| Objective:The treatment of focal and segmental infected bone defect is a difficult problem in the field of orthopedics.Our study aimed at exploring and evaluating:(1)the clinical efficacy of vancomycin-loaded calcium sulfate/calcium phosphate and vancomycin-loaded calcium sulfate in the treatment of focal infected bone defect;(2)the preliminary clinical efficacy of vancomycin-loaded calcium sulfate/calcium phosphate composite as autologous bone volume expander combined with membrane induced technique in the treatment of segmental infected bone defect.Methods:Treatment of focal infected bone defect:A retrospective study of 31 cases with focal infected bone defect was conducted from September 2017 to May 2018.Group A:Vancomycin-loaded calcium sulfate was applied in 10 cases,including 10 males with the mean age of 48 years(48.2±19.22).Etiological distribution was as follows:6 cases were posttraumatic,4 cases were hematogenous osteomyelitis.Site of defect:5 cases of femur,5 cases of tibia.Size of bone defect was 5.66±0.74 cm and the mean filling dose of substitute was 4.49 cc.The average duration of antibiotics use was 45 days.Group B:Vancomycin-loaded calcium sulfate/calcium phosphate composite was used as bone substitute in 21 cases,including 14 males and 7 females.The mean age was 43 years(43.05±17.98).Etiological distribution was as follows:13 cases were posttraumatic,and 8cases were hematogenous osteomyelitis.Site of defect:1 case of humerus,2 cases of femur,8 cases of tibia,2 cases of ischium,8 cases of calcaneus and forefoot.Size of bone defect was 5.28±0.98 cm and the mean filling dose of substitute was 3.95 cc.4 patients received internal fixation,and the average duration of antibiotics use was 36 days.1,3 and6 months after surgery,the rate of new bone formation and substitute absorption were analyzed qualitatively and quantitatively by X-ray and CT scan.Anti-infection efficacy was analyzed by postoperative laboratory examination(WBC,ESR,CRP)and healing of wound.Treatment of segmental infected bone defect:We retrospectively analyzed the clinical data of 12 patients with segmental infected bone defect treated with membrane induced technique from September 2017 to July 2019.The mean age was 39.5 years(18-59 years),with 9 males and 3 females.Etiological distribution:3 cases were post-traumatic,and 9 cases were after internal fixation.Site of defect:1 case of humerus,3cases of femur and 8 cases of tibia.Mean size of defect was 10 cm(6.1-17.2 cm).We applied membrane induced technique after debridement and fixation,and in the second stage of bone defect reconstruction,we filled the defect with mixture of autologous iliac bone and vancomycin-loaded CS/CP at a ratio of 3:1.We evaluated bony union and function of adjacent joint by radiographic examination(X-ray and CT scans),Samantha X-ray score and Paley scale.SF-36 score was used to evaluate patients’quality of life pre and post operatively.The outcomes of laboratory tests(WBC,ESR,CRP)were analyzed postoperatively to determine the recurrence of infection combined with states of healing.Results:Focal infected bone defect:In group A(VA/CS),the mean follow-up was 86.7weeks postoperatively.Preoperatively,ESR,CRP,WBC were 17.1mm/h,5.8mg/L,6.85×10~9/L,compared to that of 27.5 mm/h,15.65 mg/L,6.64×10~9/L 3 months after operation.Infection recurred in 2 cases(tibia)and was managed after surgical debridement,and 3 patients suffered from delayed wound healing,which were cured after dressing change.The rate of new bone formation at 1,3 and 6 months after surgery was15.4%,32.2%and 49.7%respectively,while the absorption rate of bone substitute was47.1%,96.2%and 100%.In group B(VA/CS/CP),the mean follow-up was 61.3 weeks postoperatively.Preoperatively,ESR,CRP,WBC were 12.5 mm/h,15.3 mg/L,6.3×10~9/L compared to that of 9.10 mm/h,4.91 mg/L,and 6.65×10~9/L 3 months after operation.There was no recurrence of infection at 17 months follow-up,and 1 patient suffered delayed wound healing,which was cured after dressing change.The rate of new bone formation at 1,3 and 6 months after surgery was 20.5%,43.7%and 75.2%respectively,while the absorption rate of bone substitute was 23.7%,56.4%and 81.2%.Staphylococcus aureus was the most common bacteria between two groups.Outcomes of rate of new bone formation showed significant statistical difference between the two groups(p=0.001,p=0.025,p=0.000),and results of substitute absorption showed significant statistical difference between the two groups(p=0.000,0.000 and 0.000).There was statistical difference in recurrence rate between the two groups(p=0.034).Segmental infected bone defect:The mean follow-up was 69 weeks(ranging from30 to 142).8 weeks after the first stage operation,the induced membranes of all patients were well formed.The mean union time was 29 weeks(16-48 weeks).6 months after operation,the mean Samantha X-ray score was 5.1(3-6).Union result assessed by Paley scale showed excellent in 12 cases,and the excellent rate of joint function was 75%.Preoperative and postoperative SF-36 score showed that there was statistical difference in all the 9 aspects(p<0.05).From 6 months to last follow-up,none of the 12 patients had infection recurrence or loose of fixation.2 cases had delayed wound healing and were cured after dressing change.Conclusion:The results of our study preliminarily indicated that(1)In the treatment of focal infected bone defect,compared with implant of vancomycin-loaded calcium sulfate as bone substitute,vancomycin-loaded calcium sulfate/calcium phosphate composite could provide stable support for new bone formation with a slower absorption rate,a lower recurrence rate and a better capability of osteogenesis.(2)In the treatment of segmental infected bone defect,membrane induced technique combined with vancomycin-loaded calcium sulfate/calcium phosphate composite as autologous bone supplement not only reduced the need of autologous bone,but also achieved excellent sustained anti-infection effect.Moreover,its osteogenic ability was proper,and it was an effective method for clinical treatment of segmental infected bone defect. |
PDF Full Text Request