Accurate Noninvasive Arterial Assessment of the Wounded Lower Limb: A Clinical Challenge for Wound Practitioners

2020 ◽  
Vol 19 (3) ◽  
pp. 215-226 ◽  
Author(s):  
Peta Ellen Tehan ◽  
Alex Louise Barwick ◽  
Sarah Louise Casey ◽  
Sean Michael Lanting ◽  
Vivienne Helaine Chuter
Keyword(s):  
Lower Limb ◽  
Assessment Methods ◽  
Noninvasive Testing ◽  
Patient Specific ◽  
Accurate Information ◽  
Testing Methods ◽  
Vascular Assessment ◽  
Wound Assessment ◽  
Lower Extremity Wound ◽  
Assessment Guidelines

Arterial investigations are an essential part of lower extremity wound assessment. The results of these investigations assist the wound clinician to determine the etiology of the wound, predict healing capacity, and inform further management. There are a number of noninvasive testing methods available to practitioners, all with varying levels of reliability and accuracy. Clinical wound assessment guidelines give varied recommendations when it comes to lower limb vascular assessment in the presence of a wound. This leaves clinicians with little guidance on how to choose the most appropriate test, and uncertainty remains about which tests provide the most accurate information in different patient-specific contexts. Conditions such as advanced age, diabetes, and renal disease are known to affect the accuracy of some commonly used lower limb arterial assessment methods, and alternate testing methods should be considered in these cases. This seminal review discusses the reliability and accuracy of lower limb vascular assessment methods used to guide lower limb arterial assessment in the presence of wounds.

scholarly journals PET-Specific Parameters and Radiotracers in Theoretical Tumour Modelling

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Matthew Jennings ◽  
Loredana G. Marcu ◽  
Eva Bezak
Keyword(s):  
Gene Expression ◽  
In Silico ◽  
Tumour Growth ◽  
Patient Specific ◽  
Computational Techniques ◽  
Accurate Information ◽  
Pet Ct ◽  
Ct Data ◽  
Specific Management

The innovation of computational techniques serves as an important step toward optimized, patient-specific management of cancer. In particular,in silicosimulation of tumour growth and treatment response may eventually yield accurate information on disease progression, enhance the quality of cancer treatment, and explain why certain therapies are effective where others are not.In silicomodelling is demonstrated to considerably benefit from information obtainable with PET and PET/CT. In particular, models have successfully integrated tumour glucose metabolism, cell proliferation, and cell oxygenation from multiple tracers in order to simulate tumour behaviour. With the development of novel radiotracers to image additional tumour phenomena, such as pH and gene expression, the value of PET and PET/CT data for use in tumour models will continue to grow. In this work, the use of PET and PET/CT information inin silicotumour models is reviewed. The various parameters that can be obtained using PET and PET/CT are detailed, as well as the radiotracers that may be used for this purpose, their utility, and limitations. The biophysical measures used to quantify PET and PET/CT data are also described. Finally, a list ofin silicomodels that incorporate PET and/or PET/CT data is provided and reviewed.

Varieties of Authentic Assessment

2011 ◽  
pp. 936-942
Author(s):  
Karen R. Juneau
Keyword(s):  
Public Education ◽  
Technology Assessment ◽  
Real World ◽  
Authentic Assessment ◽  
Feedback System ◽  
Assessment Methods ◽  
Education Student ◽  
Testing Methods ◽  
Instructional Feedback ◽  
Authentic Assessments

The need for effective assessments has been recognized since the earliest days of public education. Student testing provides rationales and support for many activities, including instructional feedback, system monitoring, appropriate selection and placement of students, and certification of skills (U.S. Congress, Office of Technology Assessment, 1992). With the growing recognition that learning is an individual accomplishment and that learning takes place in context, traditional testing methods need to be supplemented to accurately assess achievement (Brown, Collins, & Duguid, 1989; Eisner, 1999). Authentic assessments are designed to accurately reflect the real world situations in which the skills and knowledge that students developed would be applied. Although there are a variety of authentic assessment methods, each method encourages linkages between the classroom experience and real world applications. This does not mean that traditional forms of testing are obsolete, rather that these methods should be supplemented by information gathered from more situational methods.

Enhanced vascular assessment by ultrasound using microbubble contrast after percutaneous decannulation of peripheral veno-arterial extracorporeal membrane oxygenation

2020 ◽  
pp. 112972982093241
Author(s):  
Shek Yin Au ◽  
Kwong Shun Chan ◽  
Ka Man Fong ◽  
Sai Kwong Yung ◽  
Wing Yiu George Ng ◽  
...  
Keyword(s):  
Extracorporeal Membrane Oxygenation ◽  
Lower Limb ◽  
Arterial Stenosis ◽  
Closure Device ◽  
Acute Thrombosis ◽  
Vascular Assessment ◽  
Vascular Ultrasound ◽  
Membrane Oxygenation ◽  
Ultrasound Contrast ◽  
Careful Assessment

Termination of peripheral veno-arterial extracorporeal membrane oxygenation support by managing the arteriotomy wound using a percutaneous closure device was reported successful and effective. However, careful assessment by clinical examination and also ultrasound Doppler assessment of the lower limb vasculature after closure is of paramount importance. Complications including pseudoaneurysm, arterial stenosis, and acute thrombosis are not uncommon. In this case report, commercial microbubbles were used as ultrasound contrast to enhance the image quality for better vascular ultrasound and Doppler assessment after veno-arterial extracorporeal membrane oxygenation percutaneous decannulation. A peudoaneurysm was revealed after microbubble injection, which would otherwise be missed.

scholarly journals Mechanical and Anatomical Axis in Total Ankle Arthroplasty

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0008
Author(s):  
Ali-Asgar Najefi ◽  
Andrew Goldberg
Keyword(s):  
Lower Limb ◽  
Mechanical Axis ◽  
Normal Group ◽  
Total Ankle Arthroplasty ◽  
Coronal Plane ◽  
Patient Specific ◽  
Ankle Arthroplasty ◽  
Patient Specific Instrumentation ◽  
Significant Difference ◽  
Anatomical Axis

Category: Ankle Arthritis Introduction/Purpose: Inadequate correction of alignment in the coronal, sagittal or axial planes will inevitably lead to failure of the Total Ankle Arthroplasty (TAA). The mechanical axis of the lower limb (MAL), the mechanical axis of the tibia (MAT) and the anatomical axis of the tibia (AAT) are three recognized coronal plane measurements using plain radiography. The relationship between anatomical and mechanical axes depends on the presence of femoral or tibial deformities from trauma or inherited conditions, or previous corrective or replacement surgery. Ankle arthroplasty relies heavily on preoperative radiographs or CT scans and the purpose of this study was to assess whether MAL, MAT and AAT are the same in a cohort of patients upon which placement of TAA is considered. Methods: We analysed 75 patients operated on between 2015 and 2016 at a specialist tertiary centre for elective orthopaedic surgery. All patients had a pre-operative long leg radiograph. They were split into 2 groups. The first group had known deformity proximal to the ankle (such as previous tibial or femoral fracture, severe arthritis, or previous reconstructive surgery) and the second group had no clinically detectable deformity. The MAL, MAT and AAT were assessed and the difference between these values was calculated. Results: There were 54 patients in the normal group, and 21 patients in the deformity group. Overall, 25 patients(33%) had a difference between all three axes of less than 1 degree. In 33 patients(44%), there was a difference in one of the axes of ≥2 degrees. There was no significant difference between MAT and AAT in patients in the normal group(p=0.6). 95% of patients had a difference of <1 degree. There was a significant difference between the MAT and AAT in patients in the deformity group(p<0.01). In the normal group, 39 patients(73%) had a difference of <2 degrees between the AAT and MAL. In the deformity group, only 10 patients (48%) had a difference of <2 degrees.In fact, 24% of patients had a difference ≥3 degrees. Conclusion: Malalignment in the coronal plane in TAA may be an issue that we have not properly addressed. Up to 66% of patients without known deformity may have a TAA that is placed at least 1 degree incorrectly relative to the MAL. We recommend the use of full-length lower limb radiographs when planning a TAA in order to plan the placement of implants. The decision to perform extramedullary referencing, intramedullary referencing, or patient specific Instrumentation must be part of the pre-operative planning process.

Vascular Assessment in Patients With a Lower Limb Wound: A Correlational Study of Photoplethysmography and Laser Doppler Flowmetry Toe Pressure Techniques

2020 ◽  
pp. 193229682097997
Author(s):  
Jérôme Patry ◽  
Louis Laurencelle ◽  
Justine Bélisle ◽  
Maryse Beaumier
Keyword(s):  
Laser Doppler Flowmetry ◽  
Pressure Measurement ◽  
Lower Limb ◽  
Laser Doppler ◽  
Lower Limbs ◽  
Correlational Study ◽  
Care Clinic ◽  
Doppler Flowmetry ◽  
Vascular Assessment ◽  
Toe Pressure

Background: Vascular assessment of the lower limbs is essential in patients with diabetes. In the presence of noncompressible arteries, the ankle brachial index (ABI) can either be inconclusive or provide false-positive results. Toe pressure measurement has been suggested as an alternative as a noninvasive method for detecting peripheral arterial disease (PAD). Toe pressure measurement can be performed either by photoplethysmography (PPG) or by Laser Doppler flowmetry (LDF). The aim of this study was to determine correlations between the two techniques in order to promote the use of PPG in clinical practice. Methods: This was a prospective correlational study of 108 consecutive recruited adult patients, with and without diabetes, with at least one lower limb wound from a University-affiliated hospital wound care clinic. Toe pressure measurements were both performed with PPG and LDF devices. Results: Mean toe pressure values for PPG and LDF were, respectively, 83.7 (SD 35.4) and 79.5 (SD 32.0) mmHg (with a paired t-test 3.969, P < 0.01). In patients with at least one lower limb wound, a strong linear relation was found between PPG and LDF toe pressure techniques with a Pearson’s r correlation coefficient of 0.920 ( P < 0.001). Conclusions: PPG and LDF toe pressure techniques are equivalent in patients with at least one lower limb wound, irrespective of the presence of diabetes. Therefore, in the presence of an ABI with inconclusive results, such as in a patient with noncompressible vessels, both toe pressure techniques can be used for assessing the vascular supply of the lower limb with a wound.

scholarly journals Computer-Assisted Planning and Three-Dimensional-Printed Patient-Specific Instrumental Guide for Corrective Osteotomy in Post-Traumatic Femur Deformity: A Case Report and Literature Review

2018 ◽  
Vol 24 (1) ◽  
pp. 12-17 ◽  
Author(s):  
Lau Chi-Kay ◽  
Chui King-him ◽  
Lee Kin-bong ◽  
Li Wilson
Keyword(s):  
Lower Limb ◽  
New Technologies ◽  
Preoperative Planning ◽  
Corrective Osteotomy ◽  
Three Dimensional ◽  
Patient Specific ◽  
Computer Assisted ◽  
Limb Deformity ◽  
Satisfactory Outcome ◽  
Post Traumatic

Post-traumatic limb deformity is often multiplanar and thus is a difficult pathology to deal with surgically. Precise preoperative planning and accurate intraoperative execution are two main important steps that lead to satisfactory outcome. Computer-assisted planning and three-dimensional-printed patient-specific instrumental guides provide excellent aid to the two steps, respectively. We report a case of posttraumatic lower limb deformity in a patient who underwent closing wedge corrective osteotomy with the aid of the aforementioned new technologies.

scholarly journals Restricted Kinematic Alignment, the Fundamentals, and Clinical Applications

2021 ◽  
Vol 8 ◽  
Author(s):  
Pascal-André Vendittoli ◽  
Sagi Martinov ◽  
William G. Blakeney
Keyword(s):  
Lower Limb ◽  
Soft Tissues ◽  
Computer Navigation ◽  
Patient Specific ◽  
Control Group ◽  
Kinematic Alignment ◽  
Knee Anatomy ◽  
Normal Knee ◽  
Patient Specific Instrumentation ◽  
Patient Reported

Introduction: After a better understanding of normal knee anatomy and physiology, the Kinematic Alignment (KA) technique was introduced to improve clinical outcomes of total knee arthroplasty (TKA). The goal of the KA technique is to restore the pre-arthritic constitutional lower limb alignment of the patient. There is, however, a large range of normal knee anatomy. Unusual anatomies may be biomechanically inferior and affect TKA biomechanics and wear patterns. In 2011, the leading author proposed the restricted kinematic alignment (rKA) protocol, setting boundaries to KA for patients with an outlier or atypical knee anatomy.Material and Equipment: rKA aims to reproduce the constitutional knee anatomy of the patient within a safe range. Its fundamentals are based on sound comprehension of lower limb anatomy variation. There are five principles describing rKA: (1) Combined lower limb coronal orientation should be ± 3° of neutral; (2) Joint line orientation coronal alignment should be within ± 5° of neutral; (3) Natural knee's soft tissues tension/ laxities should be preserved/restored; (4) Femoral anatomy preservation is prioritized; (5) The unloaded/most intact knee compartment should be resurfaced and used as the pivot point when anatomical adjustment is required. An algorithm was developed to facilitate the decision-making.Methods: Since ~50% of patients will require anatomic modification to fit within rKA boundaries, rKA is ideally performed with patient-specific instrumentation (PSI), intra-operative computer navigation or robotic assistance. rKA surgical technique is presented in a stepwise manner, following the five principles in the algorithm.Results: rKA produced excellent mid-term clinical results in cemented or cementless TKA. Gait analysis showed that rKA TKA patients had gait patterns that were very close to a non-operated control group, and these kinematics differences translated into significantly better postoperative patient-reported scores than mechanical alignment (MA) TKA cases.Discussion: Aiming to improve the results of MA TKA, rKA protocol offers a satisfactory compromise that recreates patients' anatomy in most cases, omitting the need for extensive corrections and soft tissue releases that are often required with MA. Moreover, it precludes the reproduction of extreme anatomies seen with KA.

Lower Limb Assistive Device Design Optimization Using Musculoskeletal Modeling: A Review

2019 ◽  
Vol 13 (4) ◽  
Author(s):  
Emerson Paul Grabke ◽  
Kei Masani ◽  
Jan Andrysek
Keyword(s):  
Design Optimization ◽  
Lower Limb ◽  
Musculoskeletal Model ◽  
Musculoskeletal Modeling ◽  
Model Complexity ◽  
Clinical Population ◽  
Assistive Device ◽  
Patient Specific ◽  
Device Design ◽  
Musculoskeletal Models

Abstract Many individuals with lower limb amputations or neuromuscular impairments face mobility challenges attributable to suboptimal assistive device design. Forward dynamic modeling and simulation of human walking using conventional biomechanical gait models offer an alternative to intuition-based assistive device design, providing insight into the biomechanics underlying pathological gait. Musculoskeletal models enable better understanding of prosthesis and/or exoskeleton contributions to the human musculoskeletal system, and device and user contributions to both body support and propulsion during gait. This paper reviews current literature that have used forward dynamic simulation of clinical population musculoskeletal models to perform assistive device design optimization using optimal control, optimal tracking, computed muscle control (CMC) and reflex-based control. Musculoskeletal model complexity and assumptions inhibit forward dynamic musculoskeletal modeling in its current state, hindering computational assistive device design optimization. Future recommendations include validating musculoskeletal models and resultant assistive device designs, developing less computationally expensive forward dynamic musculoskeletal modeling methods, and developing more efficient patient-specific musculoskeletal model generation methods to enable personalized assistive device optimization.

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