Evaluation of hip angles with magnetic resonance imaging in early stage femoral head osteonecrosis

Introduction: It was aimed to compare the patients having clinical and radiological diagnosis of femoroacetabular impingement syndrome with the control group by magnetic resonance imaging, and alpha angle and the central corner angle described by Wiberg.Material and Method: Routine hip MRIs were analyzed retrospectively between January 2016 and May 2019. Clinically and radiologically, patients diagnosed with cam, pincer, and mixed FAI were recorded. A control group matching age and sex was created. The alpha angle was determined as the angle between the line drawn from the center of the femoral neck to the center of the femoral head in axial T1A magnetic resonance imaging, and the line drawn from the center of the femoral head to the point where the femoral head begins to turn towards the neck.Central corner angle of Wiberg’s was measured as the angle between the perpendicular line drawn from the center of the femoral head to the acetabulum on the coronal T1A images and the line connecting the outermost point of the acetabulum. Measurements were compared statistically in both groups. p<0.05 was considered statistically significant.Results: 16 of 28 patients (18 men, 10 women) with FAI had impingement in both hips and a total of 44 hips were examined. There were 9 cam, 23 pincer and 12 mixed impingement cases in the patient group. When FAI and control groups were compared, alpha and Wiberg’s angles were found to be significantly different (p<0.05). In subgroup analysis, there was a significant difference between cam type and control group, mixed type and control group, pincer type and cam type, pincer type and mixed type in terms of alpha angles (p<0.05). For Wiberg’s angles, a significant difference was found between pincer type and control group, mixed type and control group, pincer type and cam type, mixed type and cam type (p<0.05). Cut off values were 54.45 (auc=0.64) for alpha angle and 37.30 (auc=0.83) for Wiberg angle.Conclusion: Alpha angle measurement cam type and Wiberg angle measurement provide useful information for the diagnosis of pincer type impingement with MRI.

BackgroundThe etiology of osteonecrosis of femoral head (ONFH) has not been fully elucidated. Increased intravascular coagulation and/or hypofibrinolysis have been proposed as pathogenic mechanisms. Previous reports demonstrated significant association between incidence of ONFH and polymorphisms of genes related with thrombophilia especially in Caucasian subjects. The aim of our study was to evaluate the relationship between genetic mutations leading to coagulation disorders and ONFH in Polish patients.MethodsWe have investigated the frequencies of four markers among 68 unrelated individuals with clinically and radiographically documented ONFH and among 100 healthy unrelated blood donors in Eastern part of Poland. The three genes were involved in thrombophilia: factor V Leiden (G1691A), prothrombin (G20210A), Methylenetetrahydrofolate Reductase (MTHFR C677T) and one in hypofibrinolysis: Tissue Plasminogen Activator (PLAT TPA25 I/D). The samples were genotyped with polymerase chain reaction followed by restriction enzyme analysis for the restriction fragment length polymorphisms. The allele and genotype frequencies were analyzed in the relation to ONFH etiology (idiopathic and secondary), gender, age (patients younger or older than 50 years) and the number of affected joints (unilateral or bilateral ONFH).ResultsNo significant difference in allele frequencies between patients and control groups were observed in genes involved in thrombophilia. We have found a statistically significant increased frequency of D allele of PLAT TPA 25 I/D polymorphism between the entire group of patients with ONFH and controls (p=0,026, OR=1,54, CI 0,99-2,4). D allele frequency was also significantly increased in patients with primary ONFH (p=0,009, OR=1,81 CI 1,1-3,01), in males (p= 0,013; OR 1,74; 95% CIs 1,08-2,78), patients older than 50 years (p= 0,018, OR= 2,04; 95% CIs 1,09-3,82) and in cases with bilateral ONFH (p= 0,01; OR= 1,92; 95% CIs 1,13-3,27) (Table 9). The differences in DD homozygous genotype frequency were statistically significant for patients with idiopathic ONFH compared with control group (p=0,023, OR=2,75, CI 0,99-7,9) and in cases of bilateral ONFH (p=0,034; OR 3,12; 95% CIs 1,06-9,18) (Table 10). The frequencies of ID heterozygous genotype were statistically significantly higher in entire group of patients with ONFH (p=0,004 OR 2,71; 95% CIs 1,32-5,57), idiopathic ONFH (p= 0,01; OR 2,91; 95% CIs 1,24-6,87), males (p=0,0007; OR 3,75; 95% CIs 1,67-8,42), patients older than 50 years (p=0,001; OR 6,89; 95% CIs 1,87-25,84) and in cases with bilateral ONFH (p=0,009; OR 3,19; 95% CIs 1,26-8,03).ConclusionThe results suggest that inherited hypofibrinolysis is a risk factor of idiopathic ONFH in Polish population.

To explore the changes and its significance of the expression of vascular endothelial growth factor (VEGF) protein and messenger RNA in the Beagle dogs femoral head during the repairing process of the osteonecrosis of femoral head (ONFH) under different stress force stimulations. Twenty-four Beagle dogs were selected to establish the model of ONFH through the method of liquid nitrogen cryopreservation. In the mean time, the necrotic femoral heads stimulated by different stress forces were enrolled into 3 groups: group B (low stress force stimulation group), group C (high stress force stimulation group) and group D (average stress force stimulation group). Group A was control group. The beagle dogs were sacrificed at Weeks 4 and 8 post-operation. The changes of femoral head were evaluated by histological observation, immunohistochemical staining and quantitative reverse transcription-polymerase chain reaction (RT-PCR). Histological observation showed that articular cartilage, morphology and structure of trabecular bone in group D was better than those of groups B and C. Immunohistochemistry revealed that the VEGF protein positive staining in group D was significantly higher than that in groups A, B and C at Weeks 4 and 8 post-operation. The expression of VEGF mRNA in group D was much more than that in groups A, B and C by RT-PCR. And the expression was higher at Week 8 post-operation. Proper stress force stimulation can effectively promote the expression of VEGF protein and messenger RNA in necrotic femoral head of Beagle dogs and boost angiogenesis to improve the blood supply of necrotic femoral head so as to accelerate the repairing process of ONFH.

Objective To investigate the feasibility and clinical efficacy of free graft of vascularized iliac bone flap based on deep iliac circumflex vessels for the treatment of osteonecrosis of femoral head (ONFH). Methods Twelve cases of ONFH (13 hips) received free graft of vascularized iliac bone flap based on deep iliac circumflex vessels from April, 2016 to July, 2017. The average Harris score was (74.7±6.9) in the second stage and (68.6±9.2) in the third stage. After debriding the necrosis bone of the femoral head, the contralateral vascularized iliac bone flap had been harvested, and then implanted into the femoral head. The deep iliac circumflex artery and its accompanying vein were anastomosed with the transverse branch (or ascending branch) of the lateral circumflex femoral artery and concomitant vein respectively. The herringbone brace was used for hip fixation for 3 weeks after operation. X-ray examination(1, 3, 6, 9 and 12 months after operation, respectively) and Harris hip score (6 and 12 months after operation, respectively) were performed to evaluate the recovery results of the femoral head. Scores were recorded and analyzed by paired t-test. The difference was considered to statistically significant if P<0.05. Results The patients were followed-up for 15 (12-20) months. The iliac bone flap of 12 patients (13 hips) healed well. There was no necrosis and collapse in 12 hips, except 1 femoral head collapsed slightly because of weight loading too early. The average Harris score was (91.6±4.5) of the second stage and (84.8±6.1) of the third stage. Compared with scores before the operation, the difference was statistically significant (P<0.05). Conclusion Free vascularized iliac bone grafting based on deep iliac circumflex vessels is an ideal treatment for ONFH head in middle and advanced stage. Key words: Osteonecrosis of the femoral head; Iliac bone flap; Deep iliac circumflex vessels; Transplantation; Harris hip score

Cell therapy has been proposed as part of the therapeutic arsenal to assist bone formation and remodeling in the early stages of osteonecrosis of the femoral head. The purpose of this study is to determine the effects of intraosseous inoculation of mesenchymal stem cells on bone formation and remodeling in an established experimental model of osteonecrosis of the femoral head in immature pigs. Thirty-one 4-week-old immature Yorkshire pigs were used. Experimental osteonecrosis of the femoral head was created in the right hip of all included animals (n = 31). The month after surgery, hip and pelvis radiographs were taken to confirm osteonecrosis of the femoral head. Four animals were excluded following surgery. Two groups were established: (A) mesenchymal stem cell-treated group (n = 13) and (B) saline-treated group (n = 14). One month after surgery the mesenchymal stem cell-group received an intraosseous injection of 10 × 106 mesenchymal stem cell (5 cc) and the saline-treated group of 5 cc of physiological saline solution. Osteonecrosis of the femoral head progression was assessed by monthly X-rays (1-, 2-, 3- and 4-months post-surgery). The animals were sacrificed 1 or 3 months following the intraosseous injection. Repair tissue and osteonecrosis of the femoral head were histologically evaluated immediately after sacrifice. At time of sacrifice, radiographic images showed evident osteonecrosis of the femoral head with associated severe femoral head deformity in 11 of the 14 animals (78%) in the saline group and in only 2 of the 13 animals (15%) in the mesenchymal stem cell group. Histologically, the mesenchymal stem cell group showed less osteonecrosis of the femoral head and less flattening. In the saline group, there was pronounced femoral head flattening and the damaged epiphyseal trabecular bone was largely replaced with fibrovascular tissue. Intraosseous mesenchymal stem cells inoculation improved bone healing and remodeling in our immature pig osteonecrosis of the femoral head model. This work supports further investigation to determine whether mesenchymal stem cells enhance the healing process in immature osteonecrosis of the femoral head.

Alpha and beta angles are commonly used radiographic measures to assess the sphericity of the proximal femur and distance between the pathologic head-neck junction and the acetabular rim, respectively. The aim of this study was to explore the relationship between these two measurements on frog-leg lateral hip radiographs. Fifty frog-leg lateral hip radiographs were evaluated by two orthopaedic surgeons and two radiologists. Each reviewer measured the alpha and beta angles on two separate occasions to determine the relationship between positive alpha and beta angles and the inter- and intra-observer reliability of these measurements. There was no significant association between positive alpha and beta angles, [kappa range -0.043 (95 % CI -0.17 to 0.086) to 0.54 (95 % CI 0.33-0.75)]. Intra-observer reliability was high [alpha angle intra-class correlation coefficient (ICC) range 0.74 (95 % CI 0.58-0.84) to 0.99 (95 % CI 0.98-0.99) and beta angle ICC range 0.86 (95 % CI 0.76-0.92) to 0.97 (95 % CI 0.95-0.98)]. There is no statistical or functional relationship between readings of positive alpha and beta angles. The radiographic measurements resulted in high intra-observer and fair-to-moderate inter-observer reliability. Results of this study suggest that the presence of a CAM lesion on lateral radiographs as suggested by a positive alpha angle does not necessitate a decrease in clearance between the femoral head and acetabular rim as measured by the beta angle and thus may not be the best measure of functional impingement. Understanding the relationship between these two aspects of femoroacetabular impingement improves a surgeon's ability to anticipate potential operative management.

Objective To compare the CT and magnetic resonance imaging (MRI) examination in the application value in the diagnosis and treatment of osteonecrosis of the femoral head. Methods 42 cases of early avascular necrosis of the femoral head were underwent CT and MRI examination, and two kinds of imaging methods were compared. Results MRI diagnosis of avascular necrosis of femoral head in 1 patient detection rate (87.50%) was significantly higher than that of CT (56.25%), and the difference was statistically significant (χ2=3.96, P 0.05). The detection rate of MRI diagnosis for single cystic degeneration (93.75%) and CT (75.00%) had no significant difference (χ2=2.13, P>0.05). MRI in the diagnosis of bone trabecular structure fuzzy detection rate (75.00%) was significantly higher than that of CT (12.50%), and the difference was significant (χ2=12.70, P<0.05). Conclusion In the early diagnosis of osteonecrosis of the femoral head, MRI could detect changes of early avascular necrosis of the femoral head bone marrow edema and fat necrosis sensitively.MRI was superior to CT in accuracy, harmfulness and sensitivity.It could intuitively reflect the shape of lesions and pathological changes.So it could improve the overall level of diagnosis of osteonecrosis of the femoral head. Key words: Tomography, X-ray computed; Magnetic resonance imaging; Osteonecrosis of the femoral head; Diagnosis

To summarize retrospectively the clinical technology of repairing osteonecrosis of femoral head (ONFH) by free vascularized fibular grafting (FVFG), and the value of modified instruments in operation. Between March 2011 and January 2013, 35 patients with ONFH (47 hips) who underwent FVFG with modified instruments. There were 24 males (32 hips) and 11 females (15 hips), aged 34 years on average (range, 22-43 years). The unilateral hip was involved in 23 cases and the bilateral hips in 12 cases. The disease duration ranged from 5 to 9 months (mean, 7 months). Based on etiology, 25 hips were classified as alcohol ONFH, 12 hips as corticosteroids ONFH, 3 hips as trauma ONFH, and 7 hips as idiopathic ONFH. According to the Association Research Circulation Osseous(ARCO) stage, 3 hips were rated as stage I, 39 hips as stage II, and 5 hips as stage III on the X-ray films. The preoperative Harris score was 58.2±6.1. The time to get fibula was 15-35 minutes (mean, 25 minutes). The operation time was 90-200 minutes (mean, 130 minutes), and the blood loss during operation was 150-500 mL (mean, 270 mL). All the patients achieved primary healing of incision, without complication of infection or deep vein thrombosis. All 35 patients were followed up 12-42 months, with an average of 28 months. The Harris score at final follow-up was 87.3±5.7, showing significant difference when compared with preoperative score ( t=102.038, P=0.000). Radiographic results at final follow-up showed good position of fibula; and necrosis was improved in 9 hips, had no changes in 36 hips, and aggravated in 2 hips. FVFG for ONFH can improve hip function effectively, and modified instruments can improve operation efficiency.

Is beta angle the new alpha angle? Reliability and correlation with cartilage health in femoroacetabular impingement syndrome

Urinary miRNAs as biomarkers for idiopathic osteonecrosis of femoral head: A multicentre study

Different repair processes affect the clinical course of nontraumatic avascular femoral head osteonecrosis, not just necrotic lesion size and location. Fourteen femoral heads were retrieved at total hip arthroplasty after core decompression treatment, or after conservative treatment was done on 13 male patients diagnosed with different stages of femoral head osteonecrosis. To determine repair types, features of coronal magnetic resonance images were correlated with light microscopy findings on corresponding coronal undecalcified sections and microradiographs of the retrieved femoral heads. In five femoral heads, repair of necrotic bone and marrow remained restricted to the reactive interface for as many as 63 months, producing the diagnostic osteosclerotic rim with adjacent hypervascularity (limited repair). Nine femoral heads showed extension of the repair process into the necrosis. In five femoral heads, predominant resorption of necrotic bone led to femoral head breakdown within 2 to 50 months (destructive repair). In four femoral heads, reparative bone formation had started from subchondral fractures and/or the reactive interface, definitely reducing the size of the necrotic area (reconstructive repair). In the latter, the disease progressed slowly or stopped for as many as 45 months, irrespective of treatments, but elimination of risk factors seemed beneficial. Although core decompression did not always reach the necrotic area and improve repair, it reduced accompanying bone marrow edema and could delay the disease progress. Osteonecrosis with limited repair can be identified on magnetic resonance images obtained at followup, but the similar signal changes of destructive and reconstructive repair cannot be distinguished on magnetic resonance images alone. The evidence of reconstructive repair in nontraumatic osteonecrosis, however, gives hope for treatments that can improve repair to a sufficient creeping substitution of the affected femoral head.

Application clinique de l’imagerie à une résonance magnétique radiale dans l’analyse de lésions de la coiffe des rotateurs

Clinical application of radial magnetic resonance imaging for evaluation of rotator cuff tear

Aim. Idiopathic aseptic femoral head osteonecrosis is one of the diseases which happen often and in most cases lead to permanent disability.Methods and results. On purpose to establish qualitative-quantitative features and differences between pathomorphological changes and their consequences in comparison groups divided by lesion remoteness, on histotopogfaphic specimens of 30 femoral heads from patients with aseptic osteonecrosis values of parametric and nonparametric indices were investigated.Conclusion. It was found that aseptic femoral head osteonecrosis is large-focal lesion which persist for years and in overwhelming majority of cases does not lead to complete necrosis replacement. Statistically estimated intergroup differences of some morphological indices of femoral head tissue lesion and reparation indicate that pathological changes gradually progress in the direction of coxarthrosis of average or high degree.

To evaluate the efficacies of treating osteonecrosis of the femoral head (ONFH) with percutaneous retaining catheterization. A total of 85 patients (106 hips) of ONFH underwent percutaneous retaining catheterization with self-made instrument. There were stage I (n = 32, 40 hips), stage II (n = 41, 50 hips), stage III (n = 7, 9 hips) and stage IV (n = 5, 7 hips) by Ficat and Arlet classification. The selection criteria include bone marrow edema (BME) of the femoral head and neck and joint fluid on magnetic resonance imaging (MRI).The percent method(%) of Orthopedics Branch of Association of Chinese Medical Association was used for evaluating the efficacies of ONFH with retained femoral head. A follow-up period of 2-10 years was conducted with plain radiograph.The standard was as follows: >90, excellent; 75-89, good; 60-74, passable; <60, bad. The combination of excellent and good denoted obvious effect rate; passable for valid rate; bad for invalid rate.The historical core decompression was used as control group.And χ(2) test was used for statistical analysis (P < 0.05). The obvious effect rate was 88%(35/40), 74%(37/50), 22%(2/9), 14%(1/7), the valid rate 7%(3/40), 12% (6/50) , 22% (2/9), 14%(1/7) and the invalid rate 5%(2/40), 14% (7/50) , 56% (5/9), 72% (5/7) respectively in Ficat I, II, III and IV stage. No statistically significant differences existed between Ficat I and II stage (P > 0.05) .But there were statistically significant differences in other groups (P < 0.01) . Percutaneous retaining catheterization is efficaciously treating ONFH in Ficat I and II stage and it may also be used for ONFH in Ficat III and IV stage.