OBJECTIVE: To evaluate precise assessment methods for predicting the optimal acetabular cup size in total hip arthroplasty (THA). METHODS: A clinical data of 73 patients (80 hips) who underwent primary THA between December 2022 and July 2024 and met the inclusion criteria was analyzed. There were 39 males and 34 females with an average age of 66.3 years (range, 56-78 years). Among them, 66 cases were unilateral THA and 7 were bilateral THAs. There were 29 patients (34 hips) of osteoarthritis, 35 patients (35 hips) of femoral neck fractures, and 9 patients (11 hips) of osteonecrosis of the femoral head. Based on anteroposterior pelvic X-ray films, three methods were employed to predict acetabular cup size, including preoperative template planning, radiographic femoral head diameter (FHD) measurement, and intraoperative FHD measurement. The predicted acetabular cup sizes from these methods were compared with the actual implanted sizes. RESULTS: The predicted acetabular cup sizes using the preoperative template planning, radiographic FHD measurement, and intraoperative FHD measurement were (51.25±2.81), (49.72±3.11), and (49.90±2.74) mm, respectively, compared to the actual implanted cup size of (50.57±2.74) mm, with no significant difference ( P>0.05). Regarding agreement with the actual implanted cup size, the preoperative template planning achieved exact matches in 35 hips (43.75%), one-size deviation in 41 hips (51.25%), and two-size deviations in 4 hips (5%); the radiographic FHD measurement achieved exact matches in 12 hips (15%), one-size deviation in 57 hips (71.25%), and two-size deviations in 11 hips (13.75%); and the intraoperative FHD measurement achieved exact matches in 26 hips (32.5%), one-size deviation in 52 hips (65%), and two-size deviations in 2 hips (2.5%). There were significant differences in agreement distributions between the three methods and the actual implanted cup sizes ( H=18.579, P<0.001). CONCLUSION The intraoperative FHD measurement, as a simple, cost-effective, and accurate method, effectively guides acetabular cup selection, reduces the risk of prosthesis wear, enhances postoperative joint stability.
Humans ; Arthroplasty, Replacement, Hip/instrumentation* ; Male ; Female ; Middle Aged ; Acetabulum/diagnostic imaging* ; Aged ; Hip Prosthesis ; Prosthesis Design ; Femur Head/surgery* ; Osteoarthritis, Hip/surgery* ; Radiography ; Femoral Neck Fractures/surgery* ; Femur Head Necrosis/surgery*

OBJECTIVE: To investigate whether adding 1 transverse screw (TS) to the triangular parallel cannulated screw (TPCS) fixation has a mechanical stability advantage for Pauwels type Ⅲ femoral neck fractures by conducting finite element analysis on four internal fixation methods. METHODS: Based on CT data of a healthy adult male volunteer's femur, three Pauwels type Ⅲ femoral neck fracture models (Pauwels angle 70°, Pauwels angle 80°, and Pauwels angle 70° combined with bone defect) were constructed using Mimics 21.0 software and SolidWorks 2017 software. Four different internal fixation models were built at the same time, including TPCS, TPCS+TS, three cross screws (TCS), and TPCS+medial buttress plate (MBP). The mechanical stability of different models under the same load was compared by finite element analysis. RESULTS: The femoral model established in this study exhibited a maximum stress of 28.62 MPa, with relatively higher stress concentrated in the femoral neck. These findings were comparable to previous studies, indicating that the constructed femoral finite element model was correct. The maximum stress of internal fixation in finite element analysis showed that TCS was the lowest and TPCS+MBP was the highest in Pauwels angle 70° and 80° models, while TPCS+TS was the lowest and TCS was the highest in Pauwels angle 70° combined with bone defect model. The maximum displacement of internal fixation in each fracture model was located at the top of the femoral head, with TCS having the highest maximum displacement of the femur. The maximum stress of fracture surface in finite element analysis showed that TCS was the lowest and TPCS was the highest in the Pauwels angle 70° model, while TPCS+MBP was the lowest and TPCS/TCS were the highest in the Pauwels angle 80° model and the Pauwels angle 70° combined with bone defect model, respectively. The maximum displacement of fracture surfece analysis showed that TPCS+MBP was the lowest and TCS was the highest in Pauwels angle 70° and 80° models, while TPCS+TS was the lowest and TCS was the highest in Pauwels angle 70° combined with bone defect model. CONCLUSION For Pauwels type Ⅲ femoral neck fractures, the biomechanical stability of TPCS+TS was superior to that of TPCS alone and TCS, but it has not yet reached the level of TPCS+MBP.
Finite Element Analysis ; Humans ; Femoral Neck Fractures/diagnostic imaging* ; Bone Screws ; Fracture Fixation, Internal/instrumentation* ; Male ; Bone Plates ; Stress, Mechanical ; Biomechanical Phenomena ; Tomography, X-Ray Computed ; Adult ; Femur Neck/surgery*

OBJECTIVES: To analyze bone mass distribution and the factors affecting bone mass in a general Chinese Han cohort undergoing physical examinations at our center. METHODS: We retrospectively collected the data of bone mineral density (BMD) measurements from 30 599 healthy Han Chinese adults (age≥20 years) who underwent dual-energy X-ray absorptiometry scans at our hospital from July, 2013 to July, 2023. Basic parameters including height, body weight, and gender were recorded, and descriptive statistics and correlation analyses were performed using R software. RESULTS: In this cohort, the male individuals had a mean peak BMD of 1.00±0.12 g/cm² in the lumbar vertebrae, 0.94±0.14 g/cm² in the femoral neck, and 0.99±0.13 g/cm² in the total hip, significantly higher than the values in the female individuals [0.99±0.12 g/cm² in the lumbar vertebrae (P=0.022), 0.79±0.11 g/cm² in the femoral neck (P<0.001), and 0.88±0.11 g/cm² in the total hip (P<0.001)]. In the overall cohort, the BMD values of the lumbar spine and femur decreased with age after reaching their peak levels. There was a positive correlation between BMD value and body mass index (BMI) in both male and female individuals. The 2013-2014 period recorded the lowest BMD values in the lumbar, hip, and femoral neck, which tended to increase steadily in the following years (2015-2023). CONCLUSIONS Our data suggest that the BMD values vary among different populations, and future multi-center studies using more accurate BMD detection technology are warranted to capture the variation patterns of BMD with demographic characteristics of specific populations.
Humans ; Bone Density ; Absorptiometry, Photon ; Male ; Female ; Retrospective Studies ; Osteoporosis/diagnostic imaging* ; Adult ; Middle Aged ; Lumbar Vertebrae/diagnostic imaging* ; China/epidemiology* ; Femur Neck/diagnostic imaging* ; Aged ; Beijing/epidemiology* ; Young Adult

OBJECTIVE: To explore the effect of femoral neck cortical fragments and surfacial area on avascular necrosis(AVN) after internal fixation of femoral neck fractures based on CT imaging in young adult. METHODS: From January 2011 to January 2021, 218 young and middle-aged patients with femoral neck fractures were reverse triangle fixed with three cannulated lag screws, including 104 males and 114 females;aged 19 to 60 years old with a mean of (48.22±10.58) years old. The preoperative waiting time≤48 h was 155 cases, and the preoperative waiting time> 48 h was 63 cases; 68 cases were comminuted cortex of the femoral neck, 32 of them with superficial area of the comminuted cortex>25 mm². All patients were followed up for at least 2 years, the age, gender, injury side, body mass index, injury mechanism, preoperative waiting time, operation time, Garden classification, whether femoral neck cortex fracture and size by CT analysis and complications were analyzed the correlation to the definite occurrence of AVN. The AVN group and the non-AVN group were divided according to the final efficacy results.Univariate analysis yielded significant independent variables, Multiple Logistic regression analysis was further performed to identify the independent risk factors for AVN. RESULTS: By univariate analysis, the AVN and non-AVN groups were significant in injury mechanism(χ²=18.552, P=0.000), preoperative waiting time( χ²=2.065, P=0.033), Garden classification (χ²=12.598, P=0.006), comminuted cortex (χ²=16.357, P=0.000), and the superficial area of the comminuted cortex(χ²=23.371, 0.000, P=0.000). Multiple Logistic regression indicated injury mechanism high energy injury[Exp(B)=3.487, 95%CI(1.583, 10.464), P=0.002], comminuted cortex of the femoral neck[Exp(B)=2.494, 95%CI(1.315, 10.861), P=0.002];the superficial area of the comminuted cortex>25 mm²[Exp(B)=22.161, 95%CI(3.922, 1242.828), P=0.001] were independent risk factors for AVN after internal fixation of femoral neck fractures. CONCLUSION High energy injury mechanism, with comminuted cortex of the femoral neck and the superficial area of the comminuted cortex> 25 mm² were independent risk factors for AVN.The larger the superficial area of the cortex fragment may suggest more complicated injury mechanism and worse outcome.
Humans ; Male ; Female ; Adult ; Femoral Neck Fractures/diagnostic imaging* ; Tomography, X-Ray Computed ; Middle Aged ; Femur Head Necrosis/etiology* ; Young Adult ; Fracture Fixation, Internal/methods*

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

OBJECTIVE: To retrospectively analyze efficacy of single structure internal fixation and double structure internal fixation in the treatment of ipsilateral femoral shaft and neck fracture, and analyze their indications. METHODS: From June 2015 to December 2020, 21 patients with ipsilateral femoral shaft and femoral neck fracture were treated, including 14 males and 7 females, aged 23 to 69 years old with an average of(38.1±12.9) years old. According to different femoral shaft fracture sites, some patients were fixed with cephalomedullary implant for both femoral neck and the femoral shaft(single structure, InterTan or PFNA Ⅱ), some patients were fixed with cannulated screws for the femoral neck and a retrograde locking nail for the femoral shaft (dual structure), and postoperative function and complications were recorded during follow-up. In 10 cases of single-structure fixation, the femoral necks were all basicervical fractures, and the femoral shaft fractures were located in the proximal isthmus;11 cases were double-structure fixation, 9 cases in 11 were basal type of femoral neck, 2 cases in 11 were neck type, and the femoral shaft fractures were located in the isthmus and the distal isthmus. RESULTS: All patients were followed up for 12 to 27 months. No femoral head necrosis, deformity, delay or nonunion occurred in the patients with single-structure fixation, and no delayed union or nonunion occurred in femoral shaft fractures;At the final follow-up, Harris score of patients with single-structure fixation was 91.8±4.1, with 8 cases were excellent and 2 cases were good. The fractures of patients with dual-structure fixation achieved good union without femoral head necrosis, except 1 case of femoral shaft fracture had delayed union;At the final follow-up, Harris score of patients with dual-structure fixation was 92.4±5.9, 7 cases were excellent, 3 cases were good, and 1 case was fair. CONCLUSION Good reduction and fixation is the key to the treatment of such fractures. Both the single-structure fixation and the dual-structure fixation are good methods, and it should be selected according to the locations of femoral shaft and femoral neck fractures. Single-structure fixation is a good choice for femoral shaft fractures located at the proximal isthmus and basal femoral neck fractures. For isthmus and distal femoral shaft fractures combined with ipsilateral femoral neck fractures, dual-structure fixation is recommended.
Male ; Female ; Humans ; Young Adult ; Adult ; Middle Aged ; Aged ; Femur Neck ; Retrospective Studies ; Femoral Neck Fractures/complications* ; Femoral Fractures/complications* ; Fracture Fixation, Internal/methods* ; Femoral Fractures, Distal ; Treatment Outcome ; Fracture Fixation, Intramedullary/methods*

Femoral head and ipsilateral femoral neck fractures are serious and complicated injuries, which usually yield unsatisfactory results using conventional hip-preserving surgery. The key point of the management and prognosis mainly lies in femoral neck fractures. An apparent and consecutive relationship exists between femoral neck fractures and femoral head fracture-hip dislocation in such injuries. It is believed that disastrous triad of femoral head (DTFH) could summarize these specific injuries, and reflect the injury mechanism and prognostic characteristics. Based on our clinical observation and literature review, DTFH could be divided into three subgroups:TypeⅠ, common DTFH, in which femoral neck fractures occur following femoral head fractures-hip dislocation due to the same trauma; TypeⅡ, iatrogenic DTFH, in which femoral neck fractures come out in the caring process of femoral head fractures-hip dislocation; Type Ⅲ, stressed DTFH, in which femoral neck fractures occur after the management of femoral head fractures-hip dislocation. In the scenario, the line of femoral neck fractures locates distally to the femoral head fractures. Herein, we will discuss clinical characteristics of these types of DTFH.
Humans ; Femoral Fractures/complications* ; Femoral Neck Fractures/complications* ; Femur Head/injuries* ; Fracture Dislocation ; Fracture Fixation, Internal/methods* ; Hip Dislocation/surgery* ; Prognosis

OBJECTIVE: To investigate the biomechanical characteristics of retinaculum in the treatment of femoral neck fractures. METHODS: The CT data of a 75-year-old female volunteer was processed by software to construct an intact femur model and femoral neck fracture model fixed with three cannulated screws, which were divided into models with retinaculum or not. The Von-Mises stress distribution and displacement were compared to analyze the stability differences between the different models to study the mechanical characteristics of the retinaculum in the treatment of femoral neck fractures. RESULTS: In the intact femur, the most obvious displacement appeared in the weight-bearing area of the femoral head, with retinaculum 0.381 37 mm, and without retinaculum 0.381 68 mm. The most concentrated part of the Von-Mises stress distribution was located in the medial and inferior part of the femoral neck, with retinaculum 11.80 MPa, without retinaculum 11.91 MPa. In the femoral neck fracture fixed with three cannulated screws model, the most obvious position of displacement also appeared in the weight-bearing area of the femoral head, with retinaculum 0.457 27 mm, without retinaculum 0.458 63 mm. The most concentrated part of the Von-Mises located at the medical and inferior part of the femoral neck, with retinaculum 59.22 MPa, without retinaculum 59.14 MPa. For the cannulated screws, the Von-Mises force peaks all appeared in the posterior and superior screw, with retinaculum 107.48 MPa, without retinaculum 110.84 MPa. Among the three screws, the Von-Mises stress of the anterior-superior screw was the smallest, which was 67.88 MPa vs 68.76 MPa in the retinaculum and non-retinaculum groups, respectively. CONCLUSION The complete retinaculum has little effect on the stability of intact femur and femoral neck fractures with anatomical reduction after internal fixation, and cannot effectively improve the stability of the fracture end after the fracture.
Female ; Humans ; Aged ; Finite Element Analysis ; Femoral Neck Fractures/surgery* ; Fracture Fixation, Internal ; Bone Screws ; Femur Neck ; Biomechanical Phenomena

For patients with femoral neck fractures who plan to undergo internal fixation, satisfied alignment of fracture ends is an important prerequisite for internal fixation stability and fracture healing. There are many reports on the reduction methods of displaced femoral neck fractures, which can be summarized into three categories:First, the solely longitudinal traction of lower limbs, supplemented by other manipulations such as rotation and compression; Second, the resultant force formed by the longitudinal traction of lower limbs and the lateral traction;the third is accomplished by vertical traction in the axis of femur with hip joint flexed. Each reduction method has its own advantages, but no single method can be applied to all fracture displacement. In this paper, some classical reduction techniques in the literatures are briefly reviewed. It is hoped that clinicians will not be limited to a certain reduction method, they should analyze the injury mechanism and fracture displacement process according to the morphology features and flexibly select targeted reduction methods to improve the success rate of closed reduction of femoral neck fracture.
Humans ; Femoral Neck Fractures/surgery* ; Femur ; Fracture Fixation, Internal ; Fracture Healing ; Traction ; Treatment Outcome

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