The Effect of Rearing Conditions on Carcass Traits, Meat Quality and the Compositions of Fatty Acid and Amino Acid of LTL in Heigai Pigs

The present study evaluates the influence of captivity and grazing rearing conditions on the carcass traits, meat quality and fatty acid profiles of Heigai pigs. Ten Heigai pigs with market weight were randomly selected from both the indoor feeding farm and outdoor grazing farm groups (FF and GF; five pigs per group) for measuring production performance. The results showed that the shear force of longissimus thoracis et lumborum (LTL) in the GF group tended to increase (p = 0.06), and triglyceride and cholesterol contents in LTL and psoas major muscle (PMM) of the GF group significantly increased and decreased, respectively (p < 0.05). The proportion of saturated fatty acids (SFA) was significantly increased (p < 0.05) in the GF group. Meanwhile, the ratios of unsaturated fatty acid (UFA), polyunsaturated fatty acid (PUFA), monounsaturated fatty acid (MUFA) and the content of flavor amino acid of the LTL in the GF group were significantly decreased (p < 0.05). The GF upregulated the expression of MyHC-IIb and lipogenic genes, such as GLUT4 and LPL (p < 0.05), in LTL and PMM, but downregulated the expression of MyHC-I, MyHC-IIa, PPARγ and leptin (p < 0.05). In conclusion, these results suggested that the different rearing conditions can alter the meat qualities by mediating the muscle fiber type and lipid metabolism of Heigai pigs.

Automated major psoas muscle volumetry in computed tomography using machine learning algorithms

Purpose The psoas major muscle (PMM) volume serves as an opportunistic imaging marker in cross-sectional imaging datasets for various clinical applications. Since manual segmentation is time consuming, two different automated segmentation methods, a generative adversarial network architecture (GAN) and a multi-atlas segmentation (MAS), as well as a combined approach of both, were investigated in terms of accuracy of automated volumetrics in given CT datasets. Materials and methods The bilateral PMM was manually segmented by a radiologist in 34 abdominal CT scans, resulting in 68 single 3D muscle segmentations as training data. Three different methods were tested for their ability to generate automated image segmentations: a GAN- and MAS-based approach and a combined approach of both methods (COM). Bilateral PMM volume (PMMV) was calculated in cm3 by each algorithm for every CT. Results were compared to the corresponding ground truth using the Dice similarity coefficient (DSC), Spearman’s correlation coefficient and Wilcoxon signed-rank test. Results Mean PMMV was 239 ± 7.0 cm3 and 308 ± 9.6 cm3, 306 ± 9.5 cm3 and 243 ± 7.3 cm3 for the CNN, MAS and COM, respectively. Compared to the ground truth the CNN and MAS overestimated the PMMV significantly (+ 28.9% and + 28.0%, p < 0.001), while results of the COM were quite accurate (+ 0.7%, p = 0.33). Spearman’s correlation coefficients were 0.38, 0.62 and 0.73, and the DSCs were 0.75 [95%CI: 0.56–0.88], 0.73 [95%CI: 0.54–0.85] and 0.82 [95%CI: 0.65–0.90] for the CNN, MAS and COM, respectively. Conclusion The combined approach was able to efficiently exploit the advantages of both methods (GAN and MAS), resulting in a significantly higher accuracy in PMMV predictions compared to the isolated implementations of both methods. Even with the relatively small set of training data, the segmentation accuracy of this hybrid approach was relatively close to that of the radiologist.

Long-Term Influence of Paraspinal Muscle Quantity in Adolescent Idiopathic Scoliosis Following Deformity Correction by Posterior Approach

Pedicle screw instrumentation (PSI) through posterior approach has been the mainstay of deformity correction for adolescent idiopathic scoliosis (AIS). However, changes in the quantity of paraspinal muscles after AIS surgery has remained largely unknown. The aim of this study was to investigate long-term follow-up changes in paraspinal muscle volume in AIS surgery via a posterior approach. Forty-two AIS patients who underwent deformity correction by posterior approach were analyzed through a longitudinal assessment of a cross-sectional area (CSA) in paraspinal muscles with a minimum five-year follow-up. The CSA were measured using axial computed tomography images at the level of the upper endplate L4 by manual tracing. The last follow-up CSA ratio of the psoas major muscle (124.5%) was significantly increased compared to the preoperative CSA ratio (122.0%) (p < 0.005). The last follow-up CSA ratio of the multifidus and erector spine muscles significantly decreased compared to the preoperative CSA ratio (all p < 0.005). The CSA ratio of the erector spine muscle was correlated with the CSA ratio of the psoas major (correlation coefficient = 0.546, p < 0.001). Therefore, minimizing the injury to the erector spine muscle is imperative to maintaining psoas major muscle development in AIS surgery by posterior approach.

The impact of sarcopenia and myosteatosis in liver transplant candidates on peritransplant course and patient and graft survival

Introduction: Sarcopenia (severe muscle depletion) and myosteaosis (pathological fat accumulation in muscle) are frequent muscle abnormalities in patients with cirrhosis associated with unfavorable prognosis. The aim of our study was to evaluate the impact of sarcopenia and myosteatosis in liver transplant (LT) candidates in our center on the peritransplant course and patient and graft survival. Methods: This prospective study included adult LT candidates who underwent clinical and laboratory examination. The skeletal muscle index (SMI) at L3 level and radiodensity of psoas major muscle (PM-RA) were evaluated by CT. Results: Pretransplant sarcopenia was found in 49 of 103 patients (47.6%) and myosteatosis in 53 (51.5%) patients. Patients with sarcopenia had lower BMI, waist circumference, occurrence of hypertension and metabolic syndrome and lower triglyceride and C-peptide levels than patients without sarcopenia. Patients with myosteatosis had higher Child-Pugh score and lower HDL-cholesterol levels than patients without myosteatosis. Pretransplant SMI negatively correlated with the amount of blood transfusions given during LT and occurrence of biliary complications. Patients with myosteatosis had higher need for blood transfusions during LT and after LT, and higher number of surgical revisions. Occurrence of sarcopenia had no significant effect on patient and graft survival. Patients with myosteatosis had worse long-term survival than patients without myosteatosis, the graft survival did not differ. Conclusion: Sarcopenia and myosteatosis are frequent muscle abnormalities in LT candidates with negative impact on peritransplant course. Myosteatosis was associated with a worse long-term survival in our study. Key words: sarcopenia – myosteatosis – liver transplantation – prevalence – complications – survival

Anatomy of Lumbar Plexus and Implications to Regional Anaesthesiologist

Lumbar plexus is one of the two nerve plexuses which supply the lower limb. It is formed in the posterior abdominal wall within the psoas major muscle. The branches of the plexus exit via the medial and lateral borders as well as its ventral surface. It is a complex plexus which gives a branch to complete the formation of lumbo sacral plexus. The branches mainly supply the groin, anterior and medial compartments of thigh. They also supply the hip and knee joints. The cutaneous innervation by the branches of lumbar plexus is limited to the anterior, lateral and medial parts of the thigh, medial side of the leg and foot and also the lower part of anterior abdominal wall and perineum. Regional anaesthesia is a highly skilled and precise technique used widely in the patients to reduce the drug usage and decrease the intra and post operative complications. Lumbar plexus block can be used in surgeries related to hip joint and anterior part of thigh and groin. To execute the procedure successfully, sound knowledge in anatomy of lumbar plexus is required. Keywords: Lumbar plexus, Branches, Regional anaesthesia.

PSOAS ABSCESS – THE CHANGING TRENDS

Introduction: Psoas abscess (IPA) is an abscess collection in the retroperitoneal space tracking along the psoas major muscle. The microbial etiology of Psoas abscess is variable and depends on the geographical area. This study attempts to evaluate the microbial etiology, its implication in deciding the management modalities, and outcomes in patients with Psoas abscess from a tertiary care center in South India. Materials and Methods: This was a retrospective study done in a tertiary care center in Southern India. Results: A total of 47 patients were enrolled in the study, with causative organism identified in 40 (85.15%) patients. In 17 patients (36.17%), it was found to be tuberculous origin; and of nontuberculous origin in 23 patients (48.93%). No causative organism could not be isolated in 7 patients (14.89%). While 33 patients were treated with percutaneous drainage (70.12%), open drainage was done in 14 patients (29.78%) and 1 patient died (2.12%). Conclusion: The most common causative organism of psoas abscess is found to be of nontuberculous origin and PCD was found to be better modality of treatment. Empirical administration of anti-tuberculous drugs needs further evaluation. Key words: psoas, retroperitoneal, retrospective, tuberculous, drainage, empirical

Relative CT number of periappendiceal fat stranding may be an applicable index for estimating the severity of acute appendicitis

Objectives: To investigate the feasibility of relative CT numbers to periappendiceal fat attenuation as an applicable index for estimating the severity of acute appendicitis. Methods: In total, 308 consecutive surgery-confirmed acute appendicitis patients and 243 controls with available preoperative CT were analyzed retrospectively. The radiological parameters were appendix diameter, length, and wall thickness as concurrent appendicitis signs. CT numbers of periappendiceal fat, mesenteric fat, subcutaneous fat in the anterior and posterior abdominal wall, retroperitoneal fat, gluteal subcutaneous fat and psoas major muscle were measured, as well as the relative CT numbers of periappendiceal fat compared with other locations. Results: There were 287 suppurative acute appendicitis (SAA) and 21 gangrenous or perforated acute appendicitis (GPAA) cases confirmed by pathology. The CT number of periappendiceal fat was significantly higher in patients than in controls (P＜0.01) although there was a wide overlap (−72.33 HU–117.43 HU). Significant differences in relative CT numbers were observed between the groups in gluteal subcutaneous fat (RCTgl) and psoas major muscle (RCTps) (P＜0.01). The AUCs of RCTgl and RCTps showed high accuracy to discriminate acute appendicitis from controls (AUC = 0.803, 0.761; 0.854, 0.847) and GPAA from SAA (AUC = 0.905, 0.851). Conclusions: Attenuation of periappendiceal fat on CT is related to the severity of appendicitis, and relative CT numbers (RCTgl and RCTps) could be an applicable index for severity determination. Advances in knowledge: Periappendiceal fat infiltration is related to the severity of acute appendicitis (especially relative CT number). Other clinical and CT features also need to be considered in the evaluation of inflammation.

Psoas Major Muscle Volume Does Not Affect the Postoperative Thigh Symptoms in XLIF Surgery

Background: Extreme lateral interbody fusion (XLIF) is a minimally invasive surgery that accesses the lumbar spine through the psoas muscle. This study aimed to evaluate the correlation between the psoas major muscle volume and anterior thigh symptoms after XLIF. Methods: Eighty-one patients (mean age 63 years) with degenerative spine diseases underwent XLIF (total = 94 levels). Thirty-eight patients were female (46.9%), and 24 patients (29.6%) had a history of lumbar surgery. Supplemental pedicle screws were used in 48 patients, and lateral plates were used in 28 patients. Neuromonitoring devices were used in all cases. The patients were classified into two groups (presence of thigh symptoms and no thigh symptoms after the surgery). The psoas major volumes were measured and calculated by CT (computed tomography) scan and compared between the two patient groups. Results: In the first 24 h after surgery, 32 patients (39.5%) had thigh symptoms (20 reported pain, 9 reported numbness, and 18 reported weakness). At one year postoperatively, only 3 of 32 patients (9.4%) had persistent symptoms. Conclusions: As a final observation, no statistically significant difference in the mean psoas major volume was found between the group of patients with new postoperative anterior thigh symptoms and those with no thigh symptoms. Preoperative psoas major muscle volume seems not to correlate with postoperative anterior thigh symptoms after XLIF.

Spinal Myxoma of the Facet Joint: A Case Report

Myxoma is a benign soft tissue tumor that can occur in a variety of locations. Intramuscular localization is common, myxomas of the paravertebral muscle are relatively rare and only few cases have been described in literature. Juxta-articular myxoma on facet joint is extraordinary. The current case described paraspinal muscles juxta-articular myxoma of the lumbar region in a 61-year-old man causing back pain and sciatica. Radiological findings showed a mass in the nearby of L5-S1 facet joints mimicking a big synovial cyst that deepened down into the psoas major muscle. A PET scan showed a higher metabolism involving the mass and no other localizations. Intraoperative histological analysis was consistent with Juxta-articular myxoma (JM). Treatment of choice was surgical excision, with complete relief of symptoms afterwards.