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.

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.

Aim: To review the operative results and to determine factors that may significantly influence the outcome.

Method: We retrospectively reviewed 38 patients treated with femoral interlocking nailing and tibial external fixation in a 5-year period (1996–2000). Two patients were excluded because of early death. Minimum follow-up was 2 years. There were 29 men and 7 women with a mean age of 27 years. Eight femoral (22%) and 29 tibial fractures (81%) were open. Associated injuries to th head, chest, and abdomen were seen in 17 patients (47%). Concomitant musculoskeletal trauma was present in 30 patients (83%). Final functional results were evaluated according to Karlstrom’s and Olerud’s criteria. Various factors were assessed including age, severity of open fractures, neurovascular injuries, fracture comminution, ligamentous knee injuries, concomittant injuries in the same limb or in the contralateral limb, existence of multiple trauma. Multivariate models were derived to detetermine predictors of outcome.

Results: All femoral fractures and 31 tibial fractures (86%) united without additional intervention. Radiographic femoral union averaged 14 weeks and tibial union 20 weeks. A total of 18 secondary procedures were required. Functional results were excellent or good in 26 patients (72%). Increasing age, fracture comminution and associated injury in the contralateral limb were not influenced the final result. Open grade III tibial fractures (p< 0.03), severity of knee ligamentous injury (p< 0.02) and concomitant trauma to the same extremity (particularly to the ankle and foot – p< 0.02), contributing significantly to an unsatisfactory outcome.

Objective: To evaluate the clinical and radiographic outcomes of unstable proximal femoral fractures treated by minimal invasive technigues.

Method: In a retrospective study, between 1991–2003, 93 patients with closed pertrochanteric femoral fractures were treated with gamma-nail.This intramedullary device was used only for unstable intra and subtrochanteric( A3 and A,B respectively, according A.O. clasiffication) fractures and only in cases which adeguate closed reduction was attainable. There were 32 men and 61women with an average of 76 years( range 50 to 95 years). Immediate weight bearing was permitted in 75 patients. Sixty eight patients were available for clinical and radiographic assesment (at least 1 year F.U.).

Results: At 6 months 92% of the fractures were healed. Complications included intraoperative was: 1 diaphyseal fracture required cerclage wiring ,and postoperative were:2 diaphysial fractures at the distal end of nail, 1migration of the lag screw within the femoral head,2 perforations of lag screw towards cranial,1 infection and 2 nonunions reguired T.H.R. Two patients complained of thigh pain.

Conclusions: Gamma nail is a good minimal invasive implant of unstable proximal femoral fractures, if closed reduction is feasible. Permitts early immobilization and weight bearing even and in elderly patients.

Aims: The purpose of this retrospective review was to analyze our results with the use of the Marchetti-Vicenzi elastic locked nail in femoral shaft fractures. Methods: Between Jan.1994 and Dec.1997, 75 femoral fractures in 73 patients were treated in our department. There were 51 men and 22 women with a mean age of 29 years. All patients were followed to fracture union. In 67 cases (89%) the cause of injury was a R.T.A. According to Winquist and Hansen, there were 8 fractures of type 0 (no comminution), 5 of type I, 22 of type II, 29 of type III and 11 of type IV. Six fractures were open grade II and two were grade IIIa. Multiple injuries were seen in 22 patients (30%). Results: Certain intraoperative complications were encountered in 25 cases (33%). Open nailing was required in 21 fractures (28%) mainly because of the loss of reduction (absence of guide wire) or because the distal pins jammed at the fracture site. Distal locking mechanism problems (bending of protruding locking wire or breakage of safety loops) occurred in 11cases (15%). In 3 patients the distal pins protruded from the anterior cortex and in another 4 breakage of one or more pins occurred during the postoperative period. Delayed union was seen in 7 patients (9%). Five fractures (7%) progressed to non-union. All the non-united fractures were type III or IV. The remaining fractures united after a mean period of 15 weeks. Four fractures (5%) which were located in the distal third, united with signiþcant varus deformity (≥10¡). Shortening (≥2 cm) were seen in 4 patients (5%). There was one deep infection that led to nonunion. Conclusions: Because of the high complication rate in this series, we do not recommend this type of elastic nail for the treatment of femoral shaft fractures.

Aim: This study aimed to investigate the ability of vascularized periosteum to induce bone formation under functional loading in vivo. Method: Sixteen juvenile mini pigs were used, assigned in 4 different groups. In goup A, a 1,4 cm rib gap was internally þxated and the periosteum ßap 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; þxation 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 þxation and periosteum was completely removed. Specimens were harvested at 8 weeks and were evaluated macroscopically, radiologically and histopathologically. Data was analyzed using Fisherñs exact test and non-parametric statistics. Results: Results of this study showed that all gaps created in group A and 10 of 11 in group C demonstrated complete bone formation, bridging the entire defect. No traces of bone formation were observed in groups B and D. Conclusion: 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 þxation and functional loading is applied.

Aim of the study: In the present retrospective report, the clinical and radiographic results of implantation of the Perfecta cementless T.H.R. were analyzed, in patients who were followed for a mean period of 6.9 years.

Material and methods: Between January 1993 – March 1998, 227 Perfecta T.H.R were performed in 214 patients. Five patients died and 14 patients were lost to follow-up, leaving 195 patients (208 T.H.R) available for the study. There were 50 men and 145 women with a mean age at operation of 65 years (27–83). The most common diagnosis was primary osteoarthritis (69%). The patients were assessed clinically using the HHS and radiographically for signs of loosening, polyethylene wear and osteolytic lesions.

Results: There were 14 intraoperative femoral fissures (6%) in the metaphyseal area. The mean HHS at the most recent follow-up was 90. Four patients (2%) had moderate thigh pain. Radiolucent lines around the porous coated part of the components were not observed, and progressive loss of proximal density was not seen. In the cup, a measured migration (> 3mm) in the plain films was not seen, while stem migration was noticed in 5 hips but the patients were asymptomatic. Fifteen cups (7%) had polyethylene wear and in 12 hips (6%) small osteolytic lesions were seen. Seven hips (3%) were revised: 2 hips for deep infection, 2 for acetabular loosening and 3 for instability.

Conclusions: Our clinical and radiographic medium – term results of Perfecta cementless T.H.R are very encouraging.

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.

Aim: Complex tibial plateau fractures, Shatzker type VI, rare in the past, became more common nowadays because of high energy injuries. These complex fractures usually accompanied by compromised skin and soft tissue envelope requires deliberate planning as treatment in the past invite a high rate of complications.

Materials and method: During a period of 24 months, 16 fractures of tibial plateau, Shatzker VI, were treated in 16 patients, all regarding vehicle accidents.11 patients were men and 5 women with a mean age of 42 years old (27–67).There were 2 open and 14 closed fractures (3 type I, 8 type II and 3 type III according to Tscherne’s classification).All cases were treated with circular external fixators (hybrid), whereas 9 of them needed additional mini internal fixation (one or two screws).

Results: 14 patients were evaluated with a mean period of follow up 1.9 years. Healing was achieved in all 14 cases with a mean period of 16 weeks (12–24).Fixator removal was performed when bone healing was completed. There was no deep infection. 12 patients at the end of treatment had a range of motion between 0° – 120°. 3 fractures developed a malunion (1 valgus deformity, 2 anterior angular deformity). Radiographic evidence of arthritis appeared in 2 patients during follow up. Pin tract infection occurred in one case, treated with antibiotics.

Conclusion: The use of circular external fixators (three olive wires to tibial plateau) obtains good stabilization while allows early joint motion, protects soft tissue envelope and in combination with minimal internal fixation achieves satisfactory reduction of comminuted fractures making the technique promising for the management of these complex fractures.