Objective To analyze the risk factors of venous thromboembolism(VTE)after endoscopic surgery in elderly patients with urinary system calculi,construct a prediction model and validate it.Methods A retrospective analysis was conducted on the clinical data of 402 elderly patients(≥ 60 years)with urinary system calculi who underwent endoscopic surgery in our hospital during Jan.2018 and Jan.2023.The patients were divided into VTE group(n=43)and non-VTE group(n=359)based on whether VTE occurred after surgery.Risk factors of VTE were screened with univariate and multivariate logistic regression analyses.Based on the screening results(P＜0.05 for the factor),a nomogram prediction model was established,the receiver operating characteristic(ROC)curve was drawn,the area under the curve(AUC)was calculated to determine the efficacy of the model,and a calibration chart was drawn to determine the accuracy of the model.Results Univariate analysis showed that age＞70 years,body mass index(BMI)≥30,VTE history,history of malignant tumors,diabetes,operation time＞180 min,diuretic use during operation,and postoperative ambulation time＞24 h were risk factors of VTE(P＜0.05).Logistic regression analysis showed that age＞70 years,BMI ≥ 30,history of VTE,history of malignant tumors,and operation time＞180 min were independent risk factors of VTE(P＜0.05).The AUC in the ROC curve of the validation set data was 0.789(95％CI:0.731-0.848,P＜0.001).The calibration chart showed that the calibration curve was close to the standard curve(Brier=0.13).Conclusion Age＞70 years,BMI ≥30,history of VTE,history of malignant tumors,and surgery time＞180 min are independent risk factors of postoperative VTE in elderly patients with urinary system calculi undergoing endoscopic surgery.The prediction model can effectively predict the risk factors of postoperative VTE.

Objective To investigate the effects of different foot strike patterns during running on Achilles tendon(AT)morphology and mechanical loading.Methods Fourteen habitual rearfoot strike runners and 14 habitual forefoot strike runners were recruited.Morphological characteristics(tendon length,cross-sectional area,and thickness)of the AT were collected using ultrasound imaging.The AT loading characteristics(plantar flexion moment,tendon force,load rate,impulse,and stress)of subjects wearing cushioned running shoes while running at a speed of 10 km/h were collected and calculated using a three-dimensional force measurement treadmill.Results Compared to habitual rearfoot strike runners,habitual forefoot strike runners showed a significant increase in peak plantar flexion moment of ankle joint,AT peak force,average loading rate,and peak loading rate(P<0.05).However,the differences in AT length,cross-sectional area,and thickness between the two groups were not statistically significant(P>0.05).Conclusions Long-term forefoot strike patterns can adaptively enhance the mechanical loading characteristics of the AT during repetitive stretch-shortening cycles.

Methods: This retrospective analysis included a total of 155 patients who underwent single-level lumbar fusion, with 81 patients in the traditional group and 74 patients in the Wiltse group (less paraspinal muscle damage). QCT was used to measure the volumetric BMD (vBMD), Hounsfield unit value, and cross-sectional area of the paraspinal muscles at the upper instrumented vertebrae (UIV), vertebrae one segment above the UIV (UIV+1), and the vertebrae one segment above the UIV+1 (UIV+2). Statistical analyses were performed. Results: No significant differences in general data were observed between the two groups (p>0.05). Strong correlations were noted between the preoperative and 1-week postoperative vBMD of each segment (p<0.01), with no significant difference between the two time points in both groups (p>0.05). Vertebral BMD loss was significantly higher in UIV+1 and UIV+2 in the traditional group than in the Wiltse group (−13.6%±19.1% vs. −4.2%±16.5%, −10.8%±20.3% vs. −0.9%±37.0%; p<0.05). However, no statistically significant difference was observed in the percent vBMD changes in the UIV segment between the two groups (37.7%±70.1% vs. 36.1%±78.7%, p>0.05). Conclusions QCT can reliably determine BMD in the instrumented spine after lumbar interbody fusion. With QCT, we found that reducing paraspinal muscle destruction through the Wiltse approach during surgery can help preserve the adjacent vertebral BMD; however, it does not help increase the BMD in the instrumented vertebrae.

Objective To investigate the correlation of vertebral bone quality(VBQ)and paraspinal muscle changes with adjacent segment degeneration(ASD)after transforaminal lumbar interbody fusion(TLIF)through a retrospective analysis of patients who have undergone TLIF for lumbar degenerative diseases(LDD).Methods A total of 98 patients who underwent TLIF surgical treatment for LDD between January 2016 and December 2022 at Shenzhen People's Hospital were selected.Well-established follow-up imaging data were available for all subjects who were divided into two groups,the ASD group(n=43)and the non-ASD(N-ASD)group(n=55),according to whether they met the ASD evaluation criteria.Data on the basic characteristics of the patients in both groups were collected,and the relevant parameters,including VBQ and the total cross-sectional area(TCSA)and the functional cross-sectional area(FCSA)of psoas major(PM),erector spinae(ES),and multifidus(MF),were measured by magnetic resonance imaging of the lumbar spine performed preoperatively and at the last follow-up.Then,the relative fat infiltration(RFI)was calculated from the above metrics accordingly.Logistic regression analysis was conducted to investigate the risk factors for ASD.Results The incidence of ASD was 43.9％(n=43)at the final follow-up.The mean follow-up time was(27.23±4.15)months.The age,body mass index(BMI),preoperative bone mineral density(BMD),preoperative VBQ,△RFIPM,and△RFIES+MF showed significant differences between the ASD and N-ASD groups(P＜0.05).According to the results of the logistic regression analysis,BMI(odds ratio[OR]=1.450,95％confidence interval[CI]:1.081-1.945,P=0.013),preoperative VBQ(OR=6.191,95％CI:1.692-22.657,P=0.006),and △RFIES+MF(OR=1.117,95％CI:1.007-1.238,P=0.037)were independent risk factors for ASD.Conclusion The incidence of postoperative ASD in patients who have undergone TLIF for LDD was found to be associated with higher BMI,preoperative VBQ,and increased postoperative relative fat infiltration of the ES and MF muscles.Consequently,it is advisable to prioritize the intraoperative protection of the paraspinal muscles during TLIF.In the postoperative period,it is essential to strengthen exercises of the lower back muscles and to optimize bone mass and weight management,which is conducive to reducing the risk of ASD in the postoperative period.

Sports fatigue of the lower limbs is one of the important factors affecting sports performance. How to improve the anti-fatigue ability of the lower limbs during endurance exercise is the focus of the research field of human sports biomechanics. This study systematically reviewed the relevant literature on transcranial direct current stimulation (tDCS) intervention on lower limb endurance performance, summarized the effect of tDCS on lower limb endurance performance, and analyzed the influencing factors and potential mechanisms. The results showed that: tDCS intervention has a significant effect on the endurance performance of the whole lower limbs, but there is no unified conclusion on the effect on the endurance performance of the knee joint. The researchers deem that tDCS can increase the excitability of the primary motor cortex and reduce the activation of the supplementary motor area and the premotor area to producing a lower rating of perceived exertion, but cannot affect the perception of exercise-induced pain, and stimulation protocols varied across studies, which may be partly responsible. This study can provide a theoretical basis for exploring the central mechanism of tDCS to improve endurance performance, formulating rehabilitation and sports training programsfor different groups of people, and developing new stimulation equipment to enhance the human body’s anti fatigue ability.

Micrognathia is a severe craniofacial deformity affecting appearance and survival. Previous studies revealed that multiple factors involved in the osteogenesis of mandibular bone have contributed to micrognathia, but concerned little on factors other than osteogenesis. In the current study, we found that ectopic activation of Fgf8 by Osr2-cre in the presumptive mesenchyme for masseter tendon in mice led to micrognathia, masseter regression, and the disrupted patterning and differentiation of masseter tendon. Since Myf5-cre;Rosa26R-Fgf8 mice exhibited the normal masseter and mandibular bone, the possibility that the micrognathia and masseter regression resulted directly from the over-expressed Fgf8 was excluded. Further investigation disclosed that a series of chondrogenic markers were ectopically activated in the developing Osr2-cre;Rosa26R-Fgf8 masseter tendon, while the mechanical sensing in the masseter and mandibular bone was obviously reduced. Thus, it suggested that the micrognathia in Osr2-cre;Rosa26R-Fgf8 mice resulted secondarily from the reduced mechanical force transmitted to mandibular bone. Consistently, when tenogenic or myogenic components were deleted from the developing mandibles, both the micrognathia and masseter degeneration took place with the decreased mechanical sensing in mandibular bone, which verified that the loss of mechanical force transmitted by masseter tendon could result in micrognathia. Furthermore, it appeared that the micrognathia resulting from the disrupted tenogenesis was attributed to the impaired osteogenic specification, instead of the differentiation in the periosteal progenitors. Our findings disclose a novel mechanism for mandibular morphogenesis, and shed light on the prevention and treatment for micrognathia.
Mice ; Animals ; Micrognathism ; Masseter Muscle ; Mandible ; Osteogenesis

A patient who suffered soft tissue defects of all 5 digits of left hand was referred to the Department of Hand and Foot Surgery, Affiliated Nanhua Hospital, University of South China in January 2020. A quadruple paddled posterior interosseous artery flaps was used to cover the defect in index, middle, ring and little fingers and a free hallux nail flap was used to repair the defect in thumb. Two years after operation, the appearance and texture of the flaps of all digits in the left hand were good. The function of the digits was good as well. There were slightly noticeable scars left in both the donor sites of left forearm and right foot.

Objective To explore the correlation between foot morphology and toe/metatarsophalangeal joint muscle strength. Methods Twenty-six male recreational runners were recruited. Foot length, truncated foot length, foot width, navicular height, dorsum height at 50% of the foot length, metatarsophalangeal joint strength, tensile force of the first and remaining four toes were measured by using digital caliper, metatarsophalangeal joint strength tester and dynameter, respectively. Partial correlations were used to analyze the correlation between foot morphology and foot muscle strength. ResultsWith adjusted age and body mass index (BMI), the foot width in standing position and truncated foot length in sitting and standing position were positively correlated to tensile force of the first toe; the foot length, foot width and truncated foot length were positively correlated to tensile force of the remaining four toes in both positions, and the arch height index in sitting position was negatively associated with tensile force of the remaining four toes; the foot width was positively correlated to metatarsophalangeal joint strength in both positions. Conclusions The longer foot length, foot width, truncated foot length, and the lower arch height in normal range might be related to the larger foot muscle strength. The consideration of the differences in foot morphological characteristics in different positions during the measurement of foot morphology can provide references for predicting foot muscle strength and preventing foot injury.

Objective To investigate the mechanical properties of Achilles tendon (AT) during running under different shoe conditions (minimalist vs conventional shoes). MethodsSixteen healthy male runners with habitual rearfoot strike patterns were recruited to complete the running trials at the speed of 3.16~3.50 m/s under two shoe conditions. The cross-sectional area of the AT was obtained by ultrasound imaging. Sagittal plane ankle kinematics and ground reaction forces were recorded by motion capture system and three-dimensional force platform simultaneously. Mechanical properties of the ankle and AT were calculated. Paired t test was used to compare the effects of two shoe conditions on various parameters (ankle angle, strike angle, AT force, stress, strain, etc). ResultsCompared with conventional shoes, foot inclination angle was significantly reduced by 39.9% with minimalist shoes. Obvious increase in ankle moment, peak AT force, peak AT loading rate, average loading rate, and obvious decrease in time to peak AT force were observed with minimalist shoes. Peak AT stress, peak AT strain and corresponding stress rate, peak strain rate also increased significantly with minimalist shoes. ConclusionsGreater AT loading was observed when runners with habitual rearfoot strike pattern in conventional shoes begin to wear minimalist shoes. Therefore, a gradual transition to minimalist shoes was recommended for them so as to improve the ability to load adaptively.

Objective:To compare the efficacy of fusion and non-fusion hybrid operation with Dynesys system with the traditional fusion operation with rigid instrumentation in the patients with multi-segment lumbar degenerative disease.Methods:A total of 30 patients with multi-segment lumbar degenerative disease who were subjected to operation from January 2017 to October 2019 in Shenzhen People's Hospital were included in the study. There were 13 males and 17 females, age: 60.8±13.2 years, range: 25 to 83 years. 28 patients with two segments, 1 with three segments, and 1 with four segments. The patients were divided into two groups, i.e the hybrid operation group (13 cases, 9 males and 4 females, average age: 56.6 years, range: 25 to 83 years) versus the traditional fusion group (17 cases, 4 males and 13 females, average age: 63.9 years, range: 46 to 80 years). The main outcome measures were visual analogue scale (VAS), Oswestry disability index (ODI), range of motion (ROM), adjacent segment degeneration (ASD) and complications.Results:There were no statistically significant differences in operation data, such as operation time, intraoperative blood loss, postoperative drainage volume and length of hospitalization, between the two groups. There were no significant differences for ROM in the surgical segments between the two groups before operation (hybrid group and traditional group were 9.6°±4.9° vs. 8.9°±6.1°, t=0.341, P=0.736, respectively). However, after 12 months follow-up, the ROM disappeared in the traditional group and was partially preserved in the hybrid group, with statistically significant differences (hybrid group and traditional group were 5.4°±2.7° vs. 0°, t=9.104, P=0.001, respectively). There was a statistical difference in intervertebral disc height between the two groups at 12 months post-operation, though no statistical difference was found before operation (8.8±1.9 mm vs. 10.5±1.7 mm, t=2.927, P=0.006). There was no statistically significant difference in the intervertebral disc height of the upper adjacent vertebrae between the two groups before and after operation. There were statistically significant differences in ODI scores before operation (63.4%±11.0% vs. 71.3%±9.2%, t=2.146, P=0.041), and 12 months post-operation (17.2%±2.1% vs. 15.5%±2.3%, t=2.091, P=0.046), while no statistical difference was found in VAS scores. Conclusion:The fusion and non-fusion hybrid operation with Dynesys system has comparable clinical efficacy with the traditional fusion operation with rigid instrumentation in the treatment of multisegment lumbar degenerative disease. Meanwhile, the hybrid surgery can preserve the motion of surgical segments and provide a dynamic stability of the vertebral body. The hybrid surgery can be used as a new surgical method for multi-segment lumbar degenerative disease.