Surgical and Radiologic Anatomy最新文献

{"title":"Accessory posterior cerebral artery-posterior cerebral artery anastomosis located just distal to the P1-P2 junction incidentally diagnosed by magnetic resonance angiography.","authors":"Akira Uchino","doi":"10.1007/s00276-026-03958-z","DOIUrl":"10.1007/s00276-026-03958-z","url":null,"abstract":"<p><strong>Purpose: </strong>To describe a case of an accessory posterior cerebral artery (PCA)-PCA anastomosis located just distal to the P1-P2 junction.</p><p><strong>Methods: </strong>A 73-year-old man underwent cranial magnetic resonance (MR) angiography using a 1.5-Tesla scanner. MR angiography was performed using a standard three-dimensional (3D) time-of-flight technique.</p><p><strong>Results: </strong>Maximum-intensity-projection (MIP) MR angiography showed no pathological arterial lesions. However, the parieto-occipital branch of the right PCA arose from the internal carotid artery (ICA). On MR angiographic source images, a tiny posterior communicating artery (PCoA) arose from the ICA just proximal to the origin of this anomalous artery, indicating that the anomalous artery represented an accessory PCA. Partial MIP images demonstrated a short anastomotic channel between the accessory PCA and normally originating right PCA that supplying the temporal branch located just distal to the P1-P2 junction.</p><p><strong>Conclusion: </strong>The author reports a case of a congenital short anastomosis between an accessory PCA and the PCA. The accessory PCA most frequently supplies the temporal branch of the PCA; however, in the present case, it supplied the parieto-occipital branch. Although an accessory PCA-PCA anastomosis at the distal P2 segment has previously been reported, the present case demonstrated an anastomosis just distal to the P1-P2 junction. Careful observation of MR angiographic source images is useful for identifying tiny arteries that are not visible on MIP images. Generation of partial MIP images is also valuable for detecting arterial variations.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148686329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The supraspinatus fascia: a consistently two-layered structure with nociceptive innervation and differential functional anatomy.","authors":"Lara Herrmann, Charlotte Kulow, Pierre Hepp, Hanno Steinke","doi":"10.1007/s00276-026-03949-0","DOIUrl":"10.1007/s00276-026-03949-0","url":null,"abstract":"<p><strong>Purpose: </strong>Pain in the scapular region is a common musculoskeletal complaint, yet its anatomical basis often remains unclear. This study investigates the supraspinatus fascia as a potential contributor to shoulder pain, with particular emphasis on its surgical relevance.</p><p><strong>Method: </strong>A total of 24 body donors were examined using dissection and histological analysis to characterize the fascia's morphology, topography, and neurovascular features.</p><p><strong>Results: </strong>The supraspinatus fascia consistently demonstrated a distinct two-layered architecture. Both layers showed considerable interindividual variability, ranging from thin and translucent to dense and collagen rich. There is an interposed fat layer between the superficial and deep fascial layer suggesting a potential sliding interface. The fascia forms a tubular sheath around the supraspinatus muscle, attaching to the margins of the supraspinatus fossa as well as the superior transverse scapular ligament, clavicle, and coracoid process. The deep layer is continuous with the subacromial bursa and the posterior origin of the supraspinatus muscle. In contrast, the superficial layer integrates into surrounding fascial systems, including connections to the fasciae of the levator scapulae and rhomboid minor muscles. Histological analysis identified neurovascular bundles within and traversing both fascial layers. A subset of nerve fibres showed substance P immunoreactivity, supporting a nociceptive role of the supraspinatus fascia.</p><p><strong>Conclusion: </strong>The supraspinatus fascia is a complex structure rather than a passive wrapping. Its distinct two-layered architecture and substance P-positive innervation provide an anatomical basis for idiopathic scapular pain. Clinically, the deep layer's continuity with the subacromial bursa suggests that inadequate fascial release during subacromial decompression may lead to persistent symptoms. Finally, the superficial layer's connection to the \"levator-rhomboid-minor-fascia\" establishes a myofascial bridge for force transmission, suggesting that \"shoulder pain\" could be a manifestation of cervicoscapular fascial tension.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13415671/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148609446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The infraorbital vein: embryology, anatomy, histology, variations, and clinical relevance.","authors":"Kazuaki Hasegawa, Yohei Takeshita, Shogo Kikuta, Seiichi Inoue, Mi-Sun Hur, Tatsuo Okui, R Shane Tubbs, Joe Iwanaga","doi":"10.1007/s00276-026-03951-6","DOIUrl":"10.1007/s00276-026-03951-6","url":null,"abstract":"<p><p>The infraorbital vein (IOV) is a small but clinically important component of the deep midfacial venous system, linking the infraorbital region, orbit, and infratemporal fossa. Despite its close association with the infraorbital nerve and artery, the IOV remains inconsistently described and systematically undercharacterized in the literature. This narrative review synthesizes current evidence on the embryology, anatomy, variations, and clinical relevance of the IOV to provide a clinically oriented framework. Embryologically, the IOV derives primarily from the primitive maxillary vein, with variable contributions from the orbitonasal venous channels, which explains its dual connections to the pterygoid venous plexus and the orbital venous system. Anatomically, it demonstrates considerable variability in presence, caliber, and spatial relationship within the infraorbital canal. The IOV may present as a single trunk, duplicated channels, or a plexiform network, with additional variation associated with accessory infraorbital foramina and emissary connections. Clinically, the IOV is relevant to orbital floor and zygomatic fracture repair, implant surgery, the spread of odontogenic infection, and esthetic procedures. Although often overlooked, the IOV represents a key component of a dynamic midface-orbit-skull base venous axis. Improved understanding of its anatomy and variation is essential for surgical planning and complication avoidance.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13400481/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148585640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiographic overall linearity of the forearm.","authors":"Thomas Daoulas, Olivier Bozon, Michel Chammas, Louis Lancelle, Cyril Lazerges, Bertrand Coulet","doi":"10.1007/s00276-026-03952-5","DOIUrl":"10.1007/s00276-026-03952-5","url":null,"abstract":"<p><strong>Introduction: </strong>This study aimed to describe a radiographic parameter for assessing forearm alignment based on the angular relationship between three anatomical axes on standard radiographs. We aimed to quantify the angular deviation between the radial neck axis, the ulnar diaphyseal axis, and the forearm rotation axis in healthy adults.</p><p><strong>Material and methods: </strong>A single-center observational study included 50 adults with no history of upper limb trauma or forearm pathology. Standardized bilateral anteroposterior radiographs were obtained in neutral position and full supination. Three axes were defined: the forearm rotation axis (AB axis), the ulnar axis (U axis), and the radial neck axis (R axis). Two angles (α and β) were measured, and their sum defined the Overall Linearity of the Forearm (OLF). Measurements were performed by two independent observers. Reproducibility was assessed using intraclass correlation coefficients and agreement using Bland-Altman analysis.</p><p><strong>Results: </strong>In neutral position, the median OLF was 2.9°, with an interquartile range of 1.02-4.47. In full supination, the median OLF was 3.2°, with an interquartile range of 1.92-4.7. Right-left correlation within the same volunteer was r = 0.75 in neutral position and r = 0.61 in supination. Inter-observer reliability was good, with ICC values of 0.805 in neutral position and 0.821 in supination. Bland-Altman analysis showed a mean bias of 0.37°, with limits of agreement ranging from - 0.34° to 1.07°.</p><p><strong>Conclusion: </strong>The Overall Linearity of the Forearm provides a reproducible radiographic parameter describing the angular alignment of three forearm axes on standard anteroposterior views. Further studies are required to determine its relevance in pathological conditions.</p><p><strong>Level of evidence: </strong>IV.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148585568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional morphology of the iliopsoas notch: limited association with acetabular and coxal dimensions.","authors":"Eda Duygu Ipek, Emrehan Sahin Yagmur","doi":"10.1007/s00276-026-03950-7","DOIUrl":"10.1007/s00276-026-03950-7","url":null,"abstract":"<p><strong>Purpose: </strong>The present study aimed to investigate the relationship between iliopsoas notch morphology and acetabular and coxal morphometric parameters in adult hip bones. Specifically, we sought to determine whether iliopsoas notch morphology is associated with overall pelvic dimensions or represents a localized, functionally adapted anatomical structure.</p><p><strong>Methods: </strong>A total of 184 adult dry hip bones (108 female, 76 male) were analyzed. Standard acetabular and coxal morphometric parameters were recorded, including acetabular diameters, depth, and pelvic dimensions. Iliopsoas notch width (INW), depth (IND), and morphology (curved, angular, irregular, straight) were assessed. Group comparisons and correlation analysis were performed to evaluate relationships between notch morphology and acetabular and coxal measurements.</p><p><strong>Results: </strong>Most acetabular and coxal parameters demonstrated significant sexual dimorphism (p < 0.001), whereas acetabular notch width showed no sex difference (p = 0.85). The curved type was the predominant iliopsoas notch morphology (70.1%). Significant differences among notch types were observed only for transverse acetabular diameter, INW, and IND. Correlation analysis revealed strong internal relationships among acetabular parameters (r > 0.79), but only weak to moderate correlations between notch dimensions and acetabular or coxal measurements (r = 0.185-0.422). A strong correlation was observed between INW and IND (r = 0.75, p < 0.001).</p><p><strong>Conclusion: </strong>The iliopsoas notch demonstrates limited association with global acetabular and pelvic dimensions, suggesting greater influence from localized anatomical and biomechanical factors than from overall pelvic scaling. These findings have implications for understanding iliopsoas-related pathologies and optimizing acetabular component positioning in total hip arthroplasty.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148474029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validity and reliability of intraoral ultrasonography for the assessment of human periodontal structures.","authors":"Su-Jeong Kim, Kyu-Lim Lee, Jiong-Zhen Piao, Kyung-Seok Hu, Hee-Jin Kim","doi":"10.1007/s00276-026-03934-7","DOIUrl":"10.1007/s00276-026-03934-7","url":null,"abstract":"<p><strong>Purpose: </strong>Recent advances in intraoral ultrasonography (US) have enabled quantitative evaluation of periodontal tissues; however, limitations regarding applicable measurement sites and structural visualization remain. This study aimed to investigate the anatomical accuracy and measurement reproducibility of intraoral US imaging for soft and hard periodontal tissues, comprising buccal and lingual palatal surfaces and dental calculus.</p><p><strong>Methods: </strong>US images were captured from the gingival margin (GM), alveolar bone crest (ABC), and cementoenamel junction (CEJ) of 108 teeth from fixed human cadavers. These regions were sectioned and scanned to generate reference images. Three parameters were measured: (1) the distance between the ABC and GM, (2) the distance between the ABC and CEJ, and (3) the linear length of the dental calculus on the tooth surface. Three independent examiners performed all measurements twice for reliability analysis.</p><p><strong>Results: </strong>US images clearly delineated the gingiva, CEJ, alveolar bone, and calculus based on their echogenic characteristics. No statistically significant differences were observed between the US and reference measurements (p > 0.05). Intraclass correlation coefficients ranged from 0.78 to 0.97 for intra-rater and 0.92 to 0.96 for inter-rater reliability. Bland-Altman analysis revealed 95% limits of agreement of - 0.27 to 0.94 mm for ABC-GM, - 0.28 to 1.12 mm for ABC-CEJ, and - 0.22 to 0.81 mm for calculus length. These findings confirm that intraoral US reliably represents anatomical structures with high fidelity.</p><p><strong>Conclusion: </strong>US is a valid, reproducible modality for evaluating ABC, GM, CEJ, and calculus across buccal and lingual surfaces, providing a standardized anatomical foundation.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148457587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Layer-specific neuroanatomical architecture of the quadratus lumborum: a quantitative study using 3D micro-CT and immunofluorescence staining.","authors":"Hyung-Jin Lee, Soo-Jung Kim, Jisu Lee, In-Seung Yeo","doi":"10.1007/s00276-026-03936-5","DOIUrl":"10.1007/s00276-026-03936-5","url":null,"abstract":"<p><strong>Purpose: </strong>The quadratus lumborum (QL) is increasingly recognized as an anatomically important component of the posterior abdominal wall, yet its internal organization remains incompletely defined. This study aimed to characterize the layer-specific architecture of the QL and to quantitatively analyze the distribution of immunolabeled axonal components across its layers.</p><p><strong>Methods: </strong>Ten embalmed adult cadavers (mean age, 82.1 ± 9.9 years) were examined. Gross dissection and morphometric analysis were performed in eight cadavers (16 sides) to identify layer-specific organization and measure width and thickness at standardized anatomical landmarks; measurement reliability was assessed using intraclass correlation coefficients. Non-destructive three-dimensional reconstruction was performed in four phosphotungstic acid-enhanced block specimens using micro-computed tomography (micro-CT; voxel size, 72 μm). Histological and immunofluorescence analyses were performed in six sides using Masson's trichrome staining and double labeling for NF200 combined with choline acetyltransferase (ChAT), tyrosine hydroxylase (TH), or calcitonin gene-related peptide (CGRP). Marker-positive axons were quantified relative to NF200-positive axons.</p><p><strong>Results: </strong>Gross dissection and micro-CT consistently demonstrated a three-layer organization of the QL, comprising the lumbocostal (LC), iliocostal (IC), and iliolumbar (IL) layers. Morphometrically, the LC was the smallest layer, the IC was the thickest, and the IL was the widest. Neural branches arose mainly from the ventral rami of T12-L4 and entered the muscle along its anterior and lateral aspects as neurovascular bundles. Intramuscular nerves were multifascicular, and mean axonal diameter was greatest in the IC (572.9 ± 41.8 μm) and IL (556.1 ± 38.4 μm) and smallest in the LC (276.9 ± 65.2 μm). Immunofluorescence analysis demonstrated layer-dependent differences in marker distribution: the IC showed the highest proportions of ChAT-positive (26.4%) and TH-positive (32.4%) axons, whereas the LC showed the highest proportion of CGRP-positive axons (24.5%). The IL showed lower proportions of ChAT-, TH-, and CGRP-positive axons and the highest residual NF200-positive fraction (39.7%).</p><p><strong>Conclusion: </strong>The quadratus lumborum is a reproducible multilayered structure with layer-specific morphometric and immunolabeled neural heterogeneity. These findings provide quantitative anatomical evidence of layer-specific structural and neuroanatomical heterogeneity within the quadratus lumborum.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148457604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating knowledge acquisition, confidence, and cognitive workload in immersive virtual reality anatomy education: a prospective study of medical students.","authors":"Christopher M Ahmad, Ambrose Loc Ngo, Rae-Anne Kastle, Phil Sheridan, Uyen Tam Nguyen, Melissa Zolnierz","doi":"10.1007/s00276-026-03942-7","DOIUrl":"10.1007/s00276-026-03942-7","url":null,"abstract":"<p><strong>Background: </strong>Immersive virtual reality (VR) allows learners to interact with anatomical structures in three dimensions, potentially improving spatial understanding compared to traditional instructional methods. While VR is increasingly incorporated into medical curricula, prospective studies evaluating both learning outcomes and experiential measures remain limited. This study aimed to evaluate the impact of a single immersive VR anatomy session on knowledge acquisition, learner confidence, cognitive workload, and perceived immersion among first-year medical students.</p><p><strong>Methods: </strong>In this prospective educational intervention, first-year medical students at Kansas City University completed a standardized immersive VR anatomy module. Anatomy knowledge was assessed using a 20-item multiple-choice examination administered pre-session, immediately post-session, and at a 20-day follow-up. Learner confidence was measured using a 5-point Likert scale. Cognitive workload was assessed using the NASA Task Load Index (NASA-TLX), and immersion was measured using validated presence and usability items.</p><p><strong>Results: </strong>Anatomy knowledge improved significantly from pre- to post-intervention (mean increase 7.2% points, 95% CI [3.9, 10.6], p < 0.001). However, scores declined at delayed follow-up (mean change - 15.3% points from post, 95% CI [-19.8, -10.7], p < 0.001), falling below baseline mean levels. Confidence demonstrated a significant upward shift in distribution (p = 0.018), although change in confidence was not associated with knowledge gain (p = 0.863). Cognitive workload was not significantly associated with learning outcomes, while small negative correlations were observed between knowledge gain and both presence (r = -0.31, p = 0.022) and usability (r = -0.28, p = 0.034).</p><p><strong>Conclusion: </strong>Immersive VR produces significant short-term improvements in anatomy knowledge and learner confidence but does not sustain retention following a single exposure. While effective for enhancing short-term anatomy knowledge and learner engagement, these findings suggest that immersive VR may be most effective when integrated as a complementary component within a multimodal anatomy curriculum rather than used as a standalone instructional modality.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148450191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new classification system of superior and inferior gemelli muscles: a cadaveric study.","authors":"Nicol Zielinska, George Triantafyllou, Andrzej Borowski, Bartosz Gonera, Bartłomiej Szewczyk, Adrian Balcerzak, Łukasz Olewnik","doi":"10.1007/s00276-026-03941-8","DOIUrl":"10.1007/s00276-026-03941-8","url":null,"abstract":"<p><strong>Background: </strong>The superior and inferior gemellus muscles are small components of the deep gluteal region that contribute to lateral rotation and stabilization of the hip joint. Despite their functional importance, these muscles display notable morphological variability with potential clinical relevance. The aim of this study was to classify the morphological variations of the superior and inferior gemellus muscles observed during anatomical dissection.</p><p><strong>Materials and methods: </strong>A total of 60 lower limbs (28 male lower limbs and 32 female lower limbs; 30 right and 30 left) from 30 cadavers of a Central European population, fixed in a 10% formalin solution, were examined.</p><p><strong>Results: </strong>Upon dissection, the morphology of the superior and inferior gemellus muscles was assessed. Based on their course and the number of muscle bellies, four types of the superior gemellus muscle and three types of the inferior gemellus muscle were identified. The superior gemellus muscle was present in 86.7% of cases and the following types were distinguished: Type 1 (65%) was characterized by a single belly proximally attached to the external surface of the ischial spine and distally attached to the trochanteric fossa. Type 2 (10%) consisted of a double belly arising as a common muscular mass from the external surface of the ischial spine; the upper belly was distally fused with the piriformis tendon and attached to the tip of the greater trochanter, whereas the lower belly was distally attached to the trochanteric fossa of the femur. Type 3 (11.7%) presented as a single belly proximally attached to the external surface of the ischial spine and fusing with the piriformis muscle tendon. Their common tendon was distally attached to the tip of the greater trochanter. Type 4 (13.3%) was characterized by the absence of the superior gemellus muscle. The inferior gemellus muscle was present in 80% of cases and following types were identified: Type I (75%) consisted of a single belly proximally attached to the upper part of the ischial tuberosity and distally attached to the trochanteric fossa. Type II (5%) showed a double belly proximally attached to the upper part of the ischial tuberosity, fusing into a common muscular mass and distally attached to the trochanteric fossa. Type III (20%) - characterized by the absence of the inferior gemellus muscle.</p><p><strong>Conclusions: </strong>The superior and inferior gemellus muscles demonstrate considerable morphological variability. Knowledge of these variations is essential for clinicians involved in diagnostic imaging, surgical procedures, and the management of neurovascular compression syndromes.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13372999/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148450136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A rare subtype of the extensor digitorum brevis manus muscle: description and clinical relevance.","authors":"Mateus Lacerda de Souza, Josemberg da Silva Baptista","doi":"10.1007/s00276-026-03947-2","DOIUrl":"10.1007/s00276-026-03947-2","url":null,"abstract":"<p><strong>Objective: </strong>The extensor digitorum brevis manus (EDBM) is an infrequent anatomical variation on the dorsum of the hand, with an estimated prevalence of 2%. Morphologically, type III is the rarest variant. The purpose of this study is to provide a detailed morphological description of a rare specimen of the EDBM, classified as type III, and to analyze its biomechanical implications and clinical relevance in the differential diagnosis.</p><p><strong>Materials and methods: </strong>A meticulous anatomical dissection was performed on the dorsal surface of the left hand of a male cadaver. Morphometric analysis was conducted using a digital caliper to record the precise dimensions of the muscle belly and its associated tendon.</p><p><strong>Results: </strong>An accessory muscular structure was identified deep to the tendons of the extensor digitorum muscle, located medially to the extensor indicis muscle. The muscle originated from the dorsal radiocarpal ligament at the distal portion of the radius and inserted into the medial margin of the extensor expansion of the middle finger. This configuration corresponds to the type III variant by Ogura et al., which represents the rarest variant described in the literature.</p><p><strong>Conclusions: </strong>The EDBM is a significant anatomical variation often misdiagnosed as a ganglion or synovial cyst due to lack of awareness among clinicians. Understanding its rarest subtypes, such as type III, is essential for improving clinical practices and surgical management thereby enhancing the quality of life for symptomatic patients.</p>","PeriodicalId":49461,"journal":{"name":"Surgical and Radiologic Anatomy","volume":"48 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13372991/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148457523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}