Objective To establish a finite element model of rotator cuff which can be used to simulate the rotator cuff injury and to evaluate the biomechanical effects of rotator cuff surgery.Methods The Dicom CT images of the right shoulder of a Chinese healthy volunteer were used to establish models of the scapula,humerus and clavicle.The rotator cuff structures were separated and modeled based on the MRI images and anatomical knowledge.After the rotator cuff model was introduced into the finite element analysis software Abaqus 6.12,the anatomical positions were simulated when the shoulder was at 30° internal rotation,30° external rotation,30° abduction,30° adduction,30° flexion and 30° extension.Results When the shoulder was in 30° flexion,the average stress was 52.2 kPa on the supraspinatus,223.0 kPa on the inffaspinatus and the teres minor,and 90.4 kPa on the subscapularis.When the shoulder was in 30° extension,the average stress was 105.0 kPa on the supraspinatus,78.2 kPa on the infraspinatus and the teres minor,and 55.7 kPa on the subscapularis,indicating that the muscle and tendon of the supraspinatus was subjected to greater stress and the humerus and the scapula produced less stress compared with the shoulder in 30° flexion.Conclusion Since our finite element model of the rotator cuff can simulate common activities of the shoulder joint and obtain stress values of the corresponding rotator cuff muscles,it can be used in simulation of rotator cuff injury and its surgery.

Objective:To evaluate the objective imaging markers of cognitive impairment in patients with end-stage renal disease by MRI intravoxel incoherent motion.Methods:A total of 40 patients with ESRD were enrolled in the Department of Nephrology, Changzhou Second Hospital Affiliated to Nanjing Medical University from January 2019 to August 2020, and 24 healthy controls were prospectively enrolled at the same time.All subjects performed with MRI scan were collected, and the slow apparent diffusion coefficient (ADC slow) of the corresponding brain regions were obtained .The cognitive function was evaluated by the Montreal cognitive assessment scale (MoCA). Two-sample t test was used to analyze the difference of ADC slow and cognitive score between the two groups.Pearson correlation analysis was performed among the cognitive function score of end-stage renal disease and ADC slow value. Results:(1) The score of the intelligence test scale in the ESRD group (23.30±1.76) was significantly lower than that of the healthy control group (27.92±1.00) ( P<0.01). The ADC slow values of bilateral frontal lobe, hippocampus, and insula brain areas (respectively(0.648±0.035), (0.633±0.043), (0.762±0.043), (0.756±0.042), (0.792±0.048), (0.776±0.054))in the ESRD group were significantly higher than those in the healthy control group ((0.600±0.039), 0.610±0.037, (0.725±0.059), (0.711±0.054), (0.740±0.063), (0.716±0.051)) ( P<0.01). (2) Pearson correlation analysis showed that the ADC slow values of bilateral insula and right hippocampus in the ESRD group were negatively correlated with MoCA scales ( r=-0.38, -0.38, -0.66, all P<0.05). Conclusion:ADC slow value in IVIM can better reflect the changes of cognitive function impairment in ESRD patients.

BACKGROUND:Patients with degenerative cervical spondylosis often suffer from changed varicosity of the cervical spine,unbalanced neck-shoulder muscular strength,and descending power. OBJECTIVE:To probe into the correlation between sagittal curvature parameters and pain threshold for neck-shoulder muscles in degenerative cervical spondylosis. METHODS:Totally 50 patients with degenerative cervical spondylosis received treatment at the 3D Printed Outpatient Center of Shanghai Ninth People's Hospital,Shanghai Jiao Tong University School of Medicine from January 2022 to March 2023 were included in the study.After excluding the 10 patients of cervical lateral projection that failed to meet the measurement conditions,the cervical lateral projections were shot to measure the following iconography parameters:Borden value and C2-7 Cobb angle as well as pain thresholds on the midpoint of the superior trapezius muscle in bilateral bundles and at 1 cm beside the C5-6 interspike.The correlation between sagittal curvature parameters and pain threshold of neck-shoulder muscles in degenerative cervical spondylosis was analyzed. RESULTS AND CONCLUSION:(1)The Borden value of sagittal curvature showed a moderately positive correlation with the bundle pain threshold in the left upper trapezius muscle,the bundle pain threshold in the right upper trapezius muscle,and the pain threshold at the 1 cm of the left side beside the C5-6 interspike(r=0.498,P<0.01;r=0.448,P<0.05;r=0.405,P<0.05)and a weak positive correlation with the pain threshold at the 1 cm of the right side beside the C5-6 interspike(r=0.322,P<0.05).(2)The C2-7 Cobb angle showed a weak positive correlation with the left squared myalgia threshold(r=0.355,P<0.05),and there was no correlation with the pain threshold of the left trapezius muscle and the pain threshold at the 1 cm of both sides beside the C5-6 interspike.(3)There was a correlation between the pain threshold of the neck-shoulder muscles,and a high correlation between the pain threshold of the left and right muscles and the pain threshold within the left and right side muscles,indicating that the neck-shoulder muscles are consistent and may be related to the coordination of the neck-shoulder movements.

BACKGROUND:Red light therapy has the non-invasive and cost-effective characteristics,and is widely used in various acute and chronic pains in clinic.However,currently,the phototherapy equipment used in clinic is expensive and has certain site limitations,so it is necessary to explore more convenient and economical phototherapy applications. OBJECTIVE:To observe the clinical efficacy of a self-developed photon cervical vertebra massage instrument for chronic neck pain. METHODS:From November 2022 to February 2023,24 patients with chronic neck pain were recruited from the Department of Rehabilitation Medicine,Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,including 18 females and 6 males,with a mean age of(29.67±6.40)years.The body mass index was(21.39±3.52)kg/m2.Photon cervical vertebra massage instrument was used twice a day for 20 minutes each time for four weeks.The changes in visual analog scale score,pressure pain threshold,neck active activity,neck disability index,and Pittsburgh sleep quality index were observed before,after 2 and 4 weeks of treatment. RESULTS AND CONCLUSION:(1)Compared with before treatment,after four weeks of treatment,visual analog scale score,pressure pain threshold,neck disability index,and Pittsburgh sleep quality index were all improved(P<0.05),while some cervical motion(extension,left and right rotation)improved(P<0.05)after 4 weeks of treatment.(2)Bilateral visual analog scale scores,left trapezius muscle pressure pain threshold,C5C6 pressure pain threshold,and neck disability index improved after 2 weeks of treatment(P<0.05).(3)It is indicated that the application of photon cervical vertebra massage instrument can improve the pain score,muscle tenderness,sleep quality,functional level,and partial active activity of patients with chronic neck pain in a short period,and is a convenient,effective,and safe treatment method.

BACKGROUND:Traditional scoliosis orthosis has some disadvantages,such as complex manufacturing process,long processing cycle,poor fit and so on.Three-dimensional printed scoliosis orthosis has the advantages of high manufacturing precision and personalization. OBJECTIVE:To evaluate the efficacy of three-dimensional printed scoliosis orthosis for scoliosis based on multi-criteria decision model. METHODS:Clinical data of 72 patients with scoliosis admitted to Chen Xinghai Hospital of Integrated Traditional Chinese and Western Medicine from January 2019 to October 2022 were retrospectively collected and divided into two groups according to the treatment of orthosis.Study group(n=23)received three-dimensional printed scoliosis orthosis.Traditional group(n=49)received the traditional polypropylene spine brace treatment.The clinical efficacy and complications were compared between the two groups.A multi-criteria decision model for the treatment of scoliosis with three-dimensional printed scoliosis orthosis was established,and the stability of the benefit value,risk value and decision model of the two groups were evaluated. RESULTS AND CONCLUSION:(1)Compared with the traditional group,there were significant differences in the top vertebral offset distance,Cobb angle,top vertebral rotation,Functional Movement Screen score,visual analog scale score and total effective rate in the study group at 6 months after surgery(P<0.05).(2)Among the benefit indexes,Cobb angle had the greatest impact on the condition of patients,while the risk indexes had the greatest impact on dyspnea.(3)The benefit values of the study group and the traditional group for scoliosis were 79 and 64,and the risk values were 74 and 57,respectively.The combined benefit and risk values found that the benefit-risk value of the study group was 16 higher than that of the traditional group.(4)In the range of 0-100%relative risk weight,the benefit-risk value of the study group was always higher than that of the traditional group,which proved that the multi-criteria decision-making model had good stability.(5)It is indicated that three-dimensional printed scoliosis orthosis can better restore the physiological curvature of scoliosis and improve the efficiency of treatment.

Objective To study topological structure of a new type of three-dimensional (3D) printed height increasing insoles for leg length discrepancy (LLD) and its effect on biomechanics of lower limbs. Methods Topological structure for middle and rear part of the insole was optimized by solid isotropic microstructures with penalization (SIMP), the force was loaded and the boundary conditions were set according to force area of the insole, and the height increasing insole with thermoplastic polyurethanes (TPU) materials was printed by selected laser sintering (SLS). The insoles were used in 9 patients with LLD, visual analogue scale (VAS) and Maryland foot function scores were used to compare pain and foot function changes of patients before and after using the insole, and the 3D gait analysis system was used to compare spatiotemporal parameters and vertical ground reaction force (vGRF) of both lower limbs. Result sAfter the patient wore 3D printed insole, VAS scores decreased, Maryland foot function scores increased, vGRF of both lower limbs decreased, and the difference of cadence, stance phase and swing phase in both lower limbs decreased. Conclusions The 3D printed height increasing insole after topology optimization can improve coordination of lower limb movement, reduce ground impact, relieve pain and improve foot function, thus providing an effective personalized orthopedic plan for LLD treatment in clinic.

Objective: To investigate the feasibility of an accuracy evaluation method for 3D reconstructed bone model based on 3D reconstruction software Arigin3D Pro. Methods: Pig femurs were used as solid models which were scanned by CT and MRI respectively. The scan data were imported into software Arigin3D Pro for 3D model reconstruction by 3 operators with different reconstruction experience (≤1 year, 2 to 3 years, and ≥4 years, respectively). Each operator reconstructed the femurs 3 times and in each reconstruction measured the diameter of the femoral head, the length of the femur and the width of the knee joint at the distal end of the femur 3 times respectively using software Geomagic Wrap. The above parameters of the solid models were measured using a vernier caliper. The parameter values of reconstructed models and solid models were compared and the differences were analyzed. Results: The measurements by Geomagic Wrap showed deviations between the CT and MRI reconstruction models and the solid models, and the maximum deviation percentages were 1.47% and 1.08%, respectively. The percentages of intra-operater difference ranged from 0.29% to 1.53%; the 3D models reconstructed by operators with different reconstruction experience were not identical. Conclusions It is a feasible accuracy evaluation method to compare key parameters between the 3D bone model reconstructed by software Arigin3D Pro and the real animal bone. The deviations of 3D reconstructed bone model based on CT and MRI images are acceptable. The accuracy of 3D bone construction is related to the difference in operators.