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Concept: Dissection

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OBJECTIVE: To present a group of anatomical findings that may have clinical significance. DESIGN: This study is an anatomical case report of combined lumbo-pelvic peripheral nerve and muscular variants. Setting: University anatomy laboratory. Participants: One cadaveric specimen. METHODS: During routine cadaveric dissection for a graduate teaching program, unilateral femoral and bilateral sciatic nerve variants were observed in relation to the iliacus and piriformis muscle, respectively. Further dissection of both the femoral nerve and accessory slip of iliacus muscle was performed to fully expose their anatomy. RESULTS: Piercing of the femoral nerve by an accessory iliacus muscle combined with wide variations in sciatic nerve and piriformis muscle presentations may have clinical significance. CONCLUSIONS: Combined femoral and sciatic nerve variants should be considered when treatment for a lumbar disc herniation is refractory to care despite positive orthopedic testing.

Concepts: Spinal disc herniation, Biology, Muscle, Sciatic nerve, Sciatica, Lumbar plexus, Dissection, Piriformis muscle

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BACKGROUND: Transnasal cannulation of the natural ostium in patients with an intact uncinate process is complicated by the lack of direct visualizationof the ostium. Accuracy of transnasal dilation of the maxillary ostium was evaluated for a malleable-tipped balloon device that was bent to specific angles for avoiding the fontanelle during cannulation.METHODS: Transnasal cannulation and dilation of 42 cadaver maxillary sinus ostia was attempted by 6 surgeons including 3 with very limited clinicalexperience using the study device. All physicians received procedure training including the technique to shape the balloon device into the recommended 135 degree maxillary configuration. Tissue dissection was prohibited. Canine fossa trephination and transantral endoscopy were used to evaluate cannulation and dilation outcomes. Physician operators were blinded to transantral images and results were documented by two observers.RESULTS: Appropriate transnasal cannulation and dilation of natural maxillary sinus ostia occurred in 92.9% (39/42) of attempts. Two failures emanated from procedural deviations. In one deviation, the bend angle was changed to 90 degrees and the device tip did not cannulate the ostium. In the second, the device was passed through a preexisting hole in the uncinate and cannulated the natural ostium. A third failure occurred when the device was passed through the fontanelle creating a false lumen.CONCLUSION: Using recommended procedural techniques and a malleable-tipped balloon device, newly trained and experienced physicians alike can perform uncinate-preserving transnasal cannulation and dilation of the maxillary ostium with a high rate of success.

Concepts: Sinusitis, Physician, Failure, Angle, Maxillary sinus, Cadaver, Dissection, Uncinate process of ethmoid bone

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Our objective was to investigate the pathway of the lingual nerve and find out whether it can be identified using ultrasonography (US) intraorally. It is a dominant sensory nerve that branches from the posterior division of the mandibular aspect of the trigeminal nerve, and is one of the two most injured nerves during oral surgery. Its anatomy in the region of the third molar has been associated with lingual nerves of variable morphology. If surgeons can identify its precise location using US, morbidity should decrease. We searched published anatomical and specialty texts, journals, and websites for reference to its site and US. Cadavers (28 nerves) were dissected to analyse its orientation at the superior lingual alveolar crest (or lingual shelf). Volunteers (140 nerves) had US scans to identify the nerve intraorally. Our search of published books and journals found that descriptions of the nerve along the superior lingual alveolar crest were inadequate. We found no US studies of the nerve in humans. Dissections showed that the nerve was above (n=6, 21%) and below (n=22, 79%) the crest of the lingual plate. US scans showed 140 lingual nerves intraorally in 70 volunteers. The nerve lay either above or below the superior lingual alveolar crest, which led us to develop a high/low classification system. US can identify the lingual nerve and help to classify it preoperatively to avoid injury. Our results suggest that clinical anatomy of the lingual nerve includes the superior lingual alveolar crest at the third and second molars because of its surgical importance. US scans can successfully identify the nerve intraorally preoperatively.

Concepts: Neuroanatomy, Cranial nerves, Anatomy, Mandibular nerve, Tongue, Trigeminal nerve, Dissection, Lingual nerve

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: The sural nerve is commonly used as donor for nerve grafting. Contrary to its constant retromalleolar position, formation and course of the proximal sural nerve show great variability. The coexistence of different and deceptive terminologies contributes to the complexity, and reviewing the international literature is confusing. Because detailed anatomical knowledge is essential for efficient and safe sural nerve harvesting, this study aims to bring clarity.

Concepts: Anatomy, Review, Human anatomy, Dissection, Sural nerve

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PURPOSE: The posterior forearm is an excellent donor site for the vascular pedicled cutaneous flaps; yet, there is surprisingly little detailed anatomical information based on clinical decision making. This study was undertaken to evaluate the anatomical basis of the dorsal forearm perforator flaps and to provide anatomical landmarks to facilitate flap elevation. METHODS: Thirty cadavers were available to perform this anatomical study after arterial injection. Twenty fresh cadavers were injected with a modified lead oxide-gelatin mixture, selected for 3-dimensional reconstruction using special software (MIMICS) and the arterial territory measured with Scion Image. Other ten were injected with red latex preparation, and perforators were identified through dissection. RESULTS: (1) The average number of posterior interosseous artery cutaneous perforators in the dorsal forearm was 5 ± 2, the average diameter was (0.5 ± 0.1) mm, and the pedicle length was (2.5 ± 0.2) cm. The average cutaneous vascular territory was (22 ± 15) cm(2). Cutaneous perforators could be found along the line extending from the lateral epicondyle to the radial border of the head of ulna. (2) Dorsal branch of anterior interosseous artery supplied blood to distal third of dorsal forearm; its average diameter was 0.8 mm. CONCLUSION: The free transplantation of the posterior interosseous perforator artery flaps or rotary flap pedicled by dorsal branch of anterior interosseous artery for defect reconstruction is feasible.

Concepts: Blood, Forearm, Pronator quadratus, Arteries of the upper limb, Dissection, Common interosseous artery, Anterior interosseous artery, Posterior interosseous artery

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In laparoscopic colorectal resection, the medial-to-lateral approach has been largely adopted. This approach can be initiated by the division of either the inferior mesenteric artery (IMA) or the inferior mesenteric vein (IMV). This cadaveric study aimed to establish the feasibility of IMV dissection as the initial landmark of medial-to-lateral left colonic mobilization for evaluating the size of the peritoneal window between the IMV at the lower part of the pancreas and the origin of the IMA (IMA-IMV distance) and the point of origin of the IMA compared to the lower edge of the third part of the duodenum (IMA-D3 distance). These distances were recorded on 30 fresh cadavers. The IMA-D3 distance was 0.4 ± 2.2 cm (mean ± SD). The IMA originated from the aorta at the level of or below the D3 in 21 cases (70%). The IMA-IMV distance was 5.5 ± 1.8 cm and was greater or equal to 5 cm (large window) in 21 cases (70%). IMA-IMV distance was correlated with IMA-D3 showing that a large window was inversely correlated with a low IMA origin (P < 0.001). IMA-D3 distance was not correlated with weight, height and sex. IMA-IMV distance was largerin male (6.7 ± 0.9 vs. 4.9 ± 1.8, P = 0.001) and correlated with weight, (r = 0.60, 95%CI = 0.03-0.10, P < 0.001) and height (r = 0.54, 95%CI = 0.05-0.21, P = 0.002). IMV can be used as the initial landmark for laparoscopic medial-to-lateral dissection in two-thirds of cases. A too-small window can require first IMA division. The choice between the two different medial-to-lateral approaches could be made by evaluating the anatomical relationship between IMA, IMV, and D3. Clin. Anat., 2013. © 2013 Wiley Periodicals, Inc.

Concepts: Digestive system, Colon, Abdominal aorta, Peritoneum, Dissection, Inferior mesenteric artery, Inferior mesenteric vein, Left colic artery

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Low back pain is very common, but the pathophysiology is poorly understood. We present a new hypothesis regarding the pathophysiology of common low back pain supported by our flexible endoscopic observations of the epidural cavity (epiduroscopy), anatomic dissection of embalmed and fresh cadavers, and careful review of preexisting information available on the anatomy of the epidural space and neuroforamen. A new approach to the treatment of common low back pain based on the hypothesis was developed and is presented in the case reports of five patients. Treatment focuses on a perichondrium derivative; the peridural membrane, which creates a suprapedicular compartment in the neuroforamen where we hypothesize inflammatory material accumulates. This produces common low back pain by causing inflammation and sensitization of the peridural membrane and periosteum that forms the boundaries of this compartment. Percutaneous Ablation and Curettage and Inferior Foraminotomy (PACIF(sm) ) aims to destroy the peridural membrane, denervate sensitive structures, and remove inflammatory tissues from the suprapedicular canal. The proposed mechanism of action and safety of PACIF(sm) is discussed in the context of epidural and neuroforaminal anatomy. As shown by the five case reports, PACIF(sm) appears to be highly effective and safe, warranting further evaluation.

Concepts: Scientific method, Low back pain, Back pain, Observation, Epidural, Dissection, Epidural space

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The literature contains confusing and opposing views about the naming, prevalence, anatomic structure, and clinical significance of the arcade of Struthers. The conflicting rates of arcade (between 0% and 100%) prevalence found in the literature may be due to the varying definition of the arcade among the authors, as well as the dissection method.The present study aims to examine the structure to determine whether or not the arcade of Struthers exists through an anatomic dissection study of a fresh human cadaver and seeks to compare its findings with those in the literature. Twenty arms from fresh frozen cadavers were dissected. An arcade of Struthers was not found in any specimen. Study concluded that its existence is unproven, and the arcade of Struthers does not exist.

Concepts: Biology, Ontology, Anatomy, Existence, Reality, Cadaver, Dissection, Plato

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The objective of this study is to assess surgical parameters correlating with voice quality after total laryngectomy (TL) by relating voice and speech outcomes of TL speakers to surgical details. Seventy-six tracheoesophageal patients' voice recordings of running speech and sustained vowel were assessed in terms of voice characteristics. Measurements were related to data retrieved from surgical reports and patient records. In standard TL (sTL), harmonics-to-noise ratio was more favorable after primary TL + postoperative RT than after salvage TL. Pause/breathing time increased when RT preceded TL, after extensive base of tongue resection, and after neck dissections. Fundamental frequency (f0) measures were better after neurectomy. Females showed higher minimum f0 and higher second formants. While voice quality differed widely after sTL, gastric pull-ups and non-circumferential pharyngeal reconstructions using (myo-)cutaneous flaps scored worst in voice and speech measures and the two tubed free flaps best. Formant/resonance measures in/a/indicated differences in pharyngeal lumen properties and cranio-caudal place of the neoglottic bar between pharyngeal reconstructions, and indicate that narrower pharynges and/or more superiorly located neoglottic bars bring with them favorable voice quality. Ranges in functional outcome after TL in the present data, and the effects of treatment and surgical variables such as radiotherapy, neurectomy, neck dissection, and differences between partial or circumferential reconstructions on different aspects of voice and speech underline the importance of these variables for voice quality. Using running speech, next to sustained/a/, renders more reliable results. More balanced data, and better detail in surgical reporting will improve our knowledge on voice quality after TL.

Concepts: Assessment, Acoustics, Human voice, Singing, Outcome, Vowel, Surgical oncology, Dissection

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The specialty of laparoscopy has evolved with the advent of new technologies over the last few years. Energy-based devices and Ultrasonic dissectors are used with a lot of factors in play-including ergonomics and economics during surgery. Here an attempt is based to review the surgical efficacy and safety of these dissectors with importance to plume production and lateral thermal damage. The factors contributing to adversities to the dissectors are also to be noted. The strategy adopted was aimed at finding relevant studies from PubMed from 1995 to 2014. The basic principle of plume production and thermal damage are studied in this review. Factors contributing to the same that can lead to adversities during laparoscopic surgeries are identified. Summarizing key points that increase lateral thermal damage and plume production amongst different ultrasonic shears and suggesting a technique to identify the right balance between the existing dissectors was possible. The RF Device and USS are both useful and widely used and are more safer than monopolar devices. RF Device is considerably slower than USS, as it cannot achieve coagulation and cutting at the same time. Although USS definitely improvises dissection and has less thermal injury than RF Device, the clinical implications in balancing dissection efficacy with hemostasis need to be investigated further. The ideal haemostatic energy-based shear device would be one with excellent hemostatic results and visual acuity while allowing none or minimal thermal energy escape at the point of application. In our current setting, a combined use of both RF and USS device usage as applied in the particular situations has potential.

Concepts: Surgery, Hemostasis, Al-Andalus, Laparoscopic surgery, Laparoscopy, Scalpel, Antihemorrhagic, Dissection