Several observational and experimental studies have investigated the potential anabolic effects of statins on undisturbed bone but only a few recent studies have examined the effect of statins on skeletal repair. The goal of the study is to investigate any potential early anabolic effect of the systemic administration of simvastatin in low doses (based on earlier safety and efficacy studies on undisturbed bone) on fracture healing. Fifty-four skeletally mature male New Zealand White rabbits were used for the study. The rabbits were assigned to one of three experimental groups: a control group, and two groups that were orally administrated a diet with 10 and 30 mg/kg/day of simvastatin, respectively. A complete biochemical blood count was performed to exclude drug-induced complications. Half of the animals of each group were sacrificed at 15 days and the other half at 30 days after surgery at which time intervals healing quality was assessed. The bones were subjected to biomechanical testing, histomorphometric analysis and peripheral Quantitative Computed Tomography. In animals received simvastatin of 30 mg/kg/day a significant reduction of BMD, stiffness, and energy absorbed to failure were observed. At 15 days, the amount of cartilaginous callus formation was reduced, and the void space was significantly increased, in the animals of both groups that received simvastatin when compared to the control group (p<
.05). Our results suggest that simvastatin doses of 30mg/ kg/day may have a negative anabolic effect on callus formation in rabbits, whereas doses of 10 mg/kg/day seem not to produce a significant positive or a negative effect, especially at the early stages of fracture remodeling.
The purpose of this retrospective study was to report the results using scarf, first metatarsal osteotomies, in correcting Hallux Valgus deformity with H-V angle >
35°. During the period 2003–2008 we did 23 scarf, first metatarsal osteotomies in 15 patients (8 bilateral).In order to evaluate the effectiveness of this operation, patients were clinically (aofas score) and radiologically (X –ray in 4, 8, 12 weeks) assessed. Mean follow up was 32 months. The results evaluated with the aofas score in order to study the function, the pain and the overall satisfaction of the patients. We had excellent results in 13 %, very good in 48 % good 32% and poor 7 %.There was only one complication and no one infection. According the above results it seems that scarf osteotomy is quite reliable surgical treatment of severe Hallux – Valgus deformity with an increased IM angle.
Optimal entry point for antegrade femoral intramedullary nailing (IMN) remains controversial in the current medical literature. The definition of an ideal entry point for femoral IMN would implicate a tenseless introduction of the implant into the canal with anatomical alignment of the bone fragments. This study was undertaken in order to investigate possible existing relationships between the true 3D geometric parameters of the femur and the location of the optimum entry point. A sample population of 22 cadaveric femurs was used. Computed-tomography sections every 0.5 mm for the entire length of femurs were produced. These sections were subsequently reconstructed to generate solid computer models of the external anatomy and medullary canal of each femur. Solid models of all femurs were subjected to a series of geometrical manipulations and computations using standard computer-aided-design tools. In the sagittal plane, the optimum entry point always lied a few millimeters behind the femoral neck axis (mean=3.5±1.5 mm). In the coronal plane the optimum entry point lied at a location dependent on the femoral neck-shaft angle. Linear regression on the data showed that the optimal entry point is clearly correlated to the true 3D femoral neck-shaft angle (R2=0.7310) and the projected femoral neck-shaft angle (R2=0.6289). Anatomical parameters of the proximal femur, such as the varus-valgus angulation, are key factors in the determination of optimal entry point for nailing. The clinical relevance of the results is that in varus hips (neck-shaft angle • 120o) the correct entry point should be positioned over the trochanter tip and the use stiff nails is advised. In cases of hips with neck-shaft angle between 120o and 130o, the optimal entry point lies just medially to the trochanter tip (at the piriformis fossa) and the use of stiff implants is safe. In hips with neck-shaft angle over 130o the anatomical axis of the canal is medially to the base of the neck, in a “restricted area”. In these cases the entry point should be located at the insertion of the piriformis muscle and the application of more malleable implants that could easily follow the medullary canal should be considered.
A functional score sustem in combination with radiological assesment were used for the postoperative evaluation of the patiends.The mean time of follow-up was 23,5 months.
This study aimed to investigate the ability of vascularized periosteum to induce bone formation under functional loading in vivo. To achieve this, a gap was created in the ribs of mini pigs while functional loading was provided by the respiratory movements. Sixteen juvenile mini pigs were used, assigned in 4 different groups. In group A, a 1,4 cm rib gap was internally fixated (KLS Martin LP 2,0 mm mini plates and screws) and the periosteum flap was entirely preserved and sutured in situ. In group B the same method was followed, but the periosteum adjacent to the gap was completely excised. In group C, the periosteum was preserved; fixation was used and in addition to these, a biologically inert cement was used to obliterate the marrow cavities at the osteotomy sites. Finally, group D (control) included animals in which the gap was left without fixation and periosteum was completely removed. Specimens were harvested at 8 weeks and were evaluated macroscopically, radiologically and histopathologically. Data was analyzed using Fisher’s exact test and non-parametric statistics. Results of this study showed that all gaps created in group A and 10 in 11 in group C demonstrated complete bone formation, bridging the entire defect. No traces of bone formation were observed in groups B and D. These results indicate that rib periosteum has extremely high osteogenic capacity and can bridge large defects in vivo under the following conditions: a) its vascular supply is preserved and b) rigid fixation and functional loading is applied.