Antibiotic cement-coated intramedullary nail is cost-effective for the initial treatment of GAⅢ open tibia fractures

ObjectiveTo evaluate the cost-effectiveness of antibiotic cement-coated intramedullary nails (IMN) in the initial management of Gustilo-Anderson type Ⅲ (GAIII) open tibia fractures.MethodsA break-even equation was used to analyze the costs associated with antibiotic cement-coated IMN and postoperative infection following GAⅢ open tibia fractures. This equation produced a new infection rate, which defines what percentage the antibiotic coated IMN needs to decrease the initial infection rate for its prophylactic use to be cost-effective. The postoperative infection rate used for calculations was 30%, a value established in current literature for these fracture types (6–33%). The institutional costs associated with a single operative debridement and resultant inpatient stay and treatment were determined. A sensitivity analysis was conducted to demonstrate how various total costs of infection and different infection rates affected the break-even rate, the absolute risk reduction (ARR), and the number needed to treat (NNT).ResultsFinancial review yielded an average institutional cost of treating a postoperative infection to be $13,282.85. This number was inclusive of all procedures during an inpatient stay. The added cost of the antibiotic coated implant to the hospital is $743.42. Utilizing the break-even formula with these costs and a 30% initial infection rate, antibiotic coated IMN was economically viable if it decreased infection rate by 0.056% (NNT = 1,785.714).ConclusionThis break-even analysis model suggests the initial use of an antibiotic coated IMN in the setting of GAⅢ open tibia fractures is cost-effective.     

Proximal avulsion of five ligaments and revised diagonal principle in tibial plateau fractures

PurposeThe aim of the study was to analyze the incidence of proximal avulsion of the five main ligaments and to revise the diagonal tension/compression concept in tibial plateau fractures.MethodsComputed tomographic images of 1263 cases of tibial plateau fractures were retrospectively analyzed by the OTA/AO classification and four-column nine-segment classification. The correlation between proximal avulsion of five ligaments and the injury mechanism was analyzed.ResultsIn total, 1263 tibial plateau fractures in 1253 patients were included. A total of 92 cases (7.3%) associated with proximal avulsions were identified among the 1263 tibial plateau fracture cases obtained from our institution's database. The 92 avulsions occurred in 82 patients, among whom 10 patients had two different avulsions in a single knee. The incidence of proximal avulsion fracture of the medial and lateral collateral ligament was 3.6% (45/1263) and 2.1% (26/1263), respectively. The incidence of avulsion of the anterior cruciate ligament and avulsion of the posterior cruciate ligament was much lower at 0.2% (2/1263) and 0.1% (1/1263), respectively. Proximal avulsion of the patellar ligament occurred in 18 cases (incidence rate = 1.4%). Several combinations of injuries, composed of distal tibial plateau fractures and proximal avulsion of ligaments, were identified.ConclusionsAmong the patients with tibial plateau fracture, the incidence of proximal avulsion of the five ligaments was 7.3% (92/1263). The four-column and nine-segment classification is an exhaustive method for recording injuries in these ligaments. The revised diagonal injury concept is useful for understanding the injury mechanism and choosing the appropriate surgical strategy.     

双头自动加压新型外固定支架的设计和临床应用

目的:设计股骨转子间骨折双头自动加压新型外固定支架并探讨其临床应用。方法:在单侧成角外固定器和Ilizarov技术的基本原理的基础上,研制双头自动加压新型外固定支架。2006年10月至2010年12月,用此新型外固定器治疗老年股骨转子间骨折120例,男67例,女53例;年龄60～93岁,平均76.7岁。按Evans标准:Ⅰ型65例,Ⅱ型41例,Ⅲa型10例,Ⅲb型2例,Ⅳ型2例。手术时间为伤后0～11d,平均5d。按照Sanders评分标准对术后患者的髋关节功能进行评估。结果:116例获得随访,时间2～24个月,平均12个月。骨折全部愈合,愈合时间10～13周,平均12周。术后针孔感染5例,无深部感染发生,无骨折不愈合及髋内翻,髋关节功能恢复良好。根据Sanders评分标准对髋关节功能进行评定,疼痛(9.07±0.41)分,行走(9.23±1.00)分,功能(9.42±1.10)分,运动肌力量(9.31±1.06)分,日常活动(9.22±1.03)分,X线评估(10.00±0.00)分,总平均分(56.27±4.16)分,其中优106例,良6例,差4例。结论:双头自动加压外固定器使用方便,兼有加压和微创双重功能,是治疗高龄股骨转子间骨折患者较理想方法。     

Bone regeneration after marginal bone resection in two-stage treatment of chronic long bone infection - a combined histopathological and clinical pilot study

IntroductionIn chronic bone infection, marginal bone resection avoids large and difficult to reconstruct bone defects. However, there is still a lack of knowledge on bone regeneration during chronic bone infection and bone healing capability after marginal bone resection. Therefore, the purpose of this study was to investigate the clinical and histopathological outcomes after marginal bone resection in chronic long bone infection. We hypothesized that there is a regenerative bone healing potential after marginal bone resection that results in an acceptable clinical outcome and improved pathohistological bone healing parameters during treatment.Materials and methodsNine patients were treated for chronic bone infections in a two-stage manner with marginal bone resection of the infected area and the placement of an antibiotic-loaded polymethyl methacrylate (PMMA) spacer at stage one followed by bone reconstruction at stage two combined with systemic antibiotic therapy. Comparable bone samples were harvested at the border region between vital and necrotic bone area during stage one and the identical location during stage two. Control bone samples were harvested from five healthy patients without bone infection. Clinical outcome in terms of infection eradication and bone consolidation were assessed. The phenotypic changes of osteocyte and morphological changes of lacunar-canalicular network were investigated by histological and immunohistochemical staining between the two observation periods. Furthermore, expression levels of major bone formation and resorption markers were investigated by immunohistochemical and tartrate-resistant acid phosphatase (TRAP) staining.ResultsThe clinical results with a follow-up of 12.9 months showed that eight of nine patients (88.9%) achieved bone consolidation after a planned two-stage procedure of marginal resection of necrotic bone and consecutive reconstruction. In four of the nine patients (44.4%), additional marginal debridements after stage two had to be performed. After marginal resection at stage one, the improved bone formation ability at stage two was demonstrated by significantly lower percentage of empty lacunae, significantly more mature osteocytes and higher BMP-2 positive cell density, whereas decreased resorption was indicated by significantly lower osteoclast density and RANKL/OPG ratio. In patients requiring additional debridement compared to patients without additional debridements, a significantly higher percentage of empty lacunae was found at stage one.ConclusionMarginal bone resection combined with local and systemic antibiotic therapy is a feasible treatment option to avoid large bone defects as bone from the marginal resection area seems to have good regenerative potential. Despite a high revision rate of 44.4%, this technique avoids large bone resection and revisions can be done by further marginal debridements.