Purpose： To investigate the mid-term curative effects of the treatment of Pipkin type Ⅳ femoral head fractures using a reconstruction plate and bioabsorbable screws and provide the evidence for clinical practice. Me...Purpose： To investigate the mid-term curative effects of the treatment of Pipkin type Ⅳ femoral head fractures using a reconstruction plate and bioabsorbable screws and provide the evidence for clinical practice. Methods： From February 2010 to September 2014, 21 patients with Pipkin type IV femoral head fractures were treated surgically. There were 13 males and 8 females with an average age of 41.1 years （range, 20 -65 years）. The causes of the fractures included traffic accidents （13 cases）, falls from a height （four cases）, heavy lifting injuries （three cases）, and sport injury （one case）. All patients were followed up with radiography and three-dimensional reconstruction computed tomography and other checks and any complications were actively managed. Closed reduction of fracture-dislocation of the hip was attempted under general anesthesia using the Kocher-Langenbeck approach. Femoral head fractures were treated with internal fixation or excision based on the size of the fracture fragments, whereas acetabular fractures were fixed with a reconstruction plate and screws following anatomic reduction. Results： The incisions healed by primary intention in all patients after surgery, without any infection, deep venous thrombosis, or other complications. All 21 patients were followed up for 36-76 months, with an average follow-up duration of 49 months. Postoperative imaging data showed that all dislocations and fractures were anatomically reduced, and bony union of the fractures was achieved. Heterotopic ossification was found in four patients, post-traumatic osteoarthritis in three, and avascular necrosis of the femoral head in two. At the final follow-up, the assessment of hip joint function according to the Thompson-Epstein scoring scale was excellent in 10 cases, good in six cases, fair in three cases, and poor in two cases. The rate of excellent and good functional outcomes was 76.1%. Conclusion： The mid-term curative effects of a reconstruction plate and bioabsorbable screws in the treatment of Pipkin type IV femoral head fractures is significant, and such the treatment can significantly improve the patient＇s joint function and quality of life.展开更多
Porosity is one of the most important parameters for cement-based materials,which influences the mechanical property,transport property,and durability.The spatial and frequency distributions of local porosity of cemen...Porosity is one of the most important parameters for cement-based materials,which influences the mechanical property,transport property,and durability.The spatial and frequency distributions of local porosity of cement pastes are characterized using X-ray micro-tomography data and treating methods.The 3D spatial distributions for three cement paste specimens with different water cement(w/c)ratios show reasonable heterogeneity.The probability analysis also reveals this heterogeneity:the representative volume element(RVE)size based on porosity maps decreases with w/c ratio firstly,then increases with w/c ratio;and the heterogeneity on the characterized probe size or on the RVE size increases with w/c ratio.Average porosities obtained using the CT method are further compared with those by traditional methods.展开更多
文摘Purpose： To investigate the mid-term curative effects of the treatment of Pipkin type Ⅳ femoral head fractures using a reconstruction plate and bioabsorbable screws and provide the evidence for clinical practice. Methods： From February 2010 to September 2014, 21 patients with Pipkin type IV femoral head fractures were treated surgically. There were 13 males and 8 females with an average age of 41.1 years （range, 20 -65 years）. The causes of the fractures included traffic accidents （13 cases）, falls from a height （four cases）, heavy lifting injuries （three cases）, and sport injury （one case）. All patients were followed up with radiography and three-dimensional reconstruction computed tomography and other checks and any complications were actively managed. Closed reduction of fracture-dislocation of the hip was attempted under general anesthesia using the Kocher-Langenbeck approach. Femoral head fractures were treated with internal fixation or excision based on the size of the fracture fragments, whereas acetabular fractures were fixed with a reconstruction plate and screws following anatomic reduction. Results： The incisions healed by primary intention in all patients after surgery, without any infection, deep venous thrombosis, or other complications. All 21 patients were followed up for 36-76 months, with an average follow-up duration of 49 months. Postoperative imaging data showed that all dislocations and fractures were anatomically reduced, and bony union of the fractures was achieved. Heterotopic ossification was found in four patients, post-traumatic osteoarthritis in three, and avascular necrosis of the femoral head in two. At the final follow-up, the assessment of hip joint function according to the Thompson-Epstein scoring scale was excellent in 10 cases, good in six cases, fair in three cases, and poor in two cases. The rate of excellent and good functional outcomes was 76.1%. Conclusion： The mid-term curative effects of a reconstruction plate and bioabsorbable screws in the treatment of Pipkin type IV femoral head fractures is significant, and such the treatment can significantly improve the patient＇s joint function and quality of life.
基金supported by the National Natural Science Foundation of China(Grant No.51008072)the Fundamental Research Funds for the Central Universities(Grant No.2242014R30014)State Key Laboratory of High Performance Civil Engineering Materials(Grant No.2012CEM008)
文摘Porosity is one of the most important parameters for cement-based materials,which influences the mechanical property,transport property,and durability.The spatial and frequency distributions of local porosity of cement pastes are characterized using X-ray micro-tomography data and treating methods.The 3D spatial distributions for three cement paste specimens with different water cement(w/c)ratios show reasonable heterogeneity.The probability analysis also reveals this heterogeneity:the representative volume element(RVE)size based on porosity maps decreases with w/c ratio firstly,then increases with w/c ratio;and the heterogeneity on the characterized probe size or on the RVE size increases with w/c ratio.Average porosities obtained using the CT method are further compared with those by traditional methods.
