【Abstract】 Objective To explore the biomechanical properties of a new intramedullary controlled dynamicnail ing (ICDN). Methods Ten pairs of specimens of adult femurs, with the age of 18 to 55 years, were divided into twogroups (groups A1 and B2, n=10). The length of the specimens was (438 ± 10) mm , and the external diameter was (26.4 ± 1.5) mm. The specimens of the two groups were osteotomized transversely after the biomechanical test. ICDNs and GK nails were randomly implanted into the femurs, respectively (groups A2 and B2). Torsional, bending and axial compressive tests were made in each group, and the effect of dynamic compression between the fracture fragments was tested. Results The resistance to compression of groups A1, B1, A2 and B2 were (0.19 ± 0.18) × 106, (0.22 ± 0.12) × 106, (1.67 ± 0.68) × 106 and (0.86 ± 0.32) × 106 N/mm, respectively. There was statistically significant difference between groups A2 and B2 (P lt; 0.01). The bending stiffnesses of coronal section of groups A1, B1, A2 and B2 were (0.94 ± 0.25) × 103, (1.10 ± 0.21) × 103, (0.70 ± 0.22) × 103, (0.64 ± 0.21) × 103 N/mm, respectively. The bending stiffness of sagittal plane of groups A1, B1, A2 and B2 were (1.06 ± 0.26) × 103, (0.96 ± 0.25) × 103, (0.67 ± 0.25) × 103, (0.61 ± 0.18) × 103 N/mm, respectively. There were no statistically significant differences between groups A1 and B1 or between groups A2 and B2 (P gt; 0.05). When the torque was 5 Nm, the torsional stiffness of groups A1, B1, A2 and B2 were (4.00 ± 2.54), (4.76 ± 1.93), (0.50 ± 0.63), (0.35 ± 0.31) Nm/°, respectively. When the torque was8 Nm, the torsional stiffness of groups A1, B1, A2 and B2 were (4.30 ± 3.27), (3.94 ± 2.01), (0.42 ± 0.52), (0.36 ± 0.18) Nm/°, respectively. There were statistically significant differences between groups A1 and A2 or between groups B1 and B2 (P lt; 0.05), and no statistically significant difference between between groups A2 and B2 (P gt; 0.05). The average maximal pressure generated between the fracture fragments which were fixed with ICDN was 21.6 N, and the pressure between the fracture fragments which were fixed with GK nail ing could not be tested. Conclusion The design of ICDN conforms to the special anatomical structure of the femur. ICDN could provide a completely different structure, a different fixation principal and a more balancedfixation than GK nail. ICDN incorporates the flexible and rigid fixation, which is l ikely to be the trend of the fracture fixation.
Objective To explore the clinical effect and complications of lumbar plexus block through different approaches on perioperative analgesia in aged proximal femur surgery, and find the best method for analgesia in these patients. Methods From January to December 2015, 150 elderly patients scheduled for proximal femur surgery were randomly divided into three groups: psoas compartment block (PCB group, n=50), Winnie " 3 in 1” block (Winnie group, n=50), and fascia iliaca compartment block (FICB group, n=50). Twelve hours before surgery, guided by ultrasound and nerve stimulator, lumbar plexus blocks were performed in all the patients, then patient-controlled analgesia (the formula and the usage were the same) was done. All patients received epidural anesthesia, and were maintained postoperative analgesia for 72 hours. If Rest Visual Analogue Scale>3 or Initiative Movement Visual Analogue Scale>4, sufentanyl 10 μgi.m. was given. Muscle strength grades and complications were recorded. Anesthetic effect of sensory block of femoral, lateral femoral cutaneous, and obturator nerves were measured and recorded too. Results There were two cases of epidural block, and one case of puncture point bleeding in group PCB; no complication in the other groups was found. There was no remedy for inadequate analgesia in the three groups. Compared with group PCB, the muscle strength grades during postoperative 24–72 hours in group FICB were higher (P<0.05). The successful rate of the block of lateral femoral cutaneous nerves was 64%, 91% and 96% in group Winnie, group PCB and group FICB, respectively, and the differences between the three groups were all statistically significant (P<0.05). The successful rate of the block of obturator nerves in group FICB (62%) was lower than that in group PCB (89%) and Winnie group (84%) (P<0.05). Conclusion Continuous fascia iliaca compartment block on perioperative analgesia in aged proximal femur surgery, with exact effect, less complications and simple operation, is better than the psoas compartment block and Winne " 3 in 1” nerve block.
Objective To investigate the effectiveness on the re-fracture of the femur with occult infection by using non-contact locking plate which was placed under the deep fascia. Methods Clinical data of 12 cases of occult infective re-fracture after femoral fracture operation were retrospectively analysed between January 2010 and December 2014. There were 8 males and 4 females with an age of 28-69 years (mean, 42.8 years). Femur re-fractured in 5 cases after 3 days to 4 weeks (mean, 10.6 days) of removal of internal fixation, including 4 cases of plate fixation and 1 case of intramedullary nail fixation; femur in 7 cases re-fractured because of breakage of internal fixator after 7-16 months (mean, 9.3 months) of internal fixation, including 5 cases of plate fixation and 2 cases of intramedullary nail fixation. The tissues near the fracture were collected for bacteria culturing and pathological examining. All the patients were treated by debriding the site of the fracture, bridging with the non-contact locking plate, and transplanting with granulated cancellous bone autograft. Intravenous infusion of antibiotics were used for 2-3 weeks after operation and oral administration for 4 weeks. The X-ray films were taken regularly and the function of the knees were evaluated by the Hospital for Special Surgery (HSS) score system. Results The results of bacteria culturing were positive in 8 patients and negative in 4 patients, and the pathological results of all the patients were confirmed to be chronic bone infection. All the fractures healed with no signs of exudation and ulceration of the incisions. The 12 patients were followed up 18-36 months (mean, 29.6 months). The fracture healed well and no re-fracture occurred. The fracture healing time was 14-22 weeks (mean, 18 weeks). At last follow-up, the function of the knee joint was excellent in 9 cases and good in 3 cases according to HSS score system. Conclusion The treatment of re-fractures after femur fracture operation needs to determine whether there is an occult infection, and non-contact locking plate placed under the deep fascia is an effective way for the re-fracture.
To evaluate the cl inical results of less invasive stabil ization system (LISS) for femur supercondylar and intercondylar fractures. Methods From March 2004 to November 2005, 47 patients with 49 intercondylar and supercondylar fractures were treated. Of all the patients, there were 34 males and 13 females with an average of 39.7 years (range 19-56 years). The locations were left side in 21 cases and right side in 28 cases. Fracture was caused by traffic accident in 31 cases, fall ing in 8 cases, violence in 6 cases and others in 2 cases. Forty-nine fractures included 14 intercondylar fractures, 21supercondylar fractures and 14 intercondylar and supercondylar fractures; 32 closed fractures and 17 open fractures. According to the AO typing, there were 6 type 33-A1, 8 type 33-A2 , 10 type 33-A3, 7 type 33-C1, 3 type 33-C2 and 15 type 33-C3. The disease course was 30 minutes to 6 days. Articular surface reduction was first performed, then the LISS plate was inserted via two incisions and locking screws were used later. Results The average operation time was 126 minutes (range 48-248 minutes). The blood loss was 180 mL(range 60-1 200 mL). The average follow-up time was 18.6 months (range 12-23 months). There were 4 patients with AP angular deformity and 5 patients with lateral angular deformity (range 2-5°). External rotation deformity was presented in 2 patients. There were no plate breakage, screw loosen and fixation failure. Average bone union time was 5.6 months (range 3-8 months) without infection case. Six cases were treated with il iac bone transplantation for delayed union. Conclusion LISS is one kind of effective treatment to femoral intercondylar and supercondylar fractures.