Bone development shows certain regularity with age. The regularity can be used to infer age and serve many fields such as justice, medicine, archaeology, etc. As a non-invasive evaluation method of the epiphyseal development stage, MRI is widely used in living age estimation. In recent years, the rapid development of machine learning has significantly improved the effectiveness and reliability of living age estimation, which is one of the main development directions of current research. This paper summarizes the analysis methods of age estimation by knee joint MRI, introduces the current research trends, and future application trend.
Epiphyses/diagnostic imaging* ; Age Determination by Skeleton/methods* ; Reproducibility of Results ; Magnetic Resonance Imaging/methods* ; Knee Joint/diagnostic imaging*

Child ; Epiphyses ; Fracture Fixation, Internal ; Humans ; Lower Extremity

Objective To develop mathematical models for skeletal age determination with multiple statistic method based on the correlation between age and the growth of the epiphysis of extremitas sternalis of clavicle in Shanxi adolescents. Methods The 562 Shanxi sternoclavicular joint samples （454 cases of modelling, 108 cases of external verification） were scanned by the thin-section computed tomography. After volume rendering was obtained, indicators such as area of epiphysis, area of metaphysis, longest diameter of epiphysis and longest diameter of metaphysis of both extremitas sternalis of clavicle were collected. Indicators such as the ratio of area of epiphysis to area of metaphysis, and the ratio of longest diameter of epiphysis to longest diameter of metaphysis of both sides were calculated. Then multiple linear regression and random forest discriminant models were used to build mathematical models for age determination of adolescents. Results The obtained indicators exhibited a strong correlation with age （r>0.85）. The multiple linear regression model for males and females （all 4 indicators entering the model） based on the ratio of longest diameter of epiphysis to longest diameter of metaphysis and the ratio of area of epiphysis to area of metaphysis had an internal validation accuracy rate （±1.0 year） of over 92% and 108 cases had an external validation accuracy rate of over 70% （±1.0 year）. The out of bag error rates of random forest discriminant models were less than 2% for people over 18.0 years old （≥18.0 years old） and under 18.0 years old. The external validation accuracy rates of the 108 cases were over 80%. Conclusion The regression and discriminant models established in this study have certain reliability and accuracy and can be used in age determination of Shanxi adolescents.
Adolescent ; Age Determination by Skeleton ; Clavicle/diagnostic imaging* ; Epiphyses/diagnostic imaging* ; Female ; Forensic Anthropology ; Humans ; Male ; Models, Theoretical ; Osteogenesis ; Reproducibility of Results

The patient was a female infant aged 1 month and 29 days. She was admitted to the hospital due to convulsions for 6 days and increased blood glucose level for 5 days. She had unstable blood glucose levels. The level of glycosylated hemoglobin was too high to measure. Urine glucose was positive (+ - ++++). The levels of fasting C-peptide and insulin were 0.19 ng/mL and 11.68 μIU/mL respectively. High-throughput sequencing of the genetic endocrine disease gene Panel (412 detected genes, including 49 known diabetes-related genes) showed that the EIF2AK3 gene in the infant had two novel compound heterozygous mutations, c.2731_2732delAG and c.2980G>A, both of which were located in the kinase domain. The infant was diagnosed with Wolcott-Rallison syndrome (WRS). As a rare autosomal recessive disease, WRS is characterized by neonatal diabetes, multiple epiphyseal dysphasia and liver disease. Neonatal diabetes is a prerequisite for the diagnosis of WRS. The EIF2AK3 gene is the pathogenic gene of WRS.
Diabetes Mellitus, Type 1 ; Epiphyses ; abnormalities ; Female ; Humans ; Infant ; Mutation ; Osteochondrodysplasias ; eIF-2 Kinase

Avascular necrosis (AVN) is defined as the cellular death of bone and bone marrow components due to the loss of blood supply, and associated with post-traumatic or non-traumatic events. AVN usually involves the epiphysis of a long bone, such as the femoral and humeral heads, which are susceptible to osteonecrosis. Many studies have been conducted but they were restricted to investigations of femoral head avascular necrosis. The presence of osteonecrosis in the proximal femur may impair biological fixation after total hip arthroplasty. We report a 56-year-old male patient with avascular necrosis located not only at the femoral head, but also in the entire femur, including the medullary cavity, who underwent total hip arthroplasty 2 years earlier along with a review of the relevant literature.
Arthroplasty, Replacement, Hip ; Bone Marrow ; Epiphyses ; Femur ; Head ; Humans ; Humeral Head ; Male ; Middle Aged ; Necrosis ; Osteonecrosis

Chondroblastoma is a rare benign tumor that produces giant cells and cartilage matrix. The tumor occurs in people between 10 and 25 years with slightly higher incidence in males. The condition occurs in the proximal epiphysis of the tibia and humerus, distal epiphysis of the femur, but its occurrence in the talus is relatively rare, accounting for 4% of the total number of chondroblastoma cases. Chondroblastoma is often misdiagnosed as a primary aneurysmal bone cyst, giant cell tumor, chondromyxoid, and lesion of a secondary aneurysmal bone cyst by fibrous dysplasia. The most commonly used surgical method for chondroblastoma is broad curettage with bone grafting. In general, an aneurysmal bone cyst is associated with a second degree chondroblastoma, which is approximately 20%. Chondroblastoma of the talus and secondary aneurysmal bone cysts can be misdiagnosed as primary aneurysmal bone cysts. This paper reports a case of a young male patient with chondroblastoma of the talus, which was initially misdiagnosed as an aneurysmal bone cyst with involvement of the talo-navicular joint.
Aneurysm ; Bone Cysts ; Bone Cysts, Aneurysmal ; Bone Transplantation ; Cartilage ; Chondroblastoma ; Curettage ; Epiphyses ; Femur ; Giant Cell Tumors ; Giant Cells ; Humans ; Humerus ; Incidence ; Joints ; Male ; Methods ; Talus ; Tibia

BACKGROUND: Giant-cell tumor of bone (GCTB) is a locally aggressive primary benign tumor presenting as an expansile osteolytic lesion affecting the epiphysis of long bones. Denosumab halts the osteolysis by giant cells thereby downstaging the tumor, helping in performing less morbid procedures to remove the tumor. Our aim was to report the incidence of local recurrence (LR) in patients operated following neoadjuvant denosumab, to investigate factors associated with LR following extended curettage for GCTB, and to compare the postoperative functional and oncological outcome of patients operated with and without neoadjuvant denosumab. METHODS: A total of 123 patients with a mean age of 29.6 years undergoing extended curettage for GCTB were retrospectively divided into group 1 receiving neoadjuvant denosumab and group 2 operated without denosumab. The mean follow-up period was 35 months. The perioperative characteristics and outcome were compared between the two groups and the factors for LR of GCTB were analyzed. RESULTS: The incidence of LR among patients operated after neoadjuvant denosumab therapy was 42.8% and was significantly high compared to that in patients without denosumab (p < 0.001). On multivariate logistic regression analysis, use of denosumab as a neoadjuvant was the only factor independently associated with LR following surgery (p = 0.002). Patients treated with denosumab had a lower LR-free survival rate (log-rank, p = 0.018). CONCLUSIONS: Denosumab was independently associated with increased LR following surgery for GCTB. Denosumab has to be used cautiously in patients in whom the burden of downstaging the disease outweighs the possible chance of LR.
Curettage ; Denosumab ; Epiphyses ; Follow-Up Studies ; Giant Cell Tumors ; Giant Cells ; Humans ; Incidence ; Logistic Models ; Osteolysis ; Recurrence ; Retrospective Studies ; Survival Rate

BACKGROUND: Ganz surgical hip dislocation via a posterior (Kocher-Langenbeck) approach is a popular procedure in the management of femoroacetabular impingement (FAI). We report the results of surgery performed through an anterolateral (Watson-Jones) approach in the management of anterolateral FAI. METHODS: Twenty-one hips in 20 patients (mean age at the time of operation, 17.3 years) were treated surgically using an anterolateral approach: 12 hips with Legg-Calvé-Perthes disease, three septic hips, three hips with avascular necrosis (combined with slipped capital femoral epiphysis [SCFE], femoral neck fracture, and developmental dislocation of the hip), two hips with epiphyseal dysplasia, and one hip with SCFE. All patients had anterolateral FAI. Surgical hip dislocation was performed in four hips with trochanteric osteotomy. Combined osteotomies were for neck lengthening in 11 hips, varus or valgus osteotomy in the proximal femur in four hips, and pelvic osteotomy in four hips. Clinical results were evaluated using a modified Harris hip score (mHHS). RESULTS: Range of hip flexion and abduction showed statistically significant improvement after surgery; however, the improvement in mean mHHS was not statistically significant. CONCLUSIONS: An anterolateral approach can be used as an alternative to a posterior approach in the management of anterolateral FAI with or without hip dislocation while safely preserving the blood supply to the femoral head and allowing simultaneous procedures in the proximal femur.
Dislocations ; Femoracetabular Impingement ; Femoral Neck Fractures ; Femur ; Head ; Hip Dislocation ; Hip ; Humans ; Legg-Calve-Perthes Disease ; Neck ; Necrosis ; Osteotomy ; Slipped Capital Femoral Epiphyses

BACKGROUND: Prophylactic pinning of the uninvolved side after unilateral slipped capital femoral epiphysis (SCFE) is controversial. The alpha angle, a measurement of femoral head-neck aspherity, was proposed as a predictor of progression of contralateral SCFE with a treatment threshold of greater than 50.5°. The aim of this study was to evaluate its validity in our cohort of patients. METHODS: A retrospective review of a 10-year series of patients who presented with unilateral SCFE was conducted. Minimum follow-up duration to identify contralateral progression was 18 months. Age, sex, ethnicity, and endocrinopathies were noted. Alpha angle measurements of the unaffected hip were performed by two independent observers. The average values of measurements were used for analysis. Univariate and multivariate logistic regression analyses were performed to identify predictors of contralateral progression. A receiver operating characteristic (ROC) curve was generated. RESULTS: There were 43 patients with unilateral SCFE. Seven patients (16.3%) developed contralateral SCFE. There were 31 males (72.1%) and 12 females (27.9%). The mean duration from index surgery to contralateral fixation was 43.9 weeks (range, 16.2 to 77 weeks). The mean alpha angle was significantly higher in the patients with contralateral progression (mean, 50.7°; standard deviation [SD], 5.4°; range, 43.8° to 58.5°) than in the patients without progression (mean, 43.0°; SD, 4.2°; range, 33.0° to 52.5°; p < 0.001). The alpha angle was also identified as a statistically significant predictor of contralateral progression on multivariate analysis (p = 0.02). The intraclass correlation coefficient for interobserver reliability was moderately strong at 0.76 (95% confidence interval, 0.55 to 0.87). The area under the ROC curve was 0.88. The treatment threshold of 50.5° had a sensitivity of 0.43, specificity of 0.94, and number needed to treat (NNT) of 2.7. The ideal treatment threshold derived from the ROC curve was 49.0°, which had a sensitivity of 0.71, specificity of 0.89, and an NNT of 1.7. CONCLUSIONS: Alpha angle is a potential predictor of contralateral hip involvement in children with SCFE who may benefit from prophylactic hip fixation. Results from our series suggest a treatment threshold be 49.0°. However, given the limited sample size and moderately strong interobserver reliability, larger studies are needed to validate our findings.
Asian Continental Ancestry Group ; Child ; Cohort Studies ; Female ; Follow-Up Studies ; Hip ; Humans ; Logistic Models ; Male ; Multivariate Analysis ; Retrospective Studies ; ROC Curve ; Sample Size ; Sensitivity and Specificity ; Slipped Capital Femoral Epiphyses

Unsintered hydroxyapatite (u-HA) and poly-L-lactide (PLLA) composites (u-HA/PLLA) are osteoconductive and biodegradable. Screw (Super-Fixsorb MX30) and plate (Super-Fixsorb MX40 Mesh) systems made of u-HA/PLLA are typically used in small bones in maxillofacial surgeries. After the resection of bone tumors in larger bones, reconstructions with β-tricalcium phosphate (β-TCP) implants of strong compression resistance have been reported. After a resection, when the cavity is hemispheric- or concave-shaped, stabilization of the implanted β-TCP block is necessary. In the current series, u-HA/PLLA were used to stabilize the mechanically strong implanted low-porous β-TCP blocks in six bone tumor cases, including three giant cell tumors of bone, and one case each of chondroblastoma, chondrosarcoma, and parosteal osteosarcoma. The mean age of patients at the time of surgery was 31.3 years (range, 19 to 48 years). The bones involved were two ilia (posterior), a femur (diaphysis to distal metaphysis), and three tibias (proximal epiphysis, proximal metaphysis to epiphysis, and distal metaphysis to epiphysis). Neither displacement of the implanted β-TCP block nor any u-HA/PLLA-related complications were observed. The radiolucent character of the u-HA/PLLA did not hinder radiological examinations for potential signs of tumor recurrence. The method of using u-HA/PLLA components for the stabilization of β-TCP blocks makes the procedure easy to perform and reliable. It can extend the application of β-TCP blocks in reconstruction surgery.
Bone Neoplasms ; Chondroblastoma ; Chondrosarcoma ; Durapatite* ; Epiphyses ; Femur ; Giant Cell Tumors ; Humans ; Hydroxyapatites ; Methods ; Osteosarcoma ; Reconstructive Surgical Procedures ; Recurrence ; Tibia