Bacterial biofilms are associated with at least 80% of human bacterial infections. The clinical treatment of biofilm infection is still arduous, and therefore many new treatment options are under study, such as probiotics and their derivatives, quorum sensing inhibitors, antimicrobial peptides, phage therapy, organic acids, light therapy, and plant extracts. However, most of these schemes are not mature, and it is important to develop new research directions of anti-biofilms.
Objective To investigate the effectiveness of homemade antibiotic bone cement rod in the treatment of tibial screw canal osteomyelitis by Masquelet technique. Methods A clinical data of 52 patients with tibial screw canal osteomyelitis met the criteria between October 2019 and September 2020 was retrospectively analyzed. There were 28 males and 24 females, with an average age of 38.6 years (mean, 23-62 years). The tibial fractures were treated with internal fixation in 38 cases and external fixation in 14 cases. The duration of osteomyelitis was 6 months to 20 years with a median of 2.3 years. The bacterial culture of wound secretions showed 47 positive cases, of which 36 cases were infected with single bacteria and 11 cases were infected with mixed bacteria. After thorough debridement and removal of internal and external fixation devices, the locking plate was used to fixed the bone defect. The tibial screw canal was filled with the antibiotic bone cement rod. The sensitive antibiotics were given after operation and the 2nd stage treatment was performed after infection control. The antibiotic cement rod was removed and the bone grafting in the induced membrane was performed. After operation, the clinical manifestations, wound, inflammatory indexes, and X-ray films were monitored dynamically, and the postoperative bone infection control and bone graft healing were evaluated. Results Both patients successfully completed the two stages of treatments. All patients were followed up after the 2nd stage treatment. The follow-up time was 11 to 25 months (mean, 18.3 months). One patient had poor wound healing and the wound healed after enhanced dressing change. X-ray film showed that the bone grafting in the bone defect healed and the healing time was 3-6 months, with an average of 4.5 months. The patient had no recurrence of infection during the follow-up period. Conclusion For the tibial screw canal osteomyelitis, the homemade antibiotic bone cement rod can reduce the recurrence rate of infection and obtain a good effectiveness, and has the advantages of simple operation and less postoperative complications.
ObjectiveTo evaluate the bone repair efficacy of the new nano-hydroxyapatite (n-HA)/polyurethane (PU) composite scaffold in the treatment of chronic osteomyelitis in tibia.MethodsA novel levofloxacin@mesoporous silica microspheres (Lev@MSNs)/n-HA/PU was successfully synthesized. Its surface structure was observed by scanning electron microscopy (SEM). Fifty adult female New Zealand rabbits were randomly selected, and osteomyelitis was induced in the right tibia of the rabbit by injecting bacterial suspension (Staphylococcus aureus; 3×107 CFU/mL), which of the method was described by Norden. A total of 45 animals with the evidence of osteomyelitis were randomly divided into 4 groups, and the right medullary cavity of each animal was exposed. Animals in the blank control group (group A, n=9) were treated with exhaustive debridement only. The remaining animals were first treated by exhaustive debridement, and received implantations of 5 mg Lev@PMMA (group B, n=12), 1 mg Lev@MSNs/n-HA/PU (group C, n=12), and 5 mg Lev@MSNs/n-HA/PU (group D, n=12), respectively. At 12 weeks postoperatively, the right tibia of rabbits were observed by X-ray film, and then gross observation, methylene blue/acid fuchsin staining, and SEM observation of implant-bone interface, as well as biomechanical test (measuring the maximal compression force) were performed.ResultsX-ray films showed that the infection were severer than those of preoperation in group A, while the control of inflammation and bone healing of rabbits in group D were obviously better than those at preoperation. The gross observation showed extensive bone destruction in group A, a significant gap between bone tissue and the material in groups B and C, and close combination between bone tissue and the material in group D. The histology of the resected specimens showed that there was no obvious new bone formation around the materials in groups B and C, and there was abundant new bone formation around the periphery and along the voids of the materials and active bone remodeling in group D. The SEM observation of the bone-implant interface demonstrated that no new bone formation was observed at the bone-implant interface in groups B and C. However, bony connections and blurred boundaries were observed between the material and host bone tissue in group D. The biomechanical test showed the maximal compression force of groups B and D were significantly higher than that of groups A and C (P<0.05), but there was no significant difference between groups B and D (P>0.05).ConclusionThe novel synthetic composite Lev@MSNs/n-HA/PU exhibit good antibacterial activities, osteoconductivity, and biomechanical properties, and show great potential in the treatment of chronic osteomyelitis of rabbits.
Objective Platelet-rich plasma (PRP) contains high concentrations of platelets and leucocytes, which play a key role in antimicrobial host defense system. To evaluate the antimicrobial efficacy of autologous PRP in vitro and in vivo and to explore the mechanism of action so as to provide the experimental basis for the prevention and treatment of bone infection. Methods PRP was prepared with the method of two centrifugation from 15 health volunteers. Platelet-leukocytegel (PLG) was obtained after activation of PRP with bovine thrombin. Next, PLG was incubated with Staphylococcus aureus (1 × 106 cfu/mL) in vitro compared with PRP, platelet-poor plasma (PPP) and PBS. Samples were taken out after 2, 4, 6, 8, 12, and 24 hours for bacterial culture and colony count. Thirty-six New Zealand adult rabbits, weighing (2.85 ± 0.11) kg, were divided into 4 groups: PLG (n=10), antibiotic (n=10), infection (n=10), and PBS (n=6) groups. The osteomyel itis models were made by injecting 0.1 mL Staphylococcus aureus suspension (1 × 106 cfu/mL) into the tibial canal in PLG group, antibiotic group, and infection group; equal volumes of PBS was injected in PBS group as a control. Autologous PLG was injected immediately after operation in PLG group. Cefazol in (30 mg/kg) was injected through the auricular vein from 1 hour before operation to 72 hours after operation in antibiotic group, once per 8 hours. No treatment was given in infection and PBS groups. The efficacy of PLG for osteomyel itis prophylaxis was evaluated by microbiological, X-ray and histological observation within 28 days. Results The contents of leucocyte and platelet of PRP were 6.2 times and 5.5 times of whole blood, showing signficant differences ((P lt; 0.05); the contents of leucocyte and platelet of PPP were significantly lower than those of whole blood and PRP ((P lt; 0.05). In vitro test showed that PLG had the most obvious bacteriostasis effect. The bacterial count reached a minimum value at 4 hours after incubation in PLG and at 6 hours after incubation in PRP. PPP had slow and no obvious bacteriostasis effect and PBS had no bacteriostasis effect. At 2, 4, 6, 8, 12, and 24 hours of incubation, the bacterial count reduced significantly when compared PLG with PRP and PPP (P lt; 0.05), when compared PRP with PPP (P lt; 0.05). In PLG group and antibiotic group, 1 rabbit died, respectively; 34 rabbits survived to the end of the experiment. There was no significant difference (P gt; 0.05) in temperature, body weight, erythrocyte sedimentation rate and content of leucocyte between 28 days after operation andbefore operation in 4 groups. After 28 days, the X-ray scores were 2.78 ± 1.39, 1.55 ± 1.48, 4.17 ± 1.25, and 0 in PLG, antibiotic,infection, and PBS groups, respectively, which was significantly higher in infection group than in other 3 groups ((P lt; 0.05). Also, the histological scores were 5.89 ± 3.92, 3.00 ± 2.31, 10.33 ± 4.03, and 0, respectively, which was significantly higher in infection group than in other 3 groups (P lt; 0.05), and was significantly lower in antibiotic group than in PLG group ((P lt; 0.05). The results of bacterial culture showed that the infection rates of PLG group (44.4%) and antibiotic group (20.0%) were significantly lower ((P lt; 0.05) than that of infection group (88.9%). The quantitative analysis of bacteria showed that the number of bacteria was signifcantly lower ((P lt; 0.05) in PLG and antibiotic groups than in infection group. Conclusion PRP forms into PLG after activating, it can inhibit Staphylococcus aureus reproduction in vitro and can effectively prevent bone infection in vivo.
Objective To observe the effect of cationic liposomal ceftazidime (CLC) combined with nano-hydroxyapatite/β-tricalcium phosphate (n-HA/β-TCP) in the treatment of chronic osteomyelitis of rabbits. Methods Thirty healthy New Zealand white rabbits (4-6 months old; weighing, 2-3 kg) were selected to prepare the chronic osteomyelitis models. After 4 weeks, the gross observation, X-ray examination, and bacteriological and histopathological examinations were done; the models were made successfully in 27 rabbits. Of 27 rabbits, 24 were randomly divided into 4 groups (n=6): only debridement was performed in group A; ceftazidime was given (90 mg/kg), twice a day for 8 weeks after debridement in group B; ceftazidime and n-HA/β-TC were implanted after debridement in group C; and CLC and n-HA/β-TCP were implanted after debridement in group D. Before and after treatments, X-ray examination was done, and Norden score was recorded. At 8 weeks after treatment, the specimens were harvested for gross observation and for gross bone pathological score (GBPS) using Rissing standard; half of the specimens was used for histological observation and Smeltzer scoring, the other half for bacteriological examination and calculation of the positive rate of bacteria culture. Results At 8 weeks after treatment, Norden score of group D was significantly lower than that of groups A, B, and C (P lt; 0.05), but no significant difference was found among groups A, B, and C (P gt; 0.05). At 8 weeks after treatment, sinus healed in groups C and D, but sinus was observed in groups A and B; the GBPS scores of groups C and D were significantly lower than those of groups A and B (P lt; 0.05). The Smeltzer scores of groups C and D were significantly lower than those of groups A and B (P lt; 0.05). The positive rates of bacteria culture of groups C (0) and D (0) were significantly lower than those of group A (25.0%) and group B (16.7%) (P lt; 0.05). Conclusion CLC combined with n-HA/β-TCP has good effect in treating chronic osteomyelitis of rabbits, and it has better effect in treating chronic osteomyelitis of rabbits than ceftazidime with n-HA/β-TCP.
Objective To evaluate the limbs shortening and re-lengthening in the treatment of tibial infectious bone defect and chronic osteomyelitis. Methods Between January 2011 and April 2016, 19 cases of tibial infectious bone defect and chronic osteomyelitis were treated with the limbs shortening and re-lengthening technique. There were 13 males and 6 females, aged from 22 to 62 years (mean, 44 years). The causes of injury included traffic accident injury in 16 cases, crush injury in 1 case, and falling from height in 2 cases. One patient was infected after plate internal fixation of closed tibial fracture and 18 patients after external fixation of open tibial fractures (Gustilo type IIIB). The mean previous operation times was 3 times (range, 2-5 times). The time from injury to bone transport operation was 3-11 months (mean, 6.5 months). The bone defect length was 2.0-5.5 cm (mean, 4.3 cm) after debridement. After tibial shortening, limb peripheral blood supply should be checked after release of the tourniquet. Seven wounds were closed directly, 5 were repaired with adjacent skin flap, 5 were repaired with sural neurovascular flap, 1 was repaired with medial head of gastrocnemius muscle flap, and 1 underwent skin grafting. Single arm external fixator or ring type external fixator were used, and completely sawed off between 2 sets of external fixation screws at proximal and distal metaphysis of the tibia. Limb lengthening was performed after 1 week with the speed of 1 mm/d. Results All patients were followed up 10-36 months with an average of 14 months. Two cases delayed healing of the wound after operation, and the other wounds healed primarily. Natural healing of the opposite end of the bone were found in 18 cases, and 1 case had nonunion in the opposite end of the bone because of incomplete removal of lesion bone. There were 5 cases of slow growth of the callus, and healed smoothly by " accordion” technology and injecting red bone marrow in 4 cases, and by bone grafting and internal fixation in 1 case. The time of bone lengthening was 1-3 months, the prolongation index was 1.6-2.7 cm/month (2.20 cm/month). The bone healing time was 7-13 months (mean, 11.1 months). According to tibial stem diagnostic criteria Johner-Wruhs score, 9 cases were excellent, 8 cases were good, 2 cases were fair, with an excellent and good rate of 89.5%. Conclusion Limbs shortening and re-lengthening is an effective method for the treatment of tibial infectious bone defect and chronic osteomyelitis, with the advantages of improving the immediate alignment of the osteotomy ends, significantly shortening the bone healing time of opposite ends of bone.
ObjectiveTo investigate the effectiveness of modified induced membrane technique and pedicled skin (myocutaneous) flap for chronic tibial osteomyelitis in patients with diabetes. Methods A clinical data of 22 diabetic patients with chronic tibial osteomyelitis between January 2017 and March 2019 was retrospectively analyzed. There were 15 males and 7 females with an average age of 52 years (range, 44-65 years). The course of diabetes was 3-12 years (mean, 6.1 years). The course of chronic osteomyelitis was 4 months to 7 years (mean, 3.3 years). The chronic osteomyelitis was rated as type Ⅲ in 9 cases and as type Ⅳ in 13 cases according to the Cierny-Mader classification criteria. Bacterial culture showed 21 cases of single bacterial infection and 1 case of mixed bacterial infection. Preoperative color Doppler ultrasound and CT angiography confirmed that the anterior and posterior tibial arteries were unobstructed. In the first stage of treatment, the bone and soft tissue defects were filled with antibiotic bone cement after the lesion was thoroughly debrided; the length of bone defect was 4-9 cm (mean, 5.6 cm), and the size of soft tissue defect was 5 cm×2 cm to 10 cm×7 cm. After 7-10 days, the bone cement was removed and a new antibiotic bone cement was filled into the bone defect. Meanwhile, the pedicled skin (myocutaneous) flap was performed to repair the wound. After 7-12 weeks, the inflammatory indexes returned to normal, autogenous iliac bone or combined with artificial bone was used to repair the bone defect in the second stage of treatment. The wound healing, bone defect healing, complications, and the number of successful treatments were recorded. The satisfaction of the skin flap efficacy and the function of the affected limb were evaluated. ResultsLocal necrosis of the skin flap occurred in 3 cases after operation, leading to delayed healing of the wound; the other 19 flaps survived successfully, leading to primary healing of the wound. The skin grafts survived completely and the incisions healed by first intention. All cases were followed up 13-28 months with an average of 20 months. The infection recurred in 2 cases within 12 months after operation, and the bone defects healed after treated by modified induced membrane technique. The bone defect healing rate was 100%; the bone healing time was 6-10 months, with an average of 8.9 months; the infection control rate and successful treatment rate were 90.9% (20/22) and 90.9% (20/22), respectively. At 12 months after operation, according to the satisfaction evaluation standard of skin flap efficacy formulated by ZHANG Hao et al., all were satisfied. According to Johner-Wruhs adjacent joint function method, the limb function recovery was excellent in 13 cases, good in 7 cases, and fair in 2 cases, with an excellent and good rate of 90.9%. ConclusionFor the treatment of chronic tibial osteomyelitis in patients with diabetes without vascular occlusion, the modified induced membrane technique and pedicled skin (myocutaneous) flap can repair bone and soft tissue defects, and control the infection at the same time, the short- and medium-term effectiveness are good.
Objective Bioactive borate glass (BG) has good biocompatibil ity and biodegradation. To investigate the feasibilty of bioactive borate glass as a carrier of the antibiotic controlled-releasing by implanting vancomycin-loaded BG (VBG)into the focus of tibia chronic osteomyel itis after debridement. Methods VBG and vancomycin-loaded calcium sulfate (VCS) were prepared with a vancomycin content of 80 mg/g. Sixty-five New Zealand white rabbits, weighing 2.12-3.91 kg (mean, 2.65 kg), were used. The tibia chronic osteomyel itis rabbit models were establ ished by injecting methicill in-resistant Staphylococcus aureus (MRSA, 0.1 mL, 1 × 109 cfu/mL) into the right tibia of 65 rabbits. After 3 weeks of injection, 54 rabbits of successful models were randomly divided into groups A (n=11), B (n=11), C (n=16), and D (n=16). Simple debridement was performed in group A; BG, VCS, and VBG were implanted into the infection sites of groups B, C, and D respectively after thorough debridement. A sample of the debrided tissues was harvested for bacterial examination. The vancomycin serum levels were determined in groups C and D at 1, 2, 4, 10, 24, and 48 hours after operation. The boron serum levels were determined in groups B and D at 10, 24, 48, 72, and 120 hours after operation. After 8 weeks, the effectiveness was assessed radiographically, bacteriologically, and histopathol ogically. Results Ten rabbits died after operation. No vancomycin was detected in group C; the vancomycin level increased gradually, reached the highest level at 4 hours after operation, and then decreased rapidly in group D. No boron was detected in group B; the boron reached the highest serum level at 10 hours after operation, and then decreased gradually in group D. At 8 weeks, calcium sulfate degraded in group C; BG degraded partially in group D; and no obvious degradation was observedin group B. The repair effect was better in group D than in group C. There was no significant difference in radiograph scoring between groups A, B, C and D (P gt; 0.05) before operation, but there was significant difference between group D and groups A, B, C (P lt; 0.05) at 8 weeks after operation. The bacterial culture showed that all the MRSA results were positive in 4 groups. At 8 weeks, the negative rates of MRSA examination were 36.36%, 18.18%, 73.33%, and 81.25% respectively in groups A, B, C, and D, showing significant differences between group D and groups A, B (P lt; 0.05). The histopathological observation showed that a large number of new bones formed and no foreign body reaction occurred in group D. The histopathologic scores of groups A, B, C, and D were 6.45 ± 3.62, 7.55 ± 3.36, 4.27 ± 2.91, and 3.81 ± 3.04 respectively, showing significant differences between group D and groups A, B, and between group C and group B (P lt; 0.05). Conclusion VBG can improve the repair of bone defect in the treatment of chronic osteomyel itis.