressed in various progenitor cells including those derived from the neural and hematopoietic system, as well as different tissues. In the adult mouse brain, CD133 is highly expressed in white matter. Here, we performed immunohistochemical staining and electron microscopy to demonstrate that mice lacking CD133 (CD133-/-) exhibit decreased myelin in the corpus callosum, the largest white matter tract in the brain. Hypomyelination in CD133-/- mice was associated with fewer oligodendrocyte progenitor cells and mature oligodendrocytes. Behavioral analyses revealed that significantly impaired object recognition memory and altered Y-maze performance by CD133-/- mice compared with wild-type mice, suggesting perturbed cognitive performance. These results suggest that CD133 regulates myelination and understanding the underlying molecular mechanisms may guide the development of novel therapeutic strategies for diseases characterized by myelin deficiency.

Changes in intracranial volume and cranial shape in modern Koreans over four decades.

OBJECTIVES: This study investigated whether there was any secular change in cranial vault morphology among Koreans born between the 1930s and 1970s, a period of dramatic shift in Korea's socioeconomic conditions. MATERIALS AND METHODS: Using three-dimensional MRI volumetry, we obtained the intracranial volume (ICV) and craniometric measurements of 115 healthy Koreans: 58 individuals (32 males and 26 females) born in the 1930s (1926-1936) and 57 (28 males and 29 females) born in the 1970s (1972-1979). RESULTS: The intracranial volume of males was 1502.3 ± 110.3 cm3 for the 1930s group and 1594.1 ± 99.5 cm3 for the 1970s group, and for females, it was 1336.0 ± 53.0 cm3 for the 1930s group and 1425.9 ± 79.6 cm3 for the 1970s group. On average, ICV increased by 94 cm3 in males and by 90 cm3 in females. Cranial measurements for the 1970s group were significantly larger than the 1930s group for both sexes except in female cranial length. Each measurement was significantly correlated with ICV [cranial height (R = 0.720), breadth (R = 0.706), and length (R = 0.531)]. The cephalic index decreased from 0.846 to 0.828 in males, indicating the cranium became narrower relative to the cranial length. In females, the cephalic index increased from 0.831 to 0.850. Sex and birthyear were marginally interrelated in cephalic indices. DISCUSSION: From the 1930s to 1970s, the Korean Peninsula experienced important historical shifts, and we speculate that the consequent shift in socioeconomic status is the most likely factor responsible for Koreans' cranial vault remodeling.

Emotional experiences of medical students during cadaver dissection and the role of memorial ceremonies: a qualitative study.

BACKGROUND: It has been well reported that the emotional experiences of medical students in the gross anatomy laboratory could have significant impacts on their professional identity formation. This qualitative study aimed to investigate students' emotions towards cadaver dissection and the educational role of memorial ceremonies. METHODS: A total of 37 students from eight teams were recruited in the team-based dissection course during two consecutive academic years (2016 and 2017) at one medical school. In focus group interviews, students were encouraged to express and discuss their emotions regarding cadaver dissection and memorial ceremonies. RESULTS: The participants described their apprehension and anxiety during their first encounter with cadavers that diminished through gradual exposure. Unfortunately, their positive emotions such as gratitude and responsibility also tended to decline under the pressure of excessive workloads and frequent examinations. Memorial ceremonies, including not only large-scale events but also daily rituals, had educational effects that they prevented the decline of students' responsibility and respect during the dissection course. CONCLUSION: Educators should assist medical students in overcoming their initial distress and maintaining respectful attitudes throughout the dissection course. Memorial ceremonies can be effective educational tools for fostering appropriate attitudes and ethical practice in the gross anatomy laboratory.

Nobiletin attenuates neurotoxic mitochondrial calcium overload through K+ influx and ΔΨm across mitochondrial inner membrane.

Mitochondrial calcium overload is a crucial event in determining the fate of neuronal cell survival and death, implicated in pathogenesis of neurodegenerative diseases. One of the driving forces of calcium influx into mitochondria is mitochondria membrane potential (ΔΨm). Therefore, pharmacological manipulation of ΔΨm can be a promising strategy to prevent neuronal cell death against brain insults. Based on these issues, we investigated here whether nobiletin, a Citrus polymethoxylated flavone, prevents neurotoxic neuronal calcium overload and cell death via regulating basal ΔΨm against neuronal insult in primary cortical neurons and pure brain mitochondria isolated from rat cortices. Results demonstrated that nobiletin treatment significantly increased cell viability against glutamate toxicity (100 µM, 20 min) in primary cortical neurons. Real-time imaging-based fluorometry data reveal that nobiletin evokes partial mitochondrial depolarization in these neurons. Nobiletin markedly attenuated mitochondrial calcium overload and reactive oxygen species (ROS) generation in glutamate (100 µM)-stimulated cortical neurons and isolated pure mitochondria exposed to high concentration of Ca2+ (5 µM). Nobiletin-induced partial mitochondrial depolarization in intact neurons was confirmed in isolated brain mitochondria using a fluorescence microplate reader. Nobiletin effects on basal ΔΨm were completely abolished in K+-free medium on pure isolated mitochondria. Taken together, results demonstrate that K+ influx into mitochondria is critically involved in partial mitochondrial depolarization-related neuroprotective effect of nobiletin. Nobiletin-induced mitochondrial K+ influx is probably mediated, at least in part, by activation of mitochondrial K+ channels. However, further detailed studies should be conducted to determine exact molecular targets of nobiletin in mitochondria.

Axin is expressed in mitochondria and suppresses mitochondrial ATP synthesis in HeLa cells.

Many recent studies have revealed that axin is involved in numerous cellular functions beyond the negative regulation of ß-catenin-dependent Wnt signaling. Previously, an association of ectopic axin with mitochondria was observed. In an effort to investigate the relationship between axin and mitochondria, we found that axin expression suppressed cellular ATP production, which was more apparent as axin expression levels increased. Also, mitochondrial expression of axin was observed using two axin-expressing HeLa cell models: doxycycline-inducible ectopic axin expression (HeLa-axin) and axin expression enhanced by long-term treatment with XAV939 (HeLa-XAV). In biochemical analysis, axin is associated with oxidative phosphorylation (OXPHOS) complex IV and is involved in defects in the assembly of complex IV-containing supercomplexes. Functionally, axin expression reduced the activity of OXPHOS complex IV and the oxygen consumption rate (OCR), suggesting axin-mediated mitochondrial dysfunction. Subsequent studies using various inhibitors of Wnt signaling showed that the reduction in cellular ATP levels was weaker in cases of ICAT protein expression and treatment with iCRT3 or NSC668036 compared with XAV939 treatment, suggesting that XAV939 treatment affects ATP synthesis in addition to suppressing Wnt signaling activity. Axin-mediated regulation of mitochondrial function may be an additional mechanism to Wnt signaling for regulation of cell growth.

A Method of Radial Nerve Length Measurement Based on Cadaveric Investigation.

OBJECTIVE: To determine the most reliable method to measure the length of the radial nerve during a nerve conduction study (NCS). DESIGN: Cadaveric investigation. SETTING: A practical anatomy research laboratory in a university. PARTICIPANTS: Fresh cadavers (N=10), with 1 cadaver for study design and 9 for data. INTERVENTIONS: Design of measurement methods using cadaver dissection and comparison of the measured values to the true length in 18 arms of 9 cadavers. MAIN OUTCOME MEASURES: Four points (A, B, C, D) were determined: (A) proximal stimulation point in NCS; (B) point at the elbow crease; (C) point in the midforearm; and (D) distal stimulation point 5cm above the extensor indicis. The true length of the radial nerve between the stimulus points (points A and D) in NCS was compared with the measured values by summation of the straight line segments between those points with various combinations. The difference in root mean square error (RMSE) of the distance measured by each method compared with the true length was calculated to determine the best measurement method. RESULTS: The closest distance to the true length (28.7±2.8cm) in the cadaveric investigation was obtained using the summation of straight line segments between points A, B, and D (A-B-D, RMSE=.72cm), followed by the A-B-C-D distance (RMSE=.87cm) and the A-D distance (RMSE=1.38cm) methods, in sequence. The former 2 distance measurements were relatively closer to the true length than the latter measurement method. CONCLUSIONS: Multiple segmentation measurement methods reflected the course of the radial nerve better than a single linear measurement method. We suggest that the distance measured using a stopover point near the lateral epicondyle between 2 stimulus points (A-B-D distance) is closer to the true length of the nerve.

Changes in ankle joint motion after Supramalleolar osteotomy: a cadaveric model.

BACKGROUND: Malalignment of the ankle joint has been found after trauma, by neurological disorders, genetic predisposition and other unidentified factors, and results in asymmetrical joint loading. For a medial open wedge supramalleolar osteotomy(SMO), there are some debates as to whether concurrent fibular osteotomy should be performed. We assessed the changes in motion of ankle joint and plantar pressure after supramalleolar osteotomy without fibular osteotomy. METHODS: Ten lower leg specimens below the knee were prepared from fresh-frozen human cadavers. They were harvested from five males (10 ankles)whose average age was 70 years. We assessed the motion of ankle joint as well as plantar pressure for SS(supra-syndesmotic) SMO and IS(intra-syndesmotic) SMO. After the osteotomy, each specimen was subjected to axial compression from 20 N preload to 350 N representing half-body weight. For the measurement of the motion of ankle joint, the changes in gap and point, angles in ankle joint were measured. The plantar pressure were also recorded using TekScan sensors. RESULTS: The changes in the various gap, point, and angles movements on SS-SMO and IS-SMO showed no statistically significant differences between the two groups. Regarding the shift of plantar center of force (COF) were noted in the anterolateral direction, but not statistically significant. CONCLUSIONS: SS-SMO and IS-SMO with intact fibula showed similar biomechanical effect on the ankle joint. We propose that IS-SMO should be considered carefully for the treatment of osteoarthrosis when fibular osteotomy is not performed because lateral cortex fracture was less likely using the intrasyndesmosis plane because of soft tissue support.