Digital orthopedic technologies are increasingly being applied to the clinical practice of joint surgery. These technologies include artificial intelligence, virtual/augmented/mixed reality, 3D printing, computer navigation, robotic-assisted joint replacement surgery, and other digital orthopedic technologies. Digital orthopedic technologies continue to empower joint surgeons, simplify complex operations, achieve precision in simple operations, and to make precise operations more individualized. Thus, they are becoming important development directions for joint surgery in the future. With the help of advances in computer-aided design and additive manufacturing technology, customized joint prostheses and bone tissue repair materials provide great convenience for reconstruction of complex bone defects during revision surgery. Various types of computer-assisted navigation technologies and robot-assisted surgery technologies can help doctors improve the accuracy of osteotomy and prosthesis implantation significantly. However, to fundamentally improve patients' satisfaction after joint replacements, we need to use digital orthopedics technologies to explore the ideal target value of arthroplasty. Further, we use personalized preoperative planning with objective and accurate assessment technology of soft tissue balance, precise intraoperative operations, and the use of customized prostheses to achieve individualized and precise joint arthroplasty. Various digital orthopedic technologies have their own advantages and disadvantages. Joint surgeons should have an in-depth understanding of these technologies and make full and reasonable use of these technologies to benefit the majority of patients.

Objective To discuss the preliminary clinical results with computer navigation assisted minimally invasive total knee replacement. Methods Forty patients were recruited into this prospective study according to entry criteria and were randomly selected into either control group which treated with standard knee replacements or navigation assisted group which operated with navigation assisted total knee replacement using a minimally invasive midvastus approach. Incision length, blood loss, operation time, KSS scores at 6 weeks and 6 months, radiographic alignment and prosthesis position of these patients were analyzed. Functional outcomes were compared 6 weeks postoperatively. Results There were significant differences (P

Objective To analyze the MRI features of senile endometrial polyp and compared MRI features with pathological find-ings,to improve the ability for the diagnosis.Methods The study included 58 cases with senile endometrial polyp proved by diag-nostic curettage or hysterectomy.MRI and pathological findings were analyzed retrospectively.Results Among 58 cases,there were 46 cases with and 12 cases without uterine cavity enlargement.Lesion combined solid portions with cryptomere cystics areas filled in uterine cavity in 35 cases,and MRI showed hypointensity on T1 WI,mixed intensity with hypointensity separation lines on T2 WI, and marked heterogeneous enhancement.The signal of uterine cavity was heterogeneous in 23 cases with hypointensity or isointensi-ty on T1 WI,hyperintensity or isointensity on T2 WI,and no obviously enhancement.Conclusion MRI combined with clinical fea-tures can improve the diagnostic accuracy of senile endometrial polyp.

The s tr ucture of a micromovement external fixture for treatment of diaphyseal long bo ne fracture is presented in this paper.Minisize DC geared motor and screw drive are used to transmit the power.Micro controller is used to control the micromove ment extent and frequency.This device can give the fractured bone ends micromo vement stress stimulation,so as to improve the forming and calcifying of the ca llus,and to accelerate the fracture healing process.This device can be applied t o the research on micromovement treatment of bone fracture.

Finite element method (FEM)is a calculating method for stress and strain analysis in the field of mechanical engineering.FEM has already been used in the design of medical apparatus,especially of the fixer for fracture treatment.The external fixer taken as an example,the anti-compression,anti-blending and anti-torsion characteristics of a certain type of external fixer are analyzed using FEM.This paper shows that by using FEM,the mechanical property of medical apparatus can be revealed at the designing stage.The strength and rigidity weak pocket can be found,and thus the improvement and optimization of medical apparatus can be made.

Objective: To study the inhibition of antisense TRP1 on cell growth of malignant melanoma(MM) and explore a new way for therapy of melanoma. Methods: Antisense TRP-1 recombinant vector was constructed and transfected into MM cells. According to the results of MTT, cell growth curves were drawn and then clonogenic assay was performed in vitro. At last, tumorigenesis assay was undertaken in nude mice in vivo. Results: Cell proliferations of TRP-1 transfected MM cells were inhibited compared with the control cells. The results of clonogenic assay displayed the difference of clonogenic percentage between TRP-1 transfected MM cells (52% , P

Objective To compare the difference of therapeutic effect of surgical operation and non-operation for acute damnification of elbow ulnar collateral ligament in rabbits.Methods A total of 81 New Zealand rabbits were randomly and equally divided into three groups(27 rabbits per group),ie,Group A(control group):the ulnar collateral ligaments of right elbow joint were only enclosed;Group B:the ulnar collateral ligaments of right elbow joint were severed and sutured;Group C:the ulnar collateral ligaments of right elbow joint were severed,without suture.The biomechanics was detected at time intervals of 3 and 6 weeks.Results Twelve weeks after transplantation,the displacements of the ligaments in Groups B and C were(6.06±0.4)mm and(7.72±0.44)mm,with statistical difference(P ＜ 0.05).The displacement of the ligaments in Group A was(5.87±0.46)mm,which was similar to that of Group B(P＞0.05).The maximum loads of the ligaments of Groups B and C were(68.23±5.64)N and (42.45±3.66)N respectively,with statistical difference(P＜0.05).The maximum load of the ligaments of Group A was(72.86±2.99)N,which was similar to that of Group B(P ＞ 0.05).The rigidities of the ligaments of Groups B and C were(11.33±1.52)N/mm and(5.52±0.67)N/mm respectively,with significant difference(P ＜ 0.05).The rigidities of the ligaments of Group A was(12.49±1.44)N/mm,which was similar to that of Group B(P ＞ 0.05).The power consumption of the ligaments of Groups B and C were(0.206±0.017)J and(0.163±0.013)J respectively,with statistical difference(P＜0.05).The power consumption of the ligaments of Group A was(0.213±0.010)J,which was similar to that of Group B(P＞0.05).Conclusion Surgical operation is more effective than the non-operation in dealing with acute damnification of the ulnar collateral ligaments of elbow ulnar collateral ligament in rabbits.

Objective To investigate the safe zone and the soft tissue damage of two-incision minimally in-vasive total hip replacement,and to retrospectively analyze the clinical result.Method 20 adult cadavers(40 hips) were used for anatomic research.The Course of the later femoral cutaneous nerve was recorded.The angle between the intermission of the piriformis muscle and gluteus medius muscle with horizontal plane was also recorded.Analogue operation was taken on 3 fresh cadavers to assess the injury extent of soft tissues around incisions.27 cases under-went two-incision minimally invasive total hip replacement.Results LFCN was found potentially at risk as far as 6～71 mm medial to anterior superior iliac spine(ASIS)along the inguinal ligament,as much as 21～112 mm distal on the lateral border sartorius muscle from the ASIS.With the operative leg fully adducted,flexed over the nonopera～tire leg and the patella placed horizontal,the angle between the intermission of the piriformis muscle and gluteus medius muscle with horizontal plane is(60±5)°(range 55°-68°).Imitating modified two-incision THA on 3 freshhips revealed muscle contused on gluteus medius-piriformis muscle and gluteus minimus muscle.The average length of the anterior incision was 5.0 cm(4.6～6.5 cm)and of the posterior incision 3.7 em(3.0～4.2 cm).All of the patients were ambulant the day after surgery.Blood transfusion was carried out in 4 cases including one case of femo-ral neck fracture.The patients were followed up for 18 months(13～25 months).No other complications occurred.The mean Harris score was 94.5(92～96).Conclusion Front incision from the point inferior ASIS 3 cm and 1cmlater from ASIS vertically 6 cm should be chosen and the real incision should be 60°with horizontal plane.GIuteus medius,piriformis muscle and ghteus minimus muscle will be contused in two-incision minimally invasive surgeryto-tal hip replacement.Two-incision total hip replacement has the advantage of being muscle sparing and minimally in-vasive with less blood loss and rapid recovery.However,this technique is time consuming,technically demanding,and requires fluoroscopy.

Objective To investigate the probable pathologic basis of amido proton transfer(APT) imaging by analysing APT signal intensity and pathologic features of different grades of glioma.Methods Twenty-eight patients with glioma confirmed by postoperative pathology underwent APT scan.All the patients were divided into two groups,including 11 cases in low grade (WHO Ⅰ and Ⅱ) and 17 cases in high grade (WHO Ⅲ and Ⅳ) group.The APT rate of tumor core was measured.The specimens were processed with routine hematoxylin-eosin (HE) staining and immunohistochemistry of Ki-67 and CD34.Independent-samples t test was used to detect the difference of APT rate,cellularity,microvessel density and Ki-67 labeling indices of tumor core between low grade and high grade group.Pearson correlation analysis and multi-variable linear regression analysis were used to detect the relationship of APT rate with cellularity,microvessel density and Ki-67 labeling indices of the tumor core.Results The APT rate,cellularity and proliferation index were (2.3±0.6) ％,(9.4±2.4) ％ and (14.2±5.4) ％ in low grade group,while (3.6±0.7) ％,(18.4±4.7) ％ and (31.7±4.5) ％ in high grade group,respectively.Microvessel density was (19.0±7.4) per high-power field in low grade group and (38.9±11.3) in high grade group.There were statistical differences of the APT rate,cellularity,microvessel density and proliferation index between the low grade group and the high grade group (t=-4.94,-5.89,-5.13,and-9.28,respectively,P＜0.01).The APT rate was positive correlated with cellularity,microvessel density and proliferation index.The coefficient of correlation were 0.904,0.598,and 0.750,respectively,(P＜0.01).Multiple linear correlative analysis showed that increasing cellularity (X1),microvessel density (X2) and proliferation index (X3) were the main factors for increasing APT rate,and the correlation equation was Y=0.801 + 0.12X1-0.003X2 + 0.026X3 (F=46.437,P＜0.01,R2=0.853).Conclusions The APT signal intensity of the tumor core could reflect the pathologic features of glioma.The APT rate was positive correlated with cellularity,microvessel density and proliferation index,which indicate the higher APT rate the higher grade tumor.

Objective To investigate the anti-tumor effect of ultrasound-targeted microbubble destruction (UTMD) mediated herpes simplex virus thymedine kinase (HSV-TK) on mice ovarian cancer.Methods Forty female BALB/c-nu mice were randomly divided into four groups after the models of subcutaneous transplantation tumors were established:(A)HSV-TK + Microbubbles + Ultrasound (HSV-TK+ MBs + US);(B) HSV-TK+ Ultrasound (HSV-TK + US);(C) HSV-TK;(D) PBS.TheTK protein and mRNA expression were separately detected by western-blot and real time RT-PCR.TUNEL staining was used to detect the tumor cell apoptosis.The inhibition rates and survival time of the animals were compared among all groups.Results The HSV-TK gene transfection efficacy and tumor inhibitory effect of HSV-TK on mice transplantable tumor in group A (HSV-TK + MBs + US) were significantly improved compared with group B (HSV-TK + US),group C (HSV-TK) and group D (PBS) (P ＜0.05).However,group A has no significant difference (P ＞0.05) with other groups in improving the survival time of tumor-bearing mice.Conclusions Ultrasound-targeted microbubble destruction can effectively transfect HSV-TK gene into target tissues and play a significant inhibition effect on ovarian cancer in mice.However,this new method is not able to improve the survival time of mice for a short-term observation.