Objective To investigate the accuracy of the modified Akagi line which referenced the patellar tendon at the attachment and the geometrical center point of the tibial osteotomy surface for tibial rotational alignment. Methods Between July 2021 and December 2021, 72 patients who underwent three-dimension (3D) CT for varus osteoarthritis knees were enrolled. Among 72 patients, 18 were male and 54 were female with a mean age of 64.9 years (range, 47-84 years). The preoperative hip-knee-ankle angle ranged from 0° to 26°, with a mean of 9.3°. CT images were imported into Mimics 21.0 medical image control system to establish 3D models of the knees. The prominent point of lateral epicondyle and the medial epicondylar sulcus were identified in femoral 3D models to construct the surgical transepicondylar axis and the vertical line of its projection [anteroposterior (AP) axis]. In tibial 3D models, the patellar tendon at the attachment was used as anatomical landmarks to construct rotational alignment for tibial component, including the line connecting the medial border of the patellar tendon at the attachment (C) and the middle (O) of the posterior cruciate ligament insertion (Akagi line), the line connecting the point C and the geometric center (GC) of the tibial osteotomy plane [medial border axis of the patellar tendon (MBPT)], the line connecting the medial sixth point of the patellar tendon at the attachment and the point GC [medial sixth axis of the patellar tendon (MSPT)], the line connecting the medial third point of the patellar tendon at the attachment and point O [medial third axis of the patellar tendon 1 (MTPT1)], and the line connecting the medial third point of the patellar tendon at the attachment and point GC [medial third axis of the patellar tendon 2 (MTPT2)]. The angles between the five reference axes and the AP axis were measured, and the distribution of the rotational mismatch angles with the AP axis was counted (≤3°, 3°-5°, 5°-10°, and >10°). Results Relative to the AP axis, the Akagi line and MBPT were internally rotated (1.6±5.9)° and (2.4±6.9)°, respectively, while MSPT, MTPT1, and MTPT2 were externally rotated (5.4±6.6)°, (7.0±5.8)°, and (11.9±6.6)°, respectively. There were significant differences in the rotational mismatch angle and its distribution between reference axes and the AP axis (F=68.937, P<0.001; χ2=248.144, P<0.001). The difference between Akagi line and MBPT showed no significant difference (P=0.067), and the differences between Akagi line and MSPT, MTPT1, MTPT2 were significant (P<0.012 5). ConclusionWhen the position of the posterior cruciate ligament insertion can not be accurately identified on total knee arthroplasty, MBPT can be used as the modified Akagi line in reference to the geometrical center point of the tibial osteotomy surface to construct a reliable rotational alignment of the tibial component.
ObjectiveTo evaluate the effects of the improved precision alignment method of lower limbs mecha-nical alignment for osteoarthritis of the knee in open wedge high tibial osteotomy (OWHTO).MethodsA retrospective analysis was made on the clinical data of 62 patients (68 knees) with knee osteoarthritis in the medial compartment treated with OWHTO between January 2012 and December 2015 who accorded with the inclusion criteria. The traditional method for positioning lower limb mechanical force line was used in 29 cases (32 knees) (traditional group), and improved method for positioning lower limb mechanical force line in 33 cases (36 knees) (modified group). There was no significant difference in gender, age, side, course of disease, and osteoarthritis grading between two groups (P>0.05) with comparable. The operation time, intraoperative fluoroscopy times, and intraoperative blood loss were recorded in two groups; Before and after operation, the lower limb mechanical force line was observed on the X-ray films, which was expressed by hip-knee-ankle angle (HKA). The clinical efficacy was evaluated by the American Hospital for Special Surgery (HSS) score, and the Western Ontario and McMaster University Osteoarthritis Index (WOMAC).ResultsIncision hematoma occurred in 1 case of traditional group and was cured at 3 weeks after symptomatic treatment; and primary healing was obtained in the other patients, with no early complications. The operation time and intraoperative fluoroscopy times of the modified group were significantly lower than those of the traditional group (t=11.934, P=0.000; t=11.663, P=0.000), but there was no significant difference in blood loss between the two groups (t=0.209, P=0.835). The patients were followed up for 6 to 24 months (mean, 12.7 months) in the traditional group and for 3 to 22 months (mean, 13.2 months) in the modified group. The medial knee pain disappeared in all patients. At last follow-up, the HSS score and WOMAC score were significantly improved when compared with preoperative scores in two groups (P<0.05), but there was no significant difference between the two groups (P>0.05). Postoperative X-ray examination showed that the tibiofemoral angle was corrected in the two groups. The HKA angle at immediate after operation and last follow-up was significantly higher than angle at pre-operation in two groups (P<0.05), but there was no significant difference between at immediate after operation and at last follow-up (P>0.05).ConclusionCompared with the traditional method for positioning lower limb mechanical force line, the improved precision alignment method can reduce the times of intraoperative fluoroscopy and shorten the operation time, which reduces the radiation exposure of both doctors and patients.
Objective To explore the prediction of postoperative coronal lower limb alignment by the tibia fibular angle (TFA) and femoral fibular angle (FFA) after osteotomy in medial open-wedge high tibial osteotomy (MOWHTO). Methods A clinical data of 20 patients with medial compartment osteoarthritis, who were treated with MOWHTO between September 2019 and September 2020, was retrospectively analyzed. Among them, there were 9 males and 11 females; the age ranged from 46 to 69 years, with an average of 56.0 years. The body mass index (BMI) was 21.3- 35.7 kg/m2, with an average of 26.7 kg/m2. Osteoarthritis involved 11 cases of left knee and 9 cases of right knee; the disease duration was 2-6 years, with an average of 3.8 years. According to the Kellgren-Lawrence classification, there were 7 cases of grade Ⅰ, 9 cases of grade Ⅱ, and 4 cases of grade Ⅲ. The angle and height for open-wedge was planned preoperatively by osteotomy master software, and the TFA and FFA were measured by software after simulated osteotomy. The intraoperative angle for open-wedge was adjusted according to TFA and FFA after simulated osteotomy.The lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), joint line convergence angle (JLCA), mechanical femorotibial angle (mFTA), weight-bearing line (WBL) ratio, TFA, and FFA were measured before operation and at 2 days after operation. The difference (X) between the intraoperative measurement value and the preoperative plan value of TFA/FFA, and the difference (Y) between the postoperative WBL ratio and the target alignment (62.5%) were calculated, and the correlation between the two indicators was analyzed by Pearson’s test. According to the median BMI of patients (25.81 kg/m2), the patients were allocated into high BMI group (>25.81 kg/m2, n=10) and low BMI group (≤25.81 kg/m2, n=10), and the influencing factors of WBL ratio was analyzed by linear regression. Results There was no significant difference between pre- and post-operation in LDFA and JLCA (P>0.05); while there were significant differences between pre- and post-operation in MPTA, mFTA, and WBL ratio (P<0.05). The TFA was (89.5±4.0)° during operation and (87.7±4.7)° after operation, showing significant difference (t=2.991, P=0.008). There was a positive correlation between the difference (X) between the intraoperative measurement value and the preoperative plan value of TFA and the difference (Y) between the postoperative WBL ratio and the target alignment (r=0.595, P=0.006). The FFA was (86.9±4.3)° during operation and (85.7±4.4)° after operation, showing significant difference (t=1.760, P=0.094). There was a positive correlation between the difference (X) between the intraoperative measurement value and the preoperative plan value of FFA and the difference (Y) between the postoperative WBL ratio and the target alignment (r=0.536, P=0.015). After BMI stratification, X was an influential factor of Y in the low BMI group (P<0.05), but X was not an influential factor of Y in the high BMI group (P>0.05). Conclusion Intraoperative FFA and TFA can predict coronal limb alignment after MOWHTO. FFA and TFA can predict more preciselyfor patients with BMI≤25.81 kg/m2.
Medical cross-modal retrieval aims to achieve semantic similarity search between different modalities of medical cases, such as quickly locating relevant ultrasound images through ultrasound reports, or using ultrasound images to retrieve matching reports. However, existing medical cross-modal hash retrieval methods face significant challenges, including semantic and visual differences between modalities and the scalability issues of hash algorithms in handling large-scale data. To address these challenges, this paper proposes a Medical image Semantic Alignment Cross-modal Hashing based on Transformer (MSACH). The algorithm employed a segmented training strategy, combining modality feature extraction and hash function learning, effectively extracting low-dimensional features containing important semantic information. A Transformer encoder was used for cross-modal semantic learning. By introducing manifold similarity constraints, balance constraints, and a linear classification network constraint, the algorithm enhanced the discriminability of the hash codes. Experimental results demonstrated that the MSACH algorithm improved the mean average precision (MAP) by 11.8% and 12.8% on two datasets compared to traditional methods. The algorithm exhibits outstanding performance in enhancing retrieval accuracy and handling large-scale medical data, showing promising potential for practical applications.
Objective To investigate the rotational mismatch of total kneereplacement with medial 1/3 of tibial tuberosity as bony landmark in osteoarthritic patients with varus or valgus deformity. Methods Axial images on computed tomography of 62 knees (including 55 varus deformities and 7 valgus deformities) in 32 Chinese osteoarthritic patients who had total knee arthroplasty were analyzed, compared with that of 10 healthy knees. On images of the distal femur, the angle between the lines of surgical epicondylar axis(SEA) and posterior condylar axis was measured as posterior condylar angle (PCA), and on images of the proximal tibia, a baseline for the anteriorposterior axis of each component was drawn based on the SEA for the femur and the medial 1/3 of the tibial tuberosity for the tibia. The angle between these lines (Angle α) was defined as therotational mismatch between the components when they were aligned to the anatomic landmarks of each bone. Results The sulcus of medial epicondyle of femur could be identified on CT images of over 80% osteoarthritic knees; the median value of PCA was +2.36°, with an individual variation of 0° to +7.5°. Angle α was +6.45±3.68°(range, 0° to +11.8°) in 10 healthy knees, which increased significantly to +10.85±10.47°(range, 0° to +28.1°)in 55 varus knees (P＜0.05), which also increased significantly to +11.6±7.3°(range, -6.5° to +26.8°) in 7 valgus knees (P＜ 0.05). Conclusion With the medial 1/3 of the tibial tuberosity as the rotational landmark for the tibial component, there was a tendency to align the tibial component in external rotational position relative to the femoral component in knees with normal alignment, the rotational mismatch increased in Chinese osteoarthritic knees with varus and valgus deformity.
ObjectiveTo investigate the effect of three-dimensional (3D) printing guide plate on improving femoral rotational alignment and patellar tracking in total knee arthroplasty (TKA).MethodsBetween January 2018 and October 2018, 60 patients (60 knees) with advanced knee osteoarthritis who received TKA and met the selection criteria were selected as the study subjects. Patients were randomly divided into two groups according to the random number table method, with 30 patients in each group. The TKA was done with the help of 3D printing guide plate in the guide group and following traditional procedure in the control group. There was no significant difference in gender, age, disease duration, side, and preoperative hip-knee-ankle angle (HKA), posterior condylar angle (PCA), patella transverse axis-femoral transepicondylar axis angle (PFA), Hospital for Special Surgery (HSS) score, and American Knee Society (AKS) score (P>0.05).ResultsAll incisions healed by first intention and no complications related to the operation occurred. All patients were followed up 10-12 months, with an average of 11 months. HSS score and AKS score of the two groups at 6 months after operation were significantly higher than those before operation (P<0.05), but there was no significant difference between the two groups (P>0.05). Postoperative X-ray films showed that the prosthesis was in good position, and no prosthesis loosening or sinking occurred during follow-up. HKA, PCA, and PFA significantly improved in the two groups at 10 months after operation compared with those before operation (P<0.05). There was no significant difference in HKA at 10 months between the two groups (t=1.031, P=0.307). PCA and PFA in the guide group were smaller than those in the control group (P<0.05).ConclusionApplication of 3D printing guide plate in TKA can not only correct the deformity of the knee joint and alleviate the pain symptoms, but also achieve the goal of the accurate femoral rotation alignment and good patellar tracking.
ObjectiveTo investigate the effect of preoperative valgus or varus deformity on the prosthesis installation and alignment restoration in total knee arthroplasty (TKA). MethodsBetween January 2012 and December 2013, 198 patients (245 knees) with osteoarthritis underwent primary TKA, and the clinical data were retrospectively analyzed. There were 23 males and 175 females, with the average age of 67 years (range, 43-90 years). Single knee and double knees were involved in 151 and 47 cases respectively. The disease duration was from 1 month to 30 years (mean, 8.99 years). The anteroposterior X-ray films of whole lower limbs were taken, and the femorotibial angle (FT) was measured before operation and at 1 week after operation; the mechanical femoral angle (MF) and the anatomical tibial angle (AT) at 1 week after operation were measured. The correlation analysis was made for pre-and post-operative FT, MF, and AT. According to the valgus or varus deformity before operation, all patients were divided into 5 groups:≥20° varus (group A), 10-20° varus (group B), ≤10° varus (group C), < 10° valgus (group D), and≥10° valgus (group E), and the above indicators were compared between groups. And the rate of the good limb alignment was recorded after operation. ResultsThe pre-and post-operative FT were (171.53±9.12) and (177.38±3.57)° respectively, and postoperative MF and AT were (89.00±2.68) and (88.62±2.16)° respectively. Preoperative FT was associated with postoperative FT and MF (r=0.375, P=0.000; r=0.386, P=0.000), but it was not correlated with AT (r=0.024, P=0.710). Postoperative FT was associated with MF and AT (r=0.707, P=0.000; r=0.582, P=0.000). Postoperative FT was significantly increased when compared with preoperative FT in each group (P < 0.05). There were significant differences in preoperative FT between groups (P < 0.05). There were significant differences in postoperative FT when compared group A with groups B, C, D, and E (P < 0.05), and when compared groups B and C with groups D and E (P < 0.05), but there was no significant difference between groups B and C, and between groups D and E (P>0.05). The rate of good alignment was 70.2% (172/245); it was 27.8% (5/18), 66.0% (62/94), 74.4% (67/90), 88.9% (32/36), and 85.7% (6/7) in groups A, B, C, D, and E respectively, showing significant differences between groups (P < 0.05). There was no significant difference in postoperative AT between groups (P>0.05). Except for between group D and group E (P>0.05), significant difference in MF was shown between the other groups (P < 0.05). ConclusionThe more severe deformity of lower limb before TKA, the higher risk of deviation for prosthesis installation and poor alignment in TKA.
Commissural misalignment of biological valve and autologous valve during transcatheter aortic valve replacement may affect the filling of coronary artery, reduce the feasibility of redo-aortic valve intervention and damage the valve function, which will adversely affect long-term prognosis of patients. Some studies have obtained achievement by changing the axial direction of valve and using individualized computer simulation technology to improve the alignment technology. However, there are still many unknown problems about the impact of commissural misalignment on patients, and accurate commissural alignment techniques still need to be further explored. This article systematically expounds the possible impact of commissural misalignment between biological valve and autologous valve in transcatheter aortic valve replacement, possibly effective accurate commissural alignment techniques and related research progress.
Objective To evaluate the early effectiveness of navigation-free robot-assisted total knee arthroplasty (TKA) compared to traditional TKA in the treatment of knee osteoarthritis combined with extra-articular deformities. Methods The clinical data of 30 patients with knee osteoarthritis combined with extra-articular deformities who met the selection criteria between June 2019 and January 2024 were retrospectively analyzed. Fifteen patients underwent CORI navigation-free robot-assisted TKA and intra-articular osteotomy (robot group) and 15 patients underwent traditional TKA and intra-articular osteotomy (traditional group). There was no significant difference in age, gender, body mass index, affected knee side, extra-articular deformity angle, deformity position, deformity type, and preoperative knee range of motion, American Knee Society (KSS) knee score and KSS function score, and lower limb alignment deviation between the two groups (P>0.05). The operation time, intraoperative blood loss, and complications of the two groups were recorded and compared. The knee range of motion and lower limb alignment deviation were recorded before operation and at 6 months after operation, and the knee joint function was evaluated by KSS knee score and function score. Results There was no significant difference in operation time between the two groups (P>0.05); the intraoperative blood loss in the robot group was significantly less than that in the traditional group (P<0.05). Patients in both groups were followed up 6-12 months, with an average of 8.7 months. The incisions of all patients healed well, and there was no postoperative complication such as thrombosis or infection. At 6 months after operation, X-ray examination showed that the position of the prosthesis was good in both groups, and there was no loosening or dislocation of the prosthesis. The knee joint range of motion, the lower limb alignment deviation, and the KSS knee score and KSS function score significantly improved in both groups (P<0.05) compared to preoperative ones. The changes of lower limb alignment deviation and KSS function score between pre- and post-operation in the robot group were significantly better than those in the traditional group (P<0.05), while the changes of other indicators between pre- and post-operation in the two groups were not significant (P>0.05). Conclusion Compared to traditional TKA, navigation-free robot-assisted TKA for knee osteoarthritis with extra-articular deformities results in less intraoperative blood loss, more precise reconstruction of lower limb alignment, and better early effectiveness. However, long-term effectiveness require further investigation.
ObjectiveTo summarize the methods of tibial prosthesis rotation alignment in total knee arthroplasty, and provide reference for clinicians to select and further study the methods of tibial prosthesis rotation alignment.MethodsThe advantages and disadvantages of various tibial prosthesis rotation alignment methods were analyzed and summarized by referring to the relevant literature at home and abroad in recent years.ResultsThere are many methods for tibial prosthesis rotation alignment, including reference to relevant anatomical landmarks, range of motion (ROM) technique, computer-assisted navigation, and personalized osteotomy. The inner one-third of the tibial tuberosity is a more accurate reference anatomical landmark, but the obesity, severe knee deformity and dysplasia have impacts on the precise placement of the tibial prosthesis. ROM technique do not need to refer to the anatomical landmark of the tibia, and aren’t affected by landmark variation. It can be used for severe knee valgus deformity and the landmarks that are difficult to identify. However, it may cause internal rotation of tibial prosthesis. Computer- assisted navigation and personalized osteotomy can achieve more accurate alignment in sagittal, coronal, and rotational alignment of femoral prosthesis. However, due to the lack of reliable anatomical landmarkers related to tibia fixation, it is still controversial whether it can help the alignment of tibial prosthesis rotation.ConclusionThe surgeon should master the methods of rotation and alignment of tibial prosthesis, make preoperative plans, select appropriate alignment methods for different patients, and achieve individualization. Meanwhile, several anatomical landmarkers should be referred to properly during the operation, which can be used to detect the correct placement of tibial prosthesis and avoid large rotation error.