Dedifferentiated Central Chondrosarcoma: A Clinical, Histopathological, and Immunohistochemical Analysis of 57 Cases.

Dedifferentiated central chondrosarcoma (DCCS) is a rare cartilage tumor with invasive biological behavior and a poor prognosis. To better understand the morphological characteristics of this type of tumor and its internal mechanism of dedifferentiation, we retrospectively analyzed 57 cases of DCCS. A total of 29 female and 28 male patients were included, ranging in age from 20 to 76 years, with a median age of 54 years. Fifty-seven cases of DCCS occurred in the pelvis (n = 29), femur (n = 17), scapula (n = 4), tibia (n = 2), humerus (n = 2), metatarsals (n = 1), fibula (n = 1), and radius (n = 1). Radiologically, DCCS had two different appearances on imaging, with an area showing calcifications of the cartilage forming the tumor juxtaposed to a lytic area with a highly aggressive, non-cartilaginous component. Histopathologically, the distinctive morphological features consisted of two kinds of defined components: a well-differentiated cartilaginous tumor and non-cartilaginous sarcoma. The cartilaginous components included grade 1 (n = 38; 66.7%) and grade 2 (n = 19; 33.3%) cartilage. The sarcoma components included those of osteosarcoma (n = 29; 50.9%), undifferentiated pleomorphic sarcoma (n = 20; 35.1%), rhabdomyosarcoma (n = 3; 5.2%), fibrosarcoma (n = 2; 3.5%), spindle cell sarcoma (n = 2; 3.5%) and angiosarcoma (n = 1; 1.8%). Immunohistochemistry showed that the expression of p53 and RB in the sarcoma components was significantly higher than that in the cartilaginous components, suggesting that these factors play roles in the dedifferentiation process of chondrosarcoma. DCCS is a highly malignant tumor with a poor prognosis. Except for the patients who were lost to follow-up, most of our patients died.

The spatial differences in bone mineral density and hip structure between low-energy femoral neck and trochanteric fractures in elderly Chinese using quantitative computed tomography.

The purpose of this study was to investigate the differences in bone mineral density (BMD) and hip structure between femoral neck and trochanteric fractures in elderly Chinese individuals using quantitative computed tomography (QCT). A total of 625 Chinese patients (mean age 75.8 years) who sustained low-energy hip fractures (female: 293 femoral neck, 175 trochanteric; male: 82 femoral neck, 75 trochanteric) were recruited. Each patient underwent a hip QCT scan. The areal BMD (aBMD) of the contralateral normal hip was obtained using a computed tomography X-ray absorptiometry module. Using the bone investigation toolkit (BIT) module, the femoral neck was divided into four quadrants: supero-anterior (SA), infero-anterior (IA), infero-posterior (IP), and supero-posterior (SP). Estimated cortical thickness, cortical BMD, and trabecular BMD were measured in each quadrant. Using the hip structure analysis (HSA) function, several parameters were calculated. Stratified by sex, covariance analyses were applied to compare the femoral neck fractures group with trochanteric fractures group after adjustments for age, height, and weight. In women, trochanteric fractures exhibited lower trabecular BMD and estimated cortical thickness at three quadrants of the femoral neck (IA: P = 0.02, P < 0.01; IP: P < 0.01, P = 0.01; SP: P = 0.01, P < 0.01), and lower aBMD at the trochanter area (P < 0.01); femoral neck fractures exhibited lower cortical BMD and estimated cortical thickness at the SA quadrant (P = 0.04, P = 0.01). Differences in HSA parameters were not statistically significant. Among all parameters, the most valuable ones to discrimination of hip fracture type are estimated cortical thickness of the SA quadrant of femoral neck and the aBMD of the trochanter area. In men, only lower cortical BMD at the SP quadrant and aBMD at the trochanter were found in the trochanteric fractures (P = 0.02, P < 0.01). QCT outcomes indicate that spatial differences are helpful to explore the pathogenesis of different type of hip fractures. In women, trochanteric fractures are related to severer osteoporosis, whereas cortical fragility in the SA region of the femoral neck predominates in cases of femoral neck fractures. In men, trochanteric fractures are related to more bone loss of trochanter.

[Minimally invasive percutaneous plate osteosynthesis for the treatment of acetabulum anterior column fracture with intact true pelvic brim].

OBJECTIVE: To discuss feasibility and clinical effects of minimally invasive percutaneous plate osteosynthesis in treating acetabulum anterior column fracture with intact true pelvic brim. METHODS: From May 2013 to December 2015, 8 patients with acetabulum anterior column fracture with intact true pelvic brim were reviewed retrospectively. According to Judet-Letournel classification, all were simple unstable acetabulum anterior column fracture. Among them, there were 5 males and 3 females with an average age of 42.8 years old ranging from 22 to 63. The injury was caused by crush in 4 cases, smash of heavy object in 3 cases, and falling down in 1 case. The time from injury to operation was ranged from 5 to 19 days with an average of 9.5 days. Preoperative CT showed high anterior column fracture of acetabulum with intact true pelvic brim, the fracture separation was less than 1 cm. All the patients were treated with closed reduction and minimally invasive percutaneous plate osteosynthesis. The quality of fracture reduction, operation time, blood loss, fracture healing time, hip function and postoperative complications were observed and recorded. RESULTS: All patients were followed up from 10 to 19 months with an average of 14.5 months. The quality of reduction was classified as anatomical in 4 patients, imperfect in 3, poor in 1 by Matta's score system. The operation time was 30 to 80 min, averaged 51.3 min;the blood loss was 50 to 120 ml, averaged 86.2 ml; fracture healing time was 10 to 19 weeks, averaged 13.3 weeks. At the latest follow-up, the hip function was evaluated by Merle D'Aubigne scoring system, 5 cases got excellent results, 2 cases in good, and 1 case in fair. No vascular nerve injury, wound infection, bleeding, deep vein thrombosis and other complications occurred in 8 patients. CONCLUSIONS: Minimally invasive percutaneous plate osteosynthesis in treating acetabulum anterior column fracture with intact true pelvic brim has advantages of less trauma, less bleeding, quick recovery and good curative effect, and it is a good surgical procedures for acetabulum anterior column fracture.

Correlation between the prevalence of herniation pits and the α angle of the hip: computed tomography evaluation in healthy Chinese adults.

BACKGROUND: Herniation pits (HPs) commonly develop over time at the femoral head-neck junction in adults, but their cause is still under debate. The purpose of study reported here was to investigate the correlation between the prevalence of HPs of the femoral neck and the alpha angle of the hips of healthy Chinese adults, by using computed tomography (CT). METHODS: Six hundred and seventy Chinese adults (representing 1145 hips) who had no known diseases affecting the proximal femur and had no symptoms of femoroacetabular impingement underwent a 64-slice CT scan for medical purposes that included the hip in the scan range. Their CT data were analyzed for the prevalence of HPs in the femoral necks and for hip alpha angles. RESULTS: The overall prevalence of femoral-neck HPs was 12.5% (143 of 1145 hips). The prevalence in the left versus right femoral necks was 12.1% (69 of 569 hips) versus 12.8% (74 of 576 hips). There was no statistically significant difference between the two sides (χ2 = 0.136; p = 0.712). The prevalence of HPs was greater in men than in women (15.9% vs 7.7%; p < 0.01) and greater in adults older than 30 years than in adults younger than 30 years (χ2= 14.547; p < 0.01). The alpha angles were greater in the 143 proximal femora with HPs than in the 1002 without pits (39.95° ± 6.01° vs 37.97° ± 5.14°; p < 0.01). CONCLUSIONS: The prevalence of HPs of the femoral neck in healthy adults was 12.5%, and the prevalence was greater in men than in women. There is a correlation between the prevalence of HPs and the contour of the femoral head-neck junction. The formation of pits may be attributed to the combination of degeneration and morphologic variances in the femoral head-neck junction.