The EOS is a medical imaging system that incorporates simultaneous orthogonal images, producing three-dimensional (3D) reconstructions of the whole skeletal system in various functional positions. ...Despite growing interest in the pelvic 3D position, the validity of the EOS has not yet been well studied. We investigated the trueness and precision of EOS imaging for pelvic parameters and orientation and assessed whether the measurement using the EOS was affected by the pelvic orientation itself. The orientation of the anterior pelvic plane and pelvic parameters of a custom-made pelvic phantom were measured by three raters using the EOS, and the measurements obtained were compared with the true values. The standard deviations of the measurement errors were 3.23°, 0.26°, 0.23°, 2.98°, 0.88°, and 3.22° for flexion, obliquity, rotation, pelvic incidence, spinopelvic tilt, and sacral slope, respectively. The root-mean square averages of the standard deviation of each measurement were 4.05°, 0.41°, 0.28°, 4.80°, 0.99°, and 5.13°, respectively. The measurement errors for sacral slope correlated significantly with geometric means of flexion, obliquity, and rotation (r = 0.364, p = 2.67 × 10
). The EOS rendered accurate and reliable measurements regarding pelvic 3D position, even with positional variation, but positional variation could affect measurements of sacral slope.
Extant archosaurs exhibit highly divergent articular soft tissue anatomies between avian and crocodilian lineages. However, the general lack of understanding of the dynamic interactions among ...archosaur joint soft tissues has hampered further inferences about the function and evolution of these joints. Here we use contrast‐enhanced computed tomography to generate 3D surface models of the pelvis, femora, and hip joint soft tissues in an extant archosaur, the American alligator. The hip joints were then animated using marker‐based X‐Ray Reconstruction of Moving Morphology (XROMM) to visualize soft tissue articulation during forward terrestrial locomotion. We found that the anatomical femoral head of the alligator travels beyond the cranial extent of the bony acetabulum and does not act as a central pivot, as has been suggested for some extinct archosaurs. Additionally, the fibrocartilaginous surfaces of the alligator’s antitrochanter and femoral neck remain engaged during hip flexion and extension, similar to the articulation between homologous structures in birds. Moreover, the femoral insertion of the ligamentum capitis moves dorsoventrally against the membrane‐bound portion of the medial acetabular wall, suggesting that the inner acetabular foramen constrains the excursion of this ligament as it undergoes cyclical stretching during the step cycle. Finally, the articular surface of the femoral cartilage model interpenetrates with those of the acetabular labrum and antitrochanter menisci; we interpret such interpenetration as evidence of compressive deformation of the labrum and of sliding movement of the menisci. Our data illustrate the utility of XROMM for studying in vivo articular soft tissue interactions. These results also allow us to propose functional hypotheses for crocodilian hip joint soft tissues, expanding our knowledge of vertebrate connective tissue biology and the role of joint soft tissues in locomotor behavior.
We assessed the kinematic relationship of hip joint soft tissues in the American alligator during the high walk using XROMM and DiceCT techniques. Repeated kinematic patterns allow interpretation of a non‐pivoting femoral head, engagement between the femoral neck and antitrochanter, ligament movement, as well as labrum compression. These results allow us to propose functional hypotheses of crocodylian joint tissues and expand our knowledge on the role of vertebrate joint tissues.
Biomechanical testbench emulating the physiological loading of the pelvis is crucial in developing reconstructive implants for fragility fractures of the pelvis. Additionally, it will help understand ...the influence of the common daily loading on the pelvic ring. However, most reported experimental studies were mainly comparative with simplified loading and boundary conditions. In Part I of our study, we described the concept of the computational experiment design to design and construct a biomechanical testbench emulating the gait movement of the pelvis. The 57 muscles and joints' contact forces were reduced to four force actuators and one support, producing a similar stress distribution. The experimental setup is explained in this paper and some experimental results are presented. In addition, a series of repeatability and reproducibility tests were conducted to assess the test stand capabilities of replicating the gait physiological loading. The calculated stresses and the experimentally recorded strains showed that the pelvic ring response to the loading always follows the loaded leg side during the gait cycle. Furthermore, the experimental results of the pelvis displacement and strain at selected locations match the numerical ones. The developed test stand and the concept of computational experiment design behind it provide guidelines on how to design biomechanical testing equipment with physiological relevance.
Radiological anatomy of the abdomen Fang, Cheng; Kane, Pauline; Bazira, Peter J. ...
Surgery (Oxford),
January 2024, 2024-01-00, Letnik:
42, Številka:
1
Journal Article
Recenzirano
Advances in technology have led to significant developments in techniques for imaging the abdominal and pelvic organs, in both the elective and emergency surgical settings. Improvements in the ...quality and availability of imaging has had a profound effect on the delivery of high-quality surgical care and has improved outcomes by providing accurate preoperative diagnosis and staging, leading to a reduction in exploratory and futile operations, while permitting better planned precision surgery and a growing range of interventional radiology procedures. This article will describe the essential anatomical interpretation of the common radiological imaging techniques relevant to the abdomen and pelvis and describe the rationale for selection of the most appropriate imaging modality.
Research update, focused review.
Identify the role of the pelvis in the setting of adults with spinal deformity.
Sagittal plane alignment is increasingly recognized as a critical parameter in the ...setting of adult spinal deformity. Additionally, pelvic parameters reveal to be a key component in the regulation of sagittal alignment.
Analysis of the pelvis in the sagittal plane is commonly assessed by 3 angular measurements: the pelvic incidence (morphologic parameter directly linked to sagittal morphotypes), the pelvic tilt (or pelvis retroversion used to maintain an upright posture in the setting of spinal deformity), and the sacral slope. Recent work using force plate technology has revealed that in the setting of anterior trunk inclination ("spinal imbalance"), the pelvis shifted posteriorly (toward the heels) in order to maintain a balanced mass distribution. The complex relationship between pelvic and spinal parameter were investigated in order to construct predictive formulas of postoperative spinopelvic alignment. It has emerged that pelvic tilt is highly correlated with patient self reported function (ODI, SF-12, and SRS).
It has become evident that good clinical outcome in the treatment of spinal deformity requires proper alignment. Pelvis parameters play an essential role not only in terms of spine morphotypes but also in regulating standing balance and postoperative alignment. Thus, optimal treatment of a patient with spinal deformity requires integration of the pelvis in the preoperative evaluation and treatment plan.
Anterior pelvic ring injuries can be treated via Pfannenstiel, modified Stoppa, or ilioinguinal approaches, but these require exposing the abdominal soft tissues and may damage pelvic organs. The ...scar on the abdominal wall is also unacceptable for some patients. The minimally invasive anterior pelvic ring internal fixator (INFIX) is not ideal for thin patients with easily irritated skin, and it is associated with complications such as femoral nerve palsy, vascular occlusion, and lateral femoral cutaneous nerve injury. In this study, we designed a new external pelvic approach for the treatment of an anterior pelvic ring fracture.
We retrospectively reviewed 28 patients with 36 pubic ramus fractures that had been treated via the covert-inferior pelvic approach. All patients underwent a surgical procedure between August 2019 and January 2021. According to the Nakatani classification, there were 6 cases of type-I fracture, 25 cases of type-II fracture, and 5 cases of type-III fracture. Operative time, blood loss, and postoperative radiographic and computed tomographic (CT) findings were recorded. Patients were followed for fracture healing time, functional status, esthetic satisfaction, and complications.
A total of 27 patients had follow-up for at least 12 months (range, 12 to 29 months). Postoperative radiographs and CT scans showed well-positioned plates and screws. The mean preoperative time was 9.4 ± 3.8 days, the mean operative time was 61.3 ± 22.67 minutes, the mean intraoperative blood loss was 63.6 ± 42.62 mL, the mean fracture healing time was 4.1 ± 1.6 months, and the mean Majeed score was 89.74 ± 8.07. There were no complications of nonunion, internal fixation failure, vascular injury, nerve palsy, or hernia. All of the patients were esthetically satisfied with the scar.
The covert-inferior pelvic approach combined with a subpubic plate effectively fixed Nakatani type-I, II, and III fractures. The advantages of this method include rapid recovery after the surgical procedure, safety, simplicity, a short learning curve, no damage to abdominal soft tissue, no effect on pubic symphysis micromotion, and esthetic benefits. It may be another option for anterior pelvic ring fractures and can supplement other approaches.
Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.
Pelvic floor dysfunction has caused pain to the lives of the majority of female patients, and repeated visits to the hospital for treatment have also caused inconvenience to patients. Therefore, a ...portable pelvic floor dysfunction rehabilitation training system is designed to help female patients with personalized and private treatment. The pelvic floor dysfunction rehabilitation system realizes the independent training mode selection through the APP client, assists the pelvic floor muscle rehabilitation training through the electrical stimulation module, and can realize the recovery situation of the pelvic floor muscle strength in real time through the AD acquisition module. The experimental results show that the pelvic floor dysfunction rehabilitation training system implements bipolar electrical stimulation pulses, and the EMG signals collected at the same time clearly show the EMG signal strength and strength maintenance time.
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