An anatomical study of additional radial wrist extensors including a unique extensor carpi radialis accessorius

Background: In this study, 82 forearms from 41 cadavers were dissected to establish the incidence of variant additional radial wrist extensors. Three variants have been described in the literature: extensor carpi radialis intermedius (ECRI), extensor carpi radialis accessorius (ECRA) and extensor carpi radialis tertius (ECRT). Materials and methods: Of the 41 cadavers studied, 5/41 (12%) had an additional radial wrist extensor. Of these 5 individuals, 2 had bilateral additional muscles and 3 were unilateral. Of the 82 forearms, 7/82 (9%) had additional radial wrist extensors. Results: We found 4 examples of ECRI and 3 examples of ECRA. We did not find any examples of ECRT. One specimen of ECRA had an atypical, previously undescribed, course. Conclusions: These accessory muscles are of clinical relevance, as they may be a contributing factor in tennis elbow and nerve entrapment, or cause diagnostic confusion, especially in ultrasound scans. However, they may also be used for tendon transfer. Of the 7 muscles found in the current study, 3 would have been suitable for such procedures.

Variations in carotid sinus anatomy and their relevance to carotid interventions.

BACKGROUND: The carotid sinus (CS) is a dilatation in the carotid bifurcation usually at the origin of proximal internal carotid artery (ICA). It contains baroreceptors which influence blood pressure. Variations in the location of the CS are of importance as atheromatous plaque commonly forms in this area and procedures such as carotid endarterectomy are performed to reduce the risk of stroke. Inadvertent stimulation of the CS baroreceptors during interventions can have profound effects on the patient's haemodynamic status both intra- and postoperatively, causing serious complications. The aim of this study is to determine the inter- and intra-individual variations in the location of the CS. MATERIALS AND METHODS: Eighty-two carotid arteries were dissected bilaterally from 41 cadavers. The locations of the CS were noted and divided into four potential sites. RESULTS: The commonest site is the origin of the ICA (74.3%), but the CS can also be found in the distal part of the common carotid artery (CCA) inferior to the bifurcation (17.1%); at the bifurcation involving the distal CCA and origins of both the external carotid artery (ECA) and ICA (7.32%); and at the origin of the ECA (1.22%). In individual cadavers, the CS was located at the origin of the ICA in 97.6% on at least one side. The sites of the CS were asymmetrical in 34.1%. CONCLUSIONS: Clinicians performing carotid interventions should be aware of these anatomical variations to avoid inadvertent stimulation of the CS which can cause profound bradycardia and hypotension

Study of anatomical variance of the zygomaticofacial foramen and determination of reliable reference points for surgery

Background: Dissection onto the facial aspect of the zygoma is necessary in several maxillofacial procedures. This carries inherent risk of damage to the vessels exiting the zygomaticofacial foramen (ZFF) on the facial aspect of the zygoma. Objectives: The aim was to compare ZFF anatomy between ethnic groups and sexes, and to determine reliable reference points for surgery. Methods: 858 zygomatic bones on dry adult skulls were used in the study. Skulls were selected from nine different geographic regions for a comparison between ethnic groups, and a comparison of anatomy between sexes was completed. Each zygoma was examined for the number of ZFF, after which a cross-line laser was used to create two consistent lines from which the ZFF was measured and mapped. Findings: There were significant differences in number and location of ZFF between ethnic groups, but not between sexes. Of all 858 sides, 1 ZFF was most commonly identified (49.8%). However, foramina number ranged from 0 to 4 per zygoma. Despite this variability over 80% of ZFF bilaterally were found within a 15 mm diameter circle centred at 5 mm anterior to the intersection of lines discussed above. Moreover, over 90% of ZFF fell beyond an arc of 5 mm from the orbital margin. Conclusion: We present a novel method of identifying a ‘ZFF zone’ within which the majority of foramina lie. This simple technique can be of use in directing osteotomy sites, local nerve blocks, and in preventing iatrogenic damage to the ZFF neurovascular bundle

Endoscopy International Open

Background and study aim Magnetic imaging technology is of proven benefit to trainees in colonoscopy, but few studies have examined its benefits in experienced hands. There is evidence that colonoscopy is more difficult in women. We set out to investigate (i) associations between the looping configurations in the proximal and distal colon and (ii) differences in the looping prevalence between the sexes. We have examined their significance in terms of segmental intubation times and position changes required for the completion of colonoscopy. Patients and methods We analyzed 103 consecutive synchronized luminal and magnetic image videos of diagnostic colonoscopies with normal anatomy undertaken by a single experienced operator. Results Deep transverse loops and sigmoid N-loops were more common in females. A deep transverse loop was more likely to be present if a sigmoid alpha-loop or N-loop had formed previously. Patients with sigmoid N-loops were turned more frequently from left lateral to supine before the sigmoid-descending junction was reached, but there was no statistical correlation between completion time and looping pattern. Conclusions This study has reexamined the prevalence of the common looping patterns encountered during colonoscopy and has identified differences between the sexes. This finding may offer an explanation as to why colonoscopy has been shown to be more difficult in females. Although a deep transverse loop following a resolved sigmoid alpha loop was the most commonly encountered pattern, no statistical correlation between completion time and looping pattern could be shown. It is the first study to examine segmental completion times using a magnetic imager in expert hands

Re: the role of radiology in anatomy teaching in UK medical schools: a national survey. A reply.

Sir – We thank Raja and colleagues1 for their interest in our article and share their enthusiasm for the integration of radiology in anatomy teaching. This is something that we feel passionate about. Two of our authors are full-time practicing consultant radiologists with additional roles as medical educators in anatomy teaching at the University of Cambridge medical school

'Can you be a doctor, even if you faint?' The tacit lessons of cadaveric dissection

Background: The undergraduate Medicine course at the University of Cambridge has included cadaveric dissection as part of its anatomy teaching for over three centuries. In recent years, medical schools in the UK and the US have debated whether cadaveric dissection is a useful and efficient way of teaching anatomy. Existing research on this subject has focused narrowly on the knowledge-acquisition for medical students afforded through dissection, and thus we have broadened the scope of such considerations to include the emotional responses of medical students to the dissection process. Subjects and methods: The basis for this paper is a phenomenological analysis of response data gathered from 56 first year medical students at the University of Cambridge through written questionnaires and discussion groups before and after their first experiences of cadaveric dissection. Results: Our research suggests that there are in fact many more lessons taught and acquired through studying in the dissection room: they are tacit, emotional, experiential and dispositional. Conclusions: When this wider picture of the value of dissection is considered, a much stronger case for the continued inclusion of cadaveric dissection in the medical curriculum can be made, as it is a valuable and unique educational experience

The REBOA window: a cadaveric study delineating the optimum site for austere cannulation of the femoral artery for resuscitative endovascular balloon occlusion of the aorta

Introduction: Haemorrhage is the major cause of early mortality following traumatic injury. Patients suffering from non-compressible torso haemorrhage are more likely to suffer early death. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) can be effective in initial resuscitation; however, establishing swift arterial access is challenging, particularly in a severe shock. This is made more difficult by anatomical variability of the femoral vessels. Methods: The femoral vessels were characterised in 81 cadaveric lower limbs, measuring specifically the distance from the inferior border of the inguinal ligament to the distal part of the origin of the profunda femoris artery (PFA), and from the distal part of the origin of the PFA to where the femoral vein lies posterior to and is completely overlapped by the femoral artery. Results: The femoral vein lay deep to the femoral artery at a mean distance of 105 mm from the inferior border of the inguinal ligament. The PFA arose from the femoral artery at a mean distance of 51.1 mm from the inguinal ligament. From the results, it is predicted that the PFA originates from the common femoral artery approximately 24 mm from the inguinal ligament, and the femoral vein is completely overlapped by the femoral artery by 67.7 mm distal from the inguinal ligament, in 95% of subjects. Conclusions: Based on the results, proposed is an ‘optimal access window’ of up to 24 mm inferior to the inguinal ligament for common femoral arterial catheterisation for pre-hospital REBOA, or more simply within one finger breadth

Sexual dimorphism and geographical variance: their impact on the reliability of the antilingula as a landmark in human mandibular surgery.

The intraoral vertical ramus osteotomy (IVRO) is an orthognathic procedure that is used to correct dentofacial abnormalities, and is performed by approaching the lateral aspect of the mandibular ramus. This approach, however, precludes visualisation of the inferior alveolar nerve (IAN) on the medial side, thereby placing it at risk of iatrogenic damage. The antilingula, a bony prominence on the lateral mandibular ramus, has been proposed as a landmark for prediction of the IAN's location during IVRO. The current study aimed to evaluate the variation in incidence and position of the antilingula, and therefore to determine its suitability as a surgical landmark during IVRO. The study included 480 dry hemimandibles from eight geographical populations from the Duckworth Collection in Cambridge. Skulls were sexed by visual analysis of dimorphic traits. Positional relations were determined through the digitisation of nine anatomical landmarks. The antilingula was identified in all specimens. No significant difference was identified in the positional relation between the antilingula and mandibular foramen between sexes, but multiple differences were identified in this relation between geographical populations. Our data showed that, irrespective of geographical variation, an osteotomy performed 8mm posterior to the antilingula would avoid the mandibular foramen in 98.8% of cases

An anatomical study of additional radial wrist extensors including a unique extensor carpi radialis accessorius.

BACKGROUND: In this study, 82 forearms from 41 cadavers were dissected to establish the incidence of variant additional radial wrist extensors. Three variants have been described in the literature: extensor carpi radialis intermedius (ECRI), extensor carpi radialis accessorius (ECRA) and extensor carpi radialis tertius (ECRT). MATERIALS AND METHODS: Of the 41 cadavers studied, 5/41 (12%) had an additional radial wrist extensor. Of these 5 individuals, 2 had bilateral additional muscles and 3 were unilateral. Of the 82 forearms, 7/82 (9%) had additional radial wrist extensors. RESULTS: We found 4 examples of ECRI and 3 examples of ECRA. We did not find any examples of ECRT. One specimen of ECRA had an atypical, previously undescribed, course. CONCLUSIONS: These accessory muscles are of clinical relevance, as they may be a contributing factor in tennis elbow and nerve entrapment, or cause diagnostic confusion, especially in ultrasound scans. However, they may also be used for tendon transfer. Of the 7 muscles found in the current study, 3 would have been suitable for such procedures

Neutralisation of SARS-CoV-2 by anatomical embalming solutions.

Teaching and learning anatomy by using human cadaveric specimens has been a foundation of medical and biomedical teaching for hundreds of years. Therefore, the majority of institutions that teach topographical anatomy rely on body donation programmes to provide specimens for both undergraduate and postgraduate teaching of gross anatomy. The COVID-19 pandemic has posed an unprecedented challenge to anatomy teaching because of the suspension of donor acceptance at most institutions. This was largely due to concerns about the potential transmissibility of the SARS-CoV-2 virus and the absence of data about the ability of embalming solutions to neutralise the virus. Twenty embalming solutions commonly used in institutions in the United Kingdom and Ireland were tested for their ability to neutralise SARS-CoV-2, using an established cytotoxicity assay. All embalming solutions tested neutralised SARS-CoV-2, with the majority of solutions being effective at high-working dilutions. These results suggest that successful embalming with the tested solutions can neutralise the SARS-CoV-2 virus, thereby facilitating the safe resumption of body donation programmes and cadaveric anatomy teaching