SciCombinator

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Concept: Linea alba

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Study Design Cross-sectional repeated measures. Background Rehabilitation of diastasis rectus abdominis (DRA) generally aims to reduce the inter-rectus distance (IRD). We tested the hypothesis that activation of the transversus abdominis (TrA) before a curl-up would reduce IRD narrowing, with less linea alba (LA) distortion/deformation, which may allow better force transfer between sides of the abdominal wall. Objectives This study investigated behavior of the LA and IRD during curl-ups performed naturally and with preactivation of the TrA. Methods Curl-ups were performed by 26 women with DRA and 17 healthy control participants using a natural strategy (automatic curl-up) and with TrA preactivation (TrA curl-up). Ultrasound images were recorded at 2 points above the umbilicus (U point and UX point). Ultrasound measures of IRD and a novel measure of LA distortion (distortion index: average deviation of the LA from the shortest path between the recti) were compared between 3 tasks (rest, automatic curl-up, TrA curl-up), between groups, and between measurement points (analysis of variance). Results Automatic curl-up by women with DRA narrowed the IRD from resting values (mean U-point between-task difference, -1.19 cm; 95% confidence interval [CI]: -1.45, -0.93; P<.001 and mean UX-point between-task difference, -0.51 cm; 95% CI: -0.69, -0.34; P<.001), but LA distortion increased (mean U-point between-task difference, 0.018; 95% CI: 0.0003, 0.041; P = .046 and mean UX-point between-task difference, 0.025; 95% CI: 0.004, 0.045; P = .02). Although TrA curl-up induced no narrowing or less IRD narrowing than automatic curl-up (mean U-point difference between TrA curl-up versus rest, -0.56 cm; 95% CI: -0.82, -0.31; P<.001 and mean UX-point between-task difference, 0.02 cm; 95% CI: -0.22, 0.19; P = .86), LA distortion was less (mean U-point between-task difference, -0.025; 95% CI: -0.037, -0.012; P<.001 and mean UX-point between-task difference, -0.021; 95% CI: -0.038, -0.005; P = .01). Inter-rectus distance and the distortion index did not change from rest or differ between tasks for controls (P≥.55). Conclusion Narrowing of the IRD during automatic curl-up in DRA distorts the LA. The distortion index requires further validation, but findings imply that less IRD narrowing with TrA preactivation might improve force transfer between sides of the abdomen. The clinical implication is that reduced IRD narrowing by TrA contraction, which has been discouraged, may positively impact abdominal mechanics. J Orthop Sports Phys Ther 2016;46(7):580-589. doi:10.2519/jospt.2016.6536.

Concepts: Standard deviation, Analysis of variance, Absolute deviation, Scientific method, Transversus abdominis muscle, Abdomen, Linea alba, Rectus abdominis muscle

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Currently, autologous breast reconstruction with a free tissue transfer from the lower abdomen is considered to be a safe method that provides a stable long-term solution. The DIEP-flap and the ms-2-TRAM-flap reconstructions have helped reduce donor site morbidity. In order to assess the potential differences between these techniques, we carried out myosonographic evaluations that assessed the muscle dynamics pre- and post-operatively. In addition to investigating the properties of the rectus abdominis muscle post-operatively, this prospective study also allowed us to analyse the muscle preoperatively and to investigate the prospects for harvesting a DIEP-flap as opposed to a TRAM-flap.

Concepts: Plastic surgery, Abdomen, Linea alba, TRAM flap, Rectus abdominis muscle, Human abdomen, Breast reconstruction

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Diastasis recti abdominis is a condition defined as the separation between the rectus abdominis and the linea alba, which leads to weakness in the abdominal muscles. Diastasis may be slight or severe, sometimes resulting in herniation of the abdominal viscera. Following childbirth, most women develop some extent of muscle separation in the postpartum period. However, if the diastasis recti abdominis in the postpartum period remain severe, it should be corrected to prevent concurrent abdominal hernia, strangulation or incarceration. We herein present two Korean cases of postpartum women with severe diastasis recti abdominis with abdominal hernia; it is the first report of its kind from Korea. Two women were referred to our clinic with severe abdominal bulge. Computerized tomography scan showed widening of the linea alba with abdominal hernia. The standard abdominoplasty with multiple wide longitudinal plications of the abdominal wall was performed in each patient under general anesthesia. There was no recurrence of diastasis recti abdominis or abdominal hernia during follow-up periods. The application of abdominoplasty in postpartum women with severe diastasis recti abdominis with abdominal hernia is thus considered to be an efficient management option. We hope these cases can provide a reference for the treatment of similar situations.

Concepts: Postnatal, Human abdomen, Abdominal cavity, Surgery, Linea alba, Rectus abdominis muscle, Abdomen, Childbirth

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Satellite cell (SC) proliferation is observed following erythropoitin treatment in vitro in rodent myoblasts and endurance training in vivo in human skeletal muscle. The present study aimed to investigate the effects of prolonged erythropoiesis-stimulating agent (ESA, darbepoetin-α) treatment and endurance training, separately and combined, on SC quantity and commitment in human skeletal muscle. Thirty-five healthy, untrained men were randomised into four groups: sedentary-placebo (SP, n = 9), sedentary-ESA (SE, n = 9), training-placebo (TP, n = 9), or training-ESA (TE, n = 8). ESA/placebo was injected once weekly and training consisted of ergometer cycling three times/week for 10 weeks. Prior to and following the intervention-period blood samples and muscle biopsies were obtained and maximal oxygen uptake (VO2max ) was measured. Immunohistochemical analyses were used to quantify fibre type specific SCs (Pax7(+) ), myonuclei, and active SCs (Pax7(+) /MyoD(+) ). ESA treatment led to elevated hematocrit while endurance training increased VO2max . Endurance training led to an increase in SCs associated with type II fibres (p<0.05), while type I fibres showed no changes. Both ESA treatment and endurance training increased Pax7(+) /MyoD(+) cells, while only ESA treatment increased the total content of MyoD(+) cells. Epo-R mRNA presence in adult SC was tested with real-time RT-PCR using fluorescence activated cell sorting (CD56(+) /CD45(-) /CD31(-) ) to isolate cells from a human rectus abdominis muscle and found to be considerably higher than in whole muscle. In conclusion, endurance training and ESA treatment may separately stimulate SC commitment to the myogenic program. Furthermore, ESA-treatment may alter SC activity by direct interaction with the Epo-R expressed on SCs. This article is protected by copyright. All rights reserved.

Concepts: Linea alba, Copyright, In vitro, Rectus abdominis muscle, In vivo, Erythropoietin, VO2 max, Skeletal muscle

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Patients with umbilical or epigastric hernias benefit from mesh- based repairs, and even more so if a concomitant rectus diastasis (RD) is present. The ideal technique is, however, still under debate. In this study we introduce the minimal invasive linea alba reconstruction (MILAR) with the supraaponeurotic placement of a fully absorbable synthetic mesh.

Concepts: Hernia, Hernias, Linea alba, Rectus abdominis muscle

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Desmoid-type fibromatosis is characterized by desmoid tumors, which are benign soft tissue tumors that can be locally aggressive but typically do not metastasize. Desmoid tumors can manifest anywhere in the body, and those in the abdominal cavity account for approximately 30 to 50% of all such tumors. Complete resection with free margins has been the standard treatment, but non-surgical therapies have been implemented recently. However, if tumors are strongly invasive and/or persistently recur, radical surgical resection with free margins remains the primary treatment. Unfortunately, radical resection may cause large abdominal defects and hinder reconstruction. Several reports and recommendations have addressed this issue; however, to the best of our knowledge, few reports have described complete resection and the subsequent reconstruction of the rectus abdominis muscle.

Concepts: Linea alba, Resection, Rectus abdominis muscle

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Well-vascularized composite tissue offers improved outcomes for complex head and neck reconstruction. Patients with vessel-depleted necks and failed reconstructions require alternative reconstructive options. We describe a pedicled internal mammary artery osteomyocutaneous chimeric flap (PIMOC) for salvage head and neck reconstruction. Bilateral dissections of 35 fresh cadavers were performed to study individual tissue components and vascular pedicles to develop the PIMOC technique. The flap was then utilized in a series of patients with vessel-depleted neck anatomy. The PIMOC was dissected bilaterally in all cadavers and there were no statistical differences in vascular pedicle caliber or length with regards to laterality or gender. Five patients subsequently underwent this procedure. The flaps included a vertical rectus abdominis myocutaneous component and a 6(th) or 7(th) rib with adjacent muscle and skin to restore bone defects, internal lining, and external coverage. All donor sites were closed primarily. There were no flap losses and all patients gained improvements in facial contour, speech and swallow. Although technically complex, the PIMOC is reproducible and provides a safe and reliable option for salvage head and neck reconstruction. The harvest of the 6(th) or 7(th) rib and rectus abdominis muscle renders an acceptable donor site.

Concepts: Biology, Linea alba, Neck, Rectus abdominis muscle, Anatomy, Dissection, Head and neck anatomy

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The aim of this study is to characterize the passive mechanical behaviour of abdominal wall in vivo in an animal model using only external cameras and numerical analysis. The main objective lies in defining a methodology that provides in vivo information of a specific patient without altering mechanical properties. It is demonstrated in the mechanical study of abdomen for hernia purposes. Mechanical tests consisted on pneumoperitoneum tests performed on New Zealand rabbits, where inner pressure was varied from 0mmHg to 12mmHg. Changes in the external abdominal surface were recorded and several points were tracked. Based on their coordinates we reconstructed a 3D finite element model of the abdominal wall, considering an incompressible hyperelastic material model defined by two parameters. The spatial distributions of these parameters (shear modulus and non linear parameter) were calculated by inverse analysis, using two different types of regularization: Total Variation Diminishing (TVD) and Tikhonov (H(1)). After solving the inverse problem, the distribution of the material parameters were obtained along the abdominal surface. Accuracy of the results was evaluated for the last level of pressure. Results revealed a higher value of the shear modulus in a wide stripe along the craneo-caudal direction, associated with the presence of linea alba in conjunction with fascias and rectus abdominis. Non linear parameter distribution was smoother and the location of higher values varied with the regularization type. Both regularizations proved to yield in an accurate predicted displacement field, but H(1) obtained a smoother material parameter distribution while TVD included some discontinuities. The methodology here presented was able to characterize in vivo the passive non linear mechanical response of the abdominal wall.

Concepts: Linea alba, Regularization, Abdomen, Rectus abdominis muscle, Hyperelastic material, Inverse problem, Materials science, Continuum mechanics

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In advanced pelvic cancer it may be necessary to perform a total pelvic exenteration. In such cases urinary tract reconstruction is usually achieved with the creation of an ileal conduit with a urinary stoma on the right side of the patient’s abdomen and an end colostomy separately on the left. The potential morbidity from a second stoma, may be avoided by the use of a double-barrelled wet colostomy (DBWC), as a single stoma. Another advantage is the possibility to use a vertical rectus abdominis muscle (VRAM) flap for perineal reconstruction.

Concepts: Right-wing politics, Linea alba, Political spectrum, Left-wing politics, Colostomy, Rectus abdominis muscle, French Revolution, Pubic symphysis

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Return to physical activity following childbirth can be a difficult process complicated by structural changes during pregnancy. A common problem is the development of a diastasis of the rectus abdominus (DRA), defined as a horizontal separation of the abdominus muscles at the linea alba. Recent data indicate that the greater the distance of separation of the muscle, the worse the functional ability. We describe a 24-year-old active duty U.S. Navy female G1P2 with a diagnosis of DRA. At 2 months postpartum, she was referred to physical therapy because of back pain and inability to meet baseline activities of daily living. After 4 months of physical therapy, she was unable to complete curl ups as required by U.S. Navy physical fitness standards. Abdominoplasty with imbrication of the abdominal wall diastasis was performed followed by additional physical therapy, after which she returned to baseline functioning. The restoration of functional ability postoperatively suggests there is a therapeutic indication for surgical correction of DRA. In high-functioning military patients with DRA who fail to return to baseline level of activity following a trial of physical therapy, surgical intervention should be considered to obtain the optimal functional ability.

Concepts: Medicine, Childbirth, Physical exercise, Therapy, Muscle, Linea alba, Exercise, Rectus abdominis muscle