Chronic infection following total hip arthroplasty: Any role for ilizarov?

Context: Treatment of chronic infection following total hip arthroplasty (THA) poses challenges in revision and in salvage surgeries such as resection arthroplasty. Aims: We evaluated the results and role of Ilizarov fixator in resection and revision for infected hip arthroplasty. Settings and Design: This was a retrospective descriptive study. Subjects and Methods: We reviewed 73 patients treated between 2004 and 2014 with follow-up of 4.3 ± 1.8 years. Forty-three patients underwent two-stage revision (with interim antibiotic spacer), whereas 30 patients underwent Ilizarov-assisted resection arthroplasty. We supplemented eight patients with unstable spacers with Ilizarov apparatus. We evaluated patients for recurrence of infection, hip function and stability. Statistical Analysis Used: Descriptive methods. Results: Eight patients with Ilizarov supplementation of spacer went on to have stable hips. Two patients who had intraoperative stable spacers developed spacer dislocation. Pseudarthroses in resection group remained stable in all patients except one who had early dislocation which we managed by realigning the fixator. There was no mortality. We eradicated infection in 68/73 patients (93.2%). We converted three patients of spacer application to resection arthroplasty. The mean Harris Hip Score improved from preoperative value of 43.3 ± 18.8 to 67 ± 10.4 (81.4 ± 9 in revision and 52.6 ± 11.8 in resection groups). Conclusions: We recommend Ilizarov supplementation in temporary spacers with intraoperative instability. Ilizarov fixator improves stability and helps mobilization of resection arthroplasty and staged revision using spacers done for chronic post-THA infections

A simple treatment strategy for peri-implant fracture of the humerus: Report of two cases

Background: Non-prosthetic peri-implant fractures and under reported entities and their optimal management strategies are uncertain. Case details: We present two cases of peri-implant fractures of distal humerus with long dynamic compression plate in situ. We report for the first time a strategy of implant retention, open reduction with small incision, minimal internal fixation with K-wires and supplementary fixation with bilateral external fixator using Joshi's External Stabilizing System (JESS). Both fractures showed signs of union at three months from surgery. The fixators were removed at four months under sedation and patients were advised aggressive active mobilisation of the elbow. This resulted in sound union of the fracture with preservation of elbow motion without any complications. Conclusion: We recommend this method, as it is a simple, safe, effective and reproducible technique for management of peri-implant fractures of the humerus

Outcome of complex tibial plateau fractures with Ilizarov external fixation with or without minimal internal fixation

Purpose: To evaluate the clinico-radiological outcome of complex tibial plateau fractures treated with Ilizarov external fixation with or without minimal internal fixation. Methods: This retrospective review was conducted on all the cases of Schatzker types V and VI tibial plateau fractures treated by Ilizarov external fixation between July 2006 and December 2015 with the minimum follow-up duration of one year. There were 30 patients: 24 males and 6 females, mean age 43.33 years, and mean follow-up 3.6 years. Three of them were open fractures; 15 cases were Schatzkertype V fractures and the other 15 type VI. According to AO/OTA classification, there were 11 type C1, 12 C2 and 7 type C3 fractures. Outcome assessment was made with American Knee Society Score (AKSS) and Rasmussen's Radiological Score (RRS) at final follow-up. Results: Out of the 30 cases, mini-open reduction was performed in 7, bone graft in 4, minimal internal fixation in 10 and knee temporary immobilisation in 11 patients. Mean duration of external fixation was 11.8 weeks. All fractures united. Pin tract infections in 7 and common peroneal neuropathy in 2 patients were self-limiting. Two patients had axial misalignment of less than 10°. At final follow-up, the mean knee range of motion was 114.7, mean AKSS 81.5 and mean RRS 16.7. On statistical analysis, Schatzker type of fractures, use of minimal internal fixation and knee-spanning did not influence the final outcome. Conclusion: Ilizarov external fixator with or without minimal internal fixation provides acceptable outcome for complex tibial plateau fractures. Care must be taken to look for minor loss of alignment, especially in Type VI Schatzker fractures after removal of the fixator. However small sample size precludes firm conclusions. Keywords: Tibial plateau fractures, Schatzker's classification, Ilizarov techniques, Ring fixato

Guidelines for safe bilateral tibial lengthening for stature

Context: Limb lengthening has its own share of problems, obstacles, and complications, which is of great concern when used for a cosmetic indication. Aims: This study explores safe limits for cosmetic tibial lengthening and examines how age of the patient and length gained influences osteogenesis and complications. Settings and Design: This was a retrospective analytical study. Subjects and Methods: We reviewed 70 consecutive cases (140 segments) of monofocal tibial cosmetic lengthening with minimum of 1-year follow-up operated between 2006 and 2010. Statistical Analysis Used: We correlated patient's age and percentage by which bone was lengthened with external fixator index (EFI) and occurrence of obstacles and complications and did receiver operator characteristic (ROC) curve analysis to determine the safe limit. Results: Mean age of patients was 27 (16–52) years. Mean tibial lengthening was by 16.5% (4.1–27.9) of the preoperative length. Sixty segments faced 76 difficulties comprising 16 problems, 47 obstacles, and 13 complications. Patient's age positively correlated with EFI, but did not correlate with the incidence of obstacles and complications. Percentage by which bone was lengthened negatively correlated with EFI and positively correlated with incidence of obstacles and complications. ROC curve analyses (with optimum balance of sensitivity and specificity) revealed lengthening by more than 18.1% and 16.4% to be significantly associated with the occurrence of complication and more than one obstacle, respectively. Conclusions: In cosmetic tibial lengthening, increasing age increases the duration of external fixation and increased lengthening increases obstacles and complications. Great caution must be exercised in cosmetic tibial lengthening beyond 16%

Enhanced Optical Management in Organic Solar Cells by Virtue of Square-Lattice Triple Core-Shell Nanostructures

This research focuses on enhancing the optical efficacy of organic photovoltaic cells, specifically their optical absorbance and electrical parameters. The absorbance of photons in organic solar cells (OSCs) was studied by incorporating an optical space layer and triple core-shell square-lattice nanostructures. For better chemical and thermal stability, a dielectric-metal-dielectric nanoparticle can be replaced for embedded metallic nanoparticles in the absorption layer. The 3D (finite-difference time-domain) FDTD method was used to analyze the absorption and field distribution in OSCs using 3D model morphology. Firstly, an optimization of thickness of the optical spacer layer was analyzed and secondly, the impact of adding triple core-shell nanostructures at different levels of an OSC were studied. The photovoltaic properties such as short circuit current density, power conversion efficiency, fill factor, Voc were investigated. The proposed design has demonstrated an improvement of up to 80% in the absorption of light radiation in the photoactive region (donor or acceptor) of OSCs in the wavelength range of 400 nm to 900 nm when compared with that of nanostructures proposed at various layers of OSC

Sonographic evaluation of distraction osteogenesis in patients undergoing lengthening of tibia for increase in stature

Context: Limb lengthening demands constant monitoring of the regenerate bone by frequent radiological examinations. Aims: The aim of the study was to explore if sonography can be used in place of radiography for monitoring distraction osteogenesis. Settings and Design: This study was a prospective and observational study. Subjects and Methods: Thirty-five consecutive patients with a mean age of 24, where tibia was monofocally lengthened by mean of 5.5 cm ± 0.5 cm were included in the study. Along with all radiological assessments (every 2 weeks during Distraction Phase [DP] and 4 weeks during Maturation Phase [MP]), concurrent sonographic assessment was done and findings compared. Statistical Analysis Used: Descriptive methods. Results: Reparative granulation tissue in the distraction gap and endosteal reaction at both ends were visualized sonographically at 2 weeks before any radiological evidence of regeneration. The echolucent gap increased as distraction progressed with the internal hyperechoic signals getting organized to linear structures at 4 weeks when first radiological evidence was noted. This echopositive portion of the regenerate bone narrowed down by 6−8 weeks when radiographs showed bony trabeculae, more so in MP. By 14−16 weeks of MP, there was a significant reduction of echopositive zone, where more of regenerate got converted to hyperechogenic cortical bone. Sonography was poor in measuring distraction gap and assessing mechanical axis alignment. Sonographic findings correlated well with the findings of accelerated and poor regeneration on radiographs during DP and aided modification of distraction. Conclusions: Sonography is a valuable tool in DP and first half of MP and many radiographic examinations during these phases may be replaced by sonography. Judicious and combined application of sonography and radiography must be explored for superior characterization and monitoring during limb lengthening, with lesser radiation exposure

4-Aminoquinolone Piperidine Amides: Noncovalent Inhibitors of DprE1 with Long Residence Time and Potent Antimycobacterial Activity

4-Aminoquinolone piperidine amides (AQs) were identified as a novel scaffold starting from a whole cell screen, with potent cidality on Mycobacterium tuberculosis (Mtb). Evaluation of the minimum inhibitory concentrations, followed by whole genome sequencing of mutants raised against AQs, identified decaprenylphosphoryl-beta-D-ribose 2'-epimerase (DprE1) as the primary target responsible for the antitubercular activity. Mass spectrometry and enzyme kinetic studies indicated that AQs are noncovalent, reversible inhibitors of DprE1 with slow on rates and long residence times of similar to 100 min on the enzyme. In general, AQs have excellent leadlike properties and good in vitro secondary pharmacology profile. Although the scaffold started off as a single active compound with moderate potency from the whole cell screen, structure-activity relationship optimization of the scaffold led to compounds with potent DprE1 inhibition (IC50 < 10 nM) along with potent cellular activity (MIC = 60 nM) against Mtb

4‑Aminoquinolone Piperidine Amides: Noncovalent Inhibitors of DprE1 with Long Residence Time and Potent Antimycobacterial Activity

4-Aminoquinolone piperidine amides (AQs) were identified as a novel scaffold starting from a whole cell screen, with potent cidality on Mycobacterium tuberculosis (Mtb). Evaluation of the minimum inhibitory concentrations, followed by whole genome sequencing of mutants raised against AQs, identified decaprenylphosphoryl-β-d-ribose 2′-epimerase (DprE1) as the primary target responsible for the antitubercular activity. Mass spectrometry and enzyme kinetic studies indicated that AQs are noncovalent, reversible inhibitors of DprE1 with slow on rates and long residence times of ∼100 min on the enzyme. In general, AQs have excellent leadlike properties and good in vitro secondary pharmacology profile. Although the scaffold started off as a single active compound with moderate potency from the whole cell screen, structure–activity relationship optimization of the scaffold led to compounds with potent DprE1 inhibition (IC₅₀ < 10 nM) along with potent cellular activity (MIC = 60 nM) against Mtb