Structural remodeling of the lumbar multifidus, thoracolumbar fascia and lateral abdominal wall perimuscular connective tissues: Medium-term test-retest reliability of ultrasound measures.

INTRODUCTION: Growing interest is being paid to the lumbar multifidus (LM) intramuscular fatty infiltrations and fibrosis that are secondary to low back pain as well to the remodeling of perimuscular connective tissues (fasciae) such as the thoracolumbar fascia and fascia sheets separating the abdominal wall muscles. Magnetic resonance imaging and computed tomography have traditionally been used but rehabilitative ultrasound imaging (RUSI) is much more affordable and practical, which can accelerate research and clinical applications on this topic. The aim of this study was to test the medium-term (8 weeks) test-retest reliability of the corresponding RUSI measures. METHODS: Thirty-four participants with non-acute LBP and 30 healthy controls performed a RUSI assessment before and after an 8-week time interval. LM echogenicity was quantified to assess fatty infiltrations and fibrosis while fasciae were quantified with thickness measures. Relative and absolute reliability were estimated using the generalizability theory as a framework, allowing to partition the different sources of error. RESULTS: Overall, the reliability findings were quite acceptable, with negligible systematic effects. Excellent relative reliability was reached in half of the investigated RUSI measures, particularly when averaging measures across trials. However, neither relative, nor absolute reliability results support the use of these RUSI measurements on an individual basis (e.g. clinical applications) but they are useful on a group basis (e.g. research applications). DISCUSSION: The different sources of error were distributed unequally across RUSI measures, pointing to different measurement strategies to mitigate the underlying errors. CONCLUSIONS: The use of the generalizability theory allowed identifying the sources of error of the different RUSI measures. For each category of measure, depending of the distribution of errors, it was possible to recommend specific measurement strategies to mitigate them.

Combined caudal retrocostal and lateral ultrasound-guided approach for transversus abdominis plane injection: A descriptive pilot study in pig cadavers.

Transversus abdominis plane (TAP) block is a regional anesthetic technique used to desensitize the abdominal wall in several species. This study aimed to describe the anatomical characteristics of the abdominal wall and to identify a feasible approach for an US-guided TAP injection that would result in adequate staining of the relevant nerves in the abdominal wall in pig cadavers. Fresh cadavers from five Landrace pigs (age, 12 weeks; body weight, 35.5 ± 1.6 kg) were used. One pig (n = 1) was anatomically dissected, and four pigs (n = 4; i.e., 8 hemiabdomens) were used for TAP injections and evaluation of dye spread. The volume of 0.3 mL/kg/injection point of methylene blue was injected bilaterally. In the caudal retrocostal approach, the injection was performed ventral to the most caudal part of the costal arch. In the lateral approach, the injection was performed between the last rib and iliac crest. A needle was inserted in plane for the caudal retrocostal and the lateral approach caudocranially and craniocaudally, respectively. Successful staining was defined as presence of dye on the nerve for a length of >1 cm in its entire circumference. The TAP was found between different muscle layers in the described anatomical regions. In the caudal retrocostal approach the TAP was found between the external abdominal oblique and transversus abdominis muscle bellies. In the lateral approach the TAP was found between the internal abdominal oblique and transversus abdominis muscles. The approach combining lateral and caudal retrocostal injections at the studied volume stained a median of 5 (3-6) target nerves from the fourth-last thoracic nerve to L2 (six nerves). Combined caudal retrocostal and lateral TAP injections of 0.3 mL/kg/injection point, resulted in staining of target nerve branches which supply the periumbilical and caudal abdominal wall in pig cadavers.

Ultrasound-guided transversus abdominis plane block vs trigger point injections for chronic abdominal wall pain: a randomized clinical trial.

ABSTRACT: The primary aim of this randomized clinical trial is to investigate the effects of ultrasound-guided transversus abdominis plane (TAP) vs ultrasound-guided trigger point injections (TPIs) on numerical rating scale pain scores at month 3 follow-up in patients with a chronic abdominal wall pain. The primary outcome measure was the difference in mean numeric rating scale pain scores between the TAP and TPI groups at month 3 in an intent-to-treat (ITT) analysis. A total of 60 patients were randomized 1:1 to receive an ultrasound-guided TAP block (n = 30) or an ultrasound-guided TPI (n = 30). No significant group differences in baseline demographic or clinical characteristics were observed. The mean baseline pain score for the TAP and TPI groups was 5.5 and 4.7, respectively. In the ITT analysis at month 3, the between-group difference in pain scores was 1.7 (95% confidence interval, 0.3-3.0) favoring the TPI group. In a secondary per-protocol analysis, the between-group difference in pain scores was 1.8 (95% confidence interval, 0.4-3.2) favoring the TPI group. For the ITT and per-protocol analyses, the group differences in pain scores were consistent with a medium effect size. The main finding of this randomized clinical trial is that adults with chronic abdominal wall pain who received a TPI reported significantly lower pain scores at month 3 follow-up compared with patients who received a TAP block.

Changes in the lateral abdominal wall following endoscopic subcutaneous anterior component separation.

PURPOSE: Although changes in lateral abdominal wall musculature after posterior component separation with transversus abdominis release have been investigated, the effects of endoscopic subcutaneous anterior component separation (ES-ACS) on postoperative muscle anatomy have not been evaluated. The purpose of this study was to evaluate changes in the lateral abdominal muscles after ES-ACS. METHODS: Computed tomography (CT) images of patients who underwent ES-ACS were retrospectively evaluated. Lateral abdominal wall thickness and external oblique displacement were measured at the level of fixed retroperitoneal structures. Measurements on the ES-ACS side were compared with those on the contralateral undivided side or with preoperative images in patients with bilateral procedures. RESULTS: Fifteen patients met the criteria for study inclusion. Most patients (n = 13, 86.7%) underwent unilateral ES-ACS. The most commonly performed procedure was laparoscopic intraperitoneal onlay mesh-plus hernia repair (n = 12, 80.0%; the remaining patients underwent open repair). The Mean defect width was 8.4 cm (range 6-15 cm). There was no difference in the thickness of the lateral abdominal musculature between ES-ACS and undivided sides. There was a significant lateral displacement of the external oblique muscle from the lateral edge of the rectus abdominis on the ES-ACS side (mean distance 3.7 cm; p = 0.0006). No midline hernia recurrences, iatrogenic linea semilunaris hernias, or lateral eventrations were observed during a mean follow-up period of 2.6 years (range 0.5-7.4 years). CONCLUSION: ES-ACS resulted in no atrophy of the lateral abdominal muscles in long-term CT follow-up. The procedure is a safe and effective adjunct to complex hernia repair in selected patients.

Structural remodelling of the lumbar multifidus, thoracolumbar fascia and lateral abdominal wall perimuscular connective tissues: A cross-sectional and comparative ultrasound study.

INTRODUCTION: With low back pain (LBP), remodelling of the lumbar soft tissues involves both trunk muscles and neighbouring passive connective tissues. The aim of the present study was to compare three quantitative measures of these tissues, using ultrasound imaging (USI), among healthy controls and individuals with LBP. METHODS: USI measures from 30 healthy subjects and 34 patients with non-acute LBP were compared between groups and sexes. The measures employed were (1) lumbar multifidus echogenicity (fatty/fibrosis infiltration) at three vertebral levels; (2) posterior layer thickness of the thoracolumbar fascia, and (3) thickness of the perimuscular tissues surrounding the external oblique, internal oblique and transversus abdominis (TrA). RESULTS: USI measures of (1) multifidus echogenicity showed statistically significant changes between vertebral levels and sexes (females > males; p = 0.02); (2) differences in thoracolumbar fascia thickness approached statistical significance between groups (LBP > controls; p = 0.09) and sexes (females < males; p = 0.07); and (3) perimuscular tissue surrounding the TrA was significantly thinner (p ≤ 0.001) in patients with LBP compared to controls. DISCUSSION: The thinner perimuscular tissues surrounding the TrA in patients with LBP is a new finding, concurring with previous findings with regard to the lower activation of this deep muscle as well as more recent findings on other perimuscular tissue. CONCLUSION: Overall, USI measures were sensitive to different potential changes (pain status, sex, vertebral level), and this is useful in studying the remodelling of various soft tissues of the trunk.

Bloqueos de tronco / Truncal blocks

Truncal blocks have recently been positioned as an alternative to neuraxial analgesia. The injection of local anesthetics in interfascial planes was initially guided by anatomical landmarks, to later evolve towards a more selective administration when guided by ultrasound. Successful execution of truncal blocks requires detailed knowledge of the chest and abdominal walls anatomy. The same logic allows us to understand its potential benefits concerning perioperative analgesia, as well as its limitations and therapeutic margins. Secondary to a growing interest in less invasive techniques and analgesic techniques with a more favorable risk-benefit profile, the available evidence in this field is in continuous development. Thus, in the present review, the technical aspects of these blocks will be evaluated, emphasizing the sonoanatomy, and assessing the best evidence to support the use of each technique.

Los bloqueos de tronco se han posicionado recientemente como una alternativa frente a la analgesia neuroaxial. La inyección de anestésicos locales en planos interfasciales inicialmente fue guiado por referencias anatómicas, para posteriormente evolucionar hacia una administración más selectiva al ser guiada por el ultrasonido. La ejecución exitosa de los bloqueos de tronco requiere un conocimiento detallado de la anatomía de las paredes del tórax y abdomen. Esta misma lógica nos permite entender sus potenciales beneficios en relación con la analgesia perioperatoria, como también sus limitaciones y margen terapéutico. La evidencia disponible está en continuo desarrollo, dado el creciente interés que concitan técnicas menos invasivas y con un perfil de riesgo-beneficio potencialmente más favorable. En la presente revisión se evaluarán los aspectos técnicos de cada bloqueo, poniendo énfasis en la sonoanatomía, y evaluando la mejor evidencia que sustente el uso de cada técnica.

Abdominal distension after eating lettuce: The role of intestinal gas evaluated in vitro and by abdominal CT imaging.

BACKGROUND: Some patients complain that eating lettuce, gives them gas and abdominal distention. Our aim was to determine to what extent the patients' assertion is sustained by evidence. METHODS: An in vitro study measured the amount of gas produced during the process of fermentation by a preparation of human colonic microbiota (n = 3) of predigested lettuce, as compared to beans, a high gas-releasing substrate, to meat, a low gas-releasing substrate, and to a nutrient-free negative control. A clinical study in patients complaining of abdominal distention after eating lettuce (n = 12) measured the amount of intestinal gas and the morphometric configuration of the abdominal cavity in abdominal CT scans during an episode of lettuce-induced distension as compared to basal conditions. KEY RESULTS: Gas production by microbiota fermentation of lettuce in vitro was similar to that of meat (P = .44), lower than that of beans (by 78 ± 15%; P < .001) and higher than with the nutrient-free control (by 25 ± 19%; P = .05). Patients complaining of abdominal distension after eating lettuce exhibited an increase in girth (35 ± 3 mm larger than basal; P < .001) without significant increase in colonic gas content (39 ± 4 mL increase; P = .071); abdominal distension was related to a descent of the diaphragm (by 7 ± 3 mm; P = .027) with redistribution of normal abdominal contents. CONCLUSION AND INFERENCES: Lettuce is a low gas-releasing substrate for microbiota fermentation and lettuce-induced abdominal distension is produced by an uncoordinated activity of the abdominal walls. Correction of the somatic response might be more effective than the current dietary restriction strategy.

Ultrasound Evaluation of the Abdominal Wall and Lumbar Multifidus Muscles in Participants Who Practice Pilates: A 1-year Follow-up Case Series.

OBJECTIVE: The purpose of this study was to describe ultrasound (US) changes in muscle thickness produced during automatic activation of the transversus abdominis (TrAb), internal oblique (IO), external oblique (EO), and rectus abdominis (RA), as well as the cross-sectional area (CSA) of the lumbar multifidus (LM), after 1 year of Pilates practice. METHODS: A 1-year follow-up case series study with a convenience sample of 17 participants was performed. Indeed, TrAb, IO, EO, and RA thickness, as well as LM CSA changes during automatic tests were measured by US scanning before and after 1 year of Pilates practice twice per week. Furthermore, quality of life changes using the 36-Item Short Form Health Survey and US measurement comparisons of participants who practiced exercises other than Pilates were described. RESULTS: Statistically significant changes were observed for the RA muscle thickness reduction during the active straight leg raise test (P = .007). Participants who practiced other exercises presented a larger LM CSA and IO thickness, which was statistically significant (P < .05). Statistically significant changes were not observed for the domains of the analyzed 36-Item Short Form Health Survey (P > .05). A direct moderate correlation was observed (r = 0.562, P = .019) between the TrAb thickness before and after a 1-year follow-up. CONCLUSIONS: Long-term Pilates practice may reduce the RA thickness automatic activation during active straight leg raise. Furthermore, LM CSA and IO thickness increases were observed in participants who practice other exercise types in conjunction with Pilates. Despite a moderate positive correlation observed for TrAb thickness, the quality of life did not seem to be modified after long-term Pilates practice.

Electromyographic characterisation of abdominal wall trigger points developed after caesarean section and response to local anaesthesia: an observational study.

OBJECTIVE: This study examines the electromyography pattern of abdominal trigger points developed after a caesarean section, and the association between clinical response and local anaesthetic injection. DESIGN: Prospective cohort study. SETTING: A tertiary university hospital. POPULATION: Twenty-nine women with chronic pelvic pain associated with trigger points after a caesarean section were included in the study. METHODS: Participants received needle electromyography before treatment, then underwent a treatment protocol consisting of trigger-point injection of 2 ml of 1% lidocaine. The protocol was repeated once a week for 4 weeks. The clinical responses of the patients were compared 1 week after and 3 months after treatment. The clinical trial is registered with the Brazilian Clinical Trials Registry (REBEC) under RBR-42c6gz (www.ensaiosclinicos.gov.br/rg/RBR-42c6gz/). MAIN OUTCOME MEASURES: Needle electromyography and algometry results and pain reduction. RESULTS: Fifteen patients had abnormal electromyography findings; 14 had normal findings. The rates of response 1 week and 3 months after treatment within the abnormal electromyography group were 95 and 87%, respectively. In the normal group, the rate was 38% both 1 week after and 3 months after treatment. CONCLUSIONS: Trigger points developed after caesarean section, even without clinical symptoms or signs of neuralgia, may originate from neuropathies. Electromyographic abnormalities were associated with pain remission after anaesthesia injection; normal electromyography findings were associated with undiagnosed causes of pain, such as adhesions. TWEETABLE ABSTRACT: Trigger points developed after caesarean section are neuropathies, even in the absence of classical neuralgia.

Recovery after abdominal wall reconstruction.

Incisional hernia is a common long-term complication to abdominal surgery, occurring in more than 20% of all patients. Some of these hernias become giant and affect patients in several ways. This patient group often experiences pain, decreased perceived body image, and loss of physical function, which results in a need for surgical repair of the giant hernia, known as abdominal wall reconstruction. In the current thesis, patients with a giant hernia were examined to achieve a better understanding of their physical and psychological function before and after abdominal wall reconstruction. Study I was a systematic review of the existing standardized methods for assessing quality of life after incisional hernia repair. After a systematic search in the electronic databases Embase and PubMed, a total of 26 studies using standardized measures for assessment of quality of life after incisional hernia repair were found. The most commonly used questionnaire was the generic Short-Form 36, which assesses overall health-related quality of life, addressing both physical and mental health. The second-most common questionnaire was the Carolinas Comfort Scale, which is a disease specific questionnaire addressing pain, movement limitation and mesh sensation in relation to a current or previous hernia. In total, eight different questionnaires were used at varying time points in the 26 studies. In conclusion, standardization of timing and method of quality of life assessment after incisional hernia repair was lacking. Study II was a case-control study of the effects of an enhanced recovery after surgery pathway for patients undergoing abdominal wall reconstruction for a giant hernia. Sixteen consecutive patients were included prospectively after the implementation of a new enhanced recovery after surgery pathway at the Digestive Disease Center, Bispebjerg Hospital, and compared to a control group of 16 patients included retrospectively in the period immediately prior to the implementation of the pathway. The enhanced recovery after surgery pathway included preoperative high-dose steroid, daily assessment of revised discharge criteria and an aggressive approach to restore bowel function (chewing gum and enema on postoperative day two). Patients who followed the enhanced recovery after surgery pathway reported low scores of pain, nausea and fatigue, and were discharged significantly faster than patients in the control group. A non-significant increase in postoperative readmissions and reoperations was observed after the introduction of the enhanced recovery after surgery pathway. Study III and IV were prospective studies of patients undergoing abdominal wall reconstruction for giant incisional hernia, who were compared to a control group of patients with an intact abdominal wall undergoing colorectal resection for benign or low-grade malignant disease. Patients were examined within a week preoperatively and again one year postoperatively. In study III, the respiratory function and respiratory quality of life were assessed, and the results showed that patients with a giant incisional hernia had a decreased expiratory lung function (peak expiratory flow and maximal expiratory pressure) compared to the predicted values and also compared to patients in the control group. Both parameters increased significantly after abdominal wall reconstruction, while no other significant changes were found in objective or subjective measures at one-year follow-up in both groups of patients. Lastly, study IV examined the abdominal wall- and extremity function, as well as overall and disease specific quality of life. We found that patients with a giant hernia had a significantly decreased relative function of the abdominal wall compared to patients with an intact abdominal wall, and that this deficit was offset at one-year follow-up. Patients in the control group showed a postoperative decrease in abdominal wall function, while no changes were found in extremity function in either group. Patients reported improved quality of life after abdominal wall reconstruction. In summary, the studies in this thesis concluded that; standardization of patient-reported outcomes after incisional hernia repair is lacking; enhanced recovery after surgery is feasible: after abdominal wall reconstruction and seems to lower the time to discharge; patients with giant incisional hernia have compromised expiratory lung function and abdominal wall function, both of which are restored one year after abdominal wall reconstruction.

Verification of an optimized stimulation point on the abdominal wall for transcutaneous neuromuscular electrical stimulation for activation of deep lumbar stabilizing muscles.

BACKGROUND CONTEXT: Transcutaneous neuromuscular electrical stimulation (NMES) can stimulate contractions in deep lumbar stabilizing muscles. An optimal protocol has not been devised for the activation of these muscles by NMES, and information is lacking regarding an optimal stimulation point on the abdominal wall. PURPOSE: The goal was to determine a single optimized stimulation point on the abdominal wall for transcutaneous NMES for the activation of deep lumbar stabilizing muscles. STUDY DESIGN: Ultrasound images of the spinal stabilizing muscles were captured during NMES at three sites on the lateral abdominal wall. After an optimal location for the placement of the electrodes was determined, changes in the thickness of the lumbar multifidus (LM) were measured during NMES. METHODS: Three stimulation points were investigated using 20 healthy physically active male volunteers. A reference point R, 1 cm superior to the iliac crest along the midaxillary line, was used. Three study points were used: stimulation point S1 was located 2 cm superior and 2 cm medial to the anterior superior iliac spine, stimulation point S3 was 2 cm below the lowest rib along the same sagittal plane as S1, and stimulation point S2 was midway between S1 and S3. Sessions were conducted stimulating at S1, S2, or S3 using R for reference. Real-time ultrasound imaging (RUSI) of the abdominal muscles was captured during each stimulation session. In addition, RUSI images were captured of the LM during stimulation at S1. RESULTS: Thickness, as measured by RUSI, of the transverse abdominis (TrA), obliquus internus, and obliquus externus was greater during NMES than at rest for all three study points (p<.05). Transverse abdominis was significantly stimulated more by NMES at S1 than at the other points (p<.05). The LM thickness was also significantly greater during NMES at S1 than at rest (p<.05). CONCLUSIONS: Neuromuscular electrical stimulation at S1 optimally activated deep spinal stabilizing muscles, TrA and LM, as evidenced by RUSI. The authors recommend this optimal stimulation point be used for NMES in the course of lumbar spine stabilization training in patients having difficulty initiating contraction of these muscles.

Sonographically guided excisional biopsy of small abdominal wall masses using vacuum-assisted biopsy device.

We report the case of a 37-year-old man who underwent excision of small benign abdominal wall masses using a vacuum-assisted biopsy device designed for breast biopsy (Mammotome). To our knowledge, this is the first application of such a device to remove a soft tissue mass other than a breast lesion.

Electrical muscle stimulation for deep stabilizing muscles in abdominal wall.

Low back pain is associated with dysfunction in recruitment of muscles in the lumbopelvic region. Effective rehabilitation requires preferential activation of deep stabilizing muscle groups. This study was carried out in order to quantify the response of deep stabilizing muscles (transverses abdominis) and superficial muscle in the abdominal wall (external oblique) to electrical muscle stimulation (EMS). Results demonstrate that EMS can preferentially stimulate contractions in the deep stabilizers and may have significant potential as a therapeutic intervention in this area, pending further refinements to the technology.

Endometriosis e la pared abdominal / Endometriosis and the abdominal wall

ANTECEDENTES: La presencia de endometriosis de la pared abdominal (EPA) suele confundirse con otras patologías médico-quirúrgicas que aparecen en la misma zona. OBJETIVO: Evaluar las características clínicas de la EPA. MÉTODO: Se realizó un estudio retrospectivo de todas las pacientes hospitalizadas con el diagnóstico histopatológico de EPA entre enero de 1997 y diciembre de 2005. RESULTADOS: Se encontraron 14 pacientes, con edad promedio de 33,2 años. Los principales síntomas fueron: dolor cíclico (71,4%), masa abdominal (100%), dispareunia (21,4%) y dismenorrea (42,8%). Todas la pacientes tuvieron al menos una cirugía ginecológica (2 con procedimientos laparoscópicos) u obstétrica (85,7% cesárea). Sólo una paciente se había diagnosticado previamente de endometriosis. Los síntomas comenzaron en promedio 3,5 años posteriores a la última cirugía. Las EPA tenían un tamaño promedio de 3,2 cm. El diagnóstico pre-operatorio fue correcto en el 64,3% de las pacientes. Los diagnósticos incorrectos correspondieron a 3 granulomas, una hernia inguinal y un lipoma. Todas las pacientes requirieron cirugía y en el 64,3% fue necesario la utilización de mallas polytetrafluoethyleno. Cuatro pacientes (28,5%) presentaron recurrencias. 60% de los diagnósticos iniciales incorrectos v/s 11,1% de los acertados recurrieron. CONCLUSIONES: La EPA puede encontrarse en cicatrices tanto ginecológicas como obstétricas. Los síntomas comunes son masas con dolor cíclico. La ecografía de pared abdominal fue suficiente para enfrentar el diagnóstico diferencial. El diagnóstico pre-operatorio es importante para planificar la cirugía porque redujo las recurrencias. El tratamiento de elección es la cirugía con resección amplia de los bordes.

BACKGROUND: The presence of abdominal wall endometriosis (AWE) used to be confused with other surgical pathologies that may appear in these zones. Objective: To evaluate the AWE clinical characteristics. METHOD: Retrospective study of all the patients hospitalized with the histopathologycal diagnosis of AWE, between January 1997 and December 2005. RESULTS: There was found AWE only in 14 patients. Their mean age was 33.2 years old. The symptoms were: cyclic pain (71.4%), abdominal wall mass (100%), dyspareunia (21.4%) and dysmenorrhea (42.8%). All patients had at least one gynecologic (2 patients with laparoscopic procedures) or obstetric surgery (85.7% had previous cesarean section). Only one patient had previously been diagnosed with pelvic endometriosis. Their symptoms started after an average of 3.5 years after surgery. The AWE had a mean size of 3.2 cm. The preoperative diagnosis was correct in 64.3%. The incorrect preoperative diagnoses were 3 granuloma, 1 inguinal hernia and 1 lipoma. All patients required surgery. 64.3% of the patients it was necessary a polytetrafluoethylene mesh. Four patients (28.5%) had AWE recurrences. 60% of the wrong initial diagnosis recurred versus 11.1% of the correct ones. CONCLUSION: AWE may be present in gynecologic or obstetric scars. Their common symptoms are masses with cyclic pain. Ultrasonography is enough to approach the differential diagnosis. The correct preoperative diagnosis is important to plan surgery and reduce recurrences. The surgical wide excision is the preferable treatment. Establishing clear endometriosis limits reduce the recurrences.