OBJECTIVE: To explore the advantages and effectiveness of the independently developed intelligent orthopedic robot-assisted distal locking of femoral intramedullary nails. METHODS: Thirty-two adult cadaveric femur specimens were randomly divided into two groups, with 16 specimens in each group. The experimental group used the intelligent orthopedic robot to assist in the distal locking of femoral intramedullary nail holes, while the control group used the traditional method of manual locking under X-ray fluoroscopy. The locking time, fluoroscopy times, and the success rate of first locking were recorded and compared between the two groups. RESULTS: The locking time of the experimental group was (273.94±38.67) seconds, which was shorter than that of the control group [(378.38±152.72) seconds], and number of fluoroscopies was (4.56±0.81) times, which was less than that of the control group [(8.00±3.98) times]. The differences were significant [ MD=73.054 (-37.187, 85.813), P=0.049; MD=1.969 (-1.437, 2.563), P=0.002]. The first locking success rate of the experimental group was 100% (16/16), which was significantly higher than that of the control group (68.75%, 11/16) ( P=0.043). CONCLUSION The efficiency of distal locking of femoral intramedullary nails assisted by the intelligent orthopedic robot is significantly higher than that of the traditional manual locking method under fluoroscopy, as it can markedly reduce the time required for distal locking of femoral intramedullary nails, decrease intraoperative radiation exposure, and increase the success rate of locking.
Humans ; Fracture Fixation, Intramedullary/instrumentation* ; Bone Nails ; Fluoroscopy ; Femur/diagnostic imaging* ; Femoral Fractures/surgery* ; Robotic Surgical Procedures/instrumentation* ; Cadaver ; Adult ; Robotics ; Male

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 the effectiveness of Salter osteotomy combined with subtrochanteric shortening and derotational osteotomy in treating Tönnis type Ⅲ and Ⅳ developmental dysplasia of the hip (DDH) in children and explore the urgical timing. METHODS: A retrospective collection was performed for 74 children with Tönnis type Ⅲ and Ⅳ DDH who were admitted between January 2018 and January 2020 and met the selection criteria, all of whom were treated with Salter osteotomy combined with subtrochanteric shortening and derotational osteotomy. Among them, there were 38 cases in the toddler group (age, 18-36 months) and 36 cases in the preschool group (age, 36-72 months). There was a significant difference in age between the two groups ( P<0.05), and there was no significant difference in gender, side, Tönnis typing, and preoperative acetabular index (AI) ( P>0.05). During follow-up, hip function was assessed according to the Mckay grade criteria; X-ray films were taken to observe the healing of osteotomy, measure the AI, evaluate the hip imaging morphology according to Severin classification, and assess the occurrence of osteonecrosis of the femoral head (ONFH) according to Kalamchi-MacEwen (K&M) classification criteria. RESULTS: All operations of both groups were successfully completed, and the incisions healed by first intention. All children were followed up 14-53 months, with an average of 27.9 months. There was no significant difference in the follow-up time between the two groups ( P>0.05). At last follow-up, the excellent and good rates according to the Mckay grading were 94.73% (36/38) in the toddler group and 83.33% (30/36) in the preschool group, and the difference between the two groups was significant ( P<0.05). The imaging reexamination showed that all osteotomies healed with no significant difference in the healing time between the two groups ( P>0.05). There was no significant difference in AI between the two groups at each time point after operation ( P>0.05), and the AI in the two groups showed a significant decreasing trend with time extension ( P<0.05). The result of Severin classification in the toddler group was better than that in the preschool group at last follow-up ( P<0.05). There was no significant difference in the incidence of ONFH between the two groups ( P>0.05). In the toddler group, 2 cases were K&M type Ⅰ; in the preschool group, 3 were type Ⅰ, and 1 type Ⅱ. There was no dislocation after operation. CONCLUSION Salter osteotomy combined with subtrochanteric shortening and derotational osteotomy is an effective way to treat Tönnis type Ⅲ and Ⅳ DDH in children, and surgical interventions for children aged 18-36 months can achieve better results.
Humans ; Osteotomy/methods* ; Developmental Dysplasia of the Hip/diagnostic imaging* ; Retrospective Studies ; Male ; Child, Preschool ; Female ; Infant ; Femur/surgery* ; Child ; Treatment Outcome ; Hip Dislocation, Congenital/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*

OBJECTIVE: This review summarized the first 10-year progresses and controversies in the concept of anteromedial cortical support reduction, to provide references for further study and clinical applications. METHODS: Relevant domestic and foreign literature on cortical support reduction was extensively reviewed to summarize the definition of positive, neutral, and negative support, anteromedial cortices at the inferior corner, intraoperative technical tips for fracture reduction, radiographic assessment at different periods, comparison between positive versus neutral and medial versus anterior support, and the clinical efficacy of Chang reduction quality criteria (CRQC) and postoperative stability score. RESULTS: Anteromedial cortical support reduction was only focused on the cortex of anteromedial inferior corner, with no concern the status of lateral wall or lesser trochanter. Anteromedial cortex was seldom involved by fracture comminution, it was thicker, denser, and stronger, and was the key for mechanical buttress of the head-neck fragment to share compression load. Positive, neutral, and negative support were also called "extramedullary, anatomic, and intramedullary reduction", respectively. There was hardly seen parallel cortical apposition, but characterized by some kinds of head-neck rotation, for example 10°-15° flexed rotation for positive cortical contact and support. Due to intraoperative compression and postoperative impaction, the status of cortical support may be changed at different time of radiographic examination. The positive medial cortex support was more reliable with less reduction loss than its neutral counterpart, and the anterior cortex contact was more predictive than the medial cortex for final results. As incorporation the bearing of cortex apposition and using a 4-point score, CRQC demonstrated more efficacy and was gradually accepted and applied in the evaluation of trochanteric fracture reduction quality. Postoperative stability score (8 points) provided a assessment tool for early weight-bearing in safety to prevent mechanical failure. CONCLUSION Anteromedial cortical support reduction is a key point for stability reconstruction in the treatment of trochanteric femur fractures. Evidence has definitely shown that non-negative (positive and neutral) is superior to negative (loss of cortical support). There is a tendency that positive cortex support is superior to neutral, but high quality study with large sample size is needed for a clear conclusion.
Humans ; Femur/diagnostic imaging* ; Fracture Fixation, Internal/methods* ; Hip Fractures/diagnostic imaging* ; Treatment Outcome ; Fracture Fixation, Intramedullary/methods*

PURPOSE: End-stage knee osteoarthritis (OA) patients are the primary candidates for total knee arthroplasty (TKA). However, most morphological refinements of TKA prosthesis are based on anatomical data from the knees of healthy individuals. This study aimed to determine whether differences exist in key bony morphological characteristics of the distal femur and proximal tibia between osteoarthritic knees and healthy knees. METHODS: This was a retrospective cross-sectional observational study with a case-control design. Patients who were aged ≥ 50 years, had no history of trauma, fracture, or surgery in the studied knee, and had no obvious knee flexion contracture were included in this study by CT scans. Patients who met the American College of Rheumatology clinical criteria for knee OA were included in the study group. Kellgren-Lawrence grade III or IV knees were studied (for bilateral cases, the more severely affected knee was chosen). Patients who presented with unilateral knee pain or trauma were included in the control group, with CT scans from the opposite (asymptomatic) knee used for analyzing. The studied knee had a Kellgren-Lawrence grade of 0 or I and showed no abnormalities upon physical examination. Archived knee CT scans from 160 patients were divided into 2 groups: the study group (80 moderate-to-severe OA knees) and the control group (80 healthy knees). After 3-dimensional reconstruction and virtual cutting using a CT workstation, 13 morphological parameters of the distal femur and proximal tibia were compared between the 2 groups using independent-samples t-tests. RESULTS: No significant group differences in the femoral anteroposterior dimension (p = 0.797), height of the lateral femoral condyle (p = 0.268), posterior condylar angle (p = 0.240), tibial anteroposterior dimension (p = 0.536), or tibial lateral anteroposterior dimension (p = 0.702) were observed. However, the femoral mediolateral dimension (p = 0.002), distal femoral aspect ratio (femoral mediolateral dimension/femoral anteroposterior dimension) (p < 0.001), height of the femoral trochlear groove (p < 0.001), height of the medial femoral condyle (p < 0.001), tibial mediolateral dimension (p = 0.001), proximal tibial aspect ratio (tibial mediolateral dimension/tibial anteroposterior dimension) (p = 0.004), tibial medial anteroposterior dimension (p = 0.005), and tibial asymmetry ratio (tibial medial anteroposterior dimension/tibial lateral anteroposterior dimension) (p = 0.006) were all significantly greater in the study group. CONCLUSION Knees with moderate-to-severe OA are significantly wider than healthy knees, and OA is a risk factor for increased tibial platform asymmetry. When refining the morphological parameters of TKA prostheses, the specific bony morphological characteristics of OA knees should be taken into account to reduce the potential risk of femoral or tibial component underhang and facilitate optimal balance between tibial component fit and rotational alignment.
Humans ; Osteoarthritis, Knee/pathology* ; Male ; Female ; Cross-Sectional Studies ; Retrospective Studies ; Arthroplasty, Replacement, Knee ; Middle Aged ; Aged ; Case-Control Studies ; Prosthesis Design ; Knee Prosthesis ; Femur/anatomy & histology* ; Tibia/anatomy & histology* ; Tomography, X-Ray Computed ; Knee Joint/diagnostic imaging*

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

Greater trochanteric pain syndrome(GTPS)is a disease caused by structural lesions of the muscles,fascia,ligaments,and bursae near the greater trochanter of the femur.GTPS causes lateral hip joint pain,severely affecting patients' quality of life.Ultrasound has many advantages,such as real-time diagnosis,portable operation,non-radiation,and high resolution,demonstrating a high application value in the diagnosis and interventional therapy of GTPS.This article reviews the current status of ultrasound in the diagnosis and interventional therapy of GTPS and prospects its application.
Humans ; Ultrasonography ; Femur/diagnostic imaging* ; Hip Joint/diagnostic imaging* ; Arthralgia/therapy*

OBJECTIVE: To establish a finite element model of the knee joint based on coronal plane alignment of the knee (CPAK) typing method, and analyze the biomechanical characteristics of different types of knee joints. METHODS: The finite element models of the knee joint were established based on CT scan data of 6 healthy volunteers. There were 5 males and 1 female with an average age of 24.2 years (range, 23-25 years). There were 3 left knees and 3 right knees. According to the CPAK typing method, the knees were rated as types Ⅰ to Ⅵ. Under the same material properties, boundary conditions, and axial loading, biomechanical simulations were performed on the finite element model of the knee joint. Based on the Von Mises stress nephogram and displacement nephogram, the peak stresses of the meniscus, femoral cartilage, and tibial cartilage, and the displacement of the meniscus were compared among different types of knee joints. RESULTS: The constructed finite element model of the knee joint was verified to be effective, and the stress and displacement results were consistent with previous literature. Under the axial load of 1 000 N, the stress nephogram showed that the stress distribution of the medial and lateral meniscus and tibial cartilage of CPAK type Ⅲ knee joint was the most uneven. The peak stresses of the lateral meniscus and tibial cartilage were 9.969 6 MPa and 2.602 7 MPa, which were 173% and 165% of the medial side, respectively. The difference of peak stress between the medial and lateral femoral cartilage was the largest in type Ⅳ knee joint, and the medial was 221% of the lateral. The displacement nephogram showed that the displacement of the medial meniscus was greater than that of the lateral meniscus except for types Ⅲ and Ⅵ knee joints. The difference between medial and lateral meniscus displacement of type Ⅲ knee joint was the largest, the lateral was 170% of the medial. CONCLUSION In the same type of joint line obliquity (JLO), the medial and lateral stress distribution of the knee was more uniform in varus and neutral positions than in valgus position. At the same time, the distal vertex of JLO subgroup can help to reduce the uneven medial and lateral stress distribution of varus knee, but increase the uneven distribution of valgus knee.
Humans ; Finite Element Analysis ; Knee Joint/diagnostic imaging* ; Female ; Biomechanical Phenomena ; Adult ; Male ; Young Adult ; Stress, Mechanical ; Weight-Bearing/physiology* ; Computer Simulation ; Tomography, X-Ray Computed/methods* ; Cartilage, Articular/physiology* ; Range of Motion, Articular ; Menisci, Tibial/anatomy & histology* ; Tibia/anatomy & histology* ; Meniscus/diagnostic imaging* ; Femur/diagnostic imaging* ; Models, Biological

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*