Anatomic mapping of the collateral branches of the external carotid artery with regard to daily clinical practice.

BACKGROUND: To identify the anatomical variations of the main branches of the external carotid artery (lingual, facial, occipital, ascending pharyngeal and sternocleidomastoid), giving information about the calibers and origins with the aim of creating a new classification useful in clinical practice. MATERIAL AND METHODS: 193 human embalmed body-donors were dissected. The data collected were analyzed using the Chi² test. The results of previous studies were reviewed. RESULTS: The majority of the anterior arterial branches (superior thyroid, facial and lingual artery) were observed with an independent origin, respectively, classified as pattern I (80.83%, 156/193). In 17.62% (34/193) a linguofacial trunk, pattern II, has been observed, only in 1,04% (2/193) a thyrolingual trunk, pattern III, has been found and in one case (1/193, 0.52%) one thyrolinguofacial trunk, pattern IV, was found. Depending on the posterior branches (occipital and ascending pharyngeal), four different types could be determined: type a, the posterior arteries originated independently, type b, the posterior arteries originated in a common trunk, type c, the ascending pharyngeal artery was absent, type d, the occipital artery was absent. CONCLUSION: Anatomical variations in these arteries are relevant in daily clinical practice due to growing applications, e.g., in Interventional Radiology techniques. Knowledge of these anatomical references could help clinicians in the interpretation of the carotid system.

Cadaveric surgery: a novel approach to teaching clinical anatomy.

INTRODUCTION: Anatomy is an essential basic science for safe and effective medical practice. In 2006 the UK Anatomy Act was changed to allow the use of surgical procedures on cadavers. This has unlocked opportunities for new methods of teaching clinically relevant anatomy. This study explores how surgical procedures may provide a purposeful and memorable way for undergraduates to learn anatomy, compared with conventional teaching methods. METHODS: Under supervision, a group of third-year medical students prepared for and then performed a shoulder hemi-arthroplasty after identifying key anatomical structures and surgical objectives. The procedure was performed in a simulated theatre environment. A focus group was used to collect qualitative data based on the learning experience. RESULTS: The surgical approach and implant insertion were successfully completed, and the educational objectives of identifying and learning surrounding structures were met. The focus group found that the exercise presented a relaxed introduction to surgery, enabled learning by association, and provided a learning experience that was both purposeful and complete. DISCUSSION: The preparation and completion of the procedure enabled the students to focus on the anatomy of the shoulder, by identifying and forming associations with surrounding structures. Uniquely, the surgical nature of this project also allowed undergraduate students to practice key surgical skills and principles. CONCLUSION: The authors believe that learning anatomy via a surgical approach provides a relevant, in-depth, purposeful and enjoyable learning experience. This technique also provided a valuable insight into surgery.

Anatomical variations of the superior thyroid and superior laryngeal arteries.

BACKGROUND: There are known to be variations in the origins of the superior thyroid artery (STA), an important surgical landmark, and 1 of its branches, the superior laryngeal artery (SLA). METHODS: Three hundred thirty human embalmed heminecks were dissected. The results of previous studies were reviewed, and a meta-analysis is presented. RESULTS: Four different origins for the STA were found. The most frequent was type I, from the carotid bifurcation (49%). Four different origins were also found for the SLA being the most frequent the type I in which the artery arose from STA (78%). The mean external diameters of STA and SLA were 0.26 and 0.20 cm, respectively, with no statistically significant differences by side or sex. CONCLUSION: Variations in the origin of STA and SLA from the carotid arterial tree and the similarity of their diameters mean that there is a significant possibility of their misidentified during surgery.

Anatomic study of blood supply of the dorsum of the foot and ankle.

PURPOSE: This project was to study the different patterns of the anterior tibal and dorsalis pedis arteries in relation to the blood supply of the dorsum of the foot and ankle. METHODS: A reliable sample of 150 human embalmed cadavers was dissected. RESULTS: Four different patterns were identified. The dorsalis pedis artery was most frequently (287 cases, 95.7%) found to be the continuation of the anterior tibial artery distal to the ankle, and lay between the tendon of extensor hallucis and the first tendon of extensor digitorum longus. The other 13 cases (4.3%) showed 3 variant patterns of the anterior tibial-dorsalis pedis vascular axis: the anterior tibial artery took a more lateral course, passing in front of the lateral malleolus (6 cases, 2%); the perforating branch of the peroneal artery assumed the expected course of the dorsalis pedis artery (4 cases, 1.3%); the anterior tibal artery gave a lateral branch that replaced the perforating branch of the peroneal artery to supply the lateral aspect of the ankle (3 cases, 1%). CONCLUSION: Arterial variations of the anterior tibial-dorsalis pedis axis occurred in almost 5% of cases. CLINICAL RELEVANCE: An awareness of the existence of such variations is helpful during a preoperative assessment and could prevent injury during surgery.

The anatomy of sartorius muscle and its implications for sarcoma radiotherapy.

PURPOSE: Controversy exists as to whether sartorius muscle is completely invested in fascia. If it is, then direct tumour involvement from soft tissue sarcoma of the anterior thigh would be unlikely and would justify omitting sartorius from the radiotherapy volume. SUBJECTS AND METHODS: Eight thighs in six cadavers were examined in the dissecting room. Using a previous case, conformal radiotherapy plans were prepared to treat the anterior compartment of the thigh including and excluding sartorius. The corridor of unirradiated normal tissue was outlined separately. RESULTS: In all cases, sartorius was enclosed within a fascial sheath of its own. In four of the six cadavers, there was clear evidence of a fascial envelope surrounding sartorius, fused to the fascia lata and medial intermuscular septum. In two, sartorius was fully ensheathed in the upper half of the thigh; in the lower half the intermuscular septum became thin, and blended with the tendinous aponeurosis on the surface of vastus medialis in an example case. By excluding sartorius, the volume of the anterior compartment was reduced by 8%, but the volume of the unirradiated normal tissue corridor increased by 134%. With sartorius included, the unirradiated corridor became very small inferiorly, only 6% of the circumference of the whole leg, compared to 27% with sartorius excluded. DISCUSSION: The anatomy suggests that sartorius could be safely omitted from the clinical target volume of anterior compartment soft tissue sarcomas. This substantially increases the size of the unirradiated normal tissue corridor, expressed as a volume and a circumference, which could give a clinical advantage by reducing normal tissue complications.

Extensor digitorum brevis manus: anatomical, radiological and clinical relevance. A review.

The extensor digitorum brevis manus (EDBM) is a supernumerary muscle in the dorsum of the hand frequently misdiagnosed as a dorsal wrist ganglion, exostosis, tendon sheath cyst or synovitis. Its presence in a living subject, confirmed by magnetic resonance imaging (MRI), is presented together with a review of the hitherto reported cases and the results of an anatomical study on 128 adult human cadavers (59 males and 69 females). The EDBM was found in three (2.3%) of the 128 cadavers. It occurred in two (3.4%) of the 59 male cadavers (one bilateral and one unilateral on the right side) and in one (1.5%) of the 69 female cadavers (unilateral on the left side). Consequently, the EDBM was found in four (1.6%) of the 256 upper limbs. It originated from the dorsal wrist capsule within the compartment deep to the extensor retinaculum for the extensor digitorum and inserted into the extensor hood of the index finger in one case and into that of the middle finger in three cases. In both hands of the living subject, the origin was similar but the insertion was into the index and middle fingers. In all cases, it was innervated by the posterior interosseous nerve and its blood supply was provided by the posterior interosseous artery.