Anatomical Relationship Research Articles

Treatment of Posttraumatic Zygomatic Coronoid Ankylosis. Systematic Review.

Facial trauma is mostly associated with traffic accidents, fights, and sports accidents. The mandible, midface, and temporomandibular joint are usually the region's most frequently affected. Coronoid process fractures are rare, representing ∼2% of facial fractures in the literature, usually being the result of direct trauma to the zygomatic region. Due to the anatomical relationship of the coronoid process, it may be associated with other facial fractures, such as fractures of the zygomatic bone. Zygomatic-coronoid ankylosis is a rare clinical entity with variable etiology. It is most commonly associated with trauma (13%-100%), local or systemic infection (0%-53%), or systemic diseases, such as ankylosing spondylitis, rheumatoid arthritis, or psoriasis. The aim of this research is to evaluate the different treatments for ankylosis from the coronoid process to the zygoma after trauma, allowing to determine the treatment to obtain the best results. A systematic review was carried out following PRISMA "preferred reports for systematic reviews and meta-analyses" search matrix, based on a PICO question; was used PubMed, Embase, Sciencedirect, Cochrane, Google Scholar, and manual search in high-impact journals between 1946 and 2023 publications in English or Spanish, including randomized and nonrandomized clinical trials, prospective and retrospective cohort studies, case-control studies, series, and case reports. A total of 1993 articles were obtained from the 4 databases. After corroborating duplicate articles, 847 articles were excluded. Another 1112 articles were excluded in the title evaluation, and an additional 1093 after the abstract review; a total of 19 articles eligible for full-text evaluation were established and 1 article was added as a result of the manual search. After the full-text review, it was decided to include 16 articles in the study that met the objectives of the systematic review. After evaluating the different treatments described in the literature, the authors can determine that coronoidectomy through an intraoral approach is the most appropriate treatment for zygomatic coronoid ankylosis, accompanied by postoperative physiotherapy to achieve greater oral opening without recurrences.

Anatomical characteristics of the phrenic nerve and the spontaneous conduction block between the right atrium and the superior vena cava

Abstract Introduction Although the superior vena cava isolation (SVCI) with minimal radiofrequency application using a spontaneous right atrium – superior vena cava (RA-SVC) conduction block has been reported, the anatomical characteristics of the spontaneous RA-SVC conduction block is not clear. Purpose The aim of this study to evaluate the anatomical relationship between the spontaneous RA-SVC conduction block and the phrenic nerve (PN). Methods This study consisted of 73 patients who attempted to undergo SVCI using a RA-SVC conduction block. The RA-SVC conduction block was visualized using the extended early meets late tool with the CARTO3 system. We set the first lower threshold at 1800/total local activation time to optimize the visualization of spontaneous RA-SVC conduction block. If the SVC was not isolated by ablation to the gap of the visualized conduction block line, the lower threshold was increased by 5%, and the new gap was ablated each time. The course of the right PN was detected by pacing with 20 mA /2 ms. The RA-SVC conduction block and the course of the PN were measured with reference to the height of the left atrial roof. The extend of the RA-SVC conduction block and PN were measured in angles with respect to the ventral side (Figure 1). These anatomical parameters were compared between the RA-SVC block line and the PN. Results Sixty-one patients (83.6%) had spontaneous RA-SVC conduction block, and the remaining 12 patients (16.4%) did not. Anatomical characteristics were evaluated in 61 patients with spontaneous RA-SVC conduction block. Compared with the course of the PN, RA-SVC conduction block extended more posteriorly (110 degrees vs 128 degrees, P = 0.013) and more caudally (9.5 mm vs 16.1 mm, P<0.0001) (Figure 2). In the patients who underwent SVCI using a RA-SVC conduction block, any patients did not undergo radiofrequency application on the course of the PN. Conclusion Since the caudal end of the RA-SVC conduction block is posterior to the caudal end of the phrenic nerve, SVCI using the RA-SVC conduction block may be able to avoid ablation near the PN.Figure1Figure2

121 year after Einthoven: show me the normal ECG?

Abstract Background The clinical electrocardiogram (ECG) is measured about 120 years. The interpretations of the ECG is an art mastered by only few. Rhythm and Interval analysis is relative reliable and well supported by the available ECG machines. However, the interpretation of the ECG waveform and where it starts to deviate from the normal waveforms is poorly defined for the clinical practice. To support the anatomical relationship of the ECG, the PathECG has been developed as part of the CineECG tool, expanding the view on the ECG. In this study normal ECG distributions were created from a public available database to enable a) visual comparison of the ‘normality’ of the ECG and PathECG and b) build a predictive model to classify an ECG as normal or abnormal. Purpose To create an objective and 3D visual comparison of an ECGs to "normal ECGs". Methods From the (Physionet) PTB-XL database (Germany) all verified ECGs with known gender were selected. From the these ECGs a median ventricular beat was automatically constructed and subsequently resampled to have a standardized number of samples (Figure: Normal ECGs on top of abnormal ECGs). These resampled ECGs were also converted to their equivalent PathECG. From the normal labeled ECGs (3124 female, 2283 male) distributions were created, representing the normal ECG for male, female or the combined group. With these distributions a percentage of ECG segments (QRS, ST, T wave) can be identified as being outside this distribution, and thus as potentially abnormal. A logistic regression model was fitted to determine the optimal outlier removal per segment for the ECG waveforms and the PathECG to classify and ECG as normal or abnormal per gender group. The performance was tested on the CPSC (Hong Kong) public available ECG database. Results The abnormal ECG data in both databases contained approximately 1/3 normal ECG, atrial and ventricular arrhythmias and 1/3 ischemia and conduction disorders. The performance (AUC) of the logistic regression model on the PTB-XL and CPSC data respectively was MALES: 87.5% - 81.5%, FEMALES: 86.7% - 83.7%, and COMBINED: 86.8%-82.9%. The visual overlay of the ECG significantly supports the identification of abnormal segments (Figure: Normal ECG distribution example). Conclusions The overlay of an ECG and PathECG on the normal distribution supports the identification and verification of abnormal ECGs. This method might increase the ability of less experienced ECG readers, like general practitioners, to identify patients that need to be transferred to a cardiologist. This method could also be used for the classification of P-waves, paediatric ECGs or ECGs in specific patient groups.Normal ECGs on top of abnormal ECGsNormal ECG distribution example

Flow Diversion for Intracranial Aneurysms With Incorporated Branch: A Subanalysis From the SEASE International Registry

BACKGROUND The presence of an incorporated branch as well as its anatomical relationship to the intracranial aneurysms (IAs) and the parent artery may affect the occlusion outcome following flow diversion. This study evaluated the safety and effectiveness of the cobalt‐chromium Surpass Evolve (Stryker), a 64‐wire flow diversion device for the treatment of IAs with incorporated branches. METHODS This subanalysis uses data from the SEASE (Safety and Effectiveness Assessment of Surpass Evolve) registry to retrieve data related to IAs with incorporated branches. Those IAs were classified by a core lab into 4 categories based on their anatomical relationship to the parent artery and branch: (A) sidewall anatomic, (B) sidewall hemodynamic, (C) neck branch, and (D) dome branch. We compared the outcomes based on their incorporated branch's relation to the dome (A–C versus D). RESULTS This study included 67 patients and IAs. Most IAs were in the posterior communicating artery (46.3%), with a median size of 4.35 mm. Age, sex, comorbidities, baseline functional‐status, and IA features were similar between the 2 groups. Among those, 53 (79.1%) had branches emerging from the dome, and 14 (20.9%) had branches originating from other locations (A = 7, B = 2, and C = 5). At a median imaging follow‐up of 10.5 months, complete occlusion was lower in IAs with a branch from the sac compared with those with the neck (60.8% versus 92.9%; P = 0.026), with an overall occlusion of 67.7%. Thromboembolic and hemorrhagic complications, as well as retreatment, were reported in 1.6% and 3.1% of cases, respectively, with no significant differences between groups. CONCLUSION Our analysis underscores the influence of branch origin on occlusion rates, with the neck‐originating branch demonstrating higher occlusion rates. These insights emphasize the role of anatomical considerations in treatment strategies, follow‐up timelines, and designing future clinical trials. Further studies are warranted to explore these variations across different flow diversion technologies.

Some unique anatomical scaling relationships among genera in the grass subfamily Pooideae

Abstract Members of the grass family Poaceae have adapted to a wide range of habitats and disturbance regimes globally. The cellular structure and arrangements of leaves can help explain how plants survive in different climates, but these traits are rarely measured in grasses. Most studies are focused on individual species or distantly related species within Poaceae. While this focus can reveal broad adaptations, it is also likely to overlook subtle adaptations within more closely-related groups (subfamilies, tribes). This study therefore investigated the scaling relationships between leaf size, Vein Length Area (VLA), and vessel size in five genera within the subfamily Pooideae. The scaling exponent of the relationship between leaf area and VLA was -0.46 (+/- 0.21), which is consistent with previous studies. In Poa and Elymus, however, minor vein number and leaf length were uncorrelated, whereas in Festuca these traits were positively correlated (slope = 0.82 +/- 0.8). These findings suggest there are broad-scale and fine-scale variation in leaf hydraulic traits among grasses. Future studies should consider both narrow and broad phylogenetic gradients.

Three-dimensional quantitative analysis of arterial bed and elements of pelvicalyceal system of kidneys in men

The aim of the study was to investigate the patterns of three-dimensional quantitative organization of the renal artery branches in relation to the elements of the renal pelvicalyceal system in men. The study was conducted on 58 corrosion preparations of arterial vessels and renal pelvicalyceal structures obtained from men with postmortem age intervals from 22 to 75 years. As a result of the morphological study, a spatial and quantitative characteristic was given to different variants of renal artery branching, with an emphasis on their transformation into secondary vascular branches classified as zonal arteries. Additionally, a detailed analysis of the topographic and anatomical relationship between the intraorgan arterial branches of the renal artery and the excretory segments of the kidney was carried out, which made it possible to clarify the features of their spatial organization. Knowledge of the spatial arrangement of the arterial branches of the kidney, which directly correlates with the variable features of its renal pelvicalyceal apparatus and excretory system segments, opens the way to predicting potential obstacles during surgical procedures, especially during nephrolithotomy.

Ultrasound-Guided Venous Puncture Reduces Groin Complications in Electrophysiological Procedures.

Background: In electrophysiological procedures, multiple punctures on the femoral vein can be necessary depending on the number of catheters required. The femoral vein is typically located indirectly by using its anatomical relationship to the artery as a reference. However, this conventional approach can lead to significant complications, including bleeding, peri-interventional transfusion, pseudoaneurysms, or arteriovenous fistulas. Despite these risks, there is limited evidence comparing the safety of ultrasound-guided venipuncture versus the conventional technique in electrophysiological procedures. Objective: This study aimed to evaluate the impact of ultrasound-guided venipuncture on vascular access complications in electrophysiological procedures and to identify associated risk factors. Methods: In this single-center trial, patients scheduled for electrophysiological procedures at Ulm University Heart Center, Germany, were enrolled between November 2021 and October 2023. Venipuncture in the groin was performed using either the conventional or an ultrasound-guided approach. The primary composite endpoint was defined as peri-interventional major vascular access complications (Bleeding Academic Research Consortium (BARC) ≥2 bleeding, pseudoaneurysms, arteriovenous fistulas, and peri-interventional transfusion) and minor complications (BARC 1). Results: A total of 1370 patients were included: 749 in the conventional group and 621 in the ultrasound group. The primary endpoint was achieved in 19.2% of the conventional group and 12.1% of the ultrasound group (p < 0.001). An increased sheath diameter and a higher number of venous accesses were identified as risk factors for the primary endpoint. Conclusions: Ultrasound guidance for venous groin puncture in electrophysiological procedures reduces access-related complications, supporting its use with careful attention to sheath size and number.

Malignant melanotic nerve sheath tumor

Malignant melanotic nerve sheath tumor, previously known as melanotic schwannoma, is a rare variant of peripheral nerve sheath tumor composed of melanin-producing Schwann cells and clinically misdiagnosed as melanoma. Malignant melanotic nerve sheath tumor is a rare tumor with uncertain biological behavior and variable treatment recommendations. Despite the histological features that seem benign, with a low proliferation index, the clinical course of this tumor often becomes malignant, with a high frequency of local relapses and the presence of tumor metastasis signs. Distinctive features of malignant melanotic tumor of the nerve sheath are a relatively young age of patients, the presence of the Carney complex signs and psammomatous bodies in the tumor. The article presents a case of malignant melanotic tumor of the nerve sheath localized in the neck with a recurrent course. In the described clinical observation, the patient underwent surgical treatment twice. Microscopic and immunohistochemical analysis of postoperative materials gave a positive result for melanoma markers and showed the absence of psammoma bodies and low mitotic activity. The clinical course of the disease was malignant, with the appearance of a relapse in the postoperative scar. Diagnosis of malignant melanotic tumor of the nerve sheath is a complex task, both from the radiological and pathological points of view. Communication between the surgeon, radiologist and pathologist, understanding the anatomical relationships of the lesion and careful attention to the histological findings are critical to making the correct diagnosis.

Variations of the rectus capitis posterior muscles: a case report.

Duplication, accessory slips, and division of the rectus capitis posterior muscles are rare anatomical variations. Here we report a case of unilateral doubling of rectus capitis posterior major, and doubling of rectus capitis posterior minor with an accessory slip originating from the spinous process of the second cervical vertebra. The gross anatomical characteristics, clinical significance, and relationship of suboccipital musculature to the cervical myodural bridge is discussed in this report. Knowledge of rectus capitis posterior muscle variations may be of interest to clinicians practicing surgical approaches to the posterior cervical region due to the close proximity of the variations to typical muscular and neurovascular structures of the suboccipital region and potential association with the cervical myodural bridge.

Accessory Ligament of the Deep Digital Flexor Tendon of the Horse Forelimb and Its Relationship with the Superficial Digital Flexor Tendon: A Plastination, Histological, and Morphometry Study.

The accessory ligament of the deep digital flexor tendon (AL-DDFT) plays a crucial role in the stay apparatus of the horse. This study aimed to investigate the anatomical relationship between the AL-DDFT, the superficial digital flexor tendon (SDFT), and other structures in the metacarpal region. Sixteen distal forelimbs from eight horses, aged 1 to 6 years, were evaluated through macroscopic, microscopic, and morphometric analyses, utilizing detailed dissection, E12 plastinated sections, and histological analysis. During lateral dissection, a connection was observed between the AL-DDFT and the SDFT. Histological evaluation revealed that this connection was a fibrous band (FB), extending the common synovial sheath (CSS) to the SDFT, along with associated collagen fibrils of the epiligament and peritenon. Additionally, two distinct forms of the AL-DDFT were identified, Type I and Type II, with Type II showing a greater cross-sectional area (CSA) than Type I. While numerous morphological and morphometric studies have explored the AL-DDFT and related structures, research incorporating plastination-based morphological and histological evaluations remains scarce. The findings provide valuable insights for both the morphological and clinical assessment of structures within the metacarpal region.

Office-Based Digital Workflow for Managing Old Mandibular Fracture Malunion: Use of Short-Segment Drilling and Osteotomy Guides With Predictive Holes.

Treating old mandibular fractures with malunion is challenging due to the need for osteotomy and interference between bone segments, complicating occlusal restoration. This technical note introduces a novel office-based digital workflow utilizing surgical guides. Preoperative computed tomography (CT) data were imported into MIMICS software for virtual surgical planning to precisely realign bone fragments based on anatomical and occlusal relationships. A pre-bent reconstruction plate was adapted to a 3-dimensional-printed mandible model, and cone beam CT scans captured detailed screw path data. This information was used in 3-matic software to design short-segment drilling guides (SSDGs), and osteotomy guides with predictive holes. These guides facilitated accurate bone osteotomy and realignment during surgery. This workflow addresses the limitations of previous SSDGs, offering a reliable solution for managing malunion in old mandibular fractures. The approach reduces surgical complexity, enhances precision, and streamlines treatment, providing an innovative method for challenging mandibular fractures.

Assessing anatomical variations of the superior mesenteric artery via three-dimensional CT angiography and laparoscopic right hemicolectomy: a retrospective observational study.

This study aimed to analyse the anatomical relationships and differences between the superior mesenteric vessels and their branches by reviewing a laparoscopic right hemicolectomy surgery video and comparing it with preoperative three-dimensional computed tomography (3D-CT) angiography and to verify the accuracy of 3D-CT vascular reconstruction techniques. Surgical videos and preoperative imaging data of 52 patients undergoing laparoscopic right hemicolectomy were analysed to observe and summarize the probability of occurrence and adjacency of superior mesenteric vascular branches, and the lengths of specific sites of their branches were measured using the above two methods. Preoperative CT images and surgical video showed that the ileocolic artery (ICA) was present in 98.1% (51/52) and the ileocolic vein (ICV) was present in 100% (52/52), and ICA was present in 13.7% (7/51) of the ICV directly anteriorly, 13.7% (7/51) anteriorly superiorly, 3.9% (2/51) anteriorly inferiorly, 11.8% (6/51) directly posteriorly, 37.2% (19/51) post superiorly, and 19.7% (10/51) posteriorly inferiorly. In the surgical video, the probability of presence of the right colic artery (RCA) was 21.2% (11/52). On CT images, the RCA was present in 10 patients. The length of the origin of the middle colic artery (MCA) from its bifurcations was 2.33 ± 0.87 cm measured intraoperatively using a sterile isometric filament, and the length measured using 3D-CT vascular reconstruction was 2.36 ± 0.91 cm; the difference was not statistically significant (P = 0.348). The length of the MCA and ICA initiation points was 3.22 ± 0.75 cm measured intraoperatively using sterile isometric filaments and 3.36 ± 0.72 cm measured using 3D-CT vascular reconstruction, which was a statistically significant difference (P < 0.001). 3D-CT vascular reconstruction can accurately predict the vessels related to right hemicolectomy in most cases. It is an important method for preoperative prediction of superior mesenteric vessels, which can guide surgeons in the intraoperative vessel identification.

On a hunt for the "true" septocutaneous perforator - a histology cross section study.

Modern trends in reconstructive surgery involve the use of free perforator flaps to reduce the donor site morbidity. The course of perforator vessels has a great anatomic variability and demands a careful knowledge of the anatomical relationships and the variability of the course of the perforators. The numerous modifications of perforator nomenclature were proposed by many authors and brought confusion rather than a simplification. In our study we focused on a hypothesis, that septocutaneous perforator passes from the given source vessel to the deep fascia adherent to, but not to within the septum itself. 69 septocutaneous perforators from three different limb donor sites (Lateral Arm Flap, Anterolateral Thigh Flap, Radial Forearm Free Flap) were collected from gross pathology specimens of 14 fresh cadavers. The gross picture and the cross sections with the histological cross sections on different levels were examined to determine the position of vessel to the septal tissue. Of the observed 69 septal perforators, 61 (88,5%) perforators were adherent to but not within the septum. Remaining eight (12,5%) perforators passed through the septum. All these eight perforators were found in multiple different cross section levels. (two of 19 in Lateral Arm Flap, three of 27 in Anterolateral Thigh Flap, three of 23 in Radial Forearm Free Flap). Although macroscopically identical septocutaneous vessels, microscopically we observe two types of vessels - with paraseptal and intraseptal pathways. The majority are merely adherent to the septum having a paraseptal pathway. A minority are within the septum, and are "true" septocutaneous perforators. It is advisable to dissect with a piece of the septum in order to avoid damage any injury of perforator.

8182 New Mouse Model Mirrors Human MODY8: Opening Doors to Understanding Exocrine-Endocrine Crosstalk in the Diabetic Pancreas

Abstract Disclosure: K. El Jellas: None. V. Salerno: None. L.S. Katz: None. J. Hu: None. G. Fogarty: None. A. Mandal: None. A. DiStefano-Forti: None. D. Scott: None. M. Lowe: None. A. Molven: None. R.N. Kulkarni: None. Maturity-onset diabetes of the young, type 8 (MODY8) is a dominantly inherited form of monogenic diabetes, caused by heterozygous mutations in the carboxyl ester lipase (CEL) gene expressed in pancreatic acinar cells. MODY8 is characterized by chronic pancreatitis and exocrine dysfunction. Despite the intimate anatomical relationship between the endocrine and exocrine pancreas, little is known about the biological components mediating exocrine-endocrine communication in regulating glucose homeostasis. Here, we report a refined mouse model that bears the mutation present in MODY8 patients on one allele, and the humanized normal variable number of tandem repeat (VNTR) of CEL with 16 repeats (16R) on the other, mimicking the genetic make-up seen in MODY8 patients. Examination of glucose homeostasis revealed that inducing stress (e.g. by high-fat diet) leads to glucose intolerance in MODY8/16R mice and a blunted glucose-stimulated insulin-secretion compared to their control littermates. Histopathological analyses demonstrated features of chronic pancreatitis in some pancreatic lobes, including inflammation, acinar atrophy, acinar-to-ductal metaplasia, fibrosis and fat infiltration, mirroring the morphology of the human disease. Moreover, we applied immunolabeling-enabled three-dimensional imaging of solvent-cleared organs (iDISCO) to intact pancreata and found that beta-cell mass was significantly decreased in the MODY8/16R mice, with a large number of islets located within fatty lobes. These results are coupled with comparative proteomics and lipidomic profiling with the aim of understanding the molecular signatures of exocrine and endocrine cells during pathogenesis. In conclusion, we have generated a mouse that recapitulates several features of the exocrine and endocrine phenotype characteristic of human MODY8. This novel model provides a unique opportunity, not possible in humans, to characterize pancreatic endocrine-exocrine communication in a longitudinal manner as a response to diverse environmental stressors. Presentation: 6/2/2024

Zigzag tenotomy of the extensor hallucis longus through minimally invasive surgery in cadaveric specimens: description of a new technique

BackgroundLengthening of the extensor hallucis longus (EHL) is performed to address various forefoot pathologies. The retraction of this tendon is strongly associated with the Hallux Abductus Valgus (HAV) deformity. Minimally Invasive Surgery (MIS) lengthening of the EHL is carried out in combination with other surgical techniques for HAV bone realignment. It is performed without ischemia, using local anesthesia and sedation if required by the patient. One of the advantages of this technique is immediate ambulation with a postoperative shoe without the need for a cast. The objective of the research was to demonstrate the efficacy and safety of the minimally invasive technique for lengthening the tendon in patients with HAV.Materials and methodsThe procedures were performed on 11 fresh cryopreserved cadaveric feet. HAV surgery was performed through dorsomedial and dorsolateral portals for Reverdin-Isham, Akin and adductor tenotomy. In addition, EHL tendon elongation was performed using the Beaver 67 MIS scalpel through an incomplete zigzag tenotomy. The specimens used did not present any type of disease nor had they undergone previous surgeries that could affect the technique. First, the plantar flexion of the metatarsophalangeal joint was measured with a goniometer to establish the degrees of this joint before proceeding with the technique, the tenotomy was performed and remeasured and finally the osteotomy was performed. In addition, an anatomical dissection of cadaveric specimens was performed and various anatomical and surgical relationships were analyzed and measured.ResultsThe data indicate that, after performing zigzag tenotomy, there is an average improvement of 13.91 degrees in plantar flexion.ConclusionsThe study confirms the effectiveness and safety of elongating the extensor hallucis longus tendon of the hallux using minimally invasive surgery. The zigzag technique for tendon elongation may be considered a viable minimally invasive treatment option for addressing tendon hyperextension in patients with HAV.

Multi-Organ Foundation Model for Universal Ultrasound Image Segmentation with Task Prompt and Anatomical Prior.

Semantic segmentation of ultrasound (US) images with deep learning has played a crucial role in computer-aided disease screening, diagnosis and prognosis. However, due to the scarcity of US images and small field of view, resulting segmentation models are tailored for a specific single organ and may lack robustness, overlooking correlations among anatomical structures of multiple organs. To address these challenges, we propose the Multi-Organ FOundation (MOFO) model for universal US image segmentation. The MOFO is optimized jointly from multiple organs across various anatomical regions to overcome the data scarcity and explore correlations between multiple organs. The MOFO extracts organ-invariant representations from US images. Simultaneously, the task prompt is employed to refine organ-specific representations for segmentation predictions. Moreover, the anatomical prior is incorporated to enhance the consistency of the anatomical structures. A multi-organ US database, comprising 7039 images from 10 organs across various regions of the human body, has been established to evaluate our model. Results demonstrate that the MOFO outperforms single-organ methods in terms of the Dice coefficient, 95% Hausdorff distance and average symmetric surface distance with statistically sufficient margins. Our experiments in multi-organ universal segmentation for US images serve as a pioneering exploration of improving segmentation performance by leveraging semantic and anatomical relationships within US images of multiple organs.

The lumbar artery perforator free flap as an alternative option for breast reconstruction in low BMI patients: analysis of CT Angiography of donor sites across BMI.

In patients with a low body mass index (BMI), the options for autologous breast reconstruction are limited. With the hypothesis that adipose tissue deposition persists in the lumbar region compared to the abdominal wall, this study sought to investigate the lumbar artery perforator (LAP) free flap as an alternative reconstructive option in patients with deficient autologous donor sites consequent to a low BMI. A retrospective cohort analysis was performed, from a prospectively maintained database, of all consecutive DIEP flap breast reconstructions performed in our unit. A randomized selection of 100 patients with low BMI <22, normal BMI 22-24 and high BMI >30 was performed. Patient computerized tomography scans were analyzed to measure abdominal wall and lumbar tissue thickness and to define anatomical landmark relations of the lumbar artery perforator. A statistically significant difference was identified between the ratio of lumbar to abdominal wall thickness between BMI groups, highlighting preservation of the lumbar thickness in patients with low BMI. The mean distance at which the fourth lumbar perforator entered the subcutaneous tissues was 7.7cm lateral to the spinous process (range 6.4 - 9.5cm), with no significant difference between BMI groups, highlighting this consistent anatomical position. This study confirms a greater lumbar to abdominal wall thickness, therefore volume, in low BMI patients, with consistent lumbar perforator anatomy of 6.4 - 9.5cm lateral to the spinous process. The lumbar artery perforator flap should therefore be strongly considered for autologous breast reconstruction in this patients with a low BMI.

The respiratory system and associated disorders

This series of three articles will explore the fundamentals related to anatomy, physiology and pathophysiology in relation to three important topics: the cardiac system, the respiratory system and the endocrine system. This series is intended to provide an informative and evidence-based summary of each topic for both students and clinicians. This second article explores the maternal respiratory system, outlining the key physiological adaptations in pregnancy and summarises the key pathophysiological conditions that may occur.

A Cadaveric Study of the Rotator Cable: Interrogating the Suspension Bridge Model.

Purpose The objective of this cadaveric study was to describe the anatomical relationships between the rotator cuff muscles and the rotator cable. Methods In 30 formaldehyde-fixed shoulders from 20 cadavers, the rotator cuff and rotator cable were dissected and the glenohumeral joint opened. The orientation and attachments of the rotator cable to the rotator cuff muscles were described, and the severity of any osteoarthritis, labral pathology, and rotator cuff pathology present was documented. The width and thickness of the infraspinatus attachments to the rotator cable were measured. Results The infraspinatus muscle was noted to be more loosely adherent to the rotator cable, while the supraspinatus and teres minor were tightly adherent to the cable. Specifically, the superior-most portion of the infraspinatus was found to be less tightly adherent than the inferior-most portion in 26 of the 30 shoulders studied. The thickness/width ratio of the inferior-most portion of infraspinatus was significantly different in shoulders with more-than-minimal osteoarthritis and labral pathology (p=0.048 and p=0.041, respectively). Conclusion While the supraspinatus and teres minor muscles were tightly adherent to the cable in all shoulders, the degree of attachment of the superior-most portion of the infraspinatus muscle was notably less in 26 of the 30 shoulders studied. This could mean that only the inferior portion of the infraspinatus participates in stress shielding through the cable or be a compensatory response to increased load on the tendon. This work is expected to provide insight into the function of the rotator cable and the different functions of the infraspinatus.

The Suprascapular Artery as a Reference for the Evaluation of Supraspinatus Fatty Infiltration on Magnetic Resonance Imaging.

Fatty infiltration (FI) of the supraspinatus is commonly seen in chronic large-to-massive rotator cuff tears. Evaluating FI in patients with severe muscle atrophy can be confusing. The purpose of this study was to investigate the anatomic relationship between the suprascapular artery and supraspinatus muscle on magnetic resonance imaging (MRI) to provide a method for defining the border of the supraspinatus muscle on Y-view MRI. It was hypothesized that the branches of the suprascapular artery would encircle the supraspinatus muscle on Y-view and adjacent MRI slices and could be used for defining the supraspinatus outline on oblique sagittal images. Cohort study (diagnosis); Level of evidence, 3. A total of 172 shoulders that had undergone arthroscopic repair for large-to-massive rotator cuff tears were retrospectively included. Two methods, one based on the supraspinous fossa and trapezius (SF method) and the other based on the region bounded by the branches of the suprascapular artery (SA method), were used for defining the supraspinatus outline on Y-view MRI for the assessment of FI. Preoperative supraspinatus FI grade and tangent sign and postoperative tendon integrity were evaluated. Shoulder function was assessed using the American Shoulder and Elbow Surgeons (ASES) score and active range of motion. The branches of the suprascapular artery encircled the supraspinatus in all shoulders, with the diameter of the branches ranging from 0.5 to 3 mm. The agreement in supraspinatus FI grading between the SF and SA methods was 65.12%. When limited to the 61 shoulders with a positive tangent sign, the agreement dropped to 22.95% (κ = 0.032). The group (FI grade 2 by SA method and ≥3 by SF method) showed no significant difference in postoperative outcomes compared with the 2-vs-2 group but had significantly better postoperative ASES scores (P = .001) and active range of motion in forward elevation (P = .020) compared with the ≥3-vs-≥3 group. The tangent sign was positive in 92.16% of the 2-vs-≥3 group. The suprascapular artery is a reliable reference for the evaluation of supraspinatus FI. When a positive tangent sign presents, supraspinatus FI is likely to be overestimated if the hyperintensity outside the region bounded by the branches of the suprascapular artery is mistaken as FI.