Complications common in motorized intramedullary bone transport for non-infected segmental defects: a retrospective review of 15 patients

Background and purpose — Since the introduction of intramedullary bone transport nails only very few cases have been reported in the literature. Thus we evaluated the results and complications in a single institution retrospective cohort.Patients and methods — 15 (median age 40 years (18-70), 8 males) consecutive patients, were included and the electronic patient records and radiographs were reviewed. Complications were severity graded and categorized as device or non-device related.Results — The segmental bone loss was due to non-union site in 8 femurs and 4 tibias, or traumatic bone loss in 2 femurs and 1 tibia. The segmental bone defect was a median of 3 cm (0.5–10). 9 of 10 femoral cases and 4 of 5 tibial cases healed with the bone transport nail. All 15 patients had a healed docking site and regenerate at the end of treatment after a median of 13 months (6–38). 24 complications (15 device related and 9 non-device related) occurred in 11/15 patients with a minimum follow-up of 6 months after nail removal. The number of unplanned surgeries due to device related complications was: 0 in 9 patients, 1 in 3 patients, 2 in 1 patient, 3 in 2 patients.Interpretation — Segmental bone defects can heal with a bone transport nail. However, the number of complications was high and 15 out of 24 complications were devicerelated. Optimizing nail design is therefore needed to reduce complications in intramedullary bone transport.

The concept of intramedullary bone transport nails to treat lower limb segmental bone defects was introduced by Baumgart et al. (1997) and refined by Kold and Christensen (2014) to alleviate the known complications seen in bone transport by external fixation (Paley and Maar 2000). The assumed advantages of using a fully implantable bone transport nail compared with external fixation is that early full joint motion is facilitated as skin and muscles are not transfixated, patient discomfort is reduced, pin site infections are eradicated, and the nail can be left in situ until the callus is sufficiently hardened. This potentially reduces the risk of fracture and secondary deformity as seen after removal of external fixators (Liu et al. 2020). However, only 5 cases of intramedullary bone transport nails have been reported (Baumgart et al. 1997, Kold and Christensen 2014, Accadbled et al. 2019), and a recent systematic review has showed high complication rates in bone lengthening despite the use of externally controlled motorized bone lengthening nails (Frost et al. 2020). Therefore, there is a need to investigate assumed advantages of the internal bone transport technique and observe if other complications are introduced by this new technique. We report our experience with the FITBONE bone transport nail in 15 patients with a minimum of 6 months’ follow-up after nail removal. We posed 2 questions: Are the bone transport nails capable of obtaining bone healing? Have new complications been introduced by the motorized transport nail?     

Decreased plasminogen activator inhibitor and tissue metalloproteinase inhibitor expression may promote increased metalloproteinase activity with increasing duration of human atrial fibrillation

Introduction: Atrial fibrosis has been shown to concur with the persistence of atrial fibrillation (AF) and is only incompletely reversible, thus counteracting attempts to restore and maintain sinus rhythm (SR). Besides the angiotensin system, the matrix metalloproteinases (MMP) play a major role in the pathogenesis of fibrosis. Thus, the present study investigated changes of the MMP system during the development of human AF.
Methods and Results: Right atrial appendages of 146 patients were excised during heart surgery and grouped according to rhythm (SR vs AF) and AF duration. Hydroxyproline as a surrogate for collagen content and morphometrically determined collagen content increased significantly from SR (14.3 ± 7.7%) to chronic permanent AF (CAF) of 6–24 months (21.2 ± 9.2%, P = 0.02), and CAF of > 60 months (25.3 ± 4.7%, P < 0.01). From SR to paroxysmal and chronic persistent AF (CPAF) and to CAF MMP-2 and MMP-9 activity rose, while their mRNA and protein levels were not altered significantly. Plasminogen activator inhibitor (PAI), an inhibitor of a potent activator of many MMPs, was significantly decreased with increasing duration of AF. In parallel, the mRNA levels of the tissue inhibitors of MMPs TIMP-1 and -2 decreased significantly.
Conclusion: Human atrial fibrogenesis is enhanced with increasing duration of AF: a longer AF duration is associated with elevated atrial interstitial MMP activity, but decreased PAI and TIMP expression.     

Malignancies after kidney transplantation: 3 clinical case reports

Post-transplant malignancies present an aggressive course and are a significant cause of morbidity and mortality. Tumours of viral ethiology have the greatest risk in renal transplant recipients. Oncogenic effect of immunosuppressive therapy is another major risk factor of post-transplant malignancy. We report cases of three different types of malignancies developed after kidney transplantation: non-Hodgkin’s lymphoma, Kaposi’s sarcoma and germ cell testicular cancer (nonseminoma).     

Surgical treatment of non-malignant laryngotracheal stenosis

The objectives of this study were the following: (1) to analyze the results of surgical treatment of non-malignant subglottic laryngeal and tracheal stenosis, (2) to evaluate the feasibility and technical aspects of the video mediastinoscopy for the mobilization of the mediastinal trachea, (3) to evaluate the influence of the early internal condition of the anastomosis on the development of restenosis. From 1996 up to 2013, 75 patients aged 11–78 years underwent surgery for post-intubation/tracheostomy (71 patients), post-traumatic (3 patients), and idiopathic (1 patient) subglottic laryngeal and tracheal stenosis. Twenty-three (30.7 %) patients with subglottic laryngeal and upper tracheal stenosis underwent cricotracheal resection and thyrotracheal anastomosis (group A), while 52 (69.3 %) patients with tracheal stenosis underwent tracheal resection and cricotracheal or tracheotracheal anastomosis (group B). The length of the resected segment in patients of groups A and B was 28–55 (42 ± 11) mm and 18–65 (36 ± 14) mm, respectively, (p = 0.22). Perioperative complications within 30 days occurred in eight (34.8 %) patients of group A, and in six (11.5 %) patients of group B (p = 0.04). There was one intraoperative and one postoperative death on the third day due to heart failure. The excellent results were achieved in 63 (86.3 %), satisfactory in 8 (11.0 %), and unsatisfactory in 2 (2.7 %) patients. The incidence rate of perioperative complications is related to the location of the stenosis and the type of the resection and anastomosis. Video mediastinoscopy simplifies the mobilization of the mediastinal trachea, which allows for carrying out the anastomosis with minimal tension. Early internal abnormalities of the anastomosis predict its restenosis.     

Reactive Oxygen Species in Peripheral Blood and Sputum Neutrophils During Bacterial and Nonbacterial Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Chronic airway inflammation can be mediated by an enhanced neutrophil oxidative burst. However, the role of bacteria in the pathogenesis of chronic obstructive pulmonary disease (COPD) exacerbations is highly controversial. The aim of this study was to evaluate the production of reactive oxygen species (ROS) in peripheral blood and sputum neutrophils during bacterial and nonbacterial acute exacerbations of COPD (AECOPD). A total of 40 patients with AECOPD, 10 healthy nonsmokers, and 10 “healthy” smokers were enrolled into the study. Peripheral blood and sputum samples were obtained during exacerbation and after recovery. Neutrophils were isolated by high-density gradient centrifugation and magnetic separation. ROS production by neutrophils was investigated after stimulation with phorbol-myristate-acetate and Staphylococcus aureus bacteria. ROS production by neutrophils was assessed as the mean fluorescent intensity using a flow cytometer. IL-8 levels in serum and induced sputum were determinant by ELISA. Spontaneous ROS production was significantly higher in neutrophils from the patients with bacterial AECOPD as compared with nonbacterial AECOPD and stable COPD (P <0.05). ROS production stimulated with PMA and with Staphylococcus aureus was significantly higher in neutrophils isolated from the patients with bacterial AECOPD as compared with nonbacterial and stable COPD (P <0.05). The serum and induced sputum IL-8 levels were significantly increased in the patients with bacterial AECOPD than nonbacterial AECOPD, stable COPS, and “healthy” smokers and nonsmokers (P <0.05) and higher in the induced sputum as the compared with serum in all studied groups (P <0.05). Enlarge CRP level was documented during AECOPD than in all other groups (P <0.05). A markedly increased ROS production in sputum neutrophils during bacterial AECOPD shows an inflammatory response reflecting enhanced local inflammation, which can be mediated by bacterial colonization.     

Successful use of extracorporeal membrane oxygenation in a human immunodeficiency virus infected patient with severe acute respiratory distress syndrome

Introduction

We report a case of an adult patient with human immunodeficiency virus (HIV), acute respiratory distress syndrome (ARDS) and ventilator associated pneumonia (VAP) caused by multidrug resistant (MDR) bacteria that was successfully managed with veno-venous extracorporeal membrane oxygenation (ECMO).

Case report

A 25 year old male with no significant past medical history had been admitted to a local hospital due to dyspnea and fever. His pulmonary function subsequently failed necessitating mechanical ventilation (MV) and introduction of ECMO support. The patient was transported for 300 km by road on ECMO to a tertiary medical center. The diagnosis of ARDS, HIV infection and MDR bacterial and fungal VAP was made. Patient was successfully treated with antiretroviral therapy (ART), anti-infective agents and 58 days of veno-venous ECMO support, with complete resolution of the respiratory symptoms.

Conclusion

HIV infected patients with ARDS and MDR bacterial VAP whose HIV replication is controlled by ART could be successfully managed with ECMO.