Biomaterial-associated infections occur on both permanent implants and temporary devices for restoration or support of human functions. Despite increasing use of biomaterials in an aging society, ...comparatively few biomaterials have been designed that effectively reduce the incidence of biomaterial-associated infections. This review provides design guidelines for infection-reducing strategies based on the concept that the fate of biomaterial implants or devices is a competition between host tissue cell integration and bacterial colonization at their surfaces.
MRI provides unparalleled visualisation of all the anatomical structures involved in the osteoarthritis (OA) process. There is a need for reliable methods of quantifying abnormalities of these ...structures. The aim of this work was to assess the reliability of a novel MRI scoring system for evaluating OA of the knee and explore the validity of the bone marrow lesion (BML) scoring component of this new tool.
After review of the relevant literature, a collaborative group of rheumatologists and radiologists from centres in the UK and USA established preliminary anatomical divisions, items (necessarily broadly inclusive) and scaling for a novel semi-quantitative knee score. A series of iterative reliability exercises were performed to reduce the initial items, and the reliability of the resultant Boston-Leeds Osteoarthritis Knee Score (BLOKS) was examined. A further sample had both the BLOKS and WORMS (Whole Organ MRI Score) bone marrow lesion (BML) score performed to assess the construct validity (relation to knee pain) and longitudinal validity (prediction of cartilage loss) of each scoring method.
The BLOKS scoring method assesses nine intra-articular regions and contains eight items, including features of bone marrow lesions, cartilage, osteophytes, synovitis, effusions and ligaments. The scaling for each feature ranges from 0-3. The inter-reader reliability for the final BLOKS items ranged from 0.51 for meniscal extrusion up to 0.79 for meniscal tear. The reliability for other key features was 0.72 for BML grade, 0.72 for cartilage morphology, and 0.62 for synovitis. Maximal BML size on the BLOKS scale had a positive linear relation with visual analogue scale (VAS) pain, however the WORMS scale did not. Baseline BML was associated with cartilage loss on both BLOKS and WORMS scale. This association was stronger for BLOKS than WORMS.
We have designed a novel scoring system for MRI OA knee, BLOKS, that demonstrates good reliability. Preliminary inspection of the validity of one of the components of this new tool supports the validity of the BLOKS BML scoring method over an existing instrument. Further iterative development will include validation for use in both clinical trials and epidemiological studies.
Tendon and ligament imaging Hodgson, R J; O'Connor, P J; Grainger, A J
British journal of radiology
85, Številka:
1016
Journal Article
Recenzirano
Odprti dostop
MRI and ultrasound are now widely used for the assessment of tendon and ligament abnormalities. Healthy tendons and ligaments contain high levels of collagen with a structured orientation, which ...gives rise to their characteristic normal imaging appearances as well as causing particular imaging artefacts. Changes to ligaments and tendons as a result of disease and injury can be demonstrated using both ultrasound and MRI. These have been validated against surgical and histological findings. Novel imaging techniques are being developed that may improve the ability of MRI and ultrasound to assess tendon and ligament disease.
Ultrasound imaging plays an important role in the diagnosis, monitoring and treatment of injuries in professional soccer players. With the rapid increase in the availability of hand-held portable ...ultrasound devices and the pressure to make timely and accurate diagnosis in professional soccer where return to play time is crucial, ultrasound imaging is an essential diagnostic tool. In this article, we discuss examples of injuries that can be adequately assessed by ultrasound imaging alone and injuries where ultrasound imaging provides a useful first step to guide further investigation and management.
Objectives. Diffuse swelling of the distal interphalangeal (DIP) joint beyond the joint margin is a common feature of arthritis in psoriatic arthritis (PsA). The purpose of this study was to explore ...the microanatomical basis for the inflammation and nail disease in PsA using a combined high-resolution magnetic resonance imaging (MRI) and histological studies.
Methods. High-resolution MRIs of the DIP joint were obtained in 30 subjects 10 PsA, 10 osteoarthritis (OA) and 10 normal volunteers. The relationship between the DIP joint capsule and associated tendon enthesis and the nail bed and root were evaluated. Histological studies to define the relationship between the normal cadaveric DIP joint capsule and the nail root were performed on the middle and ring fingers of 10 dissecting room cadavers.
Results. On MRI, the dorsal capsular enthesis was the epicentre of an inflammatory reaction. This extended to involve the soft tissues adjacent to the nail in 8 of 10 cases in PsA, but only 4 of 10 cases in OA where the inflammation is less intense and in none of the normal fingers. The DIP joint capsule was intimately linked with the nail complex on histology, with the dorsal, volar and lateral aspects of the nail bed being ensheathed in fibres extending from the entheses.
Conclusion. The study suggests that the extended nature of the enthesis organ associated with the DIP joint may explain the diffuse nature of the inflammatory response around the nail in PsA. Therefore the nail is as much an integral part of the enthesis organ as it is of the skin, which has implications for a better understanding of the disease.
Objective
To compare the diagnostic accuracy of conventional 3T MRI against 1.5T MR arthrography (MRA) in patients with clinical femoroacetabular impingement (FAI).
Methods
Sixty-eight consecutive ...patients with clinical FAI underwent both 1.5T MRA and 3T MRI. Imaging was prospectively analysed by two musculoskeletal radiologists, blinded to patient outcomes and scored for internal derangement including labral and cartilage abnormality. Interobserver variation was assessed by kappa analysis. Thirty-nine patients subsequently underwent hip arthroscopy and surgical results and radiology findings were analysed.
Results
Both readers had higher sensitivities for detecting labral tears with 3T MRI compared to 1.5T MRA (not statistically significant p=0.07). For acetabular cartilage defect both readers had higher statistically significant sensitivities using 3T MRI compared to 1.5T MRA (p=0.02). Both readers had a slightly higher sensitivity for detecting delamination with 1.5T MRA compared to 3T MRI, but these differences were not statistically significant (p=0.66). Interobserver agreement was substantial to perfect agreement for all parameters except the identification of delamination (3T MRI showed moderate agreement and 1.5T MRA substantial agreement).
Conclusion
Conventional 3T MRI may be at least equivalent to 1.5T MRA in detecting acetabular labrum and possibly superior to 1.5T MRA in detecting cartilage defects in patients with suspected FAI.
Key Points
•
Conventional 3T MRI is equivalent to 1.5T MRA for diagnosing labral tears.
•
Conventional 3T MRI is superior to 1.5T MRA for diagnosing acetabular cartilage defect.
•
Conventional 3T MRI is equivalent to 1.5T MRA for diagnosing cartilage delamination.
•
Symptom severity score was significantly higher (p<0.05) in group proceeding to surgery.
Abstract Biomaterials-associated infection incidence represents an increasing clinical challenge as more people gain access to medical device technologies worldwide and microbial resistance to ...current approaches mounts. Few reported antimicrobial approaches to implanted biomaterials ever get commercialized for physician use and patient benefit. This is not for lack of ideas since many thousands of claims to new approaches to antimicrobial efficacy are reported. Lack of translation of reported ideas into medical products approved for use, results from conflicting goals and purposes between the various participants involved in conception, validation, development, commercialization, safety and regulatory oversight, insurance reimbursement, and legal aspects of medical device innovation. The scientific causes, problems and impressive costs of the limiting clinical options for combating biomaterials-associated infection are well recognized. Demands for improved antimicrobial technologies constantly appear. Yet, the actual human, ethical and social costs and consequences of their occurrence are less articulated. Here, we describe several clinical cases of biomaterials-associated infections to illustrate the often-missing human elements of these infections. We identify the current societal forces at play in translating antimicrobial research concepts into clinical implant use and their often-orthogonal constituencies, missions and policies. We assert that in the current complex environment between researchers, funding agencies, physicians, patients, providers, producers, payers, regulatory agencies and litigators, opportunities for translatable successes are minimized under the various risks assumed in the translation process. This argues for an alternative approach to more effectively introduce new biomaterials and device technologies that can address the clinical issues by providing patients and medical practitioners new options for desperate clinical conditions ineffectively addressed by biomedical innovation.
Summary Peripheral joint osteoarthritis (OA) is predominantly a clinical diagnosis, though imaging may provide confirmation and aid with differential diagnosis where there is clinical doubt. Whilst ...radiographs (X-rays (XR)) are usually the first-line imaging modality selected, magnetic resonance imaging (MRI), ultrasound and computed tomography (CT) may all have a valuable role in assessing a person with OA, although each has its particular advantages and disadvantages. MRI is of particular use for diagnosing bone conditions that may cause a rapid increase in symptoms, such as avascular necrosis (AVN) or a subchondral insufficiency fracture (SIF), while providing concomitant soft tissue assessment. Ultrasound offers rapid assessment of peripheral joints and can easily assess for features of inflammatory arthritis. CT is faster to perform than MRI and can also image the subchondral bone, but does involve ionising radiation. Selecting the correct imaging modality, in the context of its advantages when visualising a specific joint (e.g., hand vs knee) and with clinical context in mind, will enhance the added value of imaging in clinical practice.
Objectives
To assess the ability of quantitative T2, diffusion tensor imaging (DTI) and radiologist’s scores to detect muscle changes following acute muscle tear in soccer and rugby players. To ...assess the ability of these parameters to predict return to play times.
Methods
In this prospective, longitudinal study, 13 male athletes (age 19 to 34 years; mean 25 years) underwent MRI within 1 week of suffering acute muscle tear. Imaging included measurements of T2 and DTI parameters. Images were also assessed using modified Peetrons and British athletics muscle injury classification (BAMIC) scores. Participants returned for a second scan within 1 week of being determined fit to return to play. MRI measurements were compared between visits. Pearson’s correlation between visit 1 measurements and return to play times was assessed.
Results
There were significant differences between visits in BAMIC scores (
Z
= − 2.088;
p
= 0.037), modified Peetrons (
Z
= − 2.530;
p
= 0.011) and quantitative MRI measurements; T2, 13.12 ms (95% CI, 4.82 ms, 21.42 ms;
p
= 0.01); mean diffusivity (0.22 (0.04, 0.39);
p
= 0.02) and fractional anisotropy (0.07 (0.01, 0.14);
p
= 0.03). BAMIC scores showed a significant correlation with return to play time (
R
s
= 0.64;
p
= 0.02), but modified Peetrons scores and quantitative parameters did not.
Conclusions
T2 and DTI measurements in muscle can detect changes due to healing following muscle tear. Although BAMIC scores correlated well with return to play times, in this small study, quantitative MRI values did not, suggesting that T2 and DTI measurements are inferior predictors of return to play time compared with visual scoring.
Key Points
•
Muscle changes following acute muscle tear can be measured using T2 and diffusion measurements on MRI
.
•
Measurements of T2 and diffusion using MRI are not as good as a radiologist’s visual report at predicting return to play time after acute muscle tear
.
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