Risk of Axillary Nerve Injury With Medial Support Screws in Intramedullary Nails: An Anatomical Study.

BACKGROUND: In recent years, intramedullary nails with medial support screws for proximal humeral fractures have become available. Although these devices have a potential risk of iatrogenic axillary nerve injury, no studies have investigated the anatomical relationship between the medial support screws in the modern intramedullary nail and the axillary nerve. This study aimed to clarify the anatomical relationship between the medial support screws in the intramedullary nail and the axillary nerve. MATERIALS AND METHODS: In total, 29 cadaveric shoulders (mean age: 82.6 years old (range: 61-105); 15 males and 14 females) were included in this study. Shoulders within whole-body cadavers were used in all cases. A single proximal humeral nail with medial support screws (ARISTO Proximal Humeral Nail; MDM, Tokyo, Japan) was used. The distance of each medial support screw from the axillary nerve and its branches was measured. RESULTS: In two (6.90%) of 29 shoulders, the axillary nerves came into contact with the medial support screws. In the remaining 27 of 29 shoulders (93.1%), the nerves were located proximal to the medial support screws. CONCLUSION: Medial support screws in proximal humeral fracture nails had the potential to injure the axillary nerve and its branches.

[Study on the consistency between CBCT image features of sphenopalatine foramen and those seen in nasal endoscopy].

Objective:To study the clinical anatomy of the sphenopalatine foramina by dissecting the sphenopalatine foramina during Vidian nerve branch neurotomy. The anatomy and CBCT images of sphenopalatine foramen were analyzed to facilitate the navigational of clinical operation using CBCT images. Methods:From October 2017 to September 2023, 84 cases（168 sides） of Vidian nerve branch neurotomy in our department were collected. The clinical summary was made according to the anatomy of sphenopalatine foramen during the operation. Preoperative CBCT imaging findings of the sphenopalatine foramina were also studied. Results:The clinical anatomy of sphenopalatine foramen could be divided into four types: middle meatus type（1.19%）, trans-meatus type（62.29%）, superior meatus type（33.33%） and double foramen type（1.19%）. The incidence of ethmoidal ridge was 98.81%. The distance from sphenopalatine foramina to posterior nasal canal were（14.63±2.66） mm to left and（14.65±2.63） mm to right, The position Angle ∠a of lower margin of sphenopalatine foramina were（62.36±10.05）° to left and（61.51±11.82）° to right, respectively. Axial CT images can be used to divide the sphenopalatine foramen into five levels: the upper edge of the sphenopalatine foramen level, the Vidian nerve level, the basal plate interaction level, the lower edge of the sphenopalatine foramen level and the pterygopalatine canal level. The agreement between endoscopic anatomy of sphenopalatine foramen and imaging navigation was 100%. Conclusion:The sphenopalatine foramina exhibit various anatomical types. The preoperative navigational CBCT reading can effectively identify the type of sphenopalatine foramina, guide the choice of surgical method, and help avoid serious complications. This has significant clinical application value.

Systematic review on the frequency of occurrence in nerve branches and the side of the face involved in trigeminal neuralgia and its clinical implication.

Purpose: The purpose of this systematic review is to answer the focused question, "What is the commonly affected nerve branch and the side of the face involved in trigeminal neuralgia?" Types of studies reviewed: This systematic review included studies reporting commonly affected trigeminal nerve branches and the side of the face involved in trigeminal neuralgia. To find the potential studies published, the authors utilized specific search databases such as PubMed, and Google scholar. Results: Among 132 published studies, the authors selected only 11 to be included for this systematic review. The sample size ranged from 50 to 43,518 study subjects. This review identified that the mandibular branches of the trigeminal nerve were the most affected, followed by the maxillary branch. The review also identified that the right side of the face was predominantly affected. Conclusion and practical implications: The authors of this review identified a higher occurrence of trigeminal neuralgia in the mandibular division of the nerve, commonly affected on the right side of the face. Further prospective-based research and meta-analysis are required to validate the commonly occurring trigeminal nerve branch and sidedness of the face involved with its clinical implications in trigeminal neuralgia.

[Effectiveness of finger reconstruction using nail flap anastomosing nerve branch of the first toe nail bed].

Objective: To investigate the effectiveness of finger reconstruction using nail flap anastomosing the nerve branch of the first toe nail bed. Methods: Between January 2016 and December 2022, 18 patients (18 fingers) with thumb or finger nail bed defects were admitted. There were 12 males and 6 females, with an average age of 32 years (range, 19-42 years). Four cases were finger tip tissue damage caused by machine compression, and 4 cases were distal tissue necrosis after finger replantation. There were 9 cases of thumb injury, 3 cases of index finger injury, 5 cases of middle finger injury, and 1 case of ring finger injury. There were 11 cases of distal nail damage and 7 cases of distal nail root (including nail root) damage. The time from injury to admission was 1-5 hours, with an average of 2 hours. After debridement and anti-infection treatment for 5-7 days, the wounds in size of 1 cm×1 cm to 4 cm×3 cm were reconstructed by using nail flaps anastomosing the nerve branches of the first toe nail bed. The size of the nail flaps ranged from 1.5 cm×1.5 cm to 4.5 cm×3.5 cm. The donor sites were repaired with the flaps in 16 cases and skin graft in 2 cases. Results: All nail flaps, flaps, and skin grafts survived after operation and the wounds healed by first intention. All patients were followed up 6-12 months (mean, 10 months). The nails of 18 cases were all grown, in which 16 cases had smooth nails with satisfactory appearances, 1 case had uneven nails, and 1 case had obvious scar hyperplasia around the suture opening. At 6 months after operation, the two-point discrimination of the skin flap was 4-8 mm (mean, 6 mm). Meanwhile, the skin grafts and flaps at the donor sites regained protective sensation, good abrasion resistance, and had no negative effect upon walking and wearing shoes. Conclusion: The application of a nail flap that anastomoses the nerve branch of the first toe nail bed for finger reconstruction has minimal damage and can achieve good nail bed repair results.

Loss of Corneal Nerves and Corneal Haze in Patients with Fuchs' Endothelial Corneal Dystrophy with the Transcription Factor 4 Gene Trinucleotide Repeat Expansion.

Objective: Seventy percent of Fuchs' endothelial corneal dystrophy (FECD) cases are caused by an intronic trinucleotide repeat expansion in the transcription factor 4 gene (TCF4). The objective of this study was to characterize the corneal subbasal nerve plexus and corneal haze in patients with FECD with (RE+) and without the trinucleotide repeat expansion (RE-) and to assess the correlation of these parameters with disease severity. Design: Cross-sectional, single-center study. Participants: Fifty-two eyes of 29 subjects with a modified Krachmer grade of FECD severity from 1 to 6 were included in the study. Fifteen of the 29 subjects carried an expanded TCF4 allele length of ≥ 40 cytosine-thymine-guanine repeats (RE+). Main Outcomes Measures: In vivo confocal microscopy assessments of corneal nerve fiber length (CNFL), corneal nerve branch density, corneal nerve fiber density (CNFD), and anterior corneal stromal backscatter (haze); Scheimpflug tomography densitometry measurements of haze in anterior, central, and posterior corneal layers. Results: Using confocal microscopy, we detected a negative correlation between FECD severity and both CNFL and CNFD in the eyes of RE+ subjects (Spearman ρ = -0.45, P = 0.029 and ρ = -0.62, P = 0.0015, respectively) but not in the eyes of RE- subjects. Additionally, CNFD negatively correlated with the repeat length of the expanded allele in the RE+ subjects (Spearman ρ = -0.42, P = 0.038). We found a positive correlation between anterior stromal backscatter and severity in both the RE+ and RE- groups (ρ = 0.60, P = 0.0023 and ρ = 0.44, P = 0.024, respectively). The anterior, central, and posterior Scheimpflug densitometry measurements also positively correlated with severity in both the RE+ and RE- groups (P = 5.5 × 10-5, 2.5 × 10-4, and 2.9 × 10-4, respectively, after adjusting for the expansion status in a pooled analysis. However, for patients with severe FECD (Krachmer grades 5 and 6), the posterior densitometry measurements were higher in the RE+ group than in the RE- group (P < 0.05). Conclusions: Loss of corneal nerves in FECD supports the classification of the TCF4 trinucleotide repeat expansion disorder as a neurodegenerative disease. Haze in the anterior, central, and posterior cornea correlate with severity, irrespective of the genotype. Quantitative assessments of corneal nerves and corneal haze may be useful to gauge and monitor FECD disease severity in RE+ patients.

In vivo confocal microscopy of corneal nerve fiber damage in early course of multiple sclerosis.

PURPOSE: To evaluate the corneal nerve fiber morphology in patients with multiple sclerosis (MS) by in vivo corneal confocal microscopy (CCM). METHODS: Retinal nerve fiber layer thickness (RNFLT), central macular thickness (CMT), corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD) and corneal nerve fiber tortuosity (CNFT) were measured. Correlation of corneal nerve findings with duration and clinical severity of MS was calculated. RESULTS: CNFL (9.50 ± 0.60 vs. 11.20 ± 0.57 mm/mm2, P = 0.046) and CNBD (57.46 ± 5.04 vs. 77.65 ± 3.41 no/mm2, P = 0.001) were significantly lower with no significant difference in CNFD (21.24 ± 1.20 vs. 23.62 ± 0.95 no/mm2, P = 0.125), CNFT (2.00 ± 0.15 vs. 1.73 ± 0.12, P = 0.180), CMT (269.57 ± 12.53 vs. 271.10 ± 18.84 µm, P = 0.716) or RNFLT (102.82 ± 6.98 vs. 105.33 ± 12.70 µm, P = 0.351) between patients with RRMS compared to controls. There was no significant correlation between CCM parameters with EDSS and duration of disease in MS patients. CONCLUSION: The current study demonstrated that a decrease in CNFL, CNFD and CNBD in CCM analysis in the early course of MS.

Effectiveness of finger reconstruction using nail flap anastomosing nerve branch of the first toe nail bed / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effectiveness of finger reconstruction using nail flap anastomosing the nerve branch of the first toe nail bed.@*METHODS@#Between January 2016 and December 2022, 18 patients (18 fingers) with thumb or finger nail bed defects were admitted. There were 12 males and 6 females, with an average age of 32 years (range, 19-42 years). Four cases were finger tip tissue damage caused by machine compression, and 4 cases were distal tissue necrosis after finger replantation. There were 9 cases of thumb injury, 3 cases of index finger injury, 5 cases of middle finger injury, and 1 case of ring finger injury. There were 11 cases of distal nail damage and 7 cases of distal nail root (including nail root) damage. The time from injury to admission was 1-5 hours, with an average of 2 hours. After debridement and anti-infection treatment for 5-7 days, the wounds in size of 1 cm×1 cm to 4 cm×3 cm were reconstructed by using nail flaps anastomosing the nerve branches of the first toe nail bed. The size of the nail flaps ranged from 1.5 cm×1.5 cm to 4.5 cm×3.5 cm. The donor sites were repaired with the flaps in 16 cases and skin graft in 2 cases.@*RESULTS@#All nail flaps, flaps, and skin grafts survived after operation and the wounds healed by first intention. All patients were followed up 6-12 months (mean, 10 months). The nails of 18 cases were all grown, in which 16 cases had smooth nails with satisfactory appearances, 1 case had uneven nails, and 1 case had obvious scar hyperplasia around the suture opening. At 6 months after operation, the two-point discrimination of the skin flap was 4-8 mm (mean, 6 mm). Meanwhile, the skin grafts and flaps at the donor sites regained protective sensation, good abrasion resistance, and had no negative effect upon walking and wearing shoes.@*CONCLUSION@#The application of a nail flap that anastomoses the nerve branch of the first toe nail bed for finger reconstruction has minimal damage and can achieve good nail bed repair results.

Iatrogenic sciatic nerve injury due to cerclage wiring for proximal periprosthetic femoral fracture: A rare case report.

Cerclage wiring is used to reinforce the stability of fractures and optimize plate fixations for femoral fractures such as periprosthetic fractures. However, cerclage wiring requires attention to neurovascular structures to prevent injuries. We have presented a case of iatrogenic sciatic nerve injury after osteosynthesis with cerclage wiring. A 71-year-old woman underwent osteosynthesis with cerclage wiring for a proximal periprosthetic femoral fracture. Immediately after the operation, the patient developed motor and sensory disorders, particularly in the sciatic nerve area, leading to a suspicion of nerve injury. Consequently, reoperation showed that the right sciatic nerve was strangulated by the cerclage wire, but the nerve was functional. Since the sciatic nerve was partially continuous and retained sensation to some extent, strangulation release was performed. Subsequently, both sensory and motor disorders improved. This case suggests that attention should be given to not only the blood vessels in the anterior region but also the sciatic nerve in the posterior region when performing cerclage wiring for femoral fractures.

Caracterización de la comunicación ulnar-mediano palmar profunda en una muestra con material cadavérico / Characterization of ulnar-median deep palmar communication in a sample with cadaveric material

RESUMEN: La comunicación Ulnar-Mediano Palmar Profunda (CUMPP) es la conexión entre la rama profunda del nervio ulnar (NU) y la rama del nervio mediano (NM) que inerva a los músculos tenares como la cabeza superficial del flexor corto del pulgar. Son escasos los trabajos que se ocupan de esta rama comunicante, y su prevalencia es reportada con una amplia variabilidad, en un rango del 16-77 %. Este estudio no probabilístico, descriptivo, transversal, evaluó la frecuencia y características morfológicas de la CUMPP en 106 manos de especímenes cadavéricos frescos no reclamados, a quienes se les practicó necropsia en el Instituto de Medicina Legal de Bucaramanga (Colombia). Se observó rama comunicante CUMPP en 39 especímenes (50,2 %), de los cuales 12 (44,5 %) fueron bilate- rales, 15 (55,6 %) unilaterales, con predominio unilateral derecho para 9 casos (60 %), sobre el izquierdo de tan solo 6 casos (40 %). No se evidenciaron diferencias estadísticamente significativas con relación al lado de presentación (P=0,223). En 21 especímenes (54 %) se observó el tipo IV; mientras que el tipo I fue encontrado en 4 casos (10 %). El promedio de la longitud de la rama comunicante fue de 24,67 DE 6,46 mm; mientras que la distancia del punto proximal de la CUMPP al surco distal del carpo fue de 41,4 DE 2,6 mm. Nuestros hallazgos no son concordantes con lo reportado en la mayoría de estudios previos. Diversos factores como el tamaño de las muestras, las diferentes metodologías de medición y las expresiones fenotípicas de cada grupo de población evaluado, pueden explicar la variabilidad de la CUMPP.

SUMMARY: Deep Palmar Ulnar-Medium Communication (DPUMC) is the connection between the deep branch of the ulnar nerve (UN) and the median nerve (MN) branch, that innervates the thenar muscles as the superficial head of the short flexor of the thumb. Few studies dealing with this communicating branch, and its prevalence is reported with a wide variability in the range of 16-77 %. This non-probabilistic, descriptive, cross-sectional study; evaluated the frequency and morphological characteristics of DPUMC in 106 hands of fresh unclaimed cadaveric specimens, that underwent necropsy at the Institute of Legal Medicine of Bucaramanga (Colombia). DPUMC communicating branch was observed in 39 specimens (50.2 %), of which 12 (44.5 %) were bilateral, 15 (55.6 %) unilateral, with right unilateral predominance for 9 cases (60 %), on the left of only 6 cases (40 %). There were no statistically significant differences in relation to the presentation side (P = 0.223). In 21 specimens (54%), type IV was observed; while type I was found in 4 cases (10%). The average length of the communicating branch was 24.67 SD 6.46 mm; while the distance from the proximal point of the DPUMC to the distal carpal groove was 41.4 SD 2.6 mm. Our findings are not consistent with those reported in most previous studies. Various factors such as sample size, different measurement methodologies and phenotypic expressions of each population group evaluated can explain the variability of the DPUMC.

Corneal confocal microscopy as a non-invasive test to assess diabetic peripheral neuropathy.

OBJECTIVE: To evaluate the efficacy of corneal confocal microscopy (CCM) as a non-invasive test to assess diabetic peripheral neuropathy in Chinese patients diagnosed with type 2 diabetes. RESEARCH DESIGN AND METHODS: Diabetic distal symmetric polyneuropathy (DSPN) and its severity degrees were assessed based on the modified Toronto diagnostic criteria in 128 patients with type 2 diabetes (No DSPN [n = 49], mild DSPN [n = 43], moderate-to-severe DSPN [n = 36]) and 24 age-matched controls. CCM was also examined in all enrolled subjects. Corneal nerve fiber length (CNFL), corneal nerve branch density (CNBD) and corneal nerve fiber density (CNFD) were analyzed by Fiji imaging analysis software. The efficacy of CCM as a non-invasive test to assess diabetic peripheral neuropathy was determined. RESULTS: CNFL was 17.99 ±â€¯0.66, 15.82 ±â€¯0.64, 14.98 ±â€¯0.63, and 12.49 ±â€¯0.93 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNFL in type 2 diabetes patients with no, mild, and moderate-to-severe DSPN demonstrated a significant reduction than in healthy controls (P = .012, .003 and <.001, respectively). CNFL in patients with moderate-to-severe DSPN was significantly shorter than in patients with no or mild DSPN (P < .001 and .004, respectively). CNBD was 41.48 ±â€¯3.35, 33.02 ±â€¯2.50, 30.91 ±â€¯2.33, and 18.00 ±â€¯2.33 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNBD in healthy control was significantly higher than in type 2 diabetes patients with no, mild, and moderate-to-severe DSPN (P = .036, 0.016 and < .001, respectively). CNBD in patients with moderate-to-severe DSPN was significantly lower than in patients with no or mild DSPN (P < .001 for both). CNFD was 35.32 ±â€¯1.18, 35.68 ±â€¯1.10, 34.54 ±â€¯1.12, and 32.28 ±â€¯1.76 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNFD did not differ among the four groups. In an analysis that divided CNFL, CNFD and CNBD into quartiles, there were no significant differences in electromyography findings and vibration perception threshold among the 4 groups; however, significant differences were seen in the positive distribution of temperature perception measurements following CNFL and CNBD stratification (P = .001 and < .001, respectively). CONCLUSION: CCM might be a non-invasive method for detecting DSPN and its severity degree in Chinese patients diagnosed with type 2 diabetes.

Orbital fat volume in the inferolateral quadrant in Japanese: a guide for orbital fat decompression without injury to the oculomotor nerve.

PURPOSE: The inferior oblique muscle branch of the oculomotor nerve is susceptible to injury during orbital fat removal from the inferolateral quadrant of the orbit. Understanding the amount of removable orbital fat volume in this quadrant may be helpful in achieving maximum fat decompression without causing nerve injury. The aim of this study was to calculate the orbital fat volume in the inferolateral quadrant using computed tomographic (CT) images. METHODS: In this retrospective, observational study, contiguous 1-mm coronal CT images were obtained from 53 sides (30 patients). The cross-sectional areas of the orbital fat in the inferolateral quadrant were measured from the level just behind the inferior oblique muscle to the orbital apex. The cross-sectional areas reached the inferior oblique muscle branch medially, the lateral orbital wall laterally, the inferior edge of the lateral rectus muscle superiorly, and the orbital floor inferiorly. An integrated value between the cross-sectional areas and the CT slice thickness was calculated. RESULTS: The mean orbital fat volume in the inferolateral quadrant was 3.9 ± 1.4 mL (range: 1.3-7.0 mL). Multiple regression analysis demonstrated a significant relationship between orbital fat volume and Hertel exophthalmometry measurement (adjusted r 2 = 0.101; P = 0.012), although the thickness of the lateral and inferior recti muscles was deleted from the regression equation by stepwise process. CONCLUSIONS: The orbital fat volume in the inferolateral quadrant can serve as a guide for orbital fat removal without causing injury to the inferior oblique muscle nerve branch.

A cadaveric study of surgical landmarks for retrograde parotidectomy.

PURPOSE: Retrograde parotidectomy is employed in situations where tumors or scar tissue obscure the facial nerve trunk, making anterograde parotidectomy hazardous. Hence, the reliability of anatomical landmarks in retrograde parotidectomy is of equal practical importance. METHODS: Distances from soft tissue and osseous landmarks to the corresponding peripheral branches of the facial nerve were measured in 41 half-head specimens. The distances were from: i) the zygomatic arch (Z) to the buccal branch (B); ii) the retromandibular vein (RMV) to the marginal mandibular branch (MM); and iii) the angle of the mandible (A) to MM. These distances were compared in left vs, right sides, male vs. female groups, occlusal vs. nonocclusal sides. RESULTS: No statistically significant differences were found in any of the three distances between all groups compared, amongst which, the mean distances from A to MM were the shortest and least variable (Male = 8.9 ± 3.0 mm vs. Female = 6.8 ± 3.5 mm; Left = 7.3 ± 2.8 mm vs. Right = 8.8 ± 3.9 mm; Occlusal = 8.6 ± 3.5 mm vs. Nonocclusal = 7.8 ± 3.4 mm). CONCLUSION: The findings indicate that all three landmarks are useful for surgeons to locate the facial nerve branches during retrograde parotidectomy. Since all three landmarks were consistent indicators for the corresponding facial nerve branches, the surgeon has more than one option should one landmark be obscured by tumors. The optimal landmark is the distance from A to MM because it is shortest and most reliable, followed by RMV to MM, and Z to B.

Teres minor innervation and injection site / Inervación y sitio de inyección del músculo redondo menor

The aim of this study was to elucidate the injection point on the teres minor (TM) for effective injection. Thirty-two specimens from 16 adult Korean cadavers (10 males and 6 females, age ranging from 42 to 102 years) were used in the study. The reference line between the inferior point on the inferior angle of the scapula (IA) and the most prominent point on the acromial angle of the scapula (AA) on the surface were identified. The measurements expressed the two above-mentioned parameters as X and Y coordinates in relation to the reference line. The X coordinate was located at 128.1±10.4 mm (78.1±5.7 %) and the Y coordinate was located at 25.3±7.6 mm (15.5±4.8 %). The recommended site according to this can be used for injections in patients with TM stiffness.

El objetivo fue determinar el punto de inyección en el músculo redondo menor (MRM) para llevar a cabo una correcta inyección. Se utilizaron 32 muestras correspondientes a 16 cadáveres adultos coreanos (10 hombres y 6 mujeres, entre 42 a 102 años de edad). Se identificó en la superficie la línea de referencia entre el punto inferior en el ángulo inferior de la escápula (AI) y el punto más prominente en el ángulo acromial de la escápula (AA). Las mediciones expresaron los dos parámetros mencionados anteriormente como coordenadas X e Y en relación con la línea de referencia. La coordenada X se encuentra a 128,1±10,4 mm (78,1±5,7 %) y la coordenada Y estaba situada a 25,3±7,6 mm (15,5±4,8 %). El sitio recomendado de acuerdo a estos resultados se puede usar para preparaciones inyectables en pacientes con rigidez del MRM.

Motor branch biopsy of the pronator teres muscle in a patient with painful forearm neuropathy.

Histological evaluation of a peripheral nerve is often the final diagnostic work-up for a neuropathy of unknown origin, and a distal sensory nerve is usually biopsied. Here, we report the case of a female patient with painful unilateral neuropathy in the upper arm. According to the histological evaluation of the pronator teres motor branch, vasculitis seemed to be the most probable cause of the condition, and steroid therapy improved the patients' symptoms. A biopsy of the motor branch of the pronator teres muscle nerve may be considered a valuable diagnostic option in selected cases with neuropathy affecting the upper limb, when performed in cooperation with neurologists and orthopedic surgeons.

Adult motor axons preferentially reinnervate predegenerated muscle nerve.

Preferential motor reinnervation (PMR) is the tendency for motor axons regenerating after repair of mixed nerve to reinnervate muscle nerve and/or muscle rather than cutaneous nerve or skin. PMR may occur in response to the peripheral nerve pathway alone in juvenile rats (Brushart, 1993; Redett et al., 2005), yet the ability to identify and respond to specific pathway markers is reportedly lost in adults (Uschold et al., 2007). The experiments reported here evaluate the relative roles of pathway and end organ in the genesis of PMR in adult rats. Fresh and 2-week predegenerated femoral nerve grafts were transferred in correct or reversed alignment to replace the femoral nerves of previously unoperated Lewis rats. After 8 weeks of regeneration the motoneurons projecting through the grafts to recipient femoral cutaneous and muscle branches and their adjacent end organs were identified by retrograde labeling. Motoneuron counts were subjected to Poisson regression analysis to determine the relative roles of pathway and end organ identity in generating PMR. Transfer of fresh grafts did not result in PMR, whereas substantial PMR was observed when predegenerated grafts were used. Similarly, the pathway through which motoneurons reached the muscle had a significant impact on PMR when grafts were predegenerated, but not when they were fresh. Comparison of the relative roles of pathway and end organ in generating PMR revealed that neither could be shown to be more important than the other. These experiments demonstrate unequivocally that adult muscle nerve and cutaneous nerve differ in qualities that can be detected by regenerating adult motoneurons and that can modify their subsequent behavior. They also reveal that two weeks of Wallerian degeneration modify the environment in the graft from one that provides no modality-specific cues for motor neurons to one that actively promotes PMR.

Auriculotemporal and greater auricular nerve blocks have roles in patients with Ramsay Hunt syndrome with trigeminal nerve involvement: A report of two cases

Ramsay Hunt syndrome (RHS) refers to herpes zoster infection of the geniculate ganglion of the facial nerve. Cases complicated by multicranial nerve involvement in the process of reactivation of the virus, which are known to show virulent clinical course and worse prognosis, are not common in literature as in practice, and there has been only one reported case of suspected co-involvement of the trigeminal nerve in Korean literature. Therefore, in cases of RHS with severe rash over the face and neck, it is pertinent to give consideration to such multiple involvement in their early presentation. Facial nerve palsy and herpes related pain are the two worrisome complication, which could be alleviated by early treatment with neural blockade in addition to oral medication. Especially, nerve blocks are known to decrease the extent of nerve inflammation or damage, thereby facilitating recovery and probably preventing postherpetic neuralgia. We report two rare cases of Ramsay Hunt syndrome with trigeminal nerve involvement, where early implementation of blockade of somatic peripheral nerve branches, in addition to the conventional treatment, promoted early recovery.

Morphology and topography of the lingual nerve in Koreans

Two major salivary glands, submandibular duct, lingual nerve, and vessels are situated beneath the mouth floor. Among these, passing through the pterygomandibular space, lingual nerve is innervated to the lingual gingiva and the mucosa of mouth floor, and is responsible for the general sensation of the anterior two thirds of the tongue. So, the injury of the lingual nerve during an anesthesia or surgery in the retromolar area may cause complications such as a numbness, a loss of taste of the tongue and the other dysfunctions. Therefore, to find out the morphology and the course of lingual nerve and to clarify the topographical relationships of lingual nerve at the infratemporal fossa and paralingual space area, 32 Korean hemi-sectioned heads were dissected macroscopically and microscopically with a viewpoint of clinical aspect in this study. This study demonstrated various anatomical characteristics with relation to the course and topography of the lingual nerve in Koreans. And clinical significances based on the anatomical variations through the topography of the courses and communications between the mandibular nerve branches were described in details.

THE INDIRECT PATHWAY OF THE SOMATIC AFFERENT ELEMENTS FROM TRIGEMINAL NERVE TO NUCLEUS TRACTUS SOLITARII——A LIGHT AND ELECTRON MICROSCOPIC HRP TRANSGANGLIONIC AND RETROGRADE TRACING STUDY / 解剖学报

The indirect pathway of the somatic afferent elements from trigeminal nerve (TGN) to nucleus tractus solitarii (NTS) was studied with the light and electron microscopic HRP transganglionic and retrograde tracing. After HRP was injected into NTS at the level of obex, the retrogradely labeled cells were mainly found in the interstitial nucleus buried in the spinal tract of TGN along caudal subnucleus. The interstitial nucleus was also the terminating area of the primary afferent fibers of lingual and inferior orbital nerves. Under electron microscope, it was found that the primary afferent terminals of lingual and inferior orbital nerves formed synapses on the dendrites of neurons in the interstitial nucleus. Moreover, in cellular architecture, the interstitial nucleus and the superficial laminae of the caudal nucleus of TGN were similar and continuous with each other. Hence, the pathway from the TGN to NTS via the interstitial nucleus is consisted of two neurons and the sensations transmitted through this pathway may be considered to be somatic. It is presumed that this pathway composed of two neurons might modulate the visceral afferent function in NTS when certain points in the skin area innervated by TGN were acupunctured.