PURPOSE OF THE STUDY The paper presents a monocentric retrospective study of patients treated surgically for spinal tuberculosis. Clinical and radiological results are analysed, early and late ...complications are recorded. The study aims to answer the following questions. 1. Can we use instrumentation to restore the stability and alignment in the infected spinal focus? 2. Should we always perform radical anterior resection of TBC lesions? 3. What is the prognosis of surgical treatment of TBC patients with neurological deficit manifestation? MATERIAL AND METHODS Between 2010 and 2020, a total of 12 patients were treated for spinal tuberculosis at our department, of whom 9 patients (5 men, 4 women) with the mean age of 47.3 years (range 29 to 83 years) underwent a surgery. A total of three patients were operated on before the final confirmation of the TBC and treatment with antituberculosis medication, four patients in the initial therapy phase and two patients in the continuous phase. Two patients only underwent a non-instrumented decompression surgery followed by external support fixation. In the other seven patients, always with spinal deformity, instrumentation was used (3 cases of isolated posterior decompression, transpedicular fixation, posterior fusion, 4 cases of anteroposterior instrumented reconstruction). In 2 cases a structural bone graft and in 2 cases an expandable titanium cage were used for anterior column reconstruction. RESULTS Of the total number of patients, altogether eight patients were assessed at 1 year after surgery (one 83-year-old patient died from heart failure 4 months after surgery). Of the remaining eight patients, three patients exhibited a neurological deficit and postoperative regression of the finding. The McCormick score improved from the preoperative mean score of 3.25 to 1.62 at 1 year after surgery (p < 0.001). The clinical VAS score regressed from 5.75 to 1.63 at 1 year after surgery (p < 0.001). Radiographic healing of the anterior fusion was achieved in all patients, both after decompression and instrumented surgery. The initial mean kyphosis of 20.36 degrees of the operated segment measured by the mCobb angle was corrected to 14.6 degrees postoperatively, with a subsequent slight deterioration to 14.86 degrees (p < 0.05). The greatest correction was achieved in patients who had undergone a two-stage surgery with anterior resection and AP reconstruction. DISCUSSION In our cohort, titanium instrumentation was used in seven of nine patients. One patient only manifested persistent tuberculosis with nonspecific bacterial flora superinfection. Revision surgery with anterior radical debridement and subsequent treatment with antituberculotic drugs healed the patient. There were four patients with major preoperative neurological deficit persisting more than 2 weeks before the final treatment with subsequent improvement in all cases. These patients were treated with anteroposterior reconstruction and anterior radical debridement. CONCLUSIONS No increased risk of recurrent infection associated with the use of spinal instrumentation was found in the study. Anterior radical debridement is performed in patients with manifested kyphotic deformity and spinal canal compression, followed by reconstruction with a structural bone graft or a titanium cage. The other patients are treated based on the principle of "optimal" debridement with or without the use of transpedicular instrumentation. If adequate spinal canal decompression and stability are achieved, neurological improvement can be anticipated even in case of a major neurological deficit. Key words: spine tuberculosis, tuberculous spondylitis, Pott's disease, anterior debridement, spine instrumentation.
Surgical Treatment of Cervical Spondylodiscitis Včelák, J; Špeldová, A; Džupová, O ...
Acta chirurgiae orthopaedicae et traumatologiae Čechoslovaca,
12/2021, Letnik:
88, Številka:
6
Journal Article
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PURPOSE OF THE STUDY The purpose of the retrospective study is to analyse a group of patients surgically treated for cervical spondylodiscitis. The first hypothesis states that the removal of ...infected intervertebral disc without its anterior column reconstruction in the acute phase of infection results in worse clinical and radiological evaluation of the patient. The second hypothesis defines that the use of titanium implant in anterior column reconstruction in the chronic phase of infection increases the risk of recurrent infection. MATERIAL AND METHODS The evaluated group of patients who underwent surgery includes a total of 21 patients (8 females, 13 males) with the mean age of 57.6 years. 12 patients in the acute phase of infection were treated by anterior debridement without disc space reconstruction, of whom four patients were completed by posterior instrumented fusion in the second stage. In 9 patients in the chronic phase of infection radical anterior debridement was completed by anterior titanium implant reconstruction, of whom in five patients posterior instrumented fusion was performed in the second stage. All patients were clinically evaluated by mJOA, VAS and Frankel score preoperatively, at 6 months and at 1 year postoperatively. The radiologic evaluation assessed the instrumentation failure, spinal fusion and kyphosis progression measured by sagittal Cobb angle. RESULTS The mJOA values improved from the mean preoperative value of 1.6 to 13.15 (6M) and 13.3 (1Y) postoperatively (p = 0.055). The VAS score increased from the mean value of 8.5 preoperatively to 2.15 (6M) and 1.35 (1Y) postoperatively (p < 0.001). No patient reported worse neurological finding postoperatively. The kyphosis progression measured by sagittal Cobb angle from the preoperative +6.7 decreased to +3.2 degrees at 1 year after surgery. The group of 12 patients treated in the acute phase of infection by anterior debridement without anterior column reconstruction showed worsening of kyphosis from +1.1 before surgery to +1.6 degrees at 1 year after surgery. The group of eight patients treated in the chronic phase by anterior debridement and reconstruction of the anterior column by implant changed from +15.9 before surgery to +6.1 degrees at 1 year after surgery. In two out of 12 patients with neurological deficit, the T2-weighted MRI finding of signal hyperintensity showed no improvement of the neurological deficit. DISCUSSION In the group of all operated patients, neither the worsening in the clinical evaluation using the mJOA or VAS score, nor kyphosis progression measured by Cobb angle in the sagittal plane, or failure of instrumentation in the anteroposterior procedure were reported postoperatively. In a total of nine patients operated on during the chronic phase of infection, in whom titanium implant was used to reconstruct the anterior column defect, no recurrent deep infection was observed. CONCLUSIONS In the acute phase we prefer anterior debridement with epidural abscess evacuation without anterior column reconstruction and posterior instrumented fusion in case of kyphosis progression in the second stage. In the chronic phase, radical anterior debridement with titanium implant reconstruction, eventually with posterior instrumented fusion is preferred. Key words: cervical spondylodiscitis, epidural abscess, anterior debridement, bacterial biofilm.
In this paper, we present the design and characterization of a novel ankle robot developed at the Massachusetts institute of technology (MIT). This robotic module is being tested with stroke patients ...at Baltimore Veterans administration medical center. The purpose of the on-going study is to train stroke survivors to overcome common foot drop and balance problems in order to improve their ambulatory performance. Its design follows the same guidelines of our upper extremity designs, i.e., it is a low friction, backdriveable device with intrinsically low mechanical impedance. Here, we report on the design and mechanical characteristics of the robot. We also present data to demonstrate the potential of this device as an efficient clinical measurement tool to estimate intrinsic ankle properties. Given the importance of the ankle during locomotion, an accurate estimate of ankle stiffness would be a valuable asset for locomotor rehabilitation. Our initial ankle stiffness estimates compare favorably with previously published work, indicating that our method may serve as an accurate clinical measurement tool.
Hemiparesis after stroke often leads to impaired ankle motor control that impacts gait function. In recent studies, robotic devices have been developed to address this impairment. While capable of ...imparting forces to assist during training and gait, these devices add mass to the paretic leg which might encumber patients' gait pattern. The purpose of this study was to assess the effects of the added mass of one of these robots, the MIT's Anklebot, while unpowered, on gait of chronic stroke survivors during overground and treadmill walking.
Nine chronic stroke survivors walked overground and on a treadmill with and without the anklebot mounted on the paretic leg. Gait parameters, interlimb symmetry, and joint kinematics were collected for the four conditions. Repeated-measures analysis of variance (ANOVA) tests were conducted to examine for possible differences across four conditions for the paretic and nonparetic leg.
The added inertia and friction of the unpowered anklebot had no statistically significant effect on spatio-temporal parameters of gait, including paretic and nonparetic step time and stance percentage, in both overground and treadmill conditions. Noteworthy, interlimb symmetry as characterized by relative stance duration was greater on the treadmill than overground regardless of loading conditions. The presence of the unpowered robot loading reduced the nonparetic knee peak flexion on the treadmill and paretic peak dorsiflexion overground (p < 0.05).
Our results suggest that for these subjects the added inertia and friction of this backdriveable robot did not significantly alter their gait pattern.
Tritium is released abundantly to the environment by nuclear power plants (NPP), as a product of neutron capture by hydrogen and deuterium. In normal running conditions, released cooling waters may ...contain levels of tritium close to or even larger than the maximum authorised limit for human consumption (drinking and irrigation). The European Council Directive 2013/51/Euratom requires a maximum level of tritium in water for human consumption lower than 100 Bq=L. Current monitoring of tritium activity in water by liquid scintillating method takes about two days and can only be carried out in a dedicated laboratory. This system is not appropriate for real time monitoring. At present, there exists no available detector device with enough sensitivity to monitor waters for human consumption with high enough sensitivity. The goal of the TRITIUM project is to build a tritium monitor capable to measure tritium activities with detection limit close to 100Bq=L, using instrumentation technique developed in recent years for Nuclear and Particle Physics, such as scintillating fibres and silicon photomultipliers (SiPM). In this paper the current status of the TRITIUM project is presented and he results of first prototypes are discussed. A detector system based on scintillating fibers read out either photomultiplier tubes (PMTs) or silicon photomultiplier (SiPM) arrays is under development and will be installed in the vicinity of Almaraz nuclear power plant (Cáceres, Spain) by the fourth term of 2019.
3D technology implementation in medicine Macko, M; Szczepański, Z; Mikołajewski, D ...
IOP conference series. Materials Science and Engineering,
02/2020, Letnik:
776, Številka:
1
Journal Article
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New modern additive technologies and reverse engineering are becoming available, especially in medical applications. The paper presents possible ways of using additive technologies in the scope of ...increasing the level of training of medical specialists in everyday clinical practice and in the selection of the appropriate scenario before real surgery. Descriptions of projects implemented with surgeons whose effect is to achieve aforementioned goals have been presented. The concepts are known as new solutions, but their further development may lead to the extension of the scope of application of these techniques in medicine, among others in relation to other disciplines.
PURPOSE OF THE STUDY The purpose of the study is a retrospective comparison of results of the two-stage revision total hip arthroplasty using a non-articulating and an articulating spacer to treat ...periprosthetic joint infection (PJI). Two basic hypotheses are evaluated: (1) the clinical outcomes of the patients treated with "hand made" articulating cement spacer are better than in non-articulating patient's group in two-stage revision for PJI of the total hip arthroplasty and (2) PJI recurrence is higher in the group of patients treated with an articulating spacer group. MATERIAL AND METHODS The evaluated group consists of a total of 57 patients (23 women, 34 men) with the mean age of 61.2 years. Group A of 39 patients were treated by two-stage revision using the "hand-made" articulating cement spacer and Group B of 18 patients were treated using the non-articulating spacer. Both the groups were evaluated retrospectively in the reference period: preoperatively and two years after the surgery using the Harris Hip Score (HHS) clinical assessment. The revision surgery for acute and chronic complications of treatment, length of hospitalization, and the PJI recurrence were evaluated for both the groups. RESULTS The resulting HHS clinical reviews were pre-operatively 43.59 points in both the groups with postoperative improvement up to 81.74 points. The mean preoperative HHS scores were 41.67 points (Group A) and 47.77 points (Group B) and two years after the surgery they were 83.43 points (Group A) and 78.08 points (Group B) (two-tailed t-test, p-value = 0.042). In Group A a total of seven revisions were performed in the interval between the two-stage revision (4x recurrent dislocation, 2x persistent infection, 1x spacer fracture). In Group B one patient was revised for persistent infection. In the two-year period after the operation, a relapse of PJI was recorded in 5 patients in Group A (12.8%) and in 1 patient in Group B (5.6%) (Chi-square test, p-value = 0.41). The average time of hospitalization was 51.58 days, whereby 49.72 days and 55.61 days on average for Group A and B respectively (p-value = 0.53). DISCUSSION According to recent studies, the advantage of motion preservation in articulating cement spacers can be complicated by recurrent dislocations, implant migration, periprosthetic fractures or recurrent joint replacement infections, which can further prolong the treatment and worsen the final clinical results. An alternative treatment option is the application of a nonarticulating spacer maintaining the advantage of local administration of antibiotics and reducing the dead space formed by the infected implant removal. Discussed is mainly the choice of the method in case of muscle disorder or presence of segmental bone defects. CONCLUSIONS The results demonstrate the better clinical outcomes and the higher revision rate of patients with an articulating cement spacer in two stage revision. We didn't find any differences between the risk of PJI recurrence in both groups. Key words:periprosthetic infection, total hip replacement, cement spacer, two stage revision, articulating spacer, nonarticulating spacer.
Abstract
This paper presents the results of research on the process of grinding dried corn stalks to use them as polylactide filler. Shredding was carried out on a laboratory shredder with the use of ...a design variant based on discs with cylindrical holes. By selecting the design variant, the appropriate grinding speed and the material pressure on the shredder discs, the most favourable parameters in terms of the quality of the shredded product and low energy consumption were selected. The research was conducted to reduce the energy demand during the shredding process and to obtain the shredded material suitable for further processing steps.
Abstract
The paper presents a comparative analysis of the effect of selected design features of blade and disc units on the functional characteristics of the process of grinding corn stalks in ...specific ranges of input variables. The effect of changes in the geometric features of the working units and rotational speeds on the energy demand during the grinding process was estimated. On this basis, an assessment of the quality of the shredding product in terms of shape and size was also made.
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