Functional Characteristics and Mechanical Performance of PCU Composites for Knee Meniscus Replacement.

The potential use of fiber-reinforced based polycarbonate-urethanes (PCUs) as candidate meniscal substitutes was investigated in this study. Mechanical test pieces were designed and fabricated using a compression molding technique. Ultra-High Molecular Weight Polyethylene (UHMWPE) fibers were impregnated into PCU matrices, and their mechanical and microstructural properties evaluated.

Novel imaging approaches to screen for breast cancer: Recent advances and future prospects.

Aim Of The Study: Over the past 50 years, the application of mammography - an X-ray of the breast - to screen healthy women has been a successful strategy to reduce breast cancer mortality. The aim of this study was to review the literature on novel imaging approaches that have the potential to replace mammography.

Methods: An online literature search was carried out using PubMed, Google Scholar, ScienceDirect and Google Patents.

Detecting Breast Cancer with a Dual-Modality Device.

Although mammography has been the gold standard for the early detection of breast cancer, if a woman has dense breast tissue, a false negative diagnosis may occur. Breast ultrasound, whether hand-held or automated, is a useful adjunct to mammography but adds extra time and cost. The primary aim was to demonstrate that our second-generation Aceso system, which combines full-field digital mammography (FFDM) and automated breast ultrasound (ABUS) in a single platform, is able to produce improved quality images that provide clinically meaningful results.

Testing a dual-modality system that combines full-field digital mammography and automated breast ultrasound.

Purpose: The aim of this study was to test a novel dual-modality imaging system that combines full-field digital mammography (FFDM) and automated breast ultrasound (ABUS) in a single platform. Our Aceso system, named after the Greek goddess of healing, was specifically designed for the early detection of cancer in women with dense breast tissue.

Materials And Methods: Aceso was first tested using two industry standards: a Contrast Detail Mammography (CDMAM) phantom as endorsed by European Reference Organisation for Quality Assured Breast Screening and Diagnostic Services was used to assess the FFDM images; and the CIRS 040GSE ultrasound phantom was imaged to evaluate the quality of the ABUS images.

Symmetry, not asymmetry, of abdominal muscle morphology is associated with low back pain in cricket fast bowlers.

Objectives: Although abdominal muscle morphology is symmetrical in the general population, asymmetry has been identified in rotation sports. This asymmetry includes greater thickness of obliquus internus abdominis (OI) on the non-dominant side in cricketers. Cricket fast bowlers commonly experience low back pain (LBP) related to bowling action, and this depends on trunk muscle control.

Diagnosing breast cancer: an opportunity for innovative engineering.

Background: In an ancient papyrus, dating back to 2500 BC, an Egyptian named Imhotep, thought to be the first physician and engineer in history, offers a glimpse into the earliest recorded case of breast cancer. Treatment has evolved over the years, from radical mastectomy to radiation by X-rays, and from adjuvant chemotherapy to hormonal therapy. A key challenge in fighting the 'war' on breast cancer is early diagnosis and here innovative engineers play a vital role.

Gait status 17-26 years after selective dorsal rhizotomy.

The purpose of this study was to use three-dimensional gait analysis to describe the gait status of adults with spastic diplegia who underwent selective dorsal rhizotomy (SDR) in childhood. Outcome measures were the gait deviation index (GDI), non-dimensional temporal-distance parameters, and kinematics of the lower limbs. A total of 31 adults with spastic diplegia who had previously undergone SDR were eligible and participated in current study (SDR group).

Level of activity and participation in adults with spastic diplegia 17-26 years after selective dorsal rhizotomy.

Objective: To evaluate the activity and participation levels of adults with spastic diplegia 17-26 years after selective dorsal rhizotomy; to investigate relationships between subjects' functioning and age, socio-economic-status, level of satisfaction and their perceptions of the post-operative outcomes.

Design: Observational follow-up study.

Patients: Thirty-one subjects with spastic diplegia, age range 21-44 years, who underwent selective dorsal rhizotomy between 1981 and 1991.

Knee rotational laxity in a randomized comparison of single- versus double-bundle anterior cruciate ligament reconstruction.

Background: While single-bundle anterior cruciate ligament reconstruction reduces anterior-posterior laxity, studies have demonstrated residual rotational instability. Improved pivot-shift results have been shown with the double-bundle graft; however, no study has compared rotational laxity outcome of these surgical techniques in vivo under quantified, isolated torsional loading.

Hypothesis: The anterior cruciate ligament-deficient knee exhibits greater rotational laxity than the contralateral uninjured knee.

Survey of investigators' opinions on the acceptability of interactions with patients participating in clinical trials.

Introduction: There is growing concern about the ability of clinical trials to reliably detect differences between active drugs and placebo. To date, little attention has focused on how interactions between clinical trial investigators and patients may influence study outcomes. We sought to explore what types of interactions with patients investigators considered to be appropriate during placebo-controlled pharmacotherapy studies of major depressive disorder.

Incidence of spinal abnormalities in patients with spastic diplegia 17 to 26 years after selective dorsal rhizotomy.

Introduction: The aim of this study was to evaluate the mechanical status of the spine in patients with spastic diplegia 17-26 years after selective dorsal rhizotomy (SDR).

Methods: We compared original radiographic reports from our earlier short-term follow-up study with current X-rays. In addition, we obtained magnetic resonance images (MRI) of the spine and additional information regarding back pain and clinical assessments.

Functional status of patients with cerebral palsy according to the International Classification of Functioning, Disability and Health model: a 20-year follow-up study after selective dorsal rhizotomy.

Objective: To determine functional status of patients with cerebral palsy 20 years after they received selective dorsal rhizotomy (SDR).

Design: A prospective 20-year follow-up study.

Setting: Red Cross Children's Hospital (SDR operation and 1-year follow-up assessment) and at institutional or private locations nearby patients' homes (20-year follow-up assessment).

A prospective gait analysis study in patients with diplegic cerebral palsy 20 years after selective dorsal rhizotomy.

Objectives: Selective dorsal rhizotomy (SDR) has been widely performed for the reduction of spasticity in patients with cerebral palsy during the past 2 decades. The objective of this study was to determine whether the surgery has yielded long-term functional benefits for these patients.

Methods: The authors present results from a prospective 20-year follow-up study of locomotor function in 13 patients who underwent an SDR in 1985.

Dynamic similarity predicts gait parameters for Homo floresiensis and the Laetoli hominins.

Late in 2004, the skeletal remains of a pygmy-sized hominin recovered from a cave on the Indonesian island of Flores were first documented, with the authors concluding that the "postcranial anatomy [was] consistent with human-like obligate bipedalism" (Brown et al. [2004]: Nature 431:1055-1061). We have assumed that Homo floresiensis, who was estimated to be 18,000-years-old, walked with a gait pattern that was dynamically similar to modern man.

The position of the head and centre of mass during the front foot off-drive in skilled and less-skilled cricket batsmen.

The aim of this study was to compare selected kinematic variables of the front foot off-drive in skilled and less-skilled cricket batsmen. High-speed digital cameras were used to record the three-dimensional kinematics of 10 skilled and 10 less-skilled right-handed batsmen when playing a shadow front foot off-drive to realistic projected video footage. Skilled batsmen were more likely to identify the type of delivery bowled.

Selective dorsal rhizotomy: long-term experience from Cape Town.

Introduction: Given the large number of cerebral palsy patients who have undergone selective dorsal rhizotomy in the past two decades, it is clearly imperative that the clinical community be provided with objective and compelling evidence of the long-term sequelae of the procedure.

Materials And Methods: In the early 1980s, Peacock in Cape Town shifted the site of the rhizotomy from the conus medullaris to the cauda equina, and in the past 25 years, more than 200 children have been operated on. We have studied the incidence of spinal deformities after multiple-level laminectomy and recorded a 20% incidence of isthmic spondylolysis or grade-I spondylolisthesis.

Design of surface electrode array for measuring conduction velocity in the human genioglossus muscle.

A new appliance, incorporating linear arrays of pin electrodes for genioglossus (GG) surface electromyography measurement, is presented. This design enables the estimation of GG muscle fiber conduction velocity, which decreases with fatigue. The performance of the device was evaluated for ten healthy human subjects during fatiguing and force varying contractions.

Automatic detection of gait events using kinematic data.

The timing of heel strike (HS) and toe off (TO), the events that mark the transitions between stance and swing phase of gait, is essential when analysing gait. Force plate recordings are routinely used to identify these events. Additional instrumentation, such as force sensitive resistors, can also been used.

A brain-behaviour initiative for South Africa: the time is right.

Background: Many have advocated for science and health research in developing world settings. However, there has been less focus on the value of basic and clinical neuroscience research in this context. The current paper focuses on the relevance of a brain-behaviour research initiative in South Africa.

Differences in lower limb transverse plane joint moments during gait when expressed in two alternative reference frames.

When comparing previous studies that have measured the three-dimensional moments acting about the lower limb joints (either external moments or opposing internal joint moments) during able-bodied adult gait, significant variation is apparent in the profiles of the reported transverse plane moments. This variation cannot be explained on the basis of adopted convention (i.e.

A gait nomogram used with fuzzy clustering to monitor functional status of children and young adults with cerebral palsy.

We have developed a gait nomogram based on dynamic similarity to characterize and compare neuromuscular function. We used temporal-distance data based on 669 normal participants (age range 5 to 98 years), and 78 children and young adults with spastic diplegia (43 males, 35 females; mean age 10 y 8 mo, standard deviation 3 y 11 mo, range 5 to 20 y), all of whom were independent ambulators. A new statistical algorithm known as fuzzy clustering was implemented and five cluster centres were identified, each representing distinct walking strategies adopted by children with cerebral palsy.

Froude and the contribution of naval architecture to our understanding of bipedal locomotion.

It is fascinating to think that the ideas of two 19th century naval architects could offer useful insights for 21st century scientists contemplating the exploration of our planetary system or monitoring the long-term effects of a neurosurgical procedure on gait. The Froude number, defined as Fr = v2/gL, where v is velocity, g is gravitational acceleration and L is a characteristic linear dimension (such as leg length), has found widespread application in the biomechanics of bipedal locomotion. This review of two parameters, Fr and dimensionless velocity beta = (Fr)1/2, that have served as the criterion for dynamic similarity, has been arranged in two parts: (I) historical development, including the contributions by William Froude and his son Edmund, two ship designers who lived more than 130 years ago, the classic insights of D'Arcy Wentworth Thompson who, in his magnum opus On Growth and Form, espoused the connection between mathematics and biology, and the pioneering efforts of Robert McNeill Alexander, who popularised the application of Fr to animal locomotion; and (II) selected applications, including a comparison of walking for people of different heights, exploring the effects of different gravitational fields on human locomotion, establishing the impact of pathology and the benefits of treatment, and understanding the walking patterns of bipedal robots.