Numerical Modeling of Human Middle Ear Biomechanics Using Finite Element Method

An accurate finite element （ FE ） model of the human middle ear can provide better understanding of the mechanics of middle ear, and can be used for aiding the design of the implantable middle ear hearing devices. In this paper, a threedimensional （3D） FE model of the human middle ear was constructed, including the tympanic membrane, ossicular bones, and middle ear suspensory ligaments/museles. This model was constructed based on a complete set of computerized tomography section images of a healthy volunteer＇s left ear by reverse engineering technology. The validity of this model was confirmed by comparing the motions of the tympanic membrane and stapes footplate obtained by this model with published experimental measurements on human temporal bones. The result shows that the model is reasonable in predicting the biomechanics of the human middle ear.

Impact of parenchyma-preserving surgical methods on treating patients with solid pseudopapillary neoplasms:A retrospective study with a large sample size

BACKGROUND Solid pseudopapillary neoplasm of the pancreas(SPN)is a rare neoplasm that mainly affects young women.AIM To evaluate the impact of parenchyma-preserving surgical methods(PPMs,including enucleation and central pancreatectomy)in the treatment of SPN patients.METHODS From 2013 to 2019,patients who underwent pancreatectomy for SPNs were retrospectively reviewed.The baseline characteristics,intraoperative index,pathological outcomes,short-term complications and long-term follow-up data were compared between the PPM group and the conventional method(CM)group.RESULTS In total,166 patients were included in this study.Of them,33 patients(19.9%)underwent PPM.Most of the tumors(104/166,62.7%)were found accidentally.Comparing the parameters between groups,the hospital stay d(12.35 vs 13.5 d,P=0.49),total expense(44213 vs 54084 yuan,P=0.21),operation duration(135 vs 120 min,P=0.71),and intraoperative bleeding volume(200 vs 100 mL,P=0.49)did not differ between groups.Regarding pathological outcomes,tumor size(45 vs 32 mm,P=0.07),Ki67 index(P=0.53),peripheral tissue invasion(11.3%vs 9.1%,P=0.43)and positive margin status(7.5%vs 6%,P=0.28)also did not differ between groups.Moreover,PPM did not increase the risk of severe postoperative pancreatic fistula(3.8%vs 3.0%,P=0.85)or tumor recurrence(3.0%vs 6.0%,P=0.39).However,the number of patients who had exocrine insufficiency during follow-up was significantly lower in the PPM group(21.8%vs 3%,P=0.024).CM was identified as an independent risk factor for pancreatic exocrine insufficiency(odds ratio=8.195,95%confident interval:1.067-62.93).CONCLUSION PPM for SPN appears to be feasible and safe for preserving the exocrine function of the pancreas.

Observation of Curative Effect of Surgical Nursing in Patients with Grade III Hand-Foot Syndrome

Objective: To investigate the effect of surgical nursing on grade III Hand-Foot Syndrome (HFS) induced by Doxorubicin hydrochloride liposome chemotherapy after breast cancer surgery. Method: From January 2019 to December 2019, 10 patients with HFS grade III caused by Doxorubicin hydrochloride liposome chemotherapy after breast cancer surgery in the Breast Department of Cancer Prevention and Treatment Center of Sun Yat-sen University were selected, and surgical nursing methods were used to intervene and observe the therapeutic effects of the patients. Results: One patient was cured within 7 days, the cure rate was 10% in 7 days, 8 patients were cured within 10 days, the cure rate was 80% in 10 days, 10 patients were cured within 15 days, the cure rate was 100% in 15 days. Conclusion: The surgical nursing method is effective for patients with grade III HFS caused by Doxorubicin hydrochloride liposome chemotherapy after breast cancer surgery, shortening the treatment time of HFS, and is worthy of clinical promotion.

Modified surgical method of supra-and infratentorial epidural hematoma and the related anatomical study of the squamous part of the occipital bone

BACKGROUND Supra-and infratentorial acute epidural hematoma(SIEDH)is a common posterior cranial fossa epidural hematoma located at the inner surface of the squamous part of the occipital bone(SOB).Traditionally,surgical treatment of the SIEDH requires a combined supra-infratentorial craniotomy.AIM To analyze the morphological characteristics of the SOB and introduce a single supratentorial craniotomy for SIEDH.METHODS Skull computed tomography(CT)scan data from 32 adult patients were collected from January 1,2019 to January 31,2020.On the median sagittal plane of the CT scan,the angle of the SOB(ASOB)was defined by two lines:Line A was defined from the lambdoid suture(LambS)to the external occipital protuberance(EOP),while line B was defined from the EOP to the posterior edge of the foramen magnum(poFM).The operative angle for the SIEDH(OAS)from the supra-to infratentorial epidural space was determined by two lines:The first line passes from the midpoint between the EOP and the LambS to the poFM,while the second line passes from the EOP to the poFM.The ASOB and OAS were measured and analyzed.RESULTS Based on the anatomical study,a single supratentorial craniotomy was performed in 8 patients with SIEDH.The procedure and the results of the modified surgical method were demonstrated in detail.For males,the ASOB was 118.4±4.7 and the OAS was 15.1±1.8;for females,the ASOB was 130.4±5.1 and the OAS was 12.8±2.0.There were significant differences between males and females both in ASOB and OAS.The smaller the ASOB was,the larger the OAS was.The bone flaps in 8 patients were designed above the transverse sinus intraoperatively,and the SIEDH was completely removed without suboccipital craniotomy.The SOB does not present as a single straight plane but bends at an angle around the EOP and the superior nuchal lines.The OAS was negatively correlated with the ASOB.CONCLUSION The single supratentorial craniotomy for SIEDH is reliable and effective.

New Method of Reconstruction from Nonparallel Stereo and Application to Surgical Navigator

A new method to reconstruct 3D scene points from nonparallel stereo is proposed. From a pair of conjugate images in an arbitrarily configured stereo system that has been calibrated, coordinates of 3D scene points can be computed directly using the method, bypassing the process of rectifying images or iterative solution involved in existing methods. Experiment results from both simulated data and real images validate the method. Practical application to surgical navigator shows that the method has advantages to improve efficiency and accuracy of 3D reconstruction from nonparallel stereo system in comparison with the conventional method that employs algorithm for standard parallel axes stereo geometry.

Embryo Transfer by Surgical Method with Landrace as Receptor Sow

[ Objective] The paper was to test the feasibility of embryo transfer technique in pig production. [ Method ] Twenty-four estrus muhiparity Landraee sows provided by Longjing Agricultural Science and Technology Institute were performed embryo transfer surgery, and postoperative effects were observed. [ Result] Totally 11 out of 24 receptor sows were pregnant ; pregnant sows delivered 67 cloned piglets, and the average farrowing rate of sows was approximately 6 piglets/sow. There were 22 mortalities of newborn piglets because of various reasons. [ Conclusion] Embryo transfer technique is an indispensable link in pig production, and an important means of pig breeding and improvement.

Surgical organ displacement: what is the best “materials and methods” for proton radiotherapy?

In the mid 1940s, Robert Wilson （1） hypothesized that a highly localized deposition of energy from a proton beam could be used to increase the radiation dose to tumors while minimizing radiation to adjacent normal tissues. The depth- dose distribution of a proton beam differs significantly from that of a photon beam. Protons show increasing energy deposition with penetration distance, reaching a maximum- named the Bragg peak-near the end of the range of the proton beam. In front of the Bragg peak, the dose level is modest compared to photon beams; beyond the Bragg peak, the dose decreases to nearly zero. By choosing the appropriate proton beam energy, the depth of the Bragg peak can be adjusted to match the depth and extent of the target volume. Therefore, excellent conformality can be achieved, in contrast to conventional or intensity-modulated radiotherapy （IMRT）.

Application Effect of Informationized Teaching Method Based on Evidence-based Nursing in Surgical Nursing Teaching

Objective:The study was to analyze the application effect of informationized teaching method based on evidence-based nursing in surgical nursing teaching.Methods:From December 2019 to December 2020,60 students were selected as the research objects and randomly divided into two groups,each with 30 students in the teaching group.The observation group applied informationized teaching based on evidence-based nursing method,and the control group used the traditional teaching model.The teaching effect was evaluated.Results:The test scores of subjective theoretical knowledge and objective theoretical knowledge of the observation group were significantly higher than those of the control group,and the comprehensive ability evaluation of the observation group was also higher(P<0.05).The majority of students accepted the informationized teaching method based on evidence-based nursing,and a few held a neutral or disapproval attitude.Conclusion:Informationized teaching method based on evidencebased nursing can improve students'theoretical and practical levels in surgical nursing teaching,and most students also accept this teaching method,which has application value.

Selection of surgical methods for thoracic ossification of ligamentum flavum combined with cervical spondylotic myelopathy

Objective To investigate the difference between different surgical methods for thoracic ossification of ligamentum flavum(OLF) combined with cervical spondylotic myelopathy(CSM) . Methods From January 1991 to January 2003,56 cases

Microsurgical efficacy in 326 children with tethered cord syndrome: a retrospective analysis

Tethered cord syndrome is a progressive disease with a typically insidious onset in infants and children, and which can lead to persistent progress of neurological deficits and a high rate of disability without timely intervention. The purpose of this study was to investigate the curative effect of microsurgery in children with different types of tethered cord syndrome. In this study, we analyzed 326 patients with tethered cord syndrome, aged from 2 months to 14 years old, who were followed for 3-36 months after microscopic surgery. Based on clinical manifestations and imaging findings, these patients were classified into five types： tight ilium terminale （53 cases）, lipomyelome- ningocele （55 cases）, lipomatous malformation （124 cases）, postoperative adhesions （56 cases）, and split cord malformation （38 cases）. All patients underwent microsurgery. Curative effects were measured before and 3 months after surgery by Spina Bifida Neurological Scale based on sensory and motor functions, reflexes, and bladder and bowel function. The results showed that Spina Bifida Neurological Scale scores improved in all five types after surgery. Overall effective rates in these patients were 75%. Effective rates were 91% in tight ilium terminale, 84% in lipomyelomeningocele, 65% in lipomatous malformation, 75% in postoperative adhesion, and 79% in split cord mal- formation. Binary logistic regression analysis revealed that types of tethered cord syndrome （lipoma-type or not） and symptom duration before surgery were independent influencing factors of surgical outcome. These results show that therapeutic effect is markedly different in patients with different types of tethered cord syndrome. Suitable clinical classification for tethered cord syndrome will be helpful in predicting prognosis and guiding treatment. This trial has been registered in the Chinese Clinical Trial Registry （registration number： ChiCTR1800016464）.

Reconstruction of the Medial Patellofemoral Ligament Using Hamstring Tendon Graft With Different Methods:a Biomechanical Study

Objective To measure the tensile strength of the normal medial patellofemoral ligament(MPFL),and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the patella.Methods Eight fresh cadaver knees were prepared by isolating the patella,leaving only the MPFL as its attachment to the medial condyle of femur.The MPFL was reconstructed by three different methods:four-suture fixation,anchors-single suture fixation,and anchors-double suture fixation.The tensile strength and the elongation of the normal MPFL and the tendon grafts were measured.Results The tensile strength of the four-suture fixation group(234.86±49.02 N)was stronger than that of the normal MPFL(146.91±25.30 N,P=0.0014)and the anchors-single suture group(159.17±49.07N,P=0.0077),while weaker than that of the anchors-double suture group(314.74±78.46 N,P=0.0052)Conclusions With regard to the tensile strength,the four-suture fixation method is reliable for clinical use.Compared with the anchor-suture method,the four-suture fixation method which has no specific implants is more economical,convenient and efficient.

SURGICAL TREATMENT OF METASTATIC SPINAL TUMOR

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SURGICAL MANAGEMENT OF EHLERS-DANLOS SYNDROME:FIRST REPORT OF A PEDIGREE IN CHINA

OBJECTIVE: To describe a case of Ehlers-Danlos syndrome type IV and its pedigree in China. METHODS: Clinical materials of a case of Ehlers-Danlos syndrome type IV and a pedigree of 6 members within 4 generations were analyzed. Dilated internal jugular vein in the proband was removed by operation. The diagnosis, surgical treatment, and postoperative complications were retrospectively reviewed. RESULTS: Vessels of the proband in the pedigree were crisp and easily lacinated during the procedure of removing his internal jugular vein. Repeating postoperative hematomas were found though complete stanching was achieved during the operation. The patient was successfully recovered by promptly debridgement and needle sucking. The other 5 members of the pedigree all had the triads of Ehlers-Danlos syndrome. CONCLUSIONS: Though it was of extremely low morbidity rate, the high mortality rate and complication of Ehlers-Danlos syndrome deserve great attention during surgical management, especially in patients with Ehlers-Danlos syndrome type IV. Surgeons should be aware of the ponderance of its complications and combined diseases to avoid fatal intraoperative vascular lascination and incontrollable hemorrhage.

A Two-Dimensional Mathematical Model to Analyze Thermal Variations in Skin and Subcutaneous Tissue Region of Human Limb during Surgical Wound Healing

During wound healing, the metabolic activity associated with each phase must occur in the proper sequence, at a specific time, and continue for a specific duration at an optimal intensity. Any disturbance in appropriate thermal environment may complicate the wound healing process and may give rise to wound infection. In the presented paper a transient state two-dimensional mathematical model has been developed to analyse thermal variations in skin and subcutaneous tissue (SST) region of human limb. Due to circular shape of human limb, model has been developed in polar coordinates. The domain of the study consists of two types of tissues: abnormal tissues and normal tissues. The post surgery peripheral tissue of human limb during healing time is considered as abnormal tissues. The effect of variable density of blood vessels in dermal layer of both tissues on the physical and physiological parameters is incorporated in the model. The effect of healing on physiological parameters of abnormal tissue is incorporated by considering the physiological parameters to be function of time “t”. The effect of different climatic conditions is considered in the model. Taking into account the variable core temperature due to anatomy of arteries and variable physiological parameters in dermal layer of peripheral region, the well known Pennes’ bio heat equation is used to analyse the time-dependent temperature distribution of both normal and abnormal tissues. Comparison between temperature profiles of both normal and abnormal tissue has been done using finite element approach with bilinear shape functions in polar coordinates. A computer program in MATLAB has been developed to simulate the results.

DIAGNOSIS AND SURGICAL MANAGEMENT FOR RETROSTERNAL THYROID MASS

<Abstract

Effect of cervical spine surgery on the biomechanics of the cervical spine

In clinical practice,cervical spine surgery inevitably alters the original physiological structure of the cervical spine,thus causing changes in the original biomechanical properties of the cervical spine.The biomechanical properties of the cervical spine are particularly significant as it is an essential structure that supports the head and connects the trunk.Different cervical spine surgery options can have different effects on the biomechanics of the cervical spine.Therefore,this review will discuss recent research advances on the effects of cervical spine surgery on cervical spine biomechanics.We hope that this review will provide some theoretical basis for future studies on the biomechanical effects of cervical spine surgery on the cervical spine.

A new abdominal drainage tube fixation method for 3-port laparoscopic cholecystectomy improves patients’postoperative quality of life

Objective Laparoscopic surgery has become a routine general surgery with many advantages,such as alleviating abdominal pain.However,postoperative pain caused by abdominal drainage tubes has attracted little attention from medical staff.The aim of this study was to explore the influence of a new abdominal drainage tube fixation method for 3-port laparoscopic cholecystectomy(LC)on patients’postoperative quality of life.Methods Patients who underwent 3-port LC with abdominal drainage tubes in the Department of Hepatobiliary Surgery of Linyi People’s Hospital from March 1,2023 to October 31,2023 due to gallstones with chronic cholecystitis were selected for this study.The patients were randomly divided into an experimental group and a control group.In the experimental group,the new abdominal drainage tube fixation method was used,while in the control group,the traditional method was used.Afterward,the quality of life of patient in terms of pain,activity,recovery time,and mental health status was evaluated.The exudate around the patient’s drainage tube was collected for bacterial culture and analysis.Results A total of 139 patients were randomly divided into an experimental group(70 patients)and a control group(69 patients).The patients’baseline characteristics were not significantly different.The patients in the experimental group had better outcomes in quality of life,with higher pain scores(24.03±2.37 vs.15.48±2.29,p<0.001)and activity scores(20.57±1.78 vs.14.13±1.43,p<0.001),and a shorter postoperative recovery time(2.36±0.68 d vs.2.96±1.34 d,p<0.001).The same results were shown in linear regression analysis scores of the 2 groups.The positive rate of bacterial culture in the exudate around the patient’s drainage tube in the experimental group was significantly lower than that in the control group(12.9%vs.43.5%,p<0.001);and furthermore,the positive rate of conditional pathogenic bacteria was even lower(7.1%vs.33.3%,p<0.001)in the experimental group than in the control group.Conclusion This new abdominal drainage tube fixation method can effectively promote patient rehabilitation and improve the quality of life for patient following 3-port LC with abdominal drainage tubes.

有限元法在脊柱胸腰段骨折生物力学分析中的应用及发展方向

背景:脊柱骨折最高发部位是胸腰段,其症状为后背部疼痛、后凸畸形、活动受限,或伴脊髓神经损伤引发下肢疼痛、麻木甚至截瘫等并发症。有限元法是一种数字化的计算机建模技术,能真实模拟实物模型并进行受力分析。目的:综述有限元法在脊柱胸腰段骨折中的应用。方法:在中英文文献数据库PubMed、Web of Science、中国知网中检索2024年3月之前发表的有限元分析法在脊柱胸腰段骨折中应用的相关文献,中英文检索词为“有限元分析法(finite element analysis methods)”“生物力学(biomechanical phenomena)”“应力分析(stress analysis)”“胸腰椎骨折(thoracolumbar fractures)”“脊柱骨折(spinal fractures)”,最终纳入55篇文献。结果与结论:①通过有限元法对不同病因(骨质疏松性、创伤性、病理性)导致的胸腰椎骨折进行探索,有利于对各种类型胸腰椎骨折的生物力学特征有更加深刻的认识,完善对胸腰椎骨折的个性化和精细化治疗;②单一样本或数量较少样本的有限元分析具有偶然性,未来的有限元分析需要更大的样本数量来减少样本偶然性带来的误差;③仅骨骼的刚性结构不能满足实物的完整性所具有的生物力学工况,未来的有限元模型需要尽可能纳入实物的所有结构(例如肌肉、韧带等软组织);④有限元法在骨质疏松性和创伤性胸腰椎骨折方面的研究较多,未来需要进行更加深入的研究;病理性胸腰椎骨折领域的研究较少,未来研究范围较广。

有限元法构建退行性脊柱侧弯模型:病因与治疗中的生物力学分析

背景:退行性脊柱侧弯是指发生在成年之后,脊柱冠状面Cobb角度>10°伴有矢状面畸形和旋转脱位,常常产生脊髓、神经受压症状,如腰疼、下肢疼痛、麻木、无力、神经源性跛行等。有限元法是一种计算机建模的力学分析技术,通过建立数字化网格模型,能真实还原人类脊柱模型并可进行脊柱力学研究。目的:综述有限元法在退行性脊柱侧弯病因及治疗中的应用。方法:在文献数据库中国知网、PubMed、Web of Science中检索2023年10月之前发表的有关有限元分析法在退行性脊柱侧弯中应用的文献,英文检索词为finite element anaysis,biomechanics,stress analysis,degenerative scoliosis,adult spinal deformity,中文检索词为有限元分析法、生物力学、应力分析、退变性脊柱侧凸、成年性脊柱侧凸。最终纳入文献54篇。结果与结论:①运用有限元法构建的退行性脊柱侧弯模型得出的生物力学研究结果,与体内试验研究结果相同,证明有限元法在退行性脊柱侧弯中具有较高的实用价值;②通过有限元法对退行性脊柱侧弯的病因与治疗进行研究,有利于预防其发生、减缓其进展、制定出更合适的治疗方案、减少手术并发症出现、促进患者术后康复等;③有限元法从材料单一的骨性结构逐渐发展到纳入肌肉韧带等软组织的阶段,且小样本含量越来越无法满足研究需要;④有限元法在退行性脊柱侧弯领域有较大的发展空间。