Influence of high molecular weight polyethylene on viability of osteoblasts and new bone formation / 生物医学工程学杂志

To investigate the influence of high molecular weight polyethylene (HMWP) on the viability of osteoblasts and new bone formation in the process of fracture healing, the osteoblasts derived from adult human bone marrow were cultured in HMWP maceration extract and normal culture medium. The viability of the osteoblasts was measured by MTT assay, and the function of the osteoblasts was detected by use of alkaline phosphatase test kit. The locked double-plating (steel plate and HMWP plate) was implanted and fixed at the artificial fracture of distal femur of dogs. Specimens were gained at 3, 6, 9 and 12 weeks postoperatively, examined with macroscopy, microscope and scanning electron microscope (SEM). The results showed that HMWP did no harm to osteoblasts. There is no significant difference in activities of proliferation and alkaline phosphatase between HMWP maceration extract and normal culture medium at each observation time of at 2,4,8, and 14 dyas (P>0. 05). Bone tissue under the implanted HMWP plate manifested no absorption; the new bones formed under the HMWP plate and gradually matured as time went on. It is demonstrated in this study that HMWP has no adverse influence on the viability of osteoblasts and new bone formation and it can be used as internal fixation implant in treating fractures.

Surgical treatment of complicated distal femoral fractures / 中华创伤杂志

Objective To explore different techniques for treat me nt of complicated distal femoral fractures in order to obtain the best curative effects. Methods A retrospective study was done on the cli nical data of 62 patients (64 sides) with complicated distal femoral fractures a dmitted to our hospital from January 1999 to June 2002. According to AO classifi cation: 20 cases (21 sides) belonged to type A and 42 (43 sides) to type C. The supporting steel of AO femoral condyles were applied in 18 cases (19 sides), loc ked double-plating (steel plate and polyethylene plate) in 20 (21 sides) and th e retrograde intramedullary nail in 24. All cases received scientific and ration al rehabilitative treatment post-operatively. Results The 4-38 months follow up showed that 62 cases go t fracture healing with average healing period of 4.2 months (from 10 weeks to 1 6 months). According to criteria of Kolmert and Wulff, 31 sides were excellent, 28 good but 5 poor with an excellence rate of 75%. Conclusions A majority of treatment results of complicate d distal femoral fractures are satisfactory through rational and reliable intern al fixation. The supporting steel plate is suitable for all distal femoral fract ures; and the retrograde intramedullary nail is the treatment of choice for type A and type C1 fractures. As for types C2 and C3 fractures, the locked double-p lating combined with polyethylene is more effective than the supporting steel pl ate or the retrograde intramedullary nail for it has advantages of reasonable de sign, convenient operation and firm fixation.

Operative treatment of acetebular fractures / 中华外科杂志

<p><b>OBJECTIVE</b>To discuss the diagnosis and operative technology of acetabular fracture.</p><p><b>METHODS</b>41 cases of displaced acetabular fractures were enrolled. CT and 3D-CT were performed before operation to understand the classification of fractures and to determine operative regimen. All cases were fixed by reconstruction plates and screws through the best approach.</p><p><b>RESULTS</b>39 cases were followed up for 1 - 4 years, with an average of 1.5 years. Curative outcomes were assessed by Matta's criteria. Clinically, 16 (53.3%) 30 fresh fractures were excellent, 11 (36.7%) good, 3 (10%) fair. The rate of excellence and goodness was 90%. In 9 cases of old fractures, 2 were excellent, 3 good, 2 fair and 2 poor. The rate of excellence and goodness was 55.6%. Complications consisted of sciatic never injury, necrosis of the femoral head, and heterotopic ossification.</p><p><b>CONCLUSIONS</b>The time of operation, degree of injury, and quality of reduction of fracture are important factors affecting the postoperative function of the hip. The key to enhance the outcome is to verdict the type of fracture, select the proper approach before operation, and precise reduction and appropriate internal fixation during operation.</p>