ABSTRACT
BACKGROUND: Tibia open fracture is a common disease, and intramedullary fixation has become the first choice, but the high risk of postoperative infection limits its clinical application.OBJECTIVE: To investigate the early prevention effect of vancomycin-hydroxyapatite (VCM-HA) coated titanium intramedullary nail in a rabbit model of open femoral fracture combined with wound infection.METHODS: Titanium intramedullary nails coated with three different concentrations of VCM-HA were prepared using biomimetic deposition, and subsequently in vitro bacteriostasis experiment was performed. Forty healthy male New Zealand white rabbits were selected and the model of mid-femur open fracture with wound infection was prepared. The rabbit models were then divided into ordinary intramedullary nail, low-, middle- and high-concentration VCM-HA coated intramedullary nail groups (n=10 per group). The wound appearance of the animals was dynamically observed. The body mass, anal temperature, white blood cells and C-reactive protein contents in the venous blood were monitored. The pathological examination of the soft tissue around the fracture and injured limb X-ray were conducted regularly.RESULTS AND CONCLUSION: The prepared VCM-HA coated titanium intramedullary nail exerted obvious antibacterial effects in vitro. The anal temperature in the ordinary nail group was significantly higher than that in the other three groups at 3 days after modeling (P < 0.05). The white blood cells and C-reactive protein contents in the venous blood in the VCM-HA groups were significantly lower than those in the ordinary nail group at 3, 7, 14 and 28 days after modeling (P < 0.05). The hematoxylin-eosin staining of the peripheral tissues displayed the inflammatory response in the VCM-HA groups was milder than that in the ordinary nail group at each time point after modeling. The injured limb X-ray displayed that the callus grew slowly accompanied with sequestration in the ordinary nail group, while the callus growth in the VCM-HA groups was significantly better than that in the ordinary nail group. To conclude, the VCM-HA coated intramedullary nail can effectively reduce postoperative infection in an animal model of open femoral fracture combined with wound infection.
ABSTRACT
Objective To evaluate the mid-term effect of total hip arthroplasty (THA) after failed internal fixation of intertrochanteric fracture.Methods Twenty-one patients treated with THA due to failed internal fixation of intertrochanteric fracture from January 2007 to December 2010 were studied retrospectively.There were 10 males and 11 females,at mean age of 71.7 years (range,66-79 years).Sixteen patients were treated with dynamic hip screws/dynamic condyle screws (DHS/DCS),3 proximal femoral nails,2 hollow screws.Mean interval from internal fixation to THA was 29 months (range,10-79 months).Causes for the failed internal fixation were loosening,cutting,and breakage of screws which generated fracture displacement or nonunion in 19 patients and femoral head necrosis in 2 patients.All patients received THA with uncemented acetabulum cups and proximally long-stemmed,porous-coated titanium femoral components including AML stems for 5 patients and Solution stems for 16 patients.Moreover,greater trochanteric fracture was fixed by Luke wire.Harris hip score were measured before operation and at final follow-up.Radiographs were performed before operation,at 3,6 and 12 months after operation,and at final follow-up to assess the fracture restoration,healing,prosthesis initial fixation,and mid-term survival condition.Results One patient was died due to pulmonary infection 1.5 years after operation.Two patients were lost to follow-up and 18 patients were followed up for 3-5 years (mean,3.9 years).At final follow-up,13 patients regained the ability to walk independently,4 needed support of a cane,1 needed assistance of a walker.There were no signs of loosening,subsidence or rupture of the prosthesis.Mean Harris hip score increased from 25.3 points preoperatively to 80.6 points at final follow-up; the score was excellent in 11 patients,good in 6,good in 1,with the excellent and good rate of 94％.Conclusion THA can improve hip function,patients' quality of life and midterm outcome in salvage of failed internal fixation of intertrochanteric fractures.