Clinical and neuropathological study about the neurotization of the suprascapular nerve in obstetric brachial plexus lesions

<p>Abstract</p> <p>Background</p> <p>The lack of recovery of active external rotation of the shoulder is an important problem in children suffering from brachial plexus lesions involving the suprascapular nerve. The accessory nerve neurotization to the suprascapular nerve is a standard procedure, performed to improve shoulder motion in patients with brachial plexus palsy.</p> <p>Methods</p> <p>We operated on 65 patients with obstetric brachial plexus palsy (OBPP), aged 5-35 months (average: 19 months). We assessed the recovery of passive and active external rotation with the arm in abduction and in adduction. We also looked at the influence of the restoration of the muscular balance between the internal and the external rotators on the development of a gleno-humeral joint dysplasia. Intraoperatively, suprascapular nerve samples were taken from 13 patients and were analyzed histologically.</p> <p>Results</p> <p>Most patients (71.5%) showed good recovery of the active external rotation in abduction (60°-90°). Better results were obtained for the external rotation with the arm in abduction compared to adduction, and for patients having only undergone the neurotization procedure compared to patients having had complete plexus reconstruction. The neurotization operation has a positive influence on the glenohumeral joint: 7 patients with clinical signs of dysplasia before the reconstructive operation did not show any sign of dysplasia in the postoperative follow-up.</p> <p>Conclusion</p> <p>The neurotization procedure helps to recover the active external rotation in the shoulder joint and has a good prevention influence on the dysplasia in our sample. The nerve quality measured using histopathology also seems to have a positive impact on the clinical results.</p

Inverse Estimation of Temperature Profiles in Landfills Using Heat Recovery Fluids Measurements

In addition to leachate and gas emission analysis, temperature variations in municipal solid waste landfills are routinely monitored for safety and health reasons, such as the increased production of biogas or the danger of spontaneous combustion phenomena if the temperature exceeds 70–75°C. The increasing constraints on greenhouse gas emissions and the convenience of fuel and heat recovery have helped develop a global approach to landfills' operation and maintenance, generally referred to as bioreactor landfill management. The heat recovery piping we are presently designing can be a significant part of this approach. The heat gained by a fluid circulated in a closed network through the landfill is transferred to an external heat exchanger or used directly as warm water. Additionally, it can help reduce landfill temperature levels and control biogas generation. Since the pipes diameter is large enough to allow for a radial temperature gradient, this information can be used for an inverse estimation of the temperature profile in the landfill which constitutes the boundary conditions of the resulting heat transfer problem. In this paper, we describe an algorithm for regularising the resulting ill-posed free boundary estimation problem using sampled data of the heat recovery fluid on exiting the landfill

NON-INVASIVE INVERSE PROBLEM IN CIVIL ENGINEERING

In this contribution we focus on recovery of spatial distribution of material parameters utilizing only non-invasive boundary measurements. Such methods has gained its importance as imaging techniques in medicine, geophysics or archaeology. We apply similar principles for non-stationary heat transfer in civil engineering. In oppose to standard technique which rely on external loading devices, we assume the natural fluctuation of temperature throughout day and night can provide sufficient information to recover the underlying material parameters. The inverse problem was solved by a modified regularised Gauss-Newton iterative scheme and the underlying forward problem is solved with a finite element space-time discretisation. We show a successful reconstruction of material parameters on a synthetic example with real measurements. The virtual experiment also reveals the insensitivity to practical precision of sensor measurements