Objective: To measure the cross-sectional area (CSA) and fatty infiltration (FI) of lumbar paravertebral muscles in patients with degenerative lumbar scoliosis (DLS), and to analyze the mechanism and clinical significance of paravertebral muscles degeneration. Methods: A retrospective study was performed on 118 patients with DLS who were enrolled in our hospital from September 2016 to September 2017. All patients had complete preoperative image data. Preoperative lumbar lordosis (LL), Cobb angle, and vertebral rotation were measured on spinal X-ray plain film. The CSA and FI of the paravertebral muscle on the upper and lower intervertebral level of the scoliosis apical vertebrae were measured by lumbar MRI, and the CSA, FI and their correlation with the Cobb angle were compared. Results: This study enrolled 118 DLS patients, including 49 males and 69 females. The mean age of the patients was 65.4 ± 7.2 years, with an average BMI of 24.7 ± 3.4 and lumbar symptoms including LBP, sciatica, numbness and intermittent claudication, decreased myodynamia and other symptoms. The lasting time of symptoms were 21 months (3-60 months). The Cobb angle of the patients averaged 18.5°±6.7°. Of all patients, 60 patients had a scoliosis to the left, and 58 patients had a scoliosis to the right. The number of patients with lateral apical vertebrae located at L1-L4 were: 12 cases of L1, 41 cases of L2, 49 cases of L3, 16 cases of L4. The CSA of the concave side psoas muscle was significantly larger than that of the convex side(upper intervertebral level, concave side 3.74±2.17 cm², convex side 3.56±1.91 cm²; lower intervertebral level, concave side 6.54±3.08 cm², convex side 6.31±3.302 cm². And the CSA of the concave side multifidus muscle and the extensor muscle group was significantly smaller than the convex side, multifidus muscle: upper intervertebral level, concave side 9.47±3.86 cm², convex side 10.25±4.20 cm²; lower intervertebral level, concave side 9.30±3.61 cm², convex side 10.21±3.81 cm²; extensor muscle group: upper intervertebral level, concave side 18.35±4.94 cm², convex side 19.37±5.17 cm²; lower intervertebral level, concave side 18.98±4.73 cm², convex side 19.81±5.16 cm². The concave side FI of extensor muscle group is significantly larger than the convex side, upper intervertebral level, concave side 30.63±15.09, convex side 23.48±15.00; lower intervertebral level, concave side 37.87±19.38, convex side 30.43±16.89. There was a correlation between the degree of asymmetry of CSA and FI in the multifidus, dorsal extension muscles, paravertebral muscle and the scoliosis Cobb angle. Conclusion The paravertebral muscles of lumbar vertebrae are not a whole in the degenerative changes of DLS. There are different anatomical and physiological effects of lumbar flexion and extension muscle groups. The extensor muscles play an important role in antagonizing the progression of DLS. Improving paravertebral muscle function is an important element in the treatment of DLS.

Objective: To evaluate the influence of PI-LL (pelvic incidence minus lumbar lordosis mismatch) on scoliosis correction, living quality and internal fixation related complications for adult degenerative scoliosis (ASD) after long posterior instrumentation and fusion. Methods: A total of 79 patients with ADS underwent long posterior instrumentation and fusion in the Department of Orthopedics at Beijing Chao Yang Hospital from January 2010 to January 2014 were retrospectively reviewed.There were 21 males and 58 females aging from 55 to 72 years with the mean age (63.4±4.8)years. The patients were divided into three groups according to immediately postoperative PI-LL: PI-LL<10°, 10°≤PI-LL≤20°, PI-LL>20°.Compare the Cobb′s angles, PI-LL, Japanese Orthopaedic Association (JOA) score, Oswestry Disability Index (ODI), Visual Analog Scale (VAS) and Lumbar Stiffness Disability Index (LSDI). Measurement data were compared via t test and ANOVA, enumeration data were compared via Kruskal-Wallis test, noncontiguous data was performed by χ² test. Univariate linear regression equation was performed to investigate the relative influences of postoperative PI-LL on postoperative radiographic parameters and clinical outcome. Results: All the operations were successful without intraoperative complications. The operation time was 145-310 minutes (235.3±42.0) minutes, the intraoperative blood loss was 300-5 300 ml (1 021±787) ml, the duration of hospital was 12-18 d (14.5±1.3) d. A total of 4 to 10 (7.0±1.1) vertebra levels were fused. Compared to preoperative, the Cobb′s angle of scoliosis ((4.2±1.8)° vs. (20.1±2.7)°), PI-LL ((16.1±8.6)° vs. (36.0±4.3)°), JOA (3.0±1.3 vs. 5.5±1.2), ODI (24.4±8.1 vs. 62.9±2.7), VAS (3.0±1.0 vs. 6.8±1.3) were significantly decreased postoperative (t=18.539~53.826, P<0.01). Compared to preoperative, postoperative Cobb′s angle of scoliosis ((4.1±2.7)° vs. (19.5±2.7)°, (4.0±1.4)° vs. (20.2±2.4)°, (4.7±0.9)° vs. (20.6±3.0)°) (t=21.148-45.355, P<0.01) and PI-LL ((5.2±2.8)° vs. (35.8±4.9)°, (17.9±2.9)° vs. (37.2±3.9)°, (25.8±2.7)° vs. (34.5±4.0)°) (t=7.227-38.250, P<0.01) were significantly reduced postoperative in PI-LL<10° group, 10°≤PI-LL≤20° group and PI-LL>20° group. Compared to preoperative, ODI (27.7±4.9 vs. 63.3±2.6, 17.7±5.9 vs. 63.1±2.8, 30.6±6.5 vs. 62.3±2.5) (t=21.218~50.858, P<0.01), JOA (2.8±1.2 vs. 5.2±1.2, 3.3±1.1 vs. 5.7±1.1, 2.8±1.7 vs. 5.7±1.2) (t=9.042-16.025, P<0.01) and VAS (2.9±1.2 vs.7.0±1.3, 3.3±0.9 vs.7.0±1.4, 2.9±0.8 vs. 6.3±1.2) (t=16.073-22.214, P<0.01) were all significantly reduced at last follow-up. There were statistic differences in ODI and LSDI (F=38.477, P<0.01; F=37.063, P<0.01) at the last follow-up among the three groups. There was a negative correlation in PI-LL and LSDI according to linear regression (B=-5.838, P<0.01) in the last follow-up. All the patients were followed up, the follow-up duration were 2 to 5 years with the mean (3.1±0.7) years. The internal fixation failure related complications in 3 years included proximal junctional kyphosis (PJK) in 19 cases, internal fixation loosening in 6 cases. Eight patients received reoperation for severe local pain and low extremity symptoms. PJK occurrences were significantly different among PI-LL<10° group, 10°≤PI-LL≤20° group and PI-LL>20° group. Conclusions The PI-LL between 10° and 20° may be the best choice in ADS patients after long posterior instrumentation and fusion for its better clinical outcome and less proximal junctional kyphosis (PJK). The overcorrection of LL may lead to more serious postoperative lumbar stiffness.

Objective:To analyze the differences in clinical and endoscopic ultrasonography (EUS) findings between diffuse and focal IgG4-related autoimmune pancreatitis (IgG4-AIP).Methods:Data of patients diagnosed as having IgG4-AIP who underwent EUS at Chinese PLA General Hospital from September 2011 to April 2022 were retrospectively collected. General clinical data, EUS features, and postoperative pathology were analyzed for characteristic differences.Results:A total of 40 patients were included in the study, 60.03±10.87 years old, a higher proportion of males (85.0%, 34/40). All patients underwent EUS, and 28 underwent EUS-guided fine-needle aspiration. Among the 40 patients, 29 (72.5%) had diffuse type and 11 (27.5%) had focal type. Abdominal pain [65.5% (19/29) VS 18.2% (2/11), χ2=5.393, P=0.020] and thickening of the bile duct wall [51.7% (15/29) VS 9.1% (1/11), χ2=4.394, P=0.036] were more common in the diffuse type, while main pancreatic duct dilation [45.5% (5/11) VS 10.3% (3/29), χ2=4.146, P=0.042] was more common in the focal type, with the lesion most commonly located in the pancreatic head (90.9%, 10/11). There was no significant difference in the presence of chronic pancreatitis parenchymal changes between the two groups [34.5% (10/29) VS 27.3% (3/11), χ2=0.003, P=0.955]. Conclusion:There are certain differences in abdominal pain and biliary and pancreatic duct lesions between diffuse and focal AIP. The high expression of chronic pancreatitis characteristics is not observed in either group, which provides clues for the classification of AIP in clinical practice.