The method of directly using speed information and angle information to drive attractors model of grid cells to encode environment has poor anti-interference ability and is not bionic. In response to the problem, this paper proposes a grid field calculation model based on perceived speed and perceived angle. The model has the following characteristics. Firstly, visual stream is decoded to obtain visual speed, and speed cell is modeled and decoded to obtain body speed. Visual speed and body speed are integrated to obtain perceived speed information. Secondly, a one-dimensional circularly connected cell model with excitatory connection is used to simulate the firing mechanism of head direction cells, so that the robot obtains current perception angle information in a biomimetic manner. Finally, the two kinds of perceptual information of speed and angle are combined to realize the driving of grid cell attractors model. The proposed model was experimentally verified. The results showed that this model could realize periodic hexagonal firing field mode of grid cells and precise path integration function. The proposed algorithm may provide a foundation for the research on construction method of robot cognitive map based on hippocampal cognition mechanism.
Objective To summarize the progress of clinical diagnosis and treatment of diabetic Charcot neuroarthropathy (CNO) of foot and ankle to provide reference for clinical treatment. Methods The research literature on diabetic CNO of foot and ankle at home and abroad was widely reviewed, and the stages and classification criteria of CNO were summarized, and the treatment methods at different stages of the disease course were summarized. Results CNO is a rapidly destructive disease of bone and joint caused by peripheral neuropathy, which leads to the formation of local deformities and stress ulcers due to bone and joint destruction and protective sensory loss, which eventually leads to disability and even life-threatening. At present, the modified Eichenholtz stage is a commonly used staging criteria for CNO of foot and ankle, which is divided into 4 stages by clinical and imaging manifestations. The classification mainly adopts the modified Brodsky classification, which is divided into 6 types according to the anatomical structure. The treatment of diabetic CNO of foot and ankle needs to be considered in combination with disease stage, blood glucose, comorbidities, local soft tissue conditions, degree of bone and joint destruction, and whether ulcers and infections are present. Conservative treatment is mainly used in the active phase and surgery in the stable phase. Conclusion The formulation of individualized and stepped treatment regimens can help improve the effectiveness of diabetic CNO of foot and ankle. However, there is still a lack of definitive clinical evidence to guide the treatment of active and stable phases, and further research is needed.
Objective To assess the effectiveness of supramalleolar osteotomy (SMOT) as a therapeutic intervention for varus-type ankle arthritis, while also examining the associated risk factors that may contribute to treatment failure. MethodsThe clinical data of 82 patients (89 feet) diagnosed with varus-type ankle arthritis and treated with SMOT between January 2016 and December 2020 were retrospectively analyzed. The patient cohort consisted of 34 males with 38 feet and 48 females with 51 feet, with the mean age of 54.3 years (range, 43-72 years). The average body mass index was 24.43 kg/m2 (range, 20.43-30.15 kg/m2). The preoperative tibial anterior surface angle (TAS) ranged from 77.6° to 88.4°, with a mean of 84.4°. The modified Takakura stage was used to classify the severity of the condition, with 9 feet in stage Ⅱ, 41 feet in stage Ⅲa, and 39 feet in stage Ⅲb. Clinical functional assessment was conducted using the Maryland sore, visual analogue scale (VAS) score, and psychological and physical scores in Health Survey 12-item Short From (SF-12). Radiology evaluations include TAS, talar tilt (TT), tibiocrural angle (TC), tibial medial malleolars (TMM), tibiocrural distance (TCD), tibial lateral surface angle (TLS), and hindfoot alignment angle (HAA). The results of clinical failure, functional failure, and radiology failure were statistically analyzed, and the related risk factors were analyzed. ResultsThe operation time ranged from 45 to 88 minutes, with an average of 62.2 minutes. No complication such as fractures and neurovascular injuries was found during operation. There were 7 feet of poor healing of the medial incision; 9 pin tract infections occurred in 6 feet using external fixator; there were 20 cases of allograft and 3 cases of autograft with radiographic bone resorption. Except for 1 foot of severe infection treated with bone cement, the remaining 88 feet were primary healing, and the healing area was more than 80%. All patients were followed up 24-82 months, with an average of 50.2 months. Maryland score, VAS score, SF-12 psychological and physiological scores, and TAS, TC, TLS, TCD, TT, TMM, HAA, and Takakura stage were significantly improved at last follow-up (P<0.05). Postoperative clinical failure occurred in 13 feet, functional failure in 15 feet, and radiology failure in 23 feet. Univariate analysis showed that obesity, TT>10°, and Takakura stage Ⅲb were risk factors for clinical failure, HAA≥15° and Takakura stage Ⅲb were risk factors for functional failure, and TT>10° was risk factor for radiographic failure (P<0.05). Further logistic regression analysis showed that TT>10°, HAA≥15°, and TT>10° were risk factors for clinical failure, functional failure, and radiographic failure, respectively (P<0.05). Conclusion SMOT is effective in the mid- and long-term in the treatment of varus-type ankle arthritis, but it should be used with caution in patients with obesity, severe hindfoot varus, severe talus tilt, and preoperative Takakura stage Ⅲb.