19 research outputs found
The anatomy of the medial collateral ligament of the knee and its significance in joint stability
The medial collateral ligament (MCL) is the most important stabilizer of the medial side of the knee together with the capsuloligamentous complex. As such, it has a distinctive role in joint stability, as far as its biomechanics are concerned, and major joint stability issues onset when it is injured or deficient. One of the main functions of the medial collateral ligament is mechanical as it passively stabilizes the knee and help in guiding it through its normal range of motion when a tensile load is applied. It exhibits nonlinear anisotropic mechanical behaviour, like all ligaments, and under low loading conditions it is relatively compliant, perhaps due to recruitment of “crimped” collagen fibres as well as to viscoelastic behaviours and interactions of collagen and other matrix materials. Continued ligament-loading results in increasing stiffness until a stage is reached where it exhibits nearly linear stiffness and beyond this it continues to absorb energy until it is disrupted. In addition, the function of the MCL has to do with its viscoelasticity which assists the maintainance of joint congruity and homeostasis. The treatment of grade III medial collateral ligament injuries (with gross valgus instability at 0° of flexion) is still controversial. The most severe injuries (especially with severe valgus alignment, intra-articular medial collateral ligament entrapment, large bony avulsions, or multiple ligament involvement) may require acute operative repair or augmentation. In addition, surgical reconstruction is indicated for isolated symptomatic chronic medial collateral ligament laxity. The optimal surgical treatment remains controversial. More studies with evidence of level I and II are required in order to clarify the pros and cons of any solution
The statistical analysis plan for the unification of treatments and interventions for tinnitus patients randomized clinical trial (UNITI-RCT)
Background
Tinnitus is a leading cause of disease burden globally. Several therapeutic strategies are recommended in guidelines for the reduction of tinnitus distress; however, little is known about the potentially increased effectiveness of a combination of treatments and personalized treatments for each tinnitus patient.
Methods
Within the Unification of Treatments and Interventions for Tinnitus Patients project, a multicenter, randomized clinical trial is conducted with the aim to compare the effectiveness of single treatments and combined treatments on tinnitus distress (UNITI-RCT). Five different tinnitus centers across Europe aim to treat chronic tinnitus patients with either cognitive behavioral therapy, sound therapy, structured counseling, or hearing aids alone, or with a combination of two of these treatments, resulting in four treatment arms with single treatment and six treatment arms with combinational treatment. This statistical analysis plan describes the statistical methods to be deployed in the UNITI-RCT.
Discussion
The UNITI-RCT trial will provide important evidence about whether a combination of treatments is superior to a single treatment alone in the management of chronic tinnitus patients. This pre-specified statistical analysis plan details the methodology for the analysis of the UNITI trial results.
Trial registration
ClinicalTrials.gov NCT04663828. The trial is ongoing. Date of registration: December 11, 2020. All patients that finished their treatment before 19 December 2022 are included in the main RCT analysis
Heat-exchanger design and switching-frequency effects on the performance of a continuous type solar adsorption chiller
A transient one-dimensional model, capable of describing the performance of a newly-introduced adsorption chiller with continuous operation, is developed. Since the cycle time and the switching frequency have a great influence on chiller performance, a non-dimensional switching frequency is introduced and a systematic parametric study is carried out in order to determine regions of optimal operation. An optimization based on the thermodynamic efficiency yields a lower switching frequency than an optimization based on the maximum cooling capacity. In addition, the effect of the heat-exchanger design parameters on system performance is explored. An increase of either the bed's Fourier number or the thermofluid's Nusselt number has a positive effect on both COP and cooling capacity. An improvement of system performance can also be achieved by decreasing either the thermofluid's Fourier number or the bed's Biot number. Finally, the effect of space velocity of the thermofluid exhibits the most interesting behavior; an increase of the space velocity has a positive effect on cooling capacity and a negative effect on COP.Solar adsorption chiller Solar air-conditioning Switching frequency Dimensionless numbers Heat exchanger Silica gel
Hearing Aid Fitting in Tinnitus: A Scoping Review of Methodological Aspects and Effect on Tinnitus Distress and Perception
Current evidence on efficacy of hearing aids (HAs) on tinnitus perception and annoyance is considered insufficient due to the heterogeneity of tinnitus characteristics and of methods used in the relevant clinical studies. This is a scoping review focused on the methodological aspects of clinical studies evaluating the value of HA fitting as part of tinnitus management over the past 10 years. Thirty-four studies were included in the review, showing important heterogeneity in almost all aspects of inclusion criteria, comparators, outcome measures, follow-up time and HA fitting procedures. Although all studies show that HA fitting has a positive impact on tinnitus perception in patients with hearing loss, the methodological heterogeneity does not allow robust conclusions. Future studies taking into account the different nature and goals of each tinnitus therapeutic modality and adapting their methods, endpoints and timelines according to them could lay the groundwork for obtaining high-quality evidence on whether and how HA fitting shall be implemented in tinnitus management strategies
Hearing Aid Fitting in Tinnitus: A Scoping Review of Methodological Aspects and Effect on Tinnitus Distress and Perception
Current evidence on efficacy of hearing aids (HAs) on tinnitus perception and annoyance is considered insufficient due to the heterogeneity of tinnitus characteristics and of methods used in the relevant clinical studies. This is a scoping review focused on the methodological aspects of clinical studies evaluating the value of HA fitting as part of tinnitus management over the past 10 years. Thirty-four studies were included in the review, showing important heterogeneity in almost all aspects of inclusion criteria, comparators, outcome measures, follow-up time and HA fitting procedures. Although all studies show that HA fitting has a positive impact on tinnitus perception in patients with hearing loss, the methodological heterogeneity does not allow robust conclusions. Future studies taking into account the different nature and goals of each tinnitus therapeutic modality and adapting their methods, endpoints and timelines according to them could lay the groundwork for obtaining high-quality evidence on whether and how HA fitting shall be implemented in tinnitus management strategies
Nicholas J. Giannestras (1908-1978): a distinguished orthopaedic surgeon, his work, life and times
The purpose of our study was to summarize all the knowledge concerning
the innovative pioneer in the field of orthopaedic surgery, Nicholas J.
Giannestras (1908-1978). A thorough study of texts, medical books and
reports, in the field of history of medicine, together with a review of
the available literature in PubMed, was undertaken. Giannestras left his
mark in the history of orthopaedics with his clinical work and his
publications, mainly his treatise “Foot Disorders: Medical and Surgical
Management” (1973), while his name lingers in Greece with the
introduction of spine fusion with the use of metallic implants. He was
an eminent university clinical professor of orthopaedics who had
harmonically combined academic writing, teaching and clinical research
in every field of orthopaedic surgery
The Evolution of Spine Surgery in Greece in the Second Half of the 20th Century
Spine Surgery began its evolution in the beginning of the 19th century in order to reach nowadays the point of being considered an important subspecialty of Neurosurgery and Orthopaedics. The purpose of this historical review is the search and evaluation of the progress in spine surgery in the second half of the 20th century. This review concerns the evolution of this field in Greece. Special references are made to the achievements of this field, to the departments that practised it, to physicians and surgeons (orthopaedic surgeons, neurosurgeons, radiologists and rheumatologists) who developed this subspecialty and to clinical and scientific work of this time period. Eventually, the progress of medicine and technology who led to the first achievements of this subspecialty are shown and also that this progress followed the development of the National Healthcare System. In Greece, with small exceptions, the new techniques emerged with a certain delay