Novel Anatomical Findings in Robot-Assisted Prostatectomy and Optimal Dissection Layer Selection for Preserving Urethral Support Structures.

Background: The role of preserving the superior fascia of the pelvic diaphragm in the context of urinary function remains unclear. This study aimed to investigate the anatomical relationship between the superior fascia of the pelvic diaphragm and the external urethral sphincter in terms of preventing postoperative urinary incontinence. We hypothesized that the external urethral sphincter would be supported by the fascia, smooth muscle, and levator ani muscle.

Presence of smooth muscle continuous with the rectal and vaginal walls in the deep perineal space prompts reconsideration of the deep transverse perineal muscle.

The deep transverse perineal muscle was considered a striated muscle within the deep perineal space; however, recent studies suggest that it consists of smooth muscle. We investigated the histological composition and spatial distribution of the deep perineal space and its anatomical relationships with surrounding structures to understand its role in the perineum. Perineal muscle shape and location from nine cadavers (five males; average age, 79 years) were macroscopically examined.

Pearls and pitfalls in imaging of axial spondyloarthritis for rheumatologists.

This review provides key insights into sacroiliitis imaging, covering anatomy, imaging techniques, and interpretation. It focuses on normal physiological changes in young to middle-aged women, children, and the elderly that can resemble sacroiliitis. We emphasize the importance of distinguishing between active and structural lesions, as highlighted in the recent ASAS-SPARTAN standardized magnetic resonance imaging protocol.

Three-dimensional heterogeneity of smooth muscle fiber density anterior to the rectum in males: quantitative analysis with implications for transanal total mesorectal excision.

Purpose: Transanal total mesorectal excision for rectal cancer in men poses a risk of urethral injury. The morphology of smooth muscle tissues around the rectum is reportedly characterized by differences in fiber density; however, quantitative analysis of these tissues for surgical applications is lacking. This study aimed to quantitatively analyze the histological properties of fiber density and the spatial extent of the smooth muscle anterior to the male rectum.

Anatomic Study of Hip Pericapsular Muscle Arrangement on the Joint Capsule.

Background: Despite the recognized importance of pericapsular muscles in hip stability, their specific roles in stability remain debated. For anatomically elucidating how the pericapsular muscles can act on the femoral head and neck through the joint capsule, this study aimed to investigate pericapsular muscle arrangement on the joint capsule with a positional relation to the femoral head and neck and their histological relationships.

Methods: Eight hips of 7 anatomic donors (average age, 72.

Seg and Ref: A Newly Developed Toolset for Artificial Intelligence-Powered Segmentation and Interactive Refinement for Labor-Saving Three-Dimensional Reconstruction.

Traditional three-dimensional reconstruction is labor-intensive owing to manual segmentation; this can be addressed by developing artificial intelligence-driven automated segmentation. However, it is limited by a lack of user-friendly tools for morphologists. We present a workflow for three-dimensional reconstruction using our artificial intelligence-powered segmentation tool.

Evaluating accuracy in artificial intelligence-powered serial segmentation for sectional images applied to morphological studies with three-dimensional reconstruction.

Three-dimensional (3D) reconstruction is time-consuming owing to segmentation work. We evaluated the accuracy of the artificial intelligence (AI)-based segmentation and tracking model SAM-Track for segmentation of anatomical or histological structures and explored the potential of AI to enhance research efficiency. Images [obtained via computed tomography (CT) and magnetic resonance imaging (MRI)], anatomical sections from a Visible Korean Human open resource, and serial histological section images of cadavers were obtained.

Anatomy of the distal tendinous structure of the triceps brachii: implications for the role of the triceps brachii to resist valgus elbow forces during baseball pitching.

Background: Biomechanical studies suggest that the triceps brachii muscle generates resistive force against valgus stress on the elbow during baseball pitching. However, given the parallel fiber orientation in the distal tendinous structure of the triceps brachii, the mechanism behind this anti-valgus force remains unclear. In the present study, we aimed to examine the anatomy of the distal tendinous structure of the triceps brachii using bony morphological, macroscopic, and histologic methods.

Cervical Spine Range of Motion and Sleep Disturbances in Patients With Atopic Dermatitis: A Cross-Sectional Study.

Background: Sleep disturbances are common and distressing among patients with atopic dermatitis (AD), often resulting in a cycle of worsening skin conditions. Among various factors affecting sleep in AD, cervical spine movement has been suggested to influence sleep quality; however, these studies mostly relied on subjective measures. Owing to the lack of objective and quantitative analyses of cervical spine movement, its association with sleep disturbances remains poorly understood.

In vivo movement interrelationships among the medial meniscus, joint capsule, and semimembranosus during tibial rotation.

The meniscal position within the knee is critical to maintain normal knee function. The joint capsule might dynamically coordinate the medial meniscus (MM) by transmitting a semimembranosus action. However, their interrelationships in vivo are unclear.

Elasticity assessment of flexor pronator muscles using shear wave elastography.

Background: The flexor pronator muscles (FPMs) have been thought as a dynamic stabilizer to protect the ulnar collateral ligament (UCL) from valgus stress during throwing motion. Thus, evaluation of the FPMs is important for preventing UCL injuries. Shear wave ultrasound elastography (SWE) is an imaging modality that quantifies tissue elasticity.

Elbow anatomy in perspective of joint capsule and surrounding aponeuroses: a narrative review.

Background: Because of the proximity of several ligaments, aponeuroses, and capsule in the limited area of the elbow joint, the precise anatomy is difficult to understand. In the current narrative review, we focused on two anatomical perspectives: the capsular attachment and structures consisting of ligaments.

Methods: Based on the previously performed studies regarding the elbow anatomy, a narrative review was prepared in terms of the capsular attachment and structures consisting of ligaments.

Contribution of the complex comprising the masticatory fascia, disc, and capsule to temporomandibular joint stabilization: An anatomical study.

Background: Anterior displacement of the temporomandibular joint (TMJ) disc is the most typical pathological condition of TMJ disorders. Structures attached to the articular disc may support the disc in various directions and contribute to stabilizing the TMJ. However, the relationship between the articular disc, capsule, and masticatory muscles remains unclear.

Capsular attachment on the anterosuperior femoral head-neck junction: A hypothesis about femoroacetabular impingement.

Femoroacetabular impingement (FAI), characterized by a pathological contact between the proximal femur and acetabulum, is a common precursor of hip osteoarthritis. Cam morphology is a bony prominence that causes FAI and frequently forms on the anterosuperior femoral head-neck junction. Despite anatomical consensus regarding the femoral head-neck junction as a boundary area covered by the articular cartilage and joint capsule, it remains unclear whether the joint capsule is continuous with the anterosuperior articular cartilage.

Assessing ulnar neuropathy at the elbow using magnetoneurography.

Objective: To measure neuromagnetic fields of ulnar neuropathy patients at the elbow after electrical stimulation and evaluate ulnar nerve function at the elbow with high spatial resolution.

Methods: A superconducting quantum interference device magnetometer system recorded neuromagnetic fields of the ulnar nerve at the elbow after electrical stimulation at the wrist in 16 limbs of 16 healthy volunteers and 21 limbs of 20 patients with ulnar neuropathy at the elbow. After artifact removal, neuromagnetic field signals were processed into current distributions, which were superimposed onto X-ray images for visualization.

Radiographic and clinical comparisons between loose-fit and press-fit stems in monopolar radial head arthroplasty for comminuted radial head fractures.

Purpose: Few clinical studies have compared the operative outcomes between loose- and press-fit stems in radial head arthroplasty (RHA). We aimed to evaluate the radiographic and clinical results of the two radial head implant concepts.

Methods: In this retrospective multicenter study, 32 patients (24 women and 8 men) with a mean age of 63.

Morphometric Analysis of the Tibial Attachment Shape of the Anterior Cruciate Ligament and Its Relationship With the Location of the Anterior Horn of the Lateral Meniscus.

Background: The success of anterior cruciate ligament (ACL) reconstruction relies on the accurate replication of the native ACL anatomy, including attachment shapes. The tibial attachment of the ACL exhibits significant shape variations with elliptical, C, and triangular shapes, highlighting the need for objective classification methods and additional information to identify individual anatomic variations.

Hypothesis: The location of the attachment of the anterior horn of the lateral meniscus (AHLM) may determine the shape of the ACL attachment.

In vivo interrelationships between the gluteus minimus and hip joint capsule in the hip internal rotation position with flexion.

Background: The flexion adduction internal rotation (FADIR) test is performed by the combined motions of hip flexion (with knee flexion), adduction, and internal rotation, and can often reproduce anterior hip pain consistent with an individual's presenting pain. Since it has high sensitivity for intraarticular pathology diagnosis but low specificity, understanding the extraarticular pathology that can induce anterior hip pain in the FADIR test may also be essential. This study hypothesized that the interrelationships between the joint capsule and gluteus minimus differ in individuals with and without FADIR-positive pain and aimed to elucidate the in vivo interrelationships at hip internal rotation in 90°-flexion, which is also often restricted in individuals with FADIR-positive pain.

Posteromedial capsular anatomy of the tibia for consideration of the medial meniscal support structure using a multidimensional analysis.

Medial meniscal extrusion (MME) is a structural abnormality that leads to early knee osteoarthritis; however, its formation remains debated. For anatomical consideration of the mechanism underlying MME formation, we examined the capsular attachment on the posteromedial tibia and its layered association with the semimembranosus. Fourteen knees of eight body donors were analyzed in this study; six knees were grouped for macroscopic analysis, whereas four knees each were grouped for histological and phosphotungstic acid-enhanced micro-computed tomography analyses.

Anatomical study of the bone morphology of the anterior talofibular ligament attachment.

Anterior talofibular ligament (ATFL) injuries are the most common cause of ankle sprains. To ensure anatomically accurate surgery and ultrasound imaging of the ATFL, anatomical knowledge of the bony landmarks around the ATFL attachment to the distal fibula is required. The purpose of the present study was to anatomically investigate the ATFL attachment to the fibula with respect to bone morphology and attachment structures.

A screening method for cervical myelopathy using machine learning to analyze a drawing behavior.

Early detection of cervical myelopathy (CM) is important for a favorable outcome, as its prognosis is poor when left untreated. We developed a screening method for CM using machine learning-based analysis of the drawing behavior of 38 patients with CM and 66 healthy volunteers. Using a stylus pen, the participants traced three different shapes displayed on a tablet device.