OBJECTIVE: To explore correlation between imaging classification of knee osteoarthritis (KOA) and axis angle of tibiofemoral and patellofemoral joints. METHODS: A retrospective analysis of 739 middle-aged and elderly patients with KOA (1 026 knee joints) who underwent vertical X-ray examination of both lower limbs and lateral knee joints from September 2018 to December 2020. Among them, 63 patients with K-L 0 grade (95 knee joints), 100 patients with K-L 1 grade (130 knee joints), 161 patients with K-L 2 grade (226 knee joints), 187 patients with K-L 3 grade (256 knee joints), and 228 patients of K-L 4 grade (319 knee joints). According to relative position of knee joint center and line between hip joint center and ankle joint center, the affected knee was divided into varus group(844 knees joints) and valgus group (182 knees joints). According to Install-Salvati method, the affected knee was divided into three groups, such as high patella (patella height>1.2 mm, 347 knees joints), median patella (patella height ranged from 0.8 to 1.2 mm, 561 knees joints), and low patella (patella height<0.8 mm, 118 knees joints). Lower femur angle, upper tibia angle, femoral neck shaft angle, femoral tibial angle, joint gap angle, hip-knee-ankle angle, patella-femoral angle and patella height among different groups were observed and compared. RESULTS: (1) In varus KOA group, there were statistical differnces in hip-knee-ankle angle, tibiofemoral angle, lower femoral angle, upper tibial angle, joint space angle, and femoral neck shaft angle of patients with different K-L grades (P<0.05). Hip-knee-ankle angle, tibiofemoral angle, lower femoral angle, upper tibial angle, joint space angle and K-L grade were significantly positively correlated at 0.01(P<0.05);femoral neck shaft angle and K-L grade showed negative correlation at 0.01(P<0.05). (2) In valgus KOA group, hip-knee-ankle angle, there were statistical differences in tibiofemoral angle, inferior femoral angle, superior tibial angle, joint space angle, and femoral neck shaft angle of patients with different K-L grades(P<0.05). Hip-knee-ankle angle, tibiofemoral angle, lower femoral angle, upper tibial angle, and femoral neck shaft angle showed negative correlation with K-L grades at level of 0.01 (P<0.05);joint gap angle and K-L grades showed significantly positive correlation at level of 0.01(P<0.05). (3) In high patella group, there were statistically differences in patellar height and patellar femoral angle of different K-L grades(P<0.05);there were no statistical difference in patella height and patellar femoral angle of different K-L grades in median patella group. There was no significant difference in patella heightin low patella group with different K-L grades(P>0.05), and there was statistical difference in patellofemoral angle(P<0.05). Patellar height and patella-femoral angle of high patella group were significantly positively correlated with K-L grades at the level of 0.01 (P<0.05);patella height and patella-femoral angle were not correlated with K-L grades in median patella group(P>0.05). There was no correlation between height of patella and K-L grade in low patella group (P>0.05). There was significant negative correlation between patella-femoral angle and K-L grade at level of 0.05 (P<0.05). CONCLUSION Inferior femoral angle, tibiofemoral angle, joint gap angle, hip-knee-ankle angle, femoral neck shaft angle and high patella are related to K-L classification of varus KOA, which could be used for early diagnosis and provide objective data for efficacy analysis of conservative treatment.
Aged ; Middle Aged ; Humans ; Patellofemoral Joint/diagnostic imaging* ; Osteoarthritis, Knee/diagnostic imaging* ; Retrospective Studies ; Knee Joint ; Femur/diagnostic imaging* ; Tibia

OBJECTIVE: To explore the related factors of femoral stem anteversion (FSA) after total hip arthroplasty (THA), so as to provide reference for clinical design of FSA before operation and reduce the risk of hip dislocation after arthroplasty. METHODS: Ninty-three patients (103 hips) who underwent THA between October 2021 and September 2022 and met the selection criteria were selected as the study subjects. Among them, there were 48 males and 45 females with an average age of 58.5 years (range, 25-88 years). Body mass index was 18.00-37.84 kg/m ², with an average of 24.92 kg/m ². There were 51 cases (57 hips) of osteonecrosis of femoral head, 35 cases (39 hips) of hip osteoarthritis, and 7 cases (7 hips) of congenital hip dysplasia. Based on CT images, the following indicators were measured: preoperative femoral neck anteversion (FNA), preoperative femoral rotation angle (FRA), preoperative acetabular anteversion (AA), and preoperative combined anteversion (CA; the sum of preoperative FNA and AA); postoperative FSA and the change in femoral anteversion angle (the difference between postoperative FSA and preoperative FNA). Based on preoperative X-ray films, the following indicators were measured: femoral cortical thickness index (CTI) and canal flare index (CFI), the proximal femoral medullary cavity was classified according to Noble classification (champagne cup type, normal type, chimney type), neck-shaft angle (NSA), and femoral offset (FO). Pearson correlation analysis, one-way ANOVA, and Point-biserial correlation analysis were used to investigate the correlation between postoperative FSA, postoperative change in femoral anteversion angle, and patient diagnosis, proximal femoral medullary cavity anatomy type, gender, age, as well as preoperative FNA, FRA, AA, CA, NSA, FO, CTI, and CFI. FSA was used as the dependent variable and the independent variables that may be related to it were included for multiple linear regression analysis. RESULTS: Based on CT image measurement, preoperative FNA was (15.96±10.01)°, FRA (3.36±10.87)°, AA (12.94±8.83)°, CA (28.9±12.6)°, postoperative FSA (16.18±11.01)°, and postoperative change in femoral anteversion angle was (0.22±9.98)°. Based on preoperative X-ray films measurements, the CTI was 0.586±0.081; the CFI was 4.135±1.125, with 23 hips classified as champagne cup type, 68 hips as normal type, and 12 hips as chimney type in the proximal femoral medullary cavity anatomy; NSA was (132.87±7.83)°; FO was (40.53±10.11) mm. There was no significant difference between preoperative FNA and postoperative FSA ( t=-0.227, P=0.821). Pearson correlation analysis showed that postoperative FSA was positively correlated with preoperative FNA, preoperative CA, postoperative change in femoral anteversion angle, and age ( P<0.05), while negatively correlated with preoperative FRA ( P<0.05). The postoperative change in femoral anteversion angle were positively correlated with preoperative FRA and postoperative FSA ( P<0.05), and negatively correlated with preoperative CA and FNA ( P<0.05). One-way ANOVA analysis showed that the above two indicators were not correlated with diagnosis and the proximal femoral medullary cavity anatomy type ( P>0.05). Multiple linear regression analysis showed a linear correlation between FSA and FNA, CA, age, and FRA ( F=10.998, P<0.001), and the best fit model was FSA=0.48×FNA-2.551. CONCLUSION The factors related to FSA after THA include patient's age, preoperative FNA, CA, FRA and postoperative femoral anteversion, of which preoperative FNA is the most closely related. When designing a surgical plan before surgery, attention should be paid to the patient's preoperative FNA, and if necessary, CT around the hip joint should be scanned to gain a detailed understanding of the proximal femoral anatomical structure.
Female ; Male ; Humans ; Middle Aged ; Arthroplasty, Replacement, Hip ; Femur/diagnostic imaging* ; Femur Neck ; Femur Head ; Hip Joint

OBJECTIVE: To establish finite element models of different preserved angles of osteonecrosis of the femoral head (ONFH) for the biomechanical analysis, and to provide mechanical evidence for predicting the risk of ONFH collapse with anterior preserved angle (APA) and lateral preserved angle (LPA). METHODS: A healthy adult was selected as the study object, and the CT data of the left femoral head was acquired and imported into Mimics 21.0 software to reconstruct a complete proximal femur model and construct 3 models of necrotic area with equal volume and different morphology, all models were imported into Solidworks 2022 software to construct 21 finite element models of ONFH with LPA of 45°, 50°, 55°, 60°, 65°, 70°, and 75° when APA was 45°, respectively, and 21 finite element models of ONFH with APA of 45°, 50°, 55°, 60°, 65°, 70°, 75° when LPA was 45°, respectively. According to the physiological load condition of the femoral head, the distal femur was completely fixed, and a force with an angle of 25°, downward direction, and a magnitude of 3.5 times the subject's body mass was applied to the weight-bearing area of the femoral head surface. The maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head were calculated and observed by Abaqus 2021 software. RESULTS: The finite element models of ONFH were basically consistent with biomechanics of ONFH. Under the same loading condition, there was stress concentration around the necrotic area in the 42 ONFH models with different preserved angles composed of 3 necrotic areas with equal volume and different morphology. When APA was 60°, the maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head of the ONFH models with LPA<60° were significantly higher than those of the models with LPA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with LPA≥60° ( P>0.05). When LPA was 60°, each index of the ONFH models with APA<60° were significantly higher than those of the models with APA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with APA≥60° ( P>0.05). CONCLUSION From the perspective of biomechanics, when a preserved angle of ONFH is less than its critical value, the stress concentration phenomenon in the femoral head is more pronounced, suggesting that the necrotic femoral head may have a higher risk of collapse in this state.
Adult ; Humans ; Femur Head/surgery* ; Finite Element Analysis ; Stress, Mechanical ; Femur/diagnostic imaging* ; Femur Head Necrosis/surgery*

OBJECTIVE: To explore 3.0T MRI accurate measurement of knee cartilage thickness in healthy youth provides reliable anatomical parameters for quantitative diagnosis of osteoarthritis and accurate osteotomy of joint replacement. METHODS: From January 2013 to December 2013, 30 healthy young volunteers including 14 males and 16 females with an average age of (25.8±2.4) years old ranging from 22 to 33 years were recruited in Changchun, Jilin Province, and a 3.0T MRI scan was performed on the bilateral knee joints of each volunteer. The cartilage thickness was measured on the lateral femoral condyle (LFC), medial femoral condyle (MFC), lateral tibial plateau (LTP) and medial tibial plateau (MTP). RESULTS: In four regions of the knee joint:LFC, MFC, LTP and MTP, whether young men or women, there was no significant difference in cartilage thickness between the left and right knee joints (P>0.05). There were significant differences in knee cartilage thickness between healthy young men and women (P<0.05). In the same sex group, LFC cartilage thickness was thinner in the middle, thicker in front and rear;MFC cartilage thickness was the thinnest in front and gradually thickening from the front to the rear; LTP cartilage thickness was thickest in the middle, second in the rear and thinnest in the front;MTP cartilage thickness was the thinnest in the front, was relatively uniform in the middle and rear and thicker than that in the front. CONCLUSION In Northeast China, among healthy adults aged 22 to 33, gender difference may be an important factor in the difference of cartilage thickness in various regions of the knee joint. Regardless of whether male or female healthy young people, the cartilage thickness of the entire knee joint is unevenly distributed, but there is no significant difference in cartilage thickness in the same area between the left and right knee joints.
Adult ; Adolescent ; Humans ; Male ; Female ; Young Adult ; Cartilage, Articular/diagnostic imaging* ; Knee Joint/surgery* ; Osteoarthritis ; Magnetic Resonance Imaging ; Femur

OBJECTIVE: To analysis and determine MR signs of Harris score ARCO stages 2-4 in osteonecrosis of femoral head (ONFH). METHODS: Thirty-four patients with ONFH of ARCO stages 2 to 4 who underwent routine MR, T2 mapping, 3D-SPACE sequence examination and Harris score were retrospectively collected from January 2019 to June 2020, and 3 patients were excluded, and 31 patients were finally included, including 23 males and 8 females, aged from 18 to 62 years old with an average of(40.0±10.8) years old. Among them 21 patients with bilateral femoral head necrosis, totally 52 cases, including 17 with ARCO stage 2 patients, 24 ARCO stage 3, and 11 ARCO stage 4. MR imaging signs (femoral head collapse depth, ONFH index, bone marrow edema, hyperplasia, grade and T2 value of cartilage injury, and joint effusion) were scored and measured on the picture archiving and communication system (PACS) workstation, and the cartilage quantitative parameter T2 value was calculated and measured on Siemens postprocessing workstation. Pearson correlation analysis was used to evaluate the correlation between various MR signs and Harris score, and then multiple linear regression analysis was used to examine impact of MR signs on Harris hip score. RESULTS: Femoral head collapse depth(r=-0.563, P=0.000), grade of cartilage injury(r=-0.500, P=0.000), and joint effusion (r=-0.535, P=0.000) were negatively correlated with Harris score by Pearson correlation analysis. Multiple linear regression analysis showed that joint effusion(β=-6.198, P=0.001) and femoral head collapse depth(β=-4.085, P=0.014) had a significant negative impact on Harris hip score. CONCLUSION Femoral head collapse depth and joint effusion both had significant negative relationship with Harris hip score. It is recommended to routinely evaluate femoral head collapse depth and joint effusion quantitatively and gradedly, so as to efficiently and accurately assist clinical diagnosis and treatment.
Male ; Female ; Humans ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Femur Head Necrosis/diagnostic imaging* ; Retrospective Studies ; Femur Head/diagnostic imaging* ; Bone Transplantation/methods* ; Magnetic Resonance Imaging ; Treatment Outcome

OBJECTIVE: To investigate the relationship between the area of psoas major muscle(PMI) and recurrent contralateral hip fracture in the initial intertrochanteric fracture. METHODS: Total of 87 patients with intertrochanteric fracture of femur from January 2008 to January 2011 were selected for CT scanning of lumbar spine and hip at the time of the first fracture, and then divided into two groups according to whether there was fracture in the contralateral hip, 13 patients in the contralateral hip fracture group, 5 males and 8 females, aged(82.30±5.66) years;there were 74 cases in the non contralateral hip fracture group, including 32 males and 42 females, with an age of (79.70±5.84) years. The gender, age, preoperative blood albumin value, operation side, body mass index(BMI), Harris score of hip joint one year after operation, Barthel index before operation and medical diseases before operation were observed and compared between two groups. The PMI was used to compare the area of psosa major on CT before operation in two groups, and the correlation between the area of PMI at the time of initial fracture and the fracture of the contralateral hip was evaluated. RESULTS: The two groups were followed up for more than 2 years after operation. There was a significant difference in PMI between two groups(P<0.05). There was a significant positive correlation between preoperative PMI and the time of re fracture of the contralateral hip(r=0.641, P=0.018). CONCLUSION There are differences in the area of PMI in patients with contralateral hip fracture, so the area of PMI can be regarded as an important risk factor for contralateral hip fracture.
Male ; Female ; Humans ; Psoas Muscles/diagnostic imaging* ; Treatment Outcome ; Hip Fractures/surgery* ; Hip Joint ; Femur

Disability Evaluation ; Femur/diagnostic imaging* ; Humans ; Lower Extremity

OBJECTIVE: To establish a risk assessment and prediction system for early osteonecrosis of the femoral head (ONFH) in order to predict the collapse risk. METHODS: The risk assessment system for early necrosis and collapse of femoral head was established based on the combination of Steinberg stage, ABC typing and the proportion of the proximal sclerotic rim. Firstly, Steinberg stage system was applied. ABC typing was applied to predict risk in stage I, type C was risk free, type B was low risk, type A and type BC were medium risk, type A-C and type AB were high risk. The classification of proximal sclerotic rim was first applied when the Steinberg stage was Ⅱ-Ⅲ, and type 2 was expected to be low risk. If the classification of proximal sclerotic rimwas type 1, then the ABC typing was applied, type C was risk-free, type B was low risk, type A and type BC were medium risk, type A-C and type AB were high risk. According to this prediction system, the collapse risk of femoral head in 188 cases(301 hips) were predicted by retrospective analysis. All the hips were enrolled at the out-patient department of orthopedic in Guang'anmen Hospital attached to China Academy of Chinese Medical Science. The consistency of the prediction results of three doctors and one doctor at different times were evaluated. RESULTS: Among them, 136 cases were male, 52 were female. 75 cases were single hip, 113 were double hip. The age of the patients wa 19 to 64(42.61±12.07) years. The natural course of disease was 0.33 to 5.00(3.62±1.93) years. 206 hips in 301 hips had collapsed, with a collapse rate of 68.44%. In the risk-free group, none hip had collapsed, with a collapse rate of 0%. In the low-risk group, 9 hip in 91 hips had collapsed, with a collapse rate of 9.89%. In the medium-risk group, 12 hip in 19 hips had collapsed, with a collapse rate of 63.16%. And in the high risk group, 185 hips in 190 hips had collapsed, with a collapse rate of 97.37%. They were significantly differences in their collapse rate ( CONCLUSION The risk assessment and prediction system for early ONFH selects different methods to predict the risk of collapse according to the imaging characteristics of different stages, which is combines with the comprehensive assessment of multiple risk factors. The system is applicable to a wide range, simple operation and convenient for clinical application.
Adult ; China ; Female ; Femur Head/diagnostic imaging* ; Femur Head Necrosis/epidemiology* ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Risk Assessment ; Treatment Outcome ; Young Adult

OBJECTIVE: To compare computer measurement semi automatic quantitative detection software system with ultra thin layer pathological section to confirm the avascular necrosis percentage of the femoral head, and provide reference for clinical treatment options. METHODS: From June 2012 to December 2013, the X-ray and MRI of 24 patients(24 hips on unilateral) were reviewed, who had avascular necrosis of the femoral head at late stage (stage III and IV) according to the ARCO international staging system, and performed by total hip arthroplasty. There were 15 males and 9 females, with an average age of (65.1±8.8) years old ranging 33 to 74 years old. Based on imaging system combined with computer aided technology(CAD) system and postoperative ultrathin slice, the volume of the area of femoral head necrosis were calculated. Then combining with the total volume of the femoral head was calculated by X-ray, the percentage of each femoral head necrosis area was calculated as a percentage of the whole ball head in both methods. RESULTS: For 24 hips, the normal femoral head volume was (39.58±3.29) cm³ on average of X-ray film, the necrotic volume was (20.00±3.04) cm³ on average of MRI by the calculation of computer. The necrotic volume occupying in the volume of the normal femoral head was (42.92±6.09)% on average ranged. The necrotic lesion size was larger than 40% in 16 hips, 30% to 40% in 8 hips, 1 ess than 30% in 0 hip. Under the pathological section, the necrosis volume was (19.89±3.17) cm³, the necrotic volume occupying in the volume of the normal femoral head was (40.33±6.36)%. The necrotic lesion size was larger than 40% in 12 hips, 30% to 40% in 11 hips, 1 ess than 30% in 1 hip. In computer and general measurement, the two entire femoral head volume difference was (0.113±0.466) cm³, there was no significant difference using these measurements(=-1.186, =0.248). After the linear correlation statistics analysis, there was a positive correlation relationship in necrotic volume between computer software and pathology measurement(γ=0.980, =0.000). CONCLUSIONS The severity of the necrotic femoral head is closely related to the percentage of necrotic area. When the ratio of necrotic lesions and the whole femoral head is greater than 30%, the patients' clinical symptoms tend to aggravate, the probability of total hip arthroplasty increased significantly. It have great significances in femoral head necrosis installment, judge the prognosis, guide the selection of treatment and monitoring curative effect.
Adult ; Aged ; Arthroplasty, Replacement, Hip ; Female ; Femur ; Femur Head ; Femur Head Necrosis ; diagnostic imaging ; Follow-Up Studies ; Hip ; Humans ; Male ; Middle Aged

BACKGROUND: Areal bone mineral density (aBMD) applied for osteoporosis diagnosis unavoidably results in the missingdiagnosis in patients with large bones and misdiagnosis in those with small bones. Therefore, we try to find a new adjusted index of bone mineral content (BMC) to make up shortcomings of aBMD in osteoporosis diagnosis. METHODS: In this multi-center epidemiological study, BMC and aBMD of lumbar spines (n = 5510) and proximal femurs (n = 4710) were measured with dual energy X-ray absorptiometry (DXA). We analyzed the correlation between the bone mass and body weight in all subjects including four age groups (<19 years, 20-39 years, 40-49 years, >50 years). And then the body weight was used for standardizing BMC (named wBMC) and applied for the epidemiological analysis of osteoporosis. RESULTS: The correlation of body weight and BMC is 0.839 to 0.931 of lumbar vertebra 1-4 (L1-4), and 0.71 to 0.95 of femoral neck in different age groups. When aBMD was applied for diagnosing osteoporosis, the prevalence was 7.55%, 16.39%, and 25.83% in patients with a high, intermediate, and low body weight respectively. However, the prevalence was 21.8%, 18.03%, and 11.64% by wBMC applied for diagnosing osteoporosis. Moreover, the prevalence of osteoporosis increased by 3.76% by wBMC with the body weight increased by 5 kg. The prevalence decreased by 1.94% when the body weight decreased by 5 kg. CONCLUSIONS wBMC can reduce the missed diagnosis in patients with large body weight and reduce misdiagnosis in those with small body weight. Including children, wBMC may be feasible for osteoporosis diagnosis individuals at any age.
Absorptiometry, Photon ; Adult ; Age Factors ; Body Weight ; physiology ; Bone Density ; physiology ; Female ; Femur Neck ; diagnostic imaging ; metabolism ; Humans ; Lumbar Vertebrae ; diagnostic imaging ; metabolism ; Middle Aged ; Osteoporosis ; diagnostic imaging ; metabolism ; Prevalence ; Young Adult