OBJECTIVE: To summarize the research progress on the role of macrophage-mediated osteoimmune in osteonecrosis of the femoral head (ONFH) and its mechanisms. METHODS: Recent studies on the role and mechanism of macrophage-mediated osteoimmune in ONFH at home and abroad were extensively reviewed. The classification and function of macrophages were summarized, the osteoimmune regulation of macrophages on chronic inflammation in ONFH was summarized, and the pathophysiological mechanism of osteonecrosis was expounded from the perspective of osteoimmune, which provided new ideas for the treatment of ONFH. RESULTS: Macrophages are important immune cells involved in inflammatory response, which can differentiate into classically activated type (M1) and alternatively activated type (M2), and play specific functions to participate in and regulate the physiological and pathological processes of the body. Studies have shown that bone immune imbalance mediated by macrophages can cause local chronic inflammation and lead to the occurrence and development of ONFH. Therefore, regulating macrophage polarization is a potential ONFH treatment strategy. In chronic inflammatory microenvironment, inhibiting macrophage polarization to M1 can promote local inflammatory dissipation and effectively delay the progression of ONFH; regulating macrophage polarization to M2 can build a local osteoimmune microenvironment conducive to bone repair, which is helpful to necrotic tissue regeneration and repair to a certain extent. CONCLUSION At present, it has been confirmed that macrophage-mediated chronic inflammatory immune microenvironment is an important mechanism for the occurrence and development of ONFH. It is necessary to study the subtypes of immune cells in ONFH, the interaction between immune cells and macrophages, and the interaction between various immune cells and macrophages, which is beneficial to the development of potential therapeutic methods for ONFH.
Humans ; Femur Head/pathology* ; Osteonecrosis/therapy* ; Macrophages/pathology* ; Inflammation ; Femur Head Necrosis/pathology*

OBJECTIVE: To analyze the clinical effect of decompression and bone grafting on osteonecrosis of the femoral head(ONFH) at different sites of necrotic lesions. METHODS: A total of 105 patients with ARCOⅡstage ONFH admitted from January 2017 to December 2018 were retrospectively analyzed. There were 71 males and 34 females, with an average age of (55.20±10.98) years old. The mean course of all patients was(15.91±9.85) months. According to Japanese Inveatigation Committee (JIC) classification, all patients were divided into 4 types:17 cases of type A, 26 cases of type B, 33 cases of type C1 and 29 cases of type C2. All four groups were treated with decompression of the pulp core and bone grafting. Visual analogue scale(VAS) and Harris hip joint score were used before and at 3, 6, 12, and 24 months after the operation, and the collapse of the femoral head was observed by X-ray examination within 2 years. RESULTS: All 105 patients were successful on operation without complications, and the mean follow-up duration was (24.45±2.75) months. Harris score showed that there was no statistical difference among four groups before surgery and 3, 6 months after surgery (P>0.05);at 12 and 24 months after surgery, there were significant differences among all groups (P<0.01). There were significant differences in intragroup Harris scores at preoperative and postoperative time points among four groups (P<0.01). VAS showed that there was no statistical difference among four groups before and 3, 6 months after surgery (P>0.05);at 12 and 24 months after surgery, there were significant differences among all groups (P<0.01). There were significant differences in VAS at preoperative and postoperative time points among four groups (P<0.01). None of the patients in four groups had femoral head collapse before and 3, 6 months after surgery. At 12 months after operation, there were 3 cases of femoral head collapse in group C and 4 cases in group C2(P>0.05);At 24 months after operation, 1 case of femoral head collapse occurred in group B, 6 cases in group C1 and 8 cases in group C2(P<0.05). CONCLUSION Core decompression and bone grafting can improve the effect of ONFH and hip preservation. The effect of hip preservation for ONFH is closely related to the location of the osteonecrosis lesion, so the influence of the location of lesion on the effect of hip preservation should be considered in clinical treatment, so as to make better preoperative hip preservation plan.
Male ; Female ; Humans ; Adult ; Middle Aged ; Aged ; Retrospective Studies ; Femur Head Necrosis/diagnosis* ; Femur Head/surgery* ; Treatment Outcome ; Decompression, Surgical ; Bone Transplantation

The stability of internal fixation of femoral neck fractures can be obtained through surgical techniques, the configuration of screws and bone grafting, etc. However, the blood supply injury caused by fractures could not be completely reversed by the current medical management. Hence, the comprehensive evaluation of the residual blood supply of the femoral neck, to perioperatively avoid further iatrogenic injury, has become a hotspot. The anatomy of the extraosseous blood supply of the femoral neck has been widely reported, while its clinical application mostly involved the assessment of the medial circumflex femoral artery and retinacular arteries. However, further studies are needed to explore the prognosis of patients with these artery injuries, with different degrees, caused by femoral neck fractures. Direct observations of nutrient foramina in vivo are not possible with current clinical technologies, but it is possible to make reasonable preoperative planning to avoid subsequent femoral head necrosis based on the distribution features of nutrient foramina. The anatomy and clinical application studies of the intraosseous blood supply focused on the junction area of the femoral head and neck to probe the mechanism of femoral head necrosis. Thus, the intraosseous blood supply of other regions in the femoral neck remains to be further investigated. In addition, a blood supply evaluation system based on a three-level structure, extraosseous blood vessels, nutrient foramina, and intraosseous vascular network, could be explored to assist in the treatment of femoral neck fractures.
Humans ; Femur Head Necrosis ; Femoral Neck Fractures/surgery* ; Femur Neck ; Femur Head/surgery* ; Femoral Artery ; Fracture Fixation, Internal

OBJECTIVE: To analyze the femoral head collapse and the operation of osteonecrosis of the femoral head (ONFH) in different Japanese Investigation Commitee (JIC) types, in order to summarize the prognostic rules of each type of ONFH, and explore the clinical significance of CT lateral subtypes based on reconstruction of necrotic area of C1 type and verify their clinical effect. METHODS: A total of 119 patients (155 hips) with ONFH between May 2004 and December 2016 were enrolled in the study. The total hips consisted of 34 hips in type A, 33 in type B, 57 in type C1, and 31 in type C2, respectively. There was no significant difference in age, gender, affected side, or type of ONFH of the patients with differenct JIC types ( P>0.05). The 1-, 2-, and 5-year femoral head collapse and operation of different JIC types were analyzed, as well as the survival rate (with femoral head collapse as the end point) of hip joint between different JIC types, hormonal/non-hormonal ONFH, asymptomatic and symptomatic (pain duration >6 months or ≤6 months), and combined preserved angle (CPA) ≥118.725° and CPA<118.725°. JIC types with significant differences in subgroup surgery and collapse and with research value were selected. According to the location of the necrotic area on the surface of the femoral head, the JIC classification was divided into 5 subtypes in the lateral CT reconstruction, and the contour line of the necrotic area was extracted and matched to the standard femoral head model, and the necrosis of the five subtypes was presented by thermography. The 1-, 2-, and 5-year outcomes of femoral head collapse and operation in different lateral subtypes were analyzed, and the survival rates (with collapse of the femoral head as the end point) between CPA≥118.725° and CPA<118.725° hip in patients with this subtype were compared, as well as the survival rates of different lateral subtypes (with collapse and surgery as the end points, respectively). RESULTS: The femoral head collapse rate and operation rate in the 1-, 2-, and 5-year were significantly higher in patients with JIC C2 type than in patients with other hip types ( P<0.05), while in patients with JIC C1 type than in patients with JIC types A and B ( P<0.05). The survival rate of patients with different JIC types was significantly different ( P<0.05), and the survival rate of patients with JIC types A, B, C1, and C2 decreased gradually. The survival rate of asymptomatic hip was significantly higher than that of symptomatic hip, and the survival rate of CPA≥118.725° was significantly higher than that of CPA<118.725° ( P<0.05). The lateral CT reconstruction of type C1 hip necrosis area was selected for further classification, including type 1 in 12 hips, type 2 in 20 hips, type 3 in 9 hips, type 4 in 9 hips, and type 5 in 7 hips. There were significant differences in the femoral head collapse rate and the operation rate among the subtypes after 5 years of follow-up ( P<0.05). The collapse rate and operation rate of types 4 and 5 were 0; the collapse rate and operation rate of type 3 were the highest; the collapse rate of type 2 was high, but the operation rate was lower than that of type 3; the collapse rate of type 1 was high, but the operation rate was 0. In JIC type C1 patients, the survival rate of the hip joint with CPA≥118.725° was significantly higher than that with CPA<118.725° ( P<0.05). In the follow-up with femoral head collapse as the end point, the survival rates of types 4 and 5 were all 100%, while the survival rates of types 1, 2, and 3 were all 0, and the difference was significant ( P<0.05). The survival rate of types 1, 4, and 5 was 100%, of type 3 was 0, and of type 2 was 60%, showing significant difference ( P<0.05). CONCLUSION JIC types A and B can be treated by non-surgical treatment, while type C2 can be treated by surgical treatment with hip preservation. Type C1 was classified into 5 subtypes by CT lateral classification, type 3 has the highest risk of femoral head collapse, types 4 and 5 have low risk of femoral head collapse and operation, type 1 has high femoral head collapse rate but low risk of operation; type 2 has high collapse rate, but the operation rate is close to the average of JIC type C1, which still needs to be further studied.
Humans ; Femur Head/surgery* ; Femur Head Necrosis/surgery* ; Retrospective Studies ; Hip Joint ; Tomography, X-Ray Computed

OBJECTIVE: To describe the disease characteristics of osteonecrosis of the femoral head (ONFH) in patients with systemic lupus erythematosus (SLE) who experiencing prolonged glucocorticoid (GC) exposure. METHODS: Between January 2016 and June 2019, 449 SLE patients meeting the criteria were recruited from multiple centers. Hip MRI examinations were performed during screening and regular follow-up to determine the occurrence of ONFH. The cohort was divided into ONFH and non-ONFH groups, and the differences in demographic baseline characteristics, general clinical characteristics, GC medication information, combined medication, and hip clinical features were compared and comprehensively described. RESULTS: The age at SLE diagnosis was 29.8 (23.2, 40.9) years, with 93.1% (418 cases) being female. The duration of GC exposure was 5.3 (2.0, 10.5) years, and the cumulative incidence of SLE-ONFH was 9.1%. Significant differences ( P<0.05) between ONFH and non-ONFH groups were observed in the following clinical characteristics: ① Demographic baseline characteristics: ONFH group had a higher proportion of patients with body mass index (BMI)<20 kg/m ² compared to non-ONFH group. ② General clinical characteristics: ONFH group showed a higher proportion of patients with cutaneous and renal manifestations, positive antiphospholipid antibodies (aPLs) and anticardiolipin antibodies, severe SLE patients [baseline SLE Disease Activity Index 2000 (SLEDAI-2K) score ≥15], and secondary hypertension. Fasting blood glucose in ONFH group was also higher. ③ GC medication information: ONFH group had higher initial intravenous GC exposure rates, duration, cumulative doses, higher cumulative GC doses in the first month and the first 3 months, higher average daily doses in the first 3 months, and higher proportions of average daily doses ≥15.0 mg/d and ≥30.0 mg/d, as well as higher full-course average daily doses and proportion of full-course daily doses ≥30.0 mg/d compared to non-ONFH group. ④ Combined medications: ONFH group had a significantly higher rate of antiplatelet drug use than non-ONFH group. ⑤ Hip clinical features: ONFH group had a higher proportion of hip discomfort or pain and a higher incidence of hip joint effusion before MRI screening than non-ONFH group. CONCLUSION The incidence of ONFH after GC exposure in China's SLE population remains high (9.1%), with short-term (first 3 months), medium-to-high dose (average daily dose ≥15 mg/d) GC being closely associated with ONFH. Severe SLE, low BMI, certain clinical phenotypes, positive aPLs, and secondary hypertension may also be related to ONFH.
Female ; Male ; Humans ; Glucocorticoids/adverse effects* ; Incidence ; Femur Head ; Prospective Studies ; Femur Head Necrosis/epidemiology* ; Lupus Erythematosus, Systemic/chemically induced* ; Hypertension/drug therapy*

For the treatment of an intertrochanteric fracture combined with femoral head necrosis in middle-age patients, it has been controversial whether to perform fracture reduction and fixation first then total hip replacement, or direct total hip replacement. We present a rare case of 53-year-old male patient suffered from bilateral intertrochanteric fracture caused by a road traffic injury. The patient had a history of femoral head necrosis for eight years, and the Harris score was 30. We performed total hip replacement with prolonged biologic shank prostheses for primary repair. One year after the surgery, nearly full range of motion was achieved without instability (active flexion angle of 110°, extension angle of 20°, adduction angle of 40°, abduction angle of 40°, internal rotation angle of 25°, and external rotation angle of 40°). The Harris score was 85. For the middle-aged patient with unstable intertrochanteric fractures and osteonecrosis of the femoral head, we can choose primary repair for concurrent bilateral intertrochanteric fracture and femoral head necrosis with prolonged shank biologic total hip replacement.
Male ; Middle Aged ; Humans ; Arthroplasty, Replacement, Hip/methods* ; Femur Head/surgery* ; Femur Head Necrosis/surgery* ; Fracture Fixation, Internal/methods* ; Hip Fractures/surgery* ; Biological Products ; Treatment Outcome ; Retrospective Studies

Humans ; Aged ; Femoral Neck Fractures/surgery* ; Fracture Fixation, Internal/adverse effects* ; Osteonecrosis/surgery* ; Femur Head Necrosis/surgery*

The approach combining disease, syndrome, and symptom was employed to investigate the characteristic changes of blood stasis syndrome in a rat model of steroid-induced osteonecrosis of the femoral head(SONFH) during disease onset and progression. Seventy-two male SD rats were randomized into a healthy control group and a model group. The rat model of SONFH was established by injection of lipopolysaccharide(LPS) in the tail vein at a dose of 20 μg·kg~(-1)·d~(-1) on days 1 and 2 and gluteal intramuscular injection of methylprednisolone sodium succinate(MPS) at a dose of 40 mg·kg~(-1)·d~(-1) on days 3-5, while the healthy control group received an equal volume of saline. The mechanical pain test, tongue color RGB technique, gait detection, open field test, and inclined plane test were employed to assess hip pain, tongue color, limping, joint activity, and lower limb strength, respectively, at different time points within 21 weeks of modeling. At weeks 2, 4, 8, 12, 16, and 21 after modeling, histopathological changes of the femoral head were observed by hematoxylin-eosin(HE) staining and micro-CT scanning; four coagulation items were measured by rotational thromboelastometry; and enzyme-linked immunosorbent assay(ELISA) was employed to determine the levels of six blood lipids, vascular endothelial growth factor(VEGF), endothelin-1(ET-1), nitric oxide(NO), tissue-type plasminogen activator(t-PA), plasminogen activator inhibitor factor-1(PAI-1), bone gla protein(BGP), alkaline phosphatase(ALP), receptor activator of nuclear factor-κB(RANKL), osteoprotegerin(OPG), and tartrate-resistant acid phosphatase 5b(TRAP5b) in the serum, as well as the levels of 6-keto-prostaglandin 1α(6-keto-PGF1α) and thromboxane B2(TXB2) in the plasma. The results demonstrated that the pathological alterations in the SONFH rats were severer over time. The bone trabecular area ratio, adipocyte number, empty lacuna rate, bone mineral density(BMD), bone volume/tissue volume(BV/TV), trabecular thickness(Tb.Th), trabecular number(Tb.N), bone surface area/bone volume(BS/BV), and trabecular separation(Tb.Sp) all significantly increased or decreased over the modeling time after week 4. Compared with the healthy control group, the mechanical pain threshold, gait swing speed, stride, standing time, and walking cycle of SONFH rats changed significantly within 21 weeks after modeling, with the greatest difference observed 12 weeks after modeling. The time spent in the central zone, rearing score, and maximum tilt angle in the open field test of SONFH rats also changed significantly over the modeling time. Compared with the healthy control group, the R, G, and B values of the tongue color of the model rats decreased significantly, with the greatest difference observed 11 weeks after modeling. The levels of total cholesterol(TC), total triglycerides(TG), low-density lipoprotein-cholesterol(LDL-C), and apoprotein B(ApoB) in the SONFH rats changed significantly 4 and 8 weeks after modeling. The levels of VEGF, ET-1, NO, t-PA, PAI-1, 6-keto-PGF1α, TXB2, four coagulation items, and TXB2/6-keto-PGF1α ratio in the serum of SONFH rats changed significantly 4-16 weeks after modeling, with the greatest differences observed 12 weeks after modeling. The levels of BGP, TRAP5b, RANKL, OPG, and RANKL/OPG ratio in the serum of SONFH rats changed significantly 8-21 weeks after modeling. During the entire onset and progression of SONFH in rats, the blood stasis syndrome characteristics such as hyperalgesia, tongue color darkening, gait abnormalities, platelet, vascular, and coagulation dysfunctions were observed, which gradually worsened and then gradually alleviated in the disease course(2-21 weeks), with the most notable differences occurred around 12 weeks after modeling.
Rats ; Male ; Animals ; Femur Head/pathology* ; Plasminogen Activator Inhibitor 1/adverse effects* ; Vascular Endothelial Growth Factor A ; Femur Head Necrosis/pathology* ; Rats, Sprague-Dawley ; Steroids ; Pain ; Cholesterol

OBJECTIVE: To explore effectiveness of positive support reduction and internal fixation in the treatment of femoral neck fractures. METHODS: A clinical data of 74 patients with femoral neck fractures treated with hollow screw internal fixation between September 2017 and September 2021 was retrospectively analyzed. Based on the quality of fracture reduction, they were divided into positive support reduction group (group A, n=25), negative support reduction group (group B, n=21), and anatomical reduction group (group C, n=28). There was no significant difference in baseline data such as gender, age, cause of injury, disease duration, fracture side, Garden classification, and fracture line position classification between groups (P>0.05). The occurrence of complications such as early fixation failure, femoral neck shortening, non-union of fractures, and femoral head necrosis in three groups, as well as the Harris score of the hip joint were recorded and compared. RESULTS: All patients had primary healing of incisions after operation and were followed up more than 12 months. The follow-up time for groups A, B, and C was (21.1±5.7), (22.6±4.3), and (21.9±4.1) months, respectively; there was no significant difference between groups (P>0.05). There was no significant difference in the incidences of non-union of fractures, early internal fixation failure, and the femoral head necrosis between groups (P>0.05). The incidence and length of femoral neck shortening, and the hip Harris score at last follow-up in groups A and C were all superior to those in the group B, with significant difference (P<0.05). There was no significant difference in the above indicators between groups A and C (P>0.05). CONCLUSION Positive support reduction can provide a good biomechanical environment for the healing of femoral neck fractures, thereby achieving a higher fracture healing rate, reducing the occurrence of femoral neck shortening, minimizing the function of hip joint, and achieving effectiveness similar to anatomical reduction.
Humans ; Femur Head Necrosis ; Retrospective Studies ; Femoral Neck Fractures/surgery* ; Femur Neck ; Plastic Surgery Procedures

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*