Interstitial high dose rate brachytherapy boost in early-stage breast cancer: deformable image registration for defining target volume

Purpose: optimization of the technique of additional irradiation of the removed tumor bed using high-dose brachytherapy for breast cancer. Material and Methods: the results of treatment of 28 patients diagnosed with breast cancer were analyzed. After surgical treatment and a course of external radiation therapy, all patients underwent additional irradiation of the removed tumor bed using high-dose brachytherapy. The assessment of the operation protocols, the data of the pathomorphological conclusion was carried out, and on the basis of pre- and postoperative CT images, the formation of irradiation fields for high-dose brachytherapy was carried out. Results: After deformable (nonrigid) registration of pre- and postoperative CT images of 28 patients, it was revealed that in 18 women (64.3% of cases) the location of interstitial markers and the primary tumor focus does not match topographically, which can cause incorrect formation of borders irradiation. In 35.7% of cases, radiopaque markers were located on the chest wall (on the pectoralis major muscle) when the primary tumor was located in the breast tissue. In 25% of cases, the markers were located cranial or caudal to the topography of the primary tumor focus. Label migration occurred in 3.6% of cases. In 35.7% of cases, the topography of the primary tumor node and marks completely coincided. Conclusions: The use of deformable (non-rigid) registration of pre- and postoperative CT images is a simpler method to determine the topography of the removed tumor bed, which subsequently leads to a more accurate formation of the clinical volume of irradiation.

Partial monopolar transfer of pectoralis major for elbow active flexion restoration in children with arthrogryposis

BACKGROUND: One of the main problems that limited or made the self-ability of patients with arthrogryposis impossible is the lack of active elbow flexion due to hypoplasia (or aplasia) of the forearm flexors and, especially the m. biceps brachii. AIM: To evaluate the possibility of active forearm flexion restoration in children with arthrogryposis by partial monopolar transposition of the pectoralis major muscle. MATERIALS AND METHODS: Elbow active flexion restoration by partial monopolar transposition of the pectoralis major muscle to biceps brachii was conducted in 34 children with arthrogryposis (39 upper limbs) from 2011 to 2020. The muscle autograft included a fragment of the fascia of the m. rectus abdominis. Clinical examinations of patients were performed before and after the operation. Statistical data processing was performed using the software packages Statistica 10 and SAS JMP 11. RESULTS: The follow-up results were estimated from 6 to 99 months (44.53 31.72) postoperative. The mean age of patients was 6.24 4.24 years. The active postoperative elbow motion was 0120 (71.94 33.40). The passive postoperative elbow motion did not change and was 90130 (104.12 12.40). Muscles strength after the operation was grade 25. Elbow extension was limited in 30 cases (76.9%) from 0 to 40 (21.70 12.27) without problem in the activities of daily living. Good results were determined in 15 cases (38.5%), satisfactory in 8 (20.5%), and poor in 16 (41%). CONCLUSIONS: This study revealed that our partial monopolar transfer of pectoralis major to biceps brachii technic restored sufficient forearm flexion and improved self-ability without forming severe elbow flexor contractures of more than half of the patients with arthrogryposis.

Dynamic Spatial Tuning Patterns of Shoulder Muscles with Volunteers in a Driving Posture

Computational human body models (HBMs) of drivers for pre-crash simulations need active shoulder muscle control, and volunteer data are lacking. The goal of this paper was to build shoulder muscle dynamic spatial tuning patterns, with a secondary focus to present shoulder kinematic evaluation data. 8M and 9F volunteers sat in a driver posture, with their torso restrained, and were exposed to upper arm dynamic perturbations in eight directions perpendicular to the humerus. A dropping 8-kg weight connected to the elbow through pulleys applied the loads; the exact timing and direction were unknown. Activity in 11 shoulder muscles was measured using surface electrodes, and upper arm kinematics were measured with three cameras. We found directionally specific muscle activity and presented dynamic spatial tuning patterns for each muscle separated by sex. The preferred directions, i.e. the vector mean of a spatial tuning pattern, were similar between males and females, with the largest difference of 31° in the pectoralis major muscle. Males and females had similar elbow displacements. The maxima of elbow displacements in the loading plane for males was 189 ± 36 mm during flexion loading, and for females, it was 196 ± 36 mm during adduction loading. The data presented here can be used to design shoulder muscle controllers for HBMs and evaluate the performance of shoulder models.

Anatomical Variability of Fascial-Muscle Formations of the Thorax in 4-6-Month Human Fetuses

The development of rational accesses and methods of surgical interventions to the chest walls, muscles and vascular-nerve formations of the chest involves clarifying data on the topography of fascia, superficial and deep muscles of the chest at different stages of human ontogenesis. The purpose of the study. Identification of macromicroscopic structure and topography of fascia and chest muscles in 4-6-month human fetuses. Materials and methods. The study was performed using microscopy of a series of consecutive histological sections of 29 human embryos of 81.0-230.0 mm parietal-coccygeal length, production of three-dimensional reconstruction models and morphometry. Results and discussion. In some early fetuses, and in isolated cases in the same fetus, there is anatomical variability of the pectoralis major muscle, characterized by asymmetry of shape, size and topography of individual parts of the right and left pectoralis major muscles. The underdevelopment of the individual muscle bundles of the sternocostal part of the pectoralis major muscle, hypoplasia of the internal intervertebral muscles, aplasia of the external intercostal membrane, internal intercostal and subcostal muscles, transverse muscles of the chest is described. Conclusion. In human fetuses of 4-6 months old there is anatomical variability of the chest muscles, characterized by bilateral asymmetry, variability of shape, size and topography of both their individual parts and muscle as a whole. In early human fetuses, thoracic fascia is a rather thin structural plate, in the structure of which there is no layering. Intervertebral spaces at the level of rib cartilage are filled with internal intervertebral muscles, the fibers of which near the edges of the thorax have a vertical direction, and from the point of connection of the rib cartilage to the thorax – oblique. In the gap between the external and internal intervertebral muscles of fascia as such is not manifested, but only a small layer of loose fiber is determined, in which the vascular-nerve bundles pass. In the fetuses of 6 months, the endothorаcic fascia on the posterior wall of the chest is somewhat thickened, split into separate plates and forms fascial cases for vascular-nerve formations located near the spinal column

Force production and muscle activation during partial vs. full range of motion in Paralympic Powerlifting

Paralympic Powerlifting is a sport in which the strength of the upper limbs is assessed through bench press performance in an adapted specific bench. It is therefore essential to optimize training methods to maximize this performance. The aim of the present study was to compare force production and muscle activation involved in partial vs. full range of motion (ROM) training in Paralympic Powerlifting. Twelve male athletes of elite national level in Paralympic Powerlifting participated in the study (28.60 ± 7.60 years of age, 71.80 ± 17.90 kg of body mass). The athletes performed five sets of 5RM (repetition maximum), either with 90% of 1RM in full ROM or with a load of 130% 1RM in partial ROM. All subjects underwent both exercise conditions in consecutive weeks. Order assignment in the first week was random and counterbalanced. Fatigue index (FI), Maximum Isometric Force (MIF), Time to MIF (Time) and rate of force development (RFD) were determined by a force sensor. Muscle thickness was obtained using ultrasound images. All measures were taken pre- and post-training. Additionally, electromyographic signal (EMG) was evaluated in the last set of each exercise condition. Post-exercise fatigue was higher with full ROM as well as loss of MIF. Full ROM also induced greater. EMG showed greater activation of the Clavicular portion and Sternal portion of pectoralis major muscle and lower in the anterior portion of deltoid muscle when full ROM was performed. Muscle thickness of the pectoralis major muscle increased post-exercise. We concluded that training with partial ROM enables higher workloads with lower loss of muscle function.