Lower leg lengthening has a history of more than 100 years. However, serious complications occurred in the early stage due to the immature device and technical conditions. The emergence of Ilizarov technology making limb lengthening is a kind of controlled operation. Based on the "Ilizarov effect", the results of limb regeneration and lengthening were obtained by slow, stable and continuous distraction of living tissues. The regeneration of bone and soft tissue is like limb development in children. Currently, the traditional Ilizarov external fixation is still the dominated method for leg lengthening. The Chinese Ilizarov external fixator and the lower leg Achilles tendon elastic lengthening external fixator are the representatives of domestic application. Other limb lengthening methods, including computer hexapod assisted orthopedic surgery (CHAOS), lengthening over nail (LON), lengthening and then nailing (LATN) and intramedullary nail lengthening system, have not been developed in China. Percutaneous transverse osteotomy at 5-6 cm below the tibial plateau is a common osteotomy method in China. This method can maximize the retention of periosteum and intramedullary blood circulation. Limb lengthening more than 4 cm is recommended by leg Achilles tendon elastic synchronous lengthening fixator with calcaneal wire fixation. Following the principle of tension-stress, the lengthening is carried out slowly. Further, the lengthening device is removed step by step according to the principle of dynamic adjustment of fixed stiffness.

Objective To analyze the causes of the complications in the treatment of limb deformities with the Ilizarov technique and to discuss the management and prevention of these complications.Methods From January 2000 to October 2010,846 patients with limb deformities (16 upper limbs and 830 lower limbs) who had been treated with Ilizarov technique were retrospectively analyzed,including 508 males and 338 females with an average age of 25.7 years (range,1.2-72).Statistical analysis was used to compare the type,severity,treatment methods and results of complications.Results Postoperative follow-up lasted for 6 to 30 months,with an average of 18 months.There were 81 cases of pin tract infections,36 cases of restricted joint movements,6 cases of skin thermal damage,7 cases of nerves and vessels injury,8 cases of bone delayed union,2 cases of osteofascial compartment syndrome,7 cases of dislocation,5 cases of fixed needle breakage,8 cases of secondary joint deformities,5 cases of serious osteoporosis,6 cases of skin eruption,4 cases of femoral fractures near to proximal external fixator,3 cases of subsequent fracture after external fixator dismantled,11 cases of deformity recurrence and 1 case of the others.Combining with anti-infection,functional training,physiotherapy,and the second operation therapy and so on,a permanent disability was finally left in 13 patients.Conclusion If the Ilizarov technique was used improperly,there would be multiple complications during the preoperative preparation,surgical procedures and postoperative management.Effective preventive measures should be taken,such as following the principle of the Ilizarov technique,standardizing operation procedures,strictly postoperative observation,correcting postoperative rehabilitation exercise guidance,regular follow-up radiography and postoperative adaptability dynamic adjustment of the external technique.

Objective: To investigate the cause of an incident of occupational contact dermatitis in a farm in Tianjin Prefecture, so as to provide insights into occupational safety. Methods: The disinfection process, use of disinfectants and individual protective measures in this farm were collected, and a field epidemiological investigation was conducted to collect the demographic characteristics, history of occupational contact, clinical symptoms, diagnosis and treatment data, and onset of disease among individuals with the same type of job. The cause of this incident was analyzed. Results: There were ten interns exposed to potassium hydrogen sulfate compounds simultaneously in this farm, and then, nine interns developed skin flushing across the body, and swelling and itching of the skin. Among these ten interns, five individuals were admitted to hospitals because of severe symptoms and were then clinically diagnosed as systemic contact dermatitis. All five individuals were cured following treatments. Epidemiological survey showed that all cases had a definite history of occupational contact with potassium hydrogen sulfate compounds but without use of any protective agents. In addition, there were thirty-five individuals with the same type of job in this farm that developed similar symptoms when they joined in the disinfection for the first time, and these individuals were self-cured following cessation to contact; however, recurrence of symptoms was found following contacts again. Conclusion This is a cluster of occupational contact dermatitis caused by exposure to potassium hydrogen sulfate compound.

Objective:To investigate surgical methods and clinical effects of tibial pseudarthrosis due to neurofibromatosis type I (NF1) in adult using Ilizarov technique combined with intramedullary nail.Methods:A total of 12 adult with tibial pseudarthrosis due to NF1 treated by Ilizarov technique combined with intramedullary nail from October 2009 to December 2017 were retrospectively included. There were 6 males and 6 females with an average age of 27±8.3 years (range 17-44). All cases presented severe anterior arch in varus or valgus deformity with shortening in an average of 10.8±3.7 cm (range 5.6-16.5 cm). The in-volved levels were at the middle and lower part of tibia. All cases suffered from more than one treatment with failed surgery. One male patient with 5 times of unsuccessful operations. There were 4 cases with severe limping gait and 8 cases with walking with the help of brace (or single crutch) preoperatively. Regarding the family history, seven cases were inherited by father and 5 cases by mother. During surgery, the part of tibial pseudarthrosis and thickened fibrous tissue surroundings like periosteal were removed. The contracture achilles tendon was elongated in open way, and intramedullary nailing cross the ankle joint was applied when the tibial medullary cavity opened. Further, iliac bone grafting and proximal tibial osteotomy were performed with Ilizarov fixator application finally. The tibia was lengthened at a rate of 0.5-1 mm/d at 7 days postoperatively. The healing rate of pseudarthrosis and the length and alignment of limb were evaluated by X-ray routinely. The lower limb function and complications were assessed by self-made table for lower limb deformity correction and functional reconstruction.Results:All patients were followed up for 31-80 months with an average of 47.6±14.7 months. Bone union of pseudarthrosis in all cases was eventually achieved. The tibia was lengthened 5-12 cm with an average of 8.4±2.5 cm. There were 9 cases underwent second surgeries to promote bone healing and to correct residual deformities. The external fixator was used for 25-37 months with an average of 31.5±3.7 months. There was no complication, including neurovascular injury, severe soft tissue or bone infection affecting the clinical effects. All intramedullary nails were not removed finally. The limb function and gait in full weight bearing in 12 patients recovered at the latest follow-up. The evaluation score was 2.4±0.3 (range 2.1-2.8), of which 9 cases were excellent 3 were good. Thus, the excellent and good rate was 100%.Conclusion:The satisfactory clinical effects, including angular deformity correction, pseudarthrosis healing and short limb lengthening, can be achieved in adult with tibial pseudarthrosis due to NF1 by using the combination method of Ilizarov technique and intramedullary nail. However, the treatment duration could be longer.

The Leucine-rich repeats and immunoglobulin-like domains-2 (LRIG2) gene expression in pituitary adenoma and its correlation with tumor invasiveness were studied. The expression of LRIG2 mRNA and protein in human pituitary adenoma obtained surgically was detected by RT-PCR (39 cases) and immunohistochemical staining (30 cases). It was found that LRIG2 was mostly localized at the nucleus of the pituitary adenoma cells. Its expression was significantly higher in the invasive cases than in the non-invasive cases. LRIG2 protein was positive in 14 cases out of 21 cases of invasive adenoma, but only 2 cases were positive in 9 cases of non-invasive adenoma. The positive expression rate of LRIG2 mRNA was 91.3% in invasive cases (total 23 cases) and 62.5% in non-invasive cases (total 16 cases), respectively. LRIG2 gene is overexpressed in invasive pituitary adenoma. It may play an important role in pituitary adenoma invasiveness and further studies are necessary to elucidate the mechanism under this phenomenon.

Objective To quantitatively assess severity of movement disability by analyzing physical activities recorded by an actigraph monitor in patients with neurology disorders.Methods Eighty-one patients with Parkinson' s disease(PD)and 61 patients with acute cerebral infarction(ACI)accompanying impaired upper limb motor function were included in the study.PD patients and ACI patients were treated using the international PD and ACI treatment guidelines,respectively.The patients were asked to wear an Actigraph monitor for 6 days before the treatment in both PD and ACI patient groups and at 24-38 days post-treatment in PD patients or at 28 days post-treatment in ACI patients.The recorded data was analyzed by power-law exponent(PLE)and detrended fluctuation analysis(DFA).Clinically,before and after the treatments,PD patients were evaluated using the conventional Unified Parkinson Disease Rating Scale (UPDRS),and ACI patients were evaluated by assessing upper limb motor function using Fugl-Meyer Assessment(FMA)and Functional Independence Measure(FIM).The correlation of the UPDRS scores with PLE was analyzed in PD patients,and the correlation of FMA or FIM with DFA in ACI patients.Results Both the UPDRS scores and the PLE values in PD patients were improved after the drug administration(UPDRS total:32.8 ± 16.2 and 28.8 ± 14.7,Z =2.080,P =0.038; UPDRS Ⅲ:18.6 ± 8.2 and 15.7±6.8,Z=2.155,P=0.031; PLE:0.98 ±0.25 and 0.82 ±0.21,Z=2.212,P=0.027,before and after the treatment,respectively).There were a linear correlation coefficient of 0.699 between the improvements of total UPDRS scores and the PLE values,and of 0.823 between the UPDRS Ⅲ and the PLE values.FMA,FIM scores and DFA were improved significantly than before treatment(FMA:12.39 ± 8.21 and 30.28 ±7.29,Z=3.016,P =0.004; FIM:8.98 ±7.29 and 13.21 ±7.6,Z =2.282,P=0.038; DFA:0.86 ±0.31 and 0.98 ±0.27,Z =2.360,P =0.036,before and after the treatment,respectively).It also showed linear correlations between the improvements of FMA scores and DFA(r =0.638),and between FIM scores and DFA(r =0.712,both P ＜0.05).There was no correlation between UPDRS scores and DFA values in PD patients,nor between FIM scores or FMA scores and PLE values in ACI patients.Conclusions Actigraph device can be used to monitor patients activity in movement disorders.Analysis of its PLE can provide a quantitative evaluation in PD while its DFA may provide useful specific assessment of impaired upper limb motor function in ACI patients.It can also be used in quantitatively assessing new drug efficacy.

The Soviet Union orthopedic doctor Ilizarov invented the ring external fixator which could be assembled into more than 800 configurations, and created a new minimally invasive external fixation technology system called Ilizarov technology which was different from the western classical orthopedic technique. The theoretical basis of this technique is to imitate nature, by controlling and transforming the stress of life movement in vitro, to cure the complex trauma fracture, bone and soft tissue defect, infection and severe deformity of limbs, and to save some endangered amputation complex trauma and limb deformity. From theoretical guidance, surgical indications, medical models and postoperative management, it differs from the modern technique of internal fixation (AO) fracture treatment theory in trauma orthopedics. It can achieve fracture reduction and fixation by the most minimally invasive or even bloodless operation, and control bone growth in vitro. It can not only complete the fixation requirements of most fractures in trauma orthopedics, but also solve complex problems such as bone nonunion, bone defect, soft tissue defect of limbs and associated malformation without bone graft and loss of bone length. Ilizarov technology was introduced into China mainland for more than 30 years, but the application of this technology in the field of orthopaedics in China is still not extensively spreaded because of many reasons, In this article, the authors review the application of Ilizarov technology in the field of trauma orthopedics in China for domestic Orthopaedic surgeon to better understand this technology.

Objective To analyze the applicability of different risk assessment methods in assessing laboratory benzenes exposure. Methods The work positions exposed to benzenes (benzene, toluene, xylenes) of a chemical catalyst research and development company were selected as the research subjects. An occupational health field survey was conducted, and the benzenes exposure levels of the lab personnel were measured. Qualitative assessment method, comprehensive index method, quantitative assessment method, and occupational hazards classification method were used to evaluate the occupational health risk on benzenes exposure in the laboratory personnel. The applicability of different assessment methods was compared. Results The occupational health engineering protection measures and management system of the company need to be further implemented. The benzene exposure level of benzene hydrogenation laboratory personnel exceeded the national standard, with the exposure concentration of time weighted average (C_TWA) of 5.00 mg/m³ and short term exposure concentration (C_STE) of 10.50 mg/m³. The C_TWA and C_STE of toluene and xylenes exposure were both lower than the minimum quantitative concentrations. The results of different risk assessment methods varied. The qualitative assessment method indicated higher level of occupational health risk of benzenes, while the comprehensive index and hazard classification methods indicated consistent result on lower level of benzenes. For occupational health risk of benzene, the standardized risk ratio (RR) levels corresponding to the qualitative and quantitative assessment methods were both extremely high risk. The RR levels of benzene exposure assessment using the comprehensive index method and the occupational hazards classification method were high, while the corresponding RR levels of exposure to toluene and xylenes were both low. Conclusion Attention should be paid on the health risks of benzene exposure to benzene hydrogenation laboratory personnel. When benzene exposure level is below the national occupational exposure limit, occupational hazards classification method is not recommended for health risk assessment for benzenes. The comprehensive index method is preferable when more comprehensive occupational health information is available, as it provides a more objective and comprehensive evaluation on occupational health risks of benzenes.

The Leucine-rich repeats and immunoglobulin-like domains-2 (LRIG2) gene expression in pituitary adenoma and its correlation with tumor invasiveness were studied.The expression of LRIG2 mRNA and protein in human pituitary adenoma obtained surgically was detected by RT-PCR (39 cases)and immunohistochemical staining (30 cases).It was found that LRIG2 was mostly localized at the nucleus of the pituitary adenoma cells.Its expression was significantly higher in the invasive cases than in the non-invasive cases.LRIG2 protein was positive in 14 cases out of 21 cases of invasive adenoma,but only 2 cases were positive in 9 cases of non-invasive adenoma.The positive expression rate of LRIG2 mRNA was 91.3％ in invasive cases (total 23 cases) and 62.5％ in non-invasive cases (total 16 cases),respectively.LRIG2 gene is overexpressed in invasive pituitary adenoma.It may play an important role in pituitary adenoma invasiveness and further studies are necessary to elucidate the mechanism under this phenomenon.

Objective:To investigate the application value of joint friction sounds in diagnosing meniscus injury of the knee based on machine learning models.Methods:A case-control study was conducted to analyze the clinical data of 17 patients with meniscus injury of the knee (meniscus injury group) admitted to Sir Run Run Shaw Hospital Affiliated to Nanjing Medical University from August 2020 to October 2022, as well as 75 recruited healthy subjects without knee joint diseases (healthy group). The knee joint friction sounds of the subjects were collected in a relatively quiet environment (peak value below 40 dB). The sounds collected in a flexion-extension-flexion mode of exercise were split and divided randomly with a ratio of 4∶1 into the training set (125 segments from the meniscal injury group and 187 segments from the healthy group) and the test set (33 segments from the meniscal injury group and 47 segments from the healthy group). The sounds obtained in a sit-stand-sit mode of exercise were split and divided randomly with a ratio of 4∶1 into the training set (81 segments from the meniscal injury group and 164 segments from the healthy group) and the test set (20 segments from the meniscal injury group and 40 segments from the healthy group). Four machine learning models were built, including support vector machine with linear kernels, radial basis function support vector machine, random forest, and extremely randomized trees. The learning training of the model was performed on the training set, and its model performance was verified with the test set. The time required in a single collection of joint friction sound from the subjects and the interpretation of data analysis was recorded. Knee function of the subjects were scored according to the Lysholm Score before and at 1 day after the test. The accuracy rates of diagnosis of meniscus injury with friction sounds under the two modes of exercise were compared based on the test results to yield an optimal one. The effectiveness of the four models was compared to find the best machine learning model fitting the data frame of this study according to the test results such as accuracy, sensitivity, specificity, F1 score, and area under the receiver operating characteristic curve (AUC) obtained with the optimal mode of exercise. The diagnostic accuracy, misdiagnosis rate and missed diagnosis rate of joint friction sound for meniscal injury under the optimal machine learning model with the optimal mode of exercise were observed.Results:The time required in a single collection of joint friction sound ranged from 5 to 10 minutes [(7.1±1.3)minutes], when the time required for interpretation of data analysis was approximately 1 minute. The Lysholm Score before and after the test was (75.6±4.0)points and (77.7±3.7)points respectively in the meniscal injury group ( P>0.05), and (99.6±0.9)points and (99.5±1.0)points respectively in the healthy group ( P>0.05). The diagnosing accuracy rates for flexion-extension-flexion of exercise and sit-stand-sit modes of exercise were 0.775 and 0.817 under the support vector machine model with linear kernels; 0.813 and 0.900 under the radial basis function support vector machine model; 0.800 and 0.867 under the random forest model; 0.800 and 0.900 under the extremely randomized tree model. The accuracy rates for sit-stand-sit mode of exercise were all higher than those for flexion-extension-flexion mode of exercise. In the sit-stand-sit mode of exercise, the extremely randomized tree model had an accuracy rate of 0.900, sensitivity of 0.900, specificity of 0.950, F1 score of 0.900, and AUC of 0.942, which were higher than those under the remaining 3 models, showing better machine learning efficacy. Under the extremely randomized tree model in the sit-stand-sit mode of exercise, 22 (18 true positive and 4 false positive) were diagnosed as meniscal injury and 38 (36 true negative and 2 false negative) as healthy out of 60 segments in the test set (20 from the meniscal injury group and 40 from the healthy group). The diagnostic accuracy of joint friction sounds in diagnosing meniscus injury of the knee was 0.900, with the misdiagnosis rate of 0.100 and the missed diagnosis rate of 0.100. Conclusion:Diagnosis of meniscus injury of the knee with joint friction sounds can shorten time and enhance safety during the examination process. The diagnostic model using machine learning-based artificial intelligence is faster and more stable, which can be used as a diagnostic marker for such injury.