Albino mice are animals commonly used for experimental studies on malaria. It is very necessary to find a strain of mice most susceptible to the P. yoelii-A. stephensi system. Thus, experimental studies were carried out on 9 inbred strains of mice (SMMC/A, SMMC/B, SMMC/C, SMMC/D, C57BL, C3H, 615, SMMC/C?615, Jin-bai N0.1)and one outbred strain (Kuming strain) by means of both sporozoite-and blood-induced infections. The results obtained are summarized as follows.(1) Although all of the 10 strains became patent after blood inoculation, producing an infection rate of 100%, yet there exists a very significant difference in susceptibility to sporozoite-induced infection between different strains of the test mice. Six strains of them including SMMC/C were found most susceptible to infection, reaching 100% patency. (2) As compared with others, the SMMC/C strain had the shortest prepatent period (4.22?0.43 days) with the least difference in the time of first appearance of the parasites in the circulating blood amongst individuals of this strain. (3) When the anopheline mosquitoes fed on each of the 10 strains, SMMC/C strain was found most infective to the vector with the gland infection rate of 73.20?5.9%. From all the results obtained, with A. stephensi as its transmitter, out of the 10 strains the SMMC/C is considered the most susceptible and suitable animal model for experimental studies on rodent malariaThe observations made on the SMMC/C mice showed the following results. (1) Five thousand sporozoites per mouse intraporitoneally inoculated were required to ensure an infection rate of 100%. (2) More than 90% of the mice became infected following intraporitoneal inoculation of the sporozoites which were preserved in the glucose normal saline mixed with albino rat serum (1:1 in ratio) either at 3-5? or at 23-25? up to 24 hrs after dissection from the mosquitose. (3) Ambient temperature of 18-20℃ was most favourable to development of the parasite in the mice. (4) Young mice were most susceptible to the sporozoite-induced infection, the adult being second to them.All the experimental results obtained are discussed.

[Objective]To study the effect of sixpetal clematis root injection(WLX)on histology,collagen phenotype and ultramicrostructurc in cartilage of osteoarthritis animal model.[Method]OA model animals were randomly divided into 3 groups:group S,group D and group K.Animals in group S received WLX and animals in group D received sterilized normal saline intramuscularly,group K was control and received nothing.After the animals were killed,cartilage specimen were obtained and sections were made and stained with HE/SOFG for Mankin score;the expression level of collagen Ⅰ and Ⅱ in matrix was tested by immunohistochemistry;change of ultramicrostructure of cartilage was observed with transmission electron microscope.[Result]Mankin score in group S was better than that in group D and K at each test period;result of IHC shows that positive stain area of collagen Ⅰ was lower in group S than that in group D and K,and positive stain area of collagen Ⅱ was higher than that in group D and K at each test period;cartilage impairment degree in group S was lower than in group D and K,and impairment manifestation in group D and K was similar on the whole.[Conclusion]sixpetal clematis root injection may protect articular cartilage by maintaining and promoting the chondrocyte synthesizing proteoglycan and type Ⅱ collagen.

Objective To explore the effect of the treatment for the old deltoid ligament injuries by TwinFix suture anchors fixation along with overlap suturing.Methods Totally the data of 17 patients with old deltoid ligament injury was retrospectively reviewed who received treatment from January 2007 to December 2011.There were 11 males and 5 females,with an average age of 32.1 years (range,18-58 years).All of them had ankle sprain histories with the duration ranging from 7-25 months (average,14.2 months).All patients received weight-bearing X-ray,bilateral anterior-posterior (AP) and oblique radiography,MRI and ultrasound examinations before operation.Further arthroscopic examination was performed to confirm the diagnosis and debrided the intra-articular proliferative synovial tissue as well as injured articular cartilage for the patients after they were diagnosed with deltoid ligament injury.Open surgeries were performed though an incision on the medial ankle space.Residual ligament and scar tissue were cleaned.Old avulsion fractures of medial ankle tip were removed in 2 cases.The deep layer of ruptured deltoid ligament was sutured onto the tip of medial malleolus while the superficial layer was overlapped and sutured to the periosteum of medial ankle.Anchors were then utilized to fix the ligament.The clinical outcomes were evaluated based on American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hiodfoot score system.Results The follow-up duration of the 17 patients were 12-34 months with an average of 20.1 months.Both image evidences and intraoperative findings revealed the injury and scarring of deltoid ligament.The angle between long axis of talus and first metatarsal and the angle of hindfoot alignment in Saltzrnan view reduced from 5.4°±1.8°,8.2°± 2.6° before surgery to 4.0°±0.9° and 5.3°±1.3° after surgery respectively.The mean AOFAS hindfoot score before operation was 76.8±7.0 and increased to 94.1±3.3 at the last follow-up.There were ten cases receiving excellent effect,6 good and 1 moderate.The good and excellent rate was 94.1％ (16/17).All the 17 patients achieved paiu relief and none had recurrent injury till the last follow-up.Conclusion TwinFix suture anchor fixation along with overlap suturing was an effective way in dealing with old deltoid ligament injury cases.

BACKGROUND: Operative correction of hallux valgus is one of the most procedures in foot and ankle department, but postoperative plaster slab immobilization often brings great inconvenience and pain. Off-loading forefoot shoes can theoretically help them to do activities off bed early, and prevent loading on the forefoot during walking. But its advantages and disadvantages compared with plaster slab are still unknown.OBJECTIVE: To compare the clinical effects of over-the-toe plaster slab and off-loading forefoot shoes after hallux valgus correction.METHODS: Patients with hallux valgus undergoing distal Chevron osteotomy or Scarf osteotomy in the Huashan Hospital of Fudan University between May 2012 and October 2013 were retrospectively reviewed. Group A patients had a below-knee and over-the-toe plaster slab while Group B had an off-loading forefoot shoe applied after surgery.Radiological assessment was done at 6 weeks postoperatively. Immobilization was removed once bone union was indicated. Clinical scales and subjective satisfaction investigation were performed at final follow-up, and complications during follow-up were noted. All values between groups were analyzed statistically.RESULTS AND CONCLUSION: Totally 125 patients (157 feet) were completely followed up, including 83 patients (95 feet) in Group A and 42 patients (62 feet) in Group B. There was no significant difference in demographics, pre-and-post operative radiological assessments, clinical scale, union time or general satisfaction rates between two groups. However,Group B patients had less chance to suffer metatarsophalangeal joint or inter-phalangeal joint stiffness, restricted ankle motion and supra-ankle pains of operated side in comparison with Group A (P < 0.05), and were more willing to accept the same treatment if they could choose again (P < 0.05). Compared with the plaster slab, the application of off-loading shoes not only maintains correction level, but also reduces such complications as stiffness or restricted motion of the joint, limb pains and so on, which makes patients more likely to accept, and should be given priority to in the rehabilitation following hallux valgus correction.

Objective To evaluate the ankle stability on lateral malleolar rotational models based on three-dimensonal CT reconstruction and volume rendering technique.Methods Eighteen cadaveric specimens were utilized in the study (male 11;female 7; 68.2 years in average) and were divided into 2 groups in which the first group only cut the anterior tibiofibular ligament and defined as intact deltoid ligament group.Another group additionally cut the deltoid ligament and defined as deltoid ligament injured group.Fibular transverse osteotomy was performed at 3 cm proximal to the ankle joint and lateral malleolar rotational malunion model of 5°,10°,15° and 30° were built in every specimen.CT scanning was performed for each model then and all CT data were imported into Mimics 10.01 software.The structures of distal syndesmosis,ankle mortise as well as talus in the mortise were outlined by automatic dense identifying and manually modified later.Three-Dimensional models of these structures and their volume were outputted in the software.The volume of ankle clear space was calculated as the difference value of ankle mortise and talus in the mortise.Ankle stability was reflected by comparison of these volumes to the normal condition.Results With the rising of malrotational degree,the volume of inferior syndesmosis and mortise were increased and the volume of talus in the mortise was reduced.In the deltoid ligament intact group,10° of malrotation would significantly enlarged the volume of distal syndesmosis and ankle clear space when compared to normal condition.However,in the deltoid ligament injured group,5° of rotational deformity would significantly enlarge the volume of ankle clear space and distal syndesmosis.Conclusion The condition of deltoid ligament has significant impact on ankle stability in cases of lateral malrotional deformity.Distal syndesmosis and ankle clear space were significantly enlarged at 10° malrotation deformity.However,additional deltoid ligament injury can significantly reduce ankle stability at just 5° of distal fibular rotational deformity.

Objective Purpose of this research is to biomechanically compare the screw-fixed and plate-fixed posterior malleolus fracture in osteoporosis patients with fatigue loading system and space motion system in simulation gait cycle,and to give a theory evidence on how to choose an internal fixation in osteoporosis patients with posterior malleolus fracture.Methods 72 osteoporotic cadaveric lower limbs were prepared to simulate Haraguchi Ⅰ posterior malleolus fracture and randomized into 2 groups with 36 each.Screw group were fixed with 2 paralleled 4.0 mm titanium partial thread cancellous screws from posterior to anterior.Plate group were fixed with plate.Based on the ratio of fracture area on sagittal plane to distal tibial articular surface (S),the two groups were subdivided into three subgroups,named as screw group A,plate group A,screw group B,plate group B,screw group C,plate group C.S (screw group A,plate group A)=l/4;S (screw group B,plate group B)=1/3;S (screw group C,plate group C)=1/2.According to the height of fracture fragments,these 6 subgroups were further divided into subgroup "a" with height 19.3mm and subgroup "b" with height 39 mm.Furthermore,4 different conditions of gait cycle were simulated as follows:1) specimen was loaded with 3.2 body weight (BW) at dorsiflexion angle of 12°;2) Start-up phase:dorsiflexion angle of 5°,3 BW;3) neutral position,3.6 BW;4) maximum plantar flexion,angle of 12°,4.5 BW.At the end of repeated loading,the displacement of fracture fragment was measured with space motion system.Results At dorsiflexion 12° and plantar flexion 15°,there was a significant difference of displacement between screw and plate group with a larger displacement in screw group,whatever S or H was.When ankle was at dorsiflexion of 5°,the displacement showed significant difference between screw group Aa and plate group Aa,screw group Ba and plate group Ba,screw group Bb and plate group Bb,screw group Cb and plate group Cb,with a larger displacement in screw group.In neutral position,the differences were significant with a larger displacement in screw group,except between screw group Bb and plate group Bb.Conclusion Plate can provide stronger fixation for osteoporosis patients with posterior malleolus fracture in most situations,but both of the two methods cannot provide stable fixation when posterior malleolus fragment was in a too big area or height.

Objective To propose a CT classification of die-punch fragments in posterior pilon fracture and to explore its significance in helping the surgery.Methods ACT scan classification of die-punch fragments in posterior pilon fracture into 5 types was proposed according to their size and location.A retrospective study was conducted of the 48 posterior pilon fractures which had been treated at Department of Orthopaedics,Huashan Hospital from January 2013 to December 2015.They involved 16 men and 32 women,aged from 20 to 87 years (average,46.5 years).According to the preoperative CT scan classification of die-punch fragments,16 cases (33.3％) belonged to type Ⅰ,2 (4.2％) to type Ⅱ,18 (37.5％) to type Ⅲ,10 (20.8％) to type Ⅳ and 2 (4.2％) to type Ⅴ.Choice of operative approach,reduction and internal fixation and removal of the fragments were guided by the CT classification of die-punch fragments.Their postoperative ankle functions were evaluated with American Orthopaedic Foot and Ankle Society (AOFAS) and visual analog scale (VAS) scoring systems.Results All the 48 cases were followed up for 11 to 21 months (average,13.7 months).Their AOFAS scores for ankle-hindfoot at the final follow-up ranged from 77 to 92 points,averaging 84.3 points;their VAS scores ranged from 0 to 1 point,averaging 0.2 point.There were no significant differences in their postoperative AOFAS scores for ankle-hindfoot or in their postoperative VAS scores between the types of die-punch fragments (P ＞ 0.05).No complications were recorded except superficial infection at the posteromedial wound of the ankle in 2 cases,tarsal tunnel syndrome in 2 cases,and sural nerve irritation in 2 cases.Conclusion It is feasible and effective to classify the die-punch fragments in posterior pilon fracture according to their size and location on the CT scan,because the classification can help choose an appropriate operative approach and manage the die-punch fragment,leading to fine clinical outcomes.

Objective To explore the outcomes of computer-assisted design of therapeutic personalized footwear for diabetic foot.Methods Fifty-eight cases of diabetic foot were included in the study.Ten items of data from theses patients were measured with methods provided by Salford University.All characteristics of the footwear were calculated with computer.Shoes were specially designed with the formula and computational method provided by Safford university.All patients had worn the shoes for 13 months.Special questionnaires were used to measure the outcomes.Results Thirty-two cases had been followed up for one month,25 cases for 2 months,25 cases for 3 months and 42 cases for 13 months.The score had improved from 67.94±15.14 before wearing the shoes to 78.13±1.44 thirteen months after wearing.The health score of the foot had improved.There was significant difference between before and after wearing the footwears.Conclusion Special-designed diabetic shoes play an important role in the prevention of ulcer for diabetic foot patients.Computational method and data model obtained from Salford university needs to be modified when applying it for Chinese.

Objective: To setup a custom-made gait simulator, and to provide an efficient tool for biomechanics research of ankle and foot. Methods: From November 2017 to April 2018, a total of 6 fresh frozen specimens of the foot and ankle were collected. The donated specimens, free of diseases in the foot and ankle part, were from the Department of Anatomy, Shanghai Medical College of Fudan University. Donors were 3 males and 3 females, aged from 48 to 69 years old, with an average age of 58.8 years old. The nine tendons in the foot were divided into 4 bundles, including anterior group comprised of tibialis anterior (TA), extensor hallucis longus (EHL) and extensor digitorum longus (EDL). Posterior group comprised of Achilles's tendon (AT). Medial group comprised of tibialis posterior (TP), flexor hallucis longus (FHL), and flexor digitorum longus (FDL). Lateral group comprised of peroneus brevis (PB) and peroneus longus (PL). A custom-made gait simulator was set up by using four independent electro motors to actuate 4 bands of tendons in the foot and another six motors to control tibia to achieve 6 degree-freedom parallel mechanism. And a hydraulic machine was used to provide axial pressure along tibia. Gait cycle of six fresh frozen cadaver feet was reproduced using this machine, and the kinematics data of ankle movement and ground reaction force (GRF) data was collected. By comparing the data above with the normal human gait data, the simulation results were analyzed to explore the clinical usage of this machine. Results: On the sagittal plane, the ankle appeared to plantarflexion at the beginning of gait, and then turned to dorsiflexion after the max plantar flexion (about 10°) at 18% of gait cycle. At the 40% gait cycle, ankle joint was in neutral position and reached its max dorsiflexion (about 22°) at 83% gait cycle. On the coronal plane, ankle joint appeared inversion at the beginning and eversion afterwards with 10° range of change. On the horizontal plane, movement of ankle joint was small. Results showed that the first peak of vertical ground reaction force can reach to 1.1-1.3 times of bodyweight at 25% of gait cycle and the second peak appeared little lower at 70% of gait cycle. The GRF in posterior direction reached its peak at 30%, and then turned to anterior with its peak at 83% gait cycle. The GRF had small variation at the internal to external direction.All of the coefficients of multiple correlations (CMC) of GRF and ankle joint movements were close to or greater than 0.90. Conclusion This custom-made gait simulator has good gait simulation ability with high intra repeatability in respect of ankle rotation and ground reaction force, and can satisfy the request for ankle and foot biomechanics research.

Objective: To explore the mid-term efficacy of derotation of talus and medial column fusion for stage II-V Müller-Weiss disease (MWD). Methods: Data of thirty-six patients (38 feet) with MWD treated by derotation of talus and talona-vicular (TN) or talonavicular-cuneiform (TNC) arthrodesis in our center during January 2008 to December 2016 were retrospective-ly analyzed. There were 3 males (3 feet) and 33 females (35 feet) with an average age of 54.0±9.2 years old (range, 32-80 years old); there were 11 right feet and 27 left feet. According to Maceira and Rochera staging system, there were 9 stage II cases, 11 stage III cases, 10 stage IV cases and 8 stage V cases. The external rotation of talus was intensively focused. After the TN articular surface was debrided, an "H" shape plate and a hollow lag screw were used to firmly fix the TN or TNC joint. American Orthopae-dic Foot and Ankle Society Scale (AOFAS), visual analog scale (VAS) and relative radiological parameters were evaluated preoper-atively and during follow-up. Results: The mean follow-up duration was 37.2 months (range, 25-113 months). The latest follow-up showed satisfactory outcomes. Overall, AOFAS score was improved from 41.3±11.3 points (range, 20-56 points) preoperatively to 85.5±7.1 points (range, 68-100 points) postoperatively (Z=5.16, P< 0.001), and the VAS score was reduced from 5.6±1.5 points (range, 3-8 points) preoperatively to 0.8±1.2 points (range, 0-4 points) postoperatively (Z=5.19, P< 0.001). These differences of functional score and pain evaluation were statistically significant. The Tomeno-Méary angle decreased from-6.6°±12.2° to 0.5°±2.9° (Z=3.43, P=0.001); the calcaneal pitch angle increased from 13.5°±3.9° to 22.1°±3.4°(t=10.12, P< 0.001), and the talarnavic-ular coverage angle decreased from 27.1°±5.9° to 7.6°±3.3°(Z=5.16, P< 0.001). The AP talar-first metatarsal angle decreased from-16.0°±10.7° to-7.0°±8.5°(t=5.49, P< 0.001). The differences of radiological parameters were statistically significant. Conclusion The mid-term results showed that the TN or TNC joint fusion could achieve a favorable clinical and radiological outcome for MWD patients. Even for the patients with severe deformities (stage II-V), such treatment strategy could also achieve satisfacto-ry deformity correction and functional improvement. Intraoperative restoration of talus rotation is the key to normal alignment of the subtalar joint/TN joint.