Objective
To compare the outcomes between intramedullary nail change and augmentation plating with a retained intramedullary nail for aseptic nonunion of femoral shaft fractures after femoral nailing, and to analyze the cause so as to guide the clinical application.
Methods
Between June 2001 and June 2011, 28 patients with aseptic nonunion of femoral shaft fractures after femoral nailing were treated with intramedullary nail change (11 patients, group A) and augmentation plating with a retained intramedullary nail (17 patients, group B), and the clinical data were analyzed retrospectively. There was no significant difference in age, gender, smoking, location of fracture, Association for the Study of Internal Fixation (AO/ASIF) classification, type of injury, associated injury, type of nonunion, and time of nonunion between 2 groups (P gt; 0.05). The patients were followed up by imaging and the clinical function at regular intervals to observe the callus growth and the recovery condition of the affected limb function, and clinical curative effectiveness was evaluated by Tohner-Wrnch standard.
Results
The operation time, intraoperative bleeding volume, and intraoperative erythrocyte-transported volume in group A were significantly higher than those in group B (P lt; 0.05). There was no significant difference in postoperative drainage volume and hospitalization days between 2 groups (P gt; 0.05). All the incisions healed by first intention, and no nerve and blood vessel injury occurred. All patients were followed up 18.6 months on average (range, 12-36 months). All cases obtained bone union, and time of clinical and radiological bone healing in group B was significantly shorter than those in group A (P lt; 0.05). During follow-up, no following complication occurred: deep incision infection, injuries of blood vessels and nerves, loosening and breakage of internal fixation, loss of reduction, angulated and rotational malunion. According to Tohner-Wrnch standard at last follow-up, the results were excellent in 6 cases, good in 3 cases, and poor in 2 cases, with an excellent and good rate of 81.8% in group A; the results were excellent in 12 cases, good in 5 cases, with an excellent and good rate of 100% in group B; and difference was significant between 2 groups (Z=
—
2.623, P=0.021).
Conclusion
Augmentation
plating with a retained intramedullary nail is an ideal treatment for aseptic nonunion of femoral shaft fractures after femoral nailing and can achieve satisfactory clinical outcomes because it has simpler operation, shorter operation time, less blood loss, and less trauma than intramedullary nail change.
Objective Aseptic loosening of prosthesis is associated with peri prosthetical osteolysis caused by osteoclast activation. Receptor activator of nuclear factor kappa B (NF-κB) l igand (RANKL)/receptor activator of NF-κB (RANK) signalpathway is fundamental in osteoclast activation. To determine whether RANKL antibody can inhibit inflammatory osteolysis in a osteolysis model of mouse. Methods Sixty female BALB/c mice (aged 8-10 weeks, weighing 18-20 g) were selected. The skull bone piece was harvested from 20 mice as the donor of bone graft; the subcutaneous air pouches (2 cm × 2 cm) models were established on the back of the other 40 mice and the skull bone piece was inserted into the air pouches. The 40 mice were equally divided into groups A (negative control group), B (positive control group), C (low-dose RANKL antibody group), and D (high-dose RANKL antibody group). At 1 day after bone graft, 0.5 mL PBS was injected into the pouch of group A, 0.5 mL PBS containing titanium particle into groups B, C, and D. At 2 days before the titanium particle was injected, RANKL antibody (0.1 mL) were injected into the pouch of group C (50 μg/mL) and group D (500 μg/mL), respectively every day for 2 days, and 0.1 mL PBS into groups A and B. At 14 days after bone implantation, the pouchmembranes containing implanted bone were harvested for gross observation and histological analyse. Results All mice survived to the end of experiment, and incisions healed well. The gross observation showed that inflammatory responses, exudation, and vascular proliferation were obvious in group B, and were inconspicuous in groups A, C, and D. The histological analysis showed that significantly more infiltration of inflammatory cells, more obvious bone resorption, more bone collagen loss, and more positive staining area were observed in group B than in groups A, C, and D. There were significant differences in inflammatory cell number, pouch membrane thickness, bone collagen loss, and osteoclast content between group B and groups A, C, and D (P lt; 0.05). Conclusion RANKL antibody can directly blockRANKL/RANK signal pathway, which is an efficient therapy to inhibit bone absorption associated with implant wearing particles.
Objective To introduce the occurrence mechanisms, prevention, and treatment measures of prosthetic aseptic loosening. Methods The recent original articles about prosthetic aseptic loosening were extensively reviewed and analyzed. Results Prosthetic aseptic loosening was a very complex process involving many mechanical and biological aspects. The main mechanical factors included prosthetic materials, shapes and sizes, implant fixation methods (including surfacetreatments), cl inical installation, interface micromotion, stress shielding, implant wear, interface integrity, and peri prosthetic high hydraulic pressure, etc.; the main biological factors included the types and sizes of wear particles, cell-activated responses, cytokine release, enzyme activation and allergic reactions to wear particles, etc.. Many measures should be adopted to effectively prevent and treat it, including improving materials and designs of prostheses, fixation techniques, surgical techniques, and drug treatments. Conclusion Prosthetic aseptic loosening is still a troublesome compl ication after joint replacements in orthopaedics, and more attention should be paid for its effective prevention and treatment.
Objective To evaluate the mechanisms of p42/p44 kinase phosphorylation in cell models and to investigate the effect of simvastatin on the prevention and treatment of aseptic loosening of prosthesis by observing the influence of simvastatin on the levels of tumor necrosis factor α (TNF-α) and monocyte chemoattractant protein 1 (MCP-1) of human peri pheral blood mononuclear cell (PBMC) challenged with titanium particles. Methods PBMC from 45 mL peripheral blood of healthy adult voluntary donators, were separated and cultured, and divided into 5 groups according to different culturemedium: group A, PBMC and titanium particles; group B, PBMC and titanium particles with 1 × 10-5 mol/L simvastatin; group C, PBMC and titanium particles with 1 × 10-6 mol/L simvastatin; group D, PBMC and titanium particles with 1 × 10-7 mol/L simvastatin; and group E, PBMC and titanium particles with the extracellular signal-regulated kinase (ERK1/2) inhibitor U0126. The contents of TNF-α and MCP-1 were tested by ELISA after 24 hours of culture. PBMC were pretreated with different medium grouping as groups A, B, C, D, and E for 60 minutes, and were challenged with titanium particles for 30 minutes and 60 minutes, then the level of ERK1/2 expression was tested by Western blot. Results In groups A, B, C, D, and E, the absorbance (A) values of TNF-α were 1.115 5 ± 0.243 6, 0.693 6 ± 0.354 3, 0.695 7 ± 0.387 3, 0.716 4 ± 0.478 9, and 0.263 5 ± 0.101 6, respectively; and the A values of MCP-1 were 1.421 0 ± 0.105 3, 0.915 1 ± 0.411 3, 1.003 5 ± 0.464 2, 1.102 0 ± 0.353 9, and 0.271 3 ± 0.145 1, respectively. The levels of TNF-α and MCP-1 in group A were significantly higher than others, showing significant differences (P lt; 0.05). There were significant differences between group E and groups B, C, and D (P lt; 0.05), between group B and groups C, D (P lt; 0.05); no significant difference between group C and group D (P gt; 0.05). Western blot results showed the expression of ERK1/2 in all groups at 30 minutes and 60 minutes of culture. The levels of ERK1/2 expression were 1.612 1 ± 0.068 2, 1.078 1 ± 0.072 8, 1.268 7 ± 0.223 1, 1.439 7 ± 0.180 1, and 0.732 0 ± 0.110 4 in groups A, B, C, D, and E, respectively; showing significant differences between groups (P lt; 0.05). Conclusion ERK1/2 is a phosphorylated protein after stimulated by wear particles; it is also one of the most important cell signal ing activation of macrophage. Simvastatin can inhibit the expression of bone absorptive factors induced by wear particles and may be used in the prevention and treatment of aseptic loosening of prosthesis.
ObjectiveTo investigate the expression changes of the receptor activator of nuclear factor-κB ligand (RANKL) in the peripheral blood of patients with aseptic loosening of the implant after total hip arthroplasty (THA) by comparing with that of patients with femoral neck fracture and to analyze the correlation between RANKL expression and aseptic loosening.
MethodsBetween January 2008 and January 2013,the peripheral blood were harvested from 58 patients with aseptic loosening of the implant after THA (trial group) and 63 patients with femoral neck fracture (control group).The 2 groups were well matched,with no significant differences in age and gender (P>0.05).The expressions of the RANKL mRNA and RANKL protein were evaluated by quantitative real-time PCR and Western blot respectively.At the same time,the concentration of RANKL was also measured by ELISA.
ResultsThe expression of the RANKL mRNA in the trial group was 18.30±1.09,which was significantly higher than that of control group (1.00±0.05)(t=125.390,P=0.000).The relative RANKL protein expression values in trial group and control group were 0.856±0.254 and 0.404±0.102 respectively,showing significant difference (t=13.032,P=0.000).The results of ELISA showed that the concentration of RANKL in trial group [(3.553 5±0.129 7) ng/mL] was significantly higher than that of control group [(1.912 3±0.126 2) ng/mL] (t=18.124,P=0.000).
ConclusionThe high RANKL expression in peripheral blood is probably correlated with aseptic loosening of the implant in patients undergoing THA,which possibly is the prognostic factor of aseptic loosening of the implant.
Objective
To review the recent advances in treatment of aseptic femoral shaft nonunion.
Methods
The clinical studies about the treatments of aseptic femoral shaft nonunion in recent years were widely reviewed and analyzed.
Results
There are several surgical methods for aseptic femoral shaft nonunion. Due to uncertain clinical outcome, dynamization of nail should be carefully selected. The exchange nailing is suitable for the hypertrophic nonunion of the isthmal femoral shaft fracture. The exchange lateral plating is suitable for nonunion with obvious malformation. However, wave plate or dual plate should be chosen when the bone nonuinon is combined with the medial defect. The augmentation plating improves the success rate of nailing for femoral shaft nonunion, but it should be carefully selected for patients with obvious deformity or bone defect. Ilizarov technique is suitable for various bone nonunion, especially with complicated or large segmental bone defects. Induced membrane technique is also an important method for the treatment of bone nonunion with large bone defects. The clinical efficacy of the blocking screw remains to be supported by further evidence. Biological stimulants are mainly used for atrophic nonunion, and the clinical efficacy of them alone are still controversial.
Conclusion
Due to lack of comparative studies between different surgical methods, the orthopedist should choose the appropriate treatment according to the individual situations of the patient and the types of bone nonunion.
ObjectiveTo observe the vascularity in periprosthetic tissues of aseptic loosening after total hip arthroplasty (THA) and to explore the relationship between expression of vascularity and osteolysis.
MethodsBetween October 2009 and June 2012, interface tissues were obtained from 22 patients (22 hips) who underwent revision of THA because of prosthetic aseptic loosening, including 12 males and 10 females with the age range of 53-81 years and prosthesis survival range of 6-14 years. The interface tissues were divided into osteolysis group and non-osteolysis group based on preoperative X-ray findings and intraoperative observation. The synovial tissues were harvested from another 8 patients (3 males and 5 females, aged 58-72 years) with osteoarthritis undergoing THA as control group. HE stainging was used to observe the histological character, and low-wear or high-wear was identified according to metal or polyethylene particles amount in osteolysis group. The CD34 immunohistochemical staining was used to mark the blood vessels. Microvessel density and microvessel index were calculated with the use of image analysis software.
ResultsHistological observation showed that wear particles and numerous macrophages/multinucleated giant cells accumulated in the membrane of osteolysis group, while many fibroblasts and synovial cells existed in non-osteolysis group. The microvessels density and microvessel index were significantly lower in non-osteolysis group than those in osteolysis group and control group (P＜0.05), and there was no significant difference in microvessel density and microvessel index between osteolysis group and control group (P>0.05). There were less microvessel density and microvessel index in heavy-loaded metal or polyethylene wear particles areas than those in low-loaded metal or polyethylene wear particles areas (P＜0.05), and there was no significant difference in microvessel index and microvessel index between low-wear group and high-wear group for either polyethylene or metal particles (P>0.05).
ConclusionThe phagocytosis of macrophage in periprosthetic tissues need vicinal microvessels formation and blood supply to some extent. Vascular injury and decreased blood supply at the implant-bone interface seem to be one of the reasons for insufficient implant osseointegration and aseptic loosening.
ObjectiveTo explore the feasibility of establishment of a artificial joint aseptic loosening mouse model by cobalt-chromium particles stimulation.MethodsTwenty-four 8-week-old male severe combined immunodeficient (SCID) mice were divided into experimental group (n=12) and control group (n=12). The titanium nail was inserted into the tibial medullary cavity of mouse in the two groups to simulate artificial joint prosthesis replacement. And the cobalt-chromium particles were injected into the tibial medullary cavity of mouse in experimental group. The survival of the mouse was observed after operation; the position of the titanium nail and the bone mineral density of proximal femur were observed by X-ray film, CT, and Micro-CT bone scanning; and the degree of dissolution of the bone tissue around the tibia was detected by biomechanical test and histological staining.ResultsTwo mice in experimental group died, and the rest of the mice survived until the experiment was completed. Postoperative imaging examination showed that there was no obvious displacement of titanium nails in control group, and there were new callus around the titanium nails. In experimental group, there was obvious osteolysis around the titanium nails. The bone mineral density of the proximal tibia was 91.25%±0.67%, and the maximum shear force at the tibial nail-bone interface was (5.93±0.85) N in experimental group, which were significantly lower than those in control group [102.07%±1.87% and (16.76±3.09) N] (t=5.462, P=0.041; t=3.760, P=0.046). Histological observation showed that a large number of inflammatory cells could be seen around the titanium nails in experimental group, while there was no inflammatory cells, and obvious bone tissue formation was observed in control group.ConclusionThe artificial joint aseptic loosening mouse model can be successfully established by cobalt-chromium particles stimulation.
ObjectiveTo evaluate the effectiveness of locking compress plate (LCP) for the treatment of aseptic diaphyseal humeral nonunions.
MethodsBetween January 2006 and January 2012, 23 patients with aseptic diaphyseal humeral nonuninons were treated with LCP and autologous iliac crest bone graft, and the clinical data were retrospectively analyzed. There were 15 males and 8 females with the average age of 42.5 years (range, 28-60 years). The fracture located at left side in 11 cases and right side in 12 cases. The mechanism of the injury was traffic accident in 15 patients, and falling from height in 8 patients. Fracture was treated by internal fixation in 20 cases and external fixation in 3 cases. And 6 patients had open fractures and other 17 had close fractures. Based on the Weber-Cech classification, 6 cases were rated as atrophic nonunions, and 17 cases as hypertrophic nonuninons. Shoulder function was evaluated by Constant-Murley score and elbow function was evaluated by Mayo score.
ResultsAfter operation, 2 patients had transient radial nerve symptoms of numbness and 1 patient had superficial infection. Primary healing of incision was obtained in the other patients. All patients were followed up 22.22 months on average (range, 16-30 months). Normal range of motion of the shoulder was found in 11 cases; and limited movements of abduction, elevation, and posterior extension were observed in 12 cases. And osseous union was observed clinically and radiographically in all patients. The average union time was 16.95 weeks (range, 12-24 weeks). The average Constant-Murley score was 81.87 (range, 50-98); and shoulder function was excellent in 14 cases, good in 6, and fair in 3. And the average Mayo score was 87.78 (range, 70-96); and the result was excellent in 14 cases, good in 7, and fair in 2.
ConclusionAseptic diaphyseal humeral nonunions can be successfully treated with LCP, coupled with the use of autologous iliac crest bone graft.
Objective Lots of metal ions accumulation and over-expression of receptor activator of NF-κB l igand (RANKL) around the prosthesis could be found in revision of total hip arthroplasty. To investigate the relationship between metal ions and aseptic loosening by observing the effects of Co2+ and Cr3+ ions on the expression of RANKL and osteoprotegerin(OPG) from osteoblast. Methods Osteoblasts were cultured in vitro at the density of 1 × 105 cells/mL, and were divided into 2 groups according to different culture solutions. In control group, osteoblasts were cultured with normal medium without CoCl2 and CrCl3. In experimental group, osteoblasts were cultured with the medium including CoCl2 (10 mg/ L) and CrCl3 (150 mg/L) solutions. The RT-PCR and ELISA methods were appl ied to detect the mRNA expression of RANKL and OPG and protein level at 24 and 48 hours after co-cultured, respectively. Results RT-PCR revealed that the mRNA expression of RANKL and OPG could be found in two groups at 24 and 48 hours after co-cultured, the expression was higher in the experimental group than in control group, especially the expression of RANKL, showing significant difference (P lt; 0.05). At 24 and 48 hours after co- cultured, the ratios of RANKL mRNA to OPG mRNA in the experimental group were 0.860 and 1.232, respectively, which were significantly higher than those in the control group (0.695 and 0.688,P lt; 0.05). ELISA revealed that the protein level of RANKL and OPG in experimental group were significantly higher than those in the control group (P lt; 0.05). Conclusion Co2+ and Cr3+ can stimulate the mRNA expressions of RANKL, OPG and secretion of those protein from osteoblasts, especially increase of the RANKL, which promotes the formation and activation of osteoblasts and the generation of aseptic loosening.
