The Achilles tendon (AT) is the strongest tendon of the human body. The knowledge of AT anatomy is a basic prerequisite for the successful treatment of acute and chronic lesions. The structure of the AT results from a complicated fusion of three parts: the tendons of the medial and lateral gastrocnemius and the soleus muscles. From proximal to distal, the tendon fibers twist in a long spiral into a roughly 90° internal rotation. The tendon is narrowest approximately 5-7 cm above its calcaneal insertion and from there it expands again. The topography of the footprints of the individual AT components reflects the tendon origins. The anterior (deep) AT fibers insert into the middle third of the posterior aspect of the calcaneal tuberosity, the posterior (superficial) fibers pass over the calcaneal tuberosity and fuse with the plantar aponeurosis. A deep calcaneal bursa is interposed between the calcaneal tuberosity and the AT anterior surface. The AT has no synovial sheath but is covered along its entire length with a sliding connective tissue, the paratenon which is, however, absent on its anterior surface. The AT is supplied by the posterior tibial artery (PTA) and the peroneal artery (PA). Motor innervation of the triceps surae muscle is provided by fibers of the tibial nerve which also gives off sensitive fibers for the AT. Sensitive innervation is also provided via the sural nerve. The sural nerve crosses the AT approximately 11 cm proximal to the calcaneal tuberosity. The forces acting on the AT during exercise may be up to 12 times the body weight. Physiological stretching of AT collagen fibers ranges between 2% and 4% of its length. Stretching of the tendon over 4% results in microscopic failure and stretching beyond 8% in macroscopic failure.
UNASSIGNED: Die Achillessehne (AT) ist die stärkste Sehne des menschlichen Körpers. Die Kenntnis der Anatomie der Achillessehne ist eine Grundvoraussetzung für die erfolgreiche Behandlung von akuten und chronischen Läsionen. Die Struktur dieser Sehne ergibt sich aus einer komplizierten Verschmelzung dreier Teile: der Sehnen des medialen und lateralen M. gastrocnemius und M. soleus. Von proximal nach distal verdrehen sich die Sehnenfasern in einer langen Spirale zu einer Innenrotation von etwa 90°. Die Sehne ist etwa 5‑7 cm oberhalb ihres Ansatzes am Kalkaneus am schmalsten und dehnt sich von dort aus wieder aus. Die Topographie der Footprints der einzelnen AT-Komponenten spiegelt die Sehnenursprünge wider. Die vorderen (tiefen) AT-Fasern setzen im mittleren Drittel der hinteren Seite des Tuber calcanei an, die hinteren (oberflächlichen) Fasern ziehen über den Tuber calcanei und verschmelzen mit der Plantaraponeurose. Zwischen dem Tuberculum calcanei und der vorderen Oberfläche der AT befindet sich ein tiefer Schleimbeutel (Bursa calcanei). Die AT hat keine Synovialscheide, sondern ist auf seiner gesamten Länge mit einem gleitenden Bindegewebe, dem Paratenon, bedeckt, das jedoch an seiner vorderen Oberfläche fehlt. Die AT wird von der A. tibialis posterior (PTA) und der A. peronaea (PA) versorgt. Die motorische Innervation des M. triceps surae erfolgt durch Fasern des N. tibialis, der auch sensible Fasern für die AT abgibt. Die sensible Innervation erfolgt auch über den N. suralis. Dieser suralis kreuzt die AT etwa 11 cm proximal des Tuberculum calcanei. Die Kräfte, die bei sportlicher Betätigung auf die AT einwirken, können bis zum 12-fachen des Körpergewichts betragen. Die physiologische Dehnung der Kollagenfasern der AT liegt zwischen 2 und 4% ihrer Länge. Eine Dehnung der Sehne von mehr als 4% führt zu mikroskopischem Versagen und eine Dehnung von mehr als 8% zu makroskopischem Versagen.

UNASSIGNED: Anastomotic leakage (AL) has always been one of the most serious complications of esophagectomy with gastric conduit reconstruction. There are many strong risk factors for AL in clinical practice. Notably, the tension at the esophagogastric anastomosis and the blood supply to the gastric conduit directly affect the integrity of the anastomosis. However, there has been a lack of quantitative research on the tension and blood supply of the gastric conduit. Changes in extracellular matrix collagen reflect tension and blood supply, which affect the quality of the anastomosis. This study aimed to establish a quantitative collagen score to describe changes in the collagen structure in the extracellular matrix and to identify patients at high risk of postoperative AL.
UNASSIGNED: A retrospective study of 213 patients was conducted. Clinical and pathological data were collected at baseline. Optical imaging of the \"donut\" specimen at the anastomotic gastric end and collagen feature extraction were performed. Least absolute shrinkage and selection operator (LASSO) regression models were used to select the significant collagen features, compute collagen scores, and validate the predictive efficacy of the collagen scores for ALs.
UNASSIGNED: LASSO regression analysis revealed three collagen-related parameters in the gastric donuts: histogram mean, histogram variance, and histogram energy. Based on this analysis, we established a formula to calculate the collagen score. The results of the univariate analysis revealed significant differences in the preoperative low albumin values (P=0.002) and collagen scores between the AL and non-AL groups (P=0.001), while the results of the multivariate analysis revealed significant differences in the collagen scores between the AL and non-AL groups (P=0.002). The areas under the curve (AUCs) of the experimental and validation cohorts were 0.978 [95% confidence interval (CI): 0.931-0.996] and 0.900 (95% CI: 0.824-0.951), respectively.
UNASSIGNED: The collagen score established herein was shown to be related to AL and can be used to predict AL in patients who underwent esophagectomy.

The ovaries, resembling almonds in shape and size, are vital organs that serve as the female gonads where oocytes, or female gametes, undergo development and where various reproductive hormones are produced. The ovaries receive their arterial blood supply predominately from the ovarian artery but also from the ascending branches of the uterine artery. The arterial anatomy of the ovaries is highly significant in any gynecological surgical procedure, as hemorrhagic complications may be fatal. Therefore, the main objective of the present review is to comprehensively describe the complete anatomy of the arterial blood supply of the ovaries. The arterial blood supply to the ovaries is facilitated by a complex network of arteries, frequently characterized by diverse anastomoses. Notably, the ovarian artery and uterine artery exhibit significant variability, presenting challenges for physicians performing gynecological and endovascular procedures. This study showcased comprehensive and detailed insights into the arterial blood supply of the ovaries, serving as a valuable resource for practitioners navigating the complexities of these procedures. By offering clear and detailed information, the present study aimed to enhance the effectiveness and safety of medical interventions involving the ovaries.

UNASSIGNED: The dominant artery blood supply is a characteristic of hepatocellular carcinoma (HCC). However, it is not known whether the blood supply can predict the post-hepatectomy prognosis of patients with HCC. This retrospective study investigated the prognostic value of the portal venous and arterial blood supply estimated on triphasic liver CT (as a portal venous coefficient, PVC, and hepatic arterial coefficient, HAC, respectively) in patients with HCC following hepatectomy.
UNASSIGNED: HCC patients who were tested by triphasic liver CT 2 weeks before hepatectomy and received R0 hepatectomy at the Second Affiliated Hospital, Kunming Medical University between January 1, 2016 and December 31, 2020, were retrospectively screened. Their PVC and HAC, and other variables were analyzed for the prediction of overall survival (OS) and recurrence-free survival (RFS) using the least absolute shrinkage and selection operator and Cox proportional hazard regression models.
UNASSIGNED: Four hundred and nineteen patients (53.2 ± 10.6 years of age and 370 men) were evaluated. A shorter OS was independently associated with higher blood albumin and total bilirubin grade [hazard ratio (HR) 2.020, 95% confidence interval (CI) 1.534-2.660], higher Barcelona Clinic Liver Cancer (BCLC) stage (HR 1.514, 95% CI 1.290-1.777), PVC ≤ 0.386 (HR 1.628, 95% CI 1.149-2.305), and HAC > 0.029 (HR 1.969, 95% CI 1.380-2.809). A shorter RFS was independently associated with male (HR 1.652, 95% CI 1.005-2.716), higher serum α-fetoprotein ≥ 400 ng/mL (HR 1.672, 95% CI 1.236-2.263), higher BCLC stage (HR 1.516, 95% CI 1.300-1.768), tumor PVC ≤ 0.386 (HR 1.641, 95% CI 1.198-2.249), and tumor HAC > 0.029 (HR 1.455, 95% CI 1.060-1.997).
UNASSIGNED: Tumor PVC or HAC before hepatectomy is valuable for independently predicting postoperative survival of HCC patients.

UNASSIGNED: Osteonecrosis (ON) of the humeral head is defined as \"avascular\" when the death of bone is due to a disrupted blood supply. It is a known complication following proximal humeral fractures and can lead to poor long-term outcomes and even additional revision surgeries.
UNASSIGNED: Patient AP developed symptomatic ON, 3 years following repair of a 4-part valgus impacted proximal humerus fracture. The point of interest in this case is the length of time from injury at which she developed symptomatic ON. Following surgical repair, she was seen at standard intervals, 6 weeks, 3-, 6-, and 12- month follow-ups and demonstrated an excellent recovery. By the 1 year follow-up appointment, she had obtained a range of motion in her left shoulder of 170° forward elevation and 60° in external rotation. At this point, she was able to discontinue physical therapy and was radiographically and clinically healed. However, 2 years after, she began experiencing sudden onset of pain with shoulder ROM and progressive limitation. She was diagnosed with an ON of her proximal humerus. The patient was prescribed a 3-month course of corticosteroid, 3 months following her operation for a gynecological-related issue. However, with strong progress being made 9 months after this prescription, and problems occurring over 2 years after taking the medication, it is unclear whether the ON was related to her fracture pattern or developed as a result of the corticosteroid usage or a combination of the 2 due to a \"double hit.\"
UNASSIGNED: This case review points out the potential need for continued monitoring even after radiographic and clinical healing is achieved in these injuries.

UNASSIGNED: Foot health is crucial for elephants, as pathological lesions of the feet are a leading cause of euthanasia in captive elephants, which are endangered species. Proper treatment of the feet, particularly in conditions affecting the digits and the digital cushion, requires a thorough understanding of the underlying anatomy. However, only limited literature exists due to the small population and the epidemiological foot diseases which often precludes many deceased elephants from scientific study. The aim of this study was to provide a detailed anatomical description of the blood supply to the African elephant\'s hindfoot.
UNASSIGNED: The healthy right hindlimb of a 19-year-old deceased female African savanna elephant was examined using computed tomography. Following a native sequence, 48 mL of barium-based contrast agent was injected into the caudal and cranial tibial arteries, and a subsequent scan was performed. The images were processed with 3D Slicer software.
UNASSIGNED: The medial and lateral plantar arteries run in a symmetrical pattern. They each have a dorsal and a plantar branch, which reach the plantar skin before turning toward the axial plane of the sole to reach the digital cushion from the proximal direction. An accurate 3D model of the arteries and the bones of the foot, a set of labeled images and an animation of the blood supply have been created for ease of understanding.
UNASSIGNED: In contrast to domestic ungulates, the digital cushion of the hindlimb is supplied differently from that of the forelimb. The lack of large vessels in its deeper layers indicates a slow regeneration time. This novel anatomical information may be useful in the planning of surgical interventions and in emergency medical procedures.

OBJECTIVE: Observation of pituitary neuroendocrine tumors with streaky sign on MRI, analysis of their features on imaging and further investigation of the relationship between the direction of the streak sign and the direction of optimal tumor expansion.
METHODS: The MR images of 237 patients with pituitary neuroendocrine tumors were retrospectively analyzed. The streaky-like high signal with a substantial length of more than 10 mm and obvious enhancement on T1WI was defined as the streaky sign. Finally, 66 patients were included in the study, comprising 33 patients with streaky sign pituitary neuroendocrine tumors and 33 randomly selected patients with non-streaky sign pituitary neuroendocrine tumors. The general condition of these 66 patients, the imaging features of the tumor, and the measurement and analysis of the direction of the streaky sign in relation to the direction of optimal tumor extension were observed and analyzed.
RESULTS: On MRI, 85 streaky signs were observed. The average deviation between the direction angle of all the streaky signs and the optimal extension direction angle of the tumor was approximately 11°. The longest streaky sign angle was positively correlated with the optimal extension angle of the tumor, with a correlation coefficient of 0.967.
CONCLUSIONS: The presence of a streaky sign of pituitary neuroendocrine tumors may indicate a dilated sinus or a small blood vessel. Its direction is highly consistent with the optimal extension direction of the tumor, which has a certain supporting effect on the long-distance growth of the tumor.