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 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 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: Early stage osteonecrosis of the femoral head (ONFH) has many treatment options including core decompression with implantation of a tantalum rod. The purpose of this study was to evaluate clinical and radiological outcomes and potential complications during conversion total hip arthroplasty (THA) in such patients. METHODS: Six male patients (8 hips) underwent THA subsequent to removing a tantalum rod (group I) from April 2010 to November 2011. We retrospectively reviewed the medical records of these patients. We enrolled 12 age- and sex-matched patients (16 hips) during the same period, who had undergone primary THA without a previous operation as the control group (group II). All patients were followed for at least 3 years. We checked the Harris hip score (HHS), operative time, and volume of blood loss. Radiological results, including inclination, anteversion of the acetabular cup, presence of periprosthetic osteolysis, and subsidence of femoral stem were checked at the last follow-up. RESULTS: The mean preoperative HHS values were 56.5 (range, 50 to 62) and 59.1 (range, 42 to 70) in groups I and II, respectively. The HHS improved to 96.0 (range, 93 to 100) and 97.6 (range, 93 to 100), respectively, at the 3-year follow-up (p = 0.172). Mean operation time was 98.8 minutes (range, 70 to 120 minutes) in group I and 77.5 minutes (range, 60 to 115 minutes) in group II (p = 0.006). Total blood loss volumes were 1,193.8 mL (range, 960 to 1,360 mL) and 944.1 mL (range, 640 to 1,280 mL) in groups I and II, respectively (p = 0.004). No significant differences in inclination or anteversion of acetabular cup and no evidence of osteolysis or subsidence of the femoral stem were reported in either group in radiological follow-up results. However, one case of squeaking occurred in group I during the follow-up. CONCLUSIONS: The two groups showed no clinical or radiological differences except extended operative time and increased blood loss. However, the incidence of squeaking (1 of 8 hips) was higher, as compared to the control group or previously reported values.
Adult ; *Arthroplasty, Replacement, Hip/adverse effects/methods/statistics & numerical data ; Case-Control Studies ; *Decompression, Surgical/adverse effects/methods/statistics & numerical data ; Femur Head/diagnostic imaging/surgery ; Femur Head Necrosis/diagnostic imaging/*surgery ; Humans ; Male ; Postoperative Complications ; Reoperation ; Retrospective Studies ; Tantalum/*therapeutic use ; Tomography, X-Ray Computed ; Treatment Outcome

OBJECTIVETo explore the preventive effect of Yougui drink on femoral head necrosis in rats under micro CT.

METHODSTwenty-five SD rats were divided into steroid hormone group (group A, 10 rats ), Yougui drink group (group B,10 rats) and normal group (group C,5 rats)with random number table. Endotoxin were injected into abdominal cavity of rats in group A and B for 2 days, methylprednisolone sodium succinate were injected by gluteus for twice a week continued for 6 weeks; group B were gavaged by Yougui drink (veryday for 8 weeks; group C did not do any processing. All rats were killed on the 10th weeks,m icro CT were used to scan femoral head in vitro and preventive effect of Yougui drink (n femoral head necrosis in rats.

RESULTSThere was statistical significance in BMD, BV/TV, Tb.N, Tb, Th, Thb, Sp, BS/TV and DA but no significance in SMI between group A and B. Comparison between A and C, there was significant meaning in BMD, BV/TV, Tb.N, Tb, Th, Tb, Sp, BS/TV, DA and SMI.

CONCLUSIONYougui drink on femoral head necrosis in rats under micro CT has preventive effect from BMD BV/TV, Tb.N, Tb, Th, Tb, Sp, BS/TV and DA.

Animals ; Apoptosis ; Bone Density ; Drugs, Chinese Herbal ; therapeutic use ; Femur Head Necrosis ; diagnostic imaging ; pathology ; prevention & control ; Rats ; Rats, Sprague-Dawley ; X-Ray Microtomography ; methods

BACKGROUNDOsteonecrosis of the femoral head (ONFH) is the result of dysfunctional blood supply, but associations between specific damaged arteries, imaging changes and clinical sign require more understanding. We investigated characteristics of ONFH that pertain to blood supply, imaging appearance, and clinical feature to judge the prognosis of ONFH.

METHODSClinical data were collected for 92 patients (118 hips) with ONFH, including gender, age, duration of pain (from initial clinical presentation to arthroplasty), cause, stage, and classification. Magmatic resonance imaging and X-rays were obtained of all patients to diagnose ONFH. The sizes of lesions were classified by necrotic index. The location of necrosis was classified as Type A, B, or C using the grading system by magmatic resonance imaging and X-rays. All hips were imaged with digital subtraction angiography to visualize their blood-supply characteristics. Hips were divided into groups based on the source artery for femoral head damage: superior retinacular artery (S), inferior retinacular artery (I), and combined superior and inferior retinacular arteries (S+I). Via digital subtraction angiography, imaging appearances and clinical data in three groups were compared.

RESULTSONFH was caused by damage in either the superior or inferior retinacular artery, or both, in all of 118 hips. The group with only inferior retinacular artery damage reported longer hip pain duration than the other groups. The probability of the lesion extending laterally to the acetabular edge in group S was much more than it in group I. Necrosis indices of the patients in S and S+I were higher than those in group I.

CONCLUSIONSONFH associated with interruption of the superior and inferior retinacular arteries in this study. When the former alone was damaged, the necrosis of the volume was larger, the risk of femoral head collapse was higher and the time from initial clinical presentation to arthroplasty was shorter.

Adult ; Aged ; Angiography, Digital Subtraction ; Female ; Femur Head ; diagnostic imaging ; Femur Head Necrosis ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Young Adult

OBJECTIVETo study the cause of X-ray misdiagnosis of the avascular femur head necrosis, so as to reduce the misdiagnosis rate and raise the early diagnosis level.

METHODSThe clinical and X-ray data of 99 patients(123 hips) with avascular femur head necrosis diagnosed by MRI were analyzed retrospectively. Among the patients, 56 patients were male and 43 patients were female,ranging in age from 21 to 84 years old,with an average of 53 years old. The patients had symptoms such as hip pain,functional restriction in flexion, adduction, abduction and internal rotation,and some patients had limping. The duration of the disease ranged from 1 week to 2 years.

RESULTSAmong 99 patients(123 hips),46 patients(52 hips) was misdiagnosed by the X-ray, the misdiagnosis rate was 42.27%, 100.00% in 0 stage, 100.00% in I stage, 83.67% in II stage, 18.18% in II stage, 0.00% in IV stage, 0.00% in V stage; the X-ray stage was negatively correlated with the rate of misdiagnosis. The careless film-reading and invigorating large enterprises while relaxing control over small ones was the main reason of misdiagnosis,then the lack of clinical histories and low-quality of X-ray projection.

CONCLUSIONThe relevant clinical history and comprehensive careful film-reading is the key to reduce the rate of misdiagnosis.

Adult ; Aged ; Aged, 80 and over ; Diagnostic Errors ; Female ; Femur Head Necrosis ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Radiography ; X-Rays

This paper is aimed to acquire high Geometric similar Subject-specific three-dimensional (3D) finite element mesh model of hip joint containing necrotic femoral head according to individual patient's X-ray, CT and MRI by using the image registration and fusion technology. We selected a middle-aged female patient with osteonecrosis of femoral head, obtained the X-ray, CT and MRI images respectively. Then we established 3D solid model separately based on these image data by using Mimics 13. 1 and Pro/E 5.1 software. We confirmed the match points and then proceed the 2D image registration after image projection conversion. Finally we showed the 3D finite element mesh model. A highly geometric similar subject-specific 3D finite element mesh model for osteonecrosis of femoral head has been established, which included normal cortical bone, cancellous bone, articular cartilage and necrotic zone, fractured trabecular bone within the femoral head. The model truly reflects the morphological characteristics and relationship of hip joint with osteonecrosis of femoral head, provides a relatively ideal research platform for further biomechanical analysis and surgical simulation.
Female ; Femur Head Necrosis ; diagnostic imaging ; pathology ; Finite Element Analysis ; Humans ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; Magnetic Resonance Imaging ; Middle Aged ; Models, Anatomic ; Tomography, X-Ray Computed

OBJECTIVETo investigate the effect of continous perfusion with Danshen and heparin for treatment of femoral head necrosis.

METHODSFrom April 2004 to June 2007,42 patients of femoral head necrosis were treated by contious perfusing with Dandshen and heparin, included 24 males and 18 females with an average age of 39.2 years ranging from 13 to 61 years. There were 18 patients on stage II, 13 patients on stage III, 11 patients on stage IV according to Ficat standard. The venous duct were inserted into femoral head then perfused Danshen and heparin into femoral head for 15 days. Every patient was carried out opacification before treatment and 1 month after operation. Every patient was evaluated according to Harris standard before treatment and 3, 6, 12 months after treatment.

RESULTSAll patients were followed-up for 32 to 68 months (means 42.7 months). The average scores of 18 patients on stage II on 3, 6, 12 months after treatment were (88.43 +/- 3.41), (94.37 +/- 3.47), (92.84 +/-4.29), respectively, and the scores after treatment were higher than the score (78.23 +/- 3.47) after treatment. The average scores of 13 cases on stage III on 3, 6, 12 after treatment were (82.94 +/- 3.31), (88.60 +/- 2.31), (86.09 +/- 3.17) respectivly, and the scores after treatment were higher than the score (66.11 +/- 4.50) before treatment. The average scores of 11 cases on stage IV on 3, 6, 12 months after treatment were (61.31 +/- 4.06), (59.2 +/- 7.31), (54.62 +/- 8.20) respectivly,and the scores on 3, 6 months after treatment were higher than the score (50.16 +/- 2.35) before treatment,but there was no obvious difference between before treatment and 12 months after treatment. The rank of phlebography of 18 cases on stage II and 13 cases on stage IlI were improved obvi ously 1 month after treatment,but there was no obvious difference in 11 cases of stage IV.

CONCLUSIONThe method of contious perfusing with Danshen and heparin into femoral head has the advantage of little damage and good effect. It refers to patients in early stage (II and II ).

Adolescent ; Adult ; Drugs, Chinese Herbal ; administration & dosage ; therapeutic use ; Female ; Femur Head Necrosis ; diagnostic imaging ; drug therapy ; therapy ; Follow-Up Studies ; Heparin ; administration & dosage ; therapeutic use ; Humans ; Male ; Middle Aged ; Perfusion ; methods ; Phlebography ; Treatment Outcome ; Young Adult