Biomedical subjects

A Jackson

Publications and source records attributed to A Jackson.

411 records · Page 23Linked to original sources

PubMedDate not supplied

Genucom, KT-1000, and Stryker knee laxity measuring device comparisons. Device reproducibility and interdevice comparison in asymptomatic subjects.

Generally, three devices (the Genucom Knee Analysis System, the MEDmetric KT-1000 Arthrometer, and the Stryker Knee Laxity Tester), which have been presented in the literature, may be used to assess clinically the amount of knee laxity in an objective manner. This study compared the reproducibility of the anterior and posterior knee laxity values for each and made direct comparisons of the results obtained. Thirty asymptomatic subjects were given a test-retest protocol on both legs with all three devices. Devices were tested in a counterbalanced order. Repeatability of test values within devices was variable, but all were acceptable, the lowest being r = 0.74. Analysis of variance (AN-OVA), and correlational analysis revealed that device-specific anterior and posterior laxity values were produced. We concluded that each commercially available knee laxity testing device can provide reproducible quantitative measurements of knee laxity; however, due to differences in device sensitivities and functional design, numerical results from one device cannot be generalized to another device.

Adult↗

PubMedDate not supplied

The effects of knee brace wear on perceptual and metabolic variables during horizontal treadmill running.

Past research has indicated that runners who wear a Lenox Hill Derotation Brace during treadmill running at 6 mph have an approximate 5% increase in oxygen consumption compared to those who run without the brace. The present study expanded those findings by determining the metabolic and perceptual effects of wearing four commercially available braces while treadmill running at speeds of 6, 7, and 8 mph. The four braces used in this study were the Generation II Poli-Axial Knee Cage, the Orthotech Performer, the CTi Brace, and the Lenox Hill Derotation Brace. Results indicated that the braces caused increases (P less than 0.008) in oxygen consumption, heart rate, and ventilation in the 3% to 8% range compared to running without the brace. Peripheral ratings of perceived exertion were also elevated (P less than 0.001) between 9% and 13%. However, no significant differences were found between the braces. Analysis of covariance indicated the weight of the brace accounted for the increased oxygen consumption during the treadmill runs. We concluded that the braces examined in this study will cause a consistent increase in metabolic cost, which is related to the weight of the braces.

Adolescent↗

PubMedDate not supplied

Experience of a self-care unit as part of a hospital-based rehabilitation service.

The nature, advantages and disadvantages, and cost of a hospital-based self-care unit as part of a rehabilitation service are described. The unit's operational policy is critically examined after analysing the records of 40 patients admitted consecutively over a 2-year period and conducting interviews with 27 patients between 4 and 48 weeks after discharge. It is concluded that, compared with a hospital ward, a self-care unit is inexpensive to run and helps to prevent patients from giving up their homes and being admitted to residential homes prematurely. In addition to an assessment and confidence-building role, the unit provides a more appropriate and acceptable environment for patients waiting housing alteration or rehousing than a hospital ward.

Activities of Daily Living↗

PubMedDate not supplied

Memory dysfunction in multiple sclerosis corresponds to juxtacortical lesion load on fast fluid-attenuated inversion-recovery MR images.

BACKGROUND AND PURPOSE: MR imaging is a sensitive diagnostic tool and paraclinical marker of disease activity and prognosis in multiple sclerosis (MS), yet the role of MR imaging of MS is controversial. The aim of this study was to describe the relationship between cognitive function and MS lesion size and position, as shown on comparative images from conventional spin-echo (CSE) and fast fluid-attenuated inversion-recovery (fast FLAIR) MR studies. METHODS: CSE and fast FLAIR sequences consisted of 40 noncontiguous, 3-mm-thick axial sections matched for geometric position in 18 patients with relapsing-remitting MS. Lesions were scored for size, anatomic position, and their comparative appearance on CSE and fast FLAIR images. The neuropsychological assessment tested general psychological performance, memory, and frontal lobe executive function. RESULTS: Fast FLAIR images showed significantly more small (146 versus six) and medium-sized (18 versus four) juxtacortical lesions than did CSE sequences. Small juxtacortical lesions displayed only on fast FLAIR images had a distinctive appearance, suggestive of small areas of perivascular inflammation. The number of these lesions corresponded to reduced performance on the fifth and delayed trials of the Rey Auditory Verbal Learning memory function test. CONCLUSION: Fast FLAIR images show small lesions at the juxtacortical boundary that are not seen on CSE studies. The presence of such lesions correlates with impaired retention of information in memory tasks, which is characteristic of cognitive problems in patients with MS.

Adult↗

PubMedDate not supplied

Combined fat- and water-suppressed MR imaging of orbital tumors.

BACKGROUND AND PURPOSE: The use of a high-resolution T2-weighted MR sequence, which suppresses signal from both fat and water, has been shown to be highly effective for depicting areas of inflammatory damage within the optic nerve. The ability of this sequence to show neoplastic and inflammatory orbital lesions, which may mimic neuritis, is unknown. This study was designed to examine the characteristics of such a sequence for the investigation of orbital mass lesions. METHODS: Twenty-eight patients with known or suspected mass lesions of the orbit and six healthy volunteers were recruited for study. Imaging was performed with a 1.5-T MR unit. Participants were examined by selective partial inversion recovery (SPIR) sequences with T2-weighted fast spin-echo acquisition, selective partial inversion recovery/fluid attenuated inversion recovery (SPIR/FLAIR) sequences with fast spin-echo acquisition, short tau inversion recovery (STIR) sequences with fast spin-echo acquisition, and SPIR sequences with contrast-enhanced T1-weighted fast spin-echo acquisition. Two neuroradiologists, using a randomised, blinded method, scored images for lesion presence and extent. Lesion extent was defined as the number of images with visible abnormality, and was compared with the standard of reference established at a later date by consensus review of all imaging sequences. The ability of the sequences to show the presence and extent of pathologic lesions was compared. RESULTS: The SPIR/FLAIR sequence showed both the presence and extent of orbital masses significantly better than did either STIR or T2-weighted SPIR sequences (P<.01 and P<.001, respectively). Contrast-enhanced T1-weighted SPIR images ranked better than SPIR/FLAIR images, although the difference failed to reach statistical significance. In the orbital apex, the SPIR/FLAIR technique was superior to all other techniques used. This reflected its ability to distinguish enhancing, pathologic lesions from enhancing, normal anatomy. CONCLUSION: SPIR/FLAIR is an appropriate screening technique for orbital masses and offers significant advantages over currently used fat-suppressed sequences for the investigation of orbital disease.

Adolescent↗

PubMedDate not supplied

The orthopaedic management of hypophosphataemic rickets.

The orthopaedic management of 19 patients with hypophosphataemic rickets was reviewed. Three groups of patients could be identified: teenagers or young adults without knee problems, those with knee problems, and adults or elderly patients with stiff joints due to mineralisation of ligaments. Osteotomies were best staged. Diaphyseal osteotomies were performed at all ages with stabilisation over an intramedullary nail; metaphyseal osteotomies were most successful at or close to maturity. Early degeneration of the knees with shedding of the articular cartilage was seen in young adults, and osteochondritis-like lesions were seen in some teenagers. Stiffness and bone pain were a feature in elderly patients.

Adolescent↗

PubMedDate not supplied