Ultrasound identification of hand and wrist anatomical structures by hand surgeons new to ultrasonographic techniques.

PURPOSE: Ultrasound is becoming an essential tool for hand surgeons, but most of them are trained on the job, without any diploma or dedicated training. The aim of this study was to assess the ability of hand surgeons new to ultrasound to identify hand and wrist anatomical structures. METHODS: A monocentric study was conducted from January 2022 to April 2022. Ten residents and five attending hand surgeons, ultrasound novices, were involved in this study. The participants underwent two tests, wherein they were required to identify 17 anatomical structures using ultrasound, on the same subject. The second test was similar and carried out 2 to 6 weeks later by all participants. The number of structures successfully identified and if it was the case, the detection time per structure, were recorded. The correlations between participants age, years of surgical experience, surgical background (orthopedic or plastic) and the ability to perform immediately during the first test or to progress between the two tests were also assessed. RESULTS: The average number of structures identified during the first test (T1) was 14.1+/-2.1 (82.9%), versus 16.2+/-0.8 (95.3%) structures during the second test (T2) (p = 0.001). The mean detection time per structure was 53.4 +/- 18.9 s during T1 versus 27.7 +/- 7.2 s during T2 (p < 0.0001). A moderate negative correlation between the progression in the number of anatomical structures identified between the two tests and the years of surgical experience (ρ=-0.56; p = 0.029) was found. The other parameters were neither correlated with the ability to perform at the first test nor with the progression between the two tests. CONCLUSION: Hand surgeons new to ultrasound are most of the time able to identify hand and wrist anatomical structures. Comparison of their first and second tests showed significant potential for improvement in anatomical structure identification and detection time of those, especially in surgeons with limited surgical experience.

The potential role of ChatGPT and artificial intelligence in anatomy education: a conversation with ChatGPT.

PURPOSE: A recent study published in the JMIR Med Educ Journal explored the potential impact of the Generative Pre-Train (ChatGPT), a generative language model, on medical education, research, and practice. In the present study, an interview with ChatGPT was conducted to determine its capabilities and potential for use in anatomy education (AE) and anatomy research (AR). METHODS: The study involved 18 questions asked of ChatGPT after obtaining an online subscription to the 4th edition. The questions were randomly selected and evaluated based on accuracy, relevance, and comprehensiveness. RESULTS: The ChatGPT provided accurate and well-structured anatomical descriptions, including clinical relevance and relationships between structures. The chatbot also offered concise summaries of chapters and helpful advice on anatomical terminology, even with complex terms. However, when it came to anatomical variants and their clinical significance, the chatbot's replies were inadequate unless variants were systematically classified into types. ChatGPT-4 generated multiple-choice quizzes and matching questions of varying difficulty levels, as well as summaries of articles when presented with text. However, the chatbot recognized its limitations in terms of accuracy, as did the authors of the current study. CONCLUSION: ChatGPT-4 can be a valuable interactive educational tool for students in the field of anatomy, encouraging engagement and further questions. However, it cannot replace the critical role of educators and should be used as a complementary tool. Future research should establish guidelines for ChatGPT's optimal use and application in medical education.

Cutaneous vascularization of the proximal two-thirds of the dorsal aspect of the hand: descriptive anatomical study of a perforating arterial arch.

PURPOSE: Several reports have suggested that transverse arches between the radial and ulnar sides of dorsal hand skin supply the proximal part of the skin. The main objective of the study was to provide an anatomical and radiological description of a superficial vascular arch in the proximal third of the metacarpals of the long fingers. METHODS: We dissected 11 hands after injection with a mixture of lead and resin. A CT scan was performed before dissection. All vessels supplying the skin were individualized on the back of the hand and measured. RESULTS: A superficial perforating dorsal arch of the hand was present in all cases in this study. It was supplied by a dorsal radial perforating artery arising from the radial artery and by a dorsal ulnar perforating artery arising from the dorsal carpal arch. The distal recurrences of the intermetacarpal spaces communicated with this arch. This arch was the only source of vascularization of thess proximal third of the third space and presented a dominant ulnar side in the majority of cases. It presented numerous anatomical variations. The source vessels had mean diameters of 0.5 mm. There was an excellent radiological-anatomical correlation on CT scan. CONCLUSION: Given the constancy of this arch in the study, perforating flaps not yet described could be considered, having as pivot points the ulnar or radial origin of this arch.

Advantages of ultrasound identification of the distal insertion of the calcaneofibular ligament during ligament reconstructions.

INTRODUCTION: In lateral ankle instability, anatomical ligament reconstructions are generally performed using arthroscopy. The ligament graft is passed through the talar, fibular and calcaneal tunnels, reconstructing the anterior talofibular and calcaneofibular (CFL) bundles. However, the calcaneal insertion of the CFL needs to be performed in an extra-articular fashion, and cannot be carried out under arthroscopy, thus requiring specific anatomical landmarks. For obtaining these landmarks, methods based on radiography or surface anatomy have already been described but can only offer an approximate identification of the actual CFL anatomical insertion point. In contrast, an ultrasound technique allows direct visualization of the insertion point and of the sural nerve that may be injured during surgery. Our study aimed to assess the reliability and accuracy of ultrasound visualization when performing calcaneal insertion of the CFL with specific monitoring of the sural nerve. MATERIALS AND METHODS: Our anatomical study was carried out on 15 ankles available from a body donation program. Ultrasound identification of the sural nerve was obtained first with injection of dye. A needle was positioned at the level of the calcaneal insertion of the CFL. After dissection, in all the ankles, the dye was in contact with the sural nerve and the needle was located in the calcaneal insertion area of the CFL. The mean distance between the sural nerve and the needle was 4.8 mm (range 3-7 mm). DISCUSSION AND CONCLUSION: A pre- or intra-operative ultrasound technique is a simple and reliable means for obtaining anatomical landmarks when drilling the calcaneal tunnel for ligament reconstruction of the lateral plane of the ankle. This tunnel should preferably be drilled obliquely from the heel towards the subtalar joint (1 h-3 h direction on an ultrasound cross section), which preserves a maximum distance from the sural nerve for safety purposes, while allowing an accurate anatomical positioning of the osseous tunnel.

Bulky supernumerary bone of the falx cerebri: case report and literature review.

We present a rare case of ossification of the falx cerebri in a 25-year-old man, discovered incidentally on a craniofacial computed tomodensitometry (CT) scanner. This ossification presented a true cortico-medullary differentiation and pushed aside the right frontal lobe. There was no associated clinical manifestation.

The distal dorsal intermetacarpal ligament: characterization of an overlooked structure-an anatomical study of 25 hands.

PURPOSE: Exhaustive literature is available on the metacarpophalangeal joints of the long fingers, but the dorsal ligamentous structure overlaying the interosseous muscles and joining the metacarpal heads of the long fingers remains to be fully characterized. Previously, our surgical hand team observed a non-classically reported structure connecting the metacarpal heads of the long fingers, in the dorsal part of the intermetacarpal spaces. Therefore, the aim of this anatomical study was to characterize this ligamentous structure in terms of size, insertions, and anatomical position. METHODS: Twenty-five hands were dissected for a total of 75 long finger intermetacarpal spaces. A ligamentous structure was exposed after cellular tissue excision and dorsal superficial fascia opening. The length and thickness were measured and anatomical position and insertions were studied. Histological analysis was performed on five specimens and ultrasound analysis in one healthy subject. RESULTS: All 25 dissections revealed a dorsal ligamentous structure, hereafter named distal dorsal intermetacarpal ligament, which was inserted in the lateral tubercle of each adjacent long finger metacarpal head. This distal dorsal intermetacarpal ligament surrounded interosseous tendons. It was more proximal compared to oblique and transversal interosseous muscle fibers. Histological analysis confirmed the ligamentous nature of the structure. Ultrasound analysis showed that this structure was well identified under the dorsal aspect of the hand. CONCLUSION: All dissections revealed a tense ligamentous structure between each metacarpal head of the long fingers. This was a constant structure meeting the definition of a ligament. The distal dorsal intermetacarpal ligament seems to stabilize the metacarpal heads at the second and fourth spaces by limiting hyperabduction.

The sphenoidal emissary foramina prevalence: a meta-analysis of 6,369 subjects.

PURPOSE: To estimate the prevalence of the sphenoidal emissary foramina (SEF), and the effect of possible moderators on it. METHODS: A systematic online literature search was conducted. The pooled prevalence with 95% confidence intervals was estimated. Outlier and influential analyses were performed. The presence of small-study effect and publication bias were evaluated. Moderator analyses were executed to investigate the effect of the specimens' continent of origin, type of study (dried skull or imaging), probing for the evaluation of SEF patency (conduction and instruments used), side dominance (bilateral or unilateral), morphometric data [SEF diameter, distances SEF-Foramen ovale (FO) and SEF-Foramen spinosum (FS)], and the methodology used for the morphometric measurements (caliper, DICOM Viewer, and image analysis software) on the estimated prevalence. RESULTS: In total, 6,460 subjects from 26 studies were included in the meta-analysis. The overall SEF prevalence was estimated as 38.1%. The heterogeneity was high and statistically significant. No indications of publication bias and small-study effect were identified. The conducted subgroup analyses did not yield statistically significant differences in the SEF prevalence between groups, except of the type of side dominance. Both results of the univariable and multivariable regression analyses showed the association of the unilateral dominance with a decrease in the reported SEF prevalence. CONCLUSION: The identification of more unilateral than bilateral foramina in a given cohort is associated with a decrease in the reported crude SEF prevalence. Laterality-specific estimates should be established for a precisive estimation of the emissary foramina prevalence.

Common carotid artery medialization and fracture dislocation of the cervical spine.

PURPOSE: To describe the management of the discovery of a retropharyngeal carotid artery in the context of a cervical dislocation. DESCRIPTION OF THE CASE: A 68-year-old female presented acute neck pain and incomplete tetraplegia following a fall on the stairs. Radiographs, contrast-enhanced computed tomography scan and magnetic resonance of the cervical spine revealed a C5-C6 bi-articular dislocation. A detailed preoperative assessment of the images discovered a medialization of the left common carotid artery. An external reduction and a left anterior cervical approach allowed a careful management of the vascular variation and an anterior C5-C6 arthrodesis. At six months, a full neurological recovery was assessed and radiographs demonstrated successful fusion of the cervical arthrodesis. DISCUSSION/CONCLUSION: Anatomical features such as medialization of the common carotid artery may affect patients with traumatic cervical spine injuries. The severity of the traumatic bone lesions should not overshadow the preoperative analysis of the adjacent anatomical structures encountered during the surgical approach, even in an emergency situation.

Preauricular anteroparotid transmasseteric approach of the mandibular condyle: The natural evolution after cervical dissections? An anatomical feasibility study.

The purpose of this study was to evaluate the reliability and reproducibility of a novel approach for base and neck fractures of the mandible. An anatomical study was conducted on 22 given to Science subjects. A rhytidectomy-like approach was performed, followed by a transmasseteric anteroparotid dissection. Measures were taken of the incision length and bone exposure at every step. The identification of a ramus of the facial nerve during dissection was noted. The subjects were classified according to their facial adiposity. A correlation coefficient was measured between incision length and bone exposure as well as morphotype and bone exposure. Statistical analysis was carried out using the Pearson method for linear correlation, and Chi2 test for further analysis. Adequate condylar exposure was always achieved in the area of interest (i.e. in the main localization of base and neck fractures). There was no correlation between the length of the cranial cutaneous backcut and the bone exposure horizontally (p = 0.3296) or vertically (p = 0.8382). There was no correlation between the total length of the incision and the bone exposure horizontally (p = 0.5171) or vertically (p = 0.8404). There was a significant correlation between the subjects' facial adiposity and the bone exposure horizontally and vertically (p<0.005). This approach allowed adequate bone exposure to the mandible base and neck, with a possible 90° angulation of instruments for optimal bone fixation. The incidence of facial nerve rami identification during dissection was similar to other approaches. The scarring was hidden. These results allowed us to propose this approach in a clinical study.

The left-sided aortic arch variants: prevalence meta-analysis of imaging studies.

PURPOSE: To estimate the prevalence of the left-sided aortic arch (LSAA) variants, and the effect of possible moderators on variants' detection. METHODS: A systematic online literature search was conducted. The pooled prevalence with 95% confidence intervals was estimated for the typical and atypical branching patterns to compare the overall proportions of different variants. Meta-regression analyses were performed to investigate the effect of the subjects' gender and geographical region, and the multidetector computed tomography (MDCT) scanner's technology on the estimated prevalence. RESULTS: In total, 18,075 cases from 23 imaging studies were included and 33 different LSAA variants were detected. The estimated heterogeneity was statistically significant. Based on the estimated prevalence, approximately 77% of the population is expected to have the typical branching anatomy with sequence brachiocephalic trunk-left common carotid artery-left subclavian artery, and 23% variant branching patterns. Approximately 71%, 23%, 2%, and 0.1% of the atypical populations are expected to have two, four, three, and five emerging branches, respectively. The meta-regression analyses showed that the number of detector rows of the MDCT scanner, and the subjects' geographical region are statistically significant moderators of the estimated prevalence. CONCLUSION: The current findings indicate that the prevalence of the LSAA variant branching anatomy is significantly affected by the subjects' geographical region and the MDCT scanner's technological improvement, with the advanced scanners to facilitate the detection of the aortic arch variants. However, due to the heterogeneity among studies, further research is required.

Percutaneous Ultrasound-Guided Release of the Lacertus Fibrosus for Median Nerve Entrapment at the Elbow.

PURPOSE: The aim of this technical note is to present a microinvasive percutaneous ultrasound-guided release of the lacertus fibrosus of the biceps brachii for pronator syndrome, i.e., entrapment of the median nerve at the elbow. METHODS: Fifteen consecutive patients were included. Patients showed isolated pronator syndrome including pain plus reduced strength of specific median nerve innervated muscles. The release was performed in a non-operating interventional room under wide-awake local anesthesia no tourniquet (WALANT). It was conducted superficial to the pronator teres with in-plane ultrasound guidance. The recovery of strength was first assessed peroperatively, and then systematic visits at postoperative weeks 1 and 4 included assessments of both strength and pain. RESULTS: Procedures were comfortably completed with no immediate surgical or anesthetic complication. Muscle strength returned immediately and persisted at postoperative visits. Visual analog scores for pain reduced from 6.2 to 2.5 and 0.6 at weeks 1 and 4, respectively. All working patients were able to perform in their professional activities at week 1. The millimetric skin incision healed with no hypertrophic scar tissue. A small hematoma occurred at week 1 and resorbed spontaneously. No other delayed complication was observed. The procedure appeared effective with improved invasiveness compared to existing techniques. Real-time monitoring with ultrasound may improve the safety. The technique could be regarded as a new ultrasound-guided alternative to surgery. CONCLUSION: Performed superficial to the pronator teres muscle under WALANT anesthesia, the microinvasive percutaneous ultrasound-guided release of the lacertus fibrosus may be an effective treatment of pronator syndrome.

Standardized statement for the ethical use of human cadaveric tissues in anatomy research papers: Recommendations from Anatomical Journal Editors-in-Chief.

Human cadaveric donors are essential for research in the anatomical sciences. However, many research papers in the anatomical sciences often omit a statement regarding the ethical use of the donor cadavers or, as no current standardized versions exist, use language that is extremely varied. To rectify this issue, 22 editors-in-chief of anatomical journals, representing 17 different countries, developed standardized and simplified language that can be used by authors of studies that use human cadaveric tissues. The goal of these editor recommendations is to standardize the writing approach by which the ethical use of cadaveric donors is acknowledged in anatomical studies that use donor human cadavers. Such sections in anatomical papers will help elevate our discipline and promote standardized language use in others non anatomy journals and also other media outlets that use cadaveric tissues.

A proposal for a new classification of the Coracobrachialis longus: A rare case or a new, distinct muscle?

BACKGROUND: The coracobrachialis muscle, along with the brachialis and biceps brachii muscles, belong to the anterior group of the brachial region. It is characterized by high level of morphological variabilities, with a common variation being the coracobrachialis longus (CBL) muscle. The CBL may be recognized as a distal part of the coracobrachialis muscle, originating from the anteromedial surface of the humerus, however, the two muscles are distinct from each other, and the distal attachment of the CBL is longer and located closer to the elbow joint. The CBL muscle may also be inserted on to various structures. The aim of the present study was to determine the frequency of the CBL muscle among a studied population, and to prepare a classification based on its morphological features. MATERIAL AND METHODS: Classical anatomical dissection was performed on 100 upper limbs from fifty human cadavers (30 female and 20 male) fixed in 10% formalin solution. RESULTS: The coracobrachialis muscle was found in all individuals, and the CBL muscle was present in 11%, i.e. 11 upper limbs: four women, and seven men; five left and six right. Significantly, in all cadavers in which the coracobrachialis longus was found, its presence was unilateral (five left and six right). A new classification of the CBL can be proposed based on its insertion: Type I characterized by a distal attachment located on the medial epicondyle (73% of all cases of the CBL) and Type II by an insertion into the olecranon (27% of all cases of the CBL). CONCLUSION: The CBL muscle is morphologically variable. More studies focused on the course of this muscle among various populations are needed. Nevertheless, our findings indicate that the CBL muscle could be classified as a distinct muscle.