BackgroundAtrophic nonunion of femoral shaft fracture after intramedullary (IM) nailing is uncommon. The treatment for femoral shaft aseptic atrophic non-union remained controversial. The aim of this study was to compare the surgical results between exchanging reamed nailing (ERN) and augmentative antirotational plating (AAP) for femoral shaft aseptic atrophic nonunion.MethodsWe retrospectively reviewed the patients with femoral shaft nonunion between the year of 2014 and 2015. The patients with nonunion after plate osteosynthesis, septic nonunion, hypertrophic nonunion, additional surgery during revision surgery were excluded. All the patients were followed up at least 12 months.ResultsOverall, the union rate after revision surgery was 70.8%. The union rate was significantly higher in the AAP group than in the ERN group. Operating time was also significantly shorter in the AAP group. Regarding the location of nonunion, the union rate was comparable between groups for isthmic nonunions. However, for non-isthmic nonunions, the union rate was significantly higher and operating time was significantly shorter in the AAP group.ConclusionAAP showed an overall higher union rate for management of femoral shaft aseptic atrophic nonunion compared with ERN. Especially for non-isthmic femoral shaft atrophic nonunions, AAP provided a significantly higher union rate and significantly shorter operating time.

Purpose. To identify the predicting factors for union and infection after applying the induced membrane technique (IMT) for segmental tibial defects. Methods. A systematic review was carried out following the PRISMA guidelines. All databases were searched for articles published between January 2000 and February 2018 using the keywords “Masquelet technique” and “induced membrane technique.” Studies in English reporting more than 5 cases with accessible individual patient data were included. A meta-analysis was performed. Odds ratios (OR) with 95% confidence intervals were calculated. Results. After reviewing, 11/243 studies (115 patients) were finally selected. The mean age of the patients was 43.6 years (range: 18-84 years), and the mean length of the tibial defect was 5.5 cm (range: 0-20 cm). The multivariate logistic regression analysis revealed that the risk factors of postoperative infection after IMT were infected nonunion (p=0.0160) and defect length ≥7 cm (p=0.0291). Patients with postoperative infection after IMT had a lower union rate (p=0.0003). Additionally, the use of an antibiotic polymethyl methacrylate cement spacer reduced the need for surgical revision (p=0.0127). Multiple logistic regression indicated no direct association between the union rate and length of the bone defect. Conclusions. IMT is a reliable and reproducible treatment for segmental tibial defects. However, initial infected nonunion and defect length greater than 7 cm are risk factors for post-IMT infection, and post-IMT infection was statistically related to nonunion.

A composite biodegradable polymeric model was developed to enhance tendon graft healing. This model included a biodegradable polylactide (PLA) bolt as the bone anchor and a poly(D,L-lactide- co -glycolide) (PLGA) nanofibrous membrane embedded with collagen as a biomimic patch to promote tendon–bone interface integration. Degradation rate and compressive strength of the PLA bolt were measured after immersion in a buffer solution for 3 months. In vitro biochemical characteristics and the nanofibrous matrix were assessed using a water contact angle analyzer, pH meter, and tetrazolium reduction assay. In vivo efficacies of PLGA/collagen nanofibers and PLA bolts for tendon–bone healing were investigated on a rabbit bone tunnel model with histological and tendon pullout tests. The PLGA/collagen-blended nanofibrous membrane was a hydrophilic, stable, and biocompatible scaffold. The PLA bolt was durable for tendon–bone anchoring. Histology showed adequate biocompatibility of the PLA bolt on a medial cortex with progressive bone ingrowth and without tissue overreaction. PLGA nanofibers within the bone tunnel also decreased the tunnel enlargement phenomenon and enhanced tendon–bone integration. Composite polymers of the PLA bolt and PLGA/collagen nanofibrous membrane can effectively promote outcomes of tendon reconstruction in a rabbit model. The composite biodegradable polymeric system may be useful in humans for tendon reconstruction.