Showing papers in "Journal of Orthopaedic Research in 1997"

TL;DR: The delineation of the depth‐dependent modulus provides a basis for detailed study of the relationship between the composition, structure, and function of cartilage in such processes as aging, repair, and degeneration.

TL;DR: Nonuniformity of the anterior cruciate ligament under unconstrained anterior tibial loads is demonstrated and reconstruction techniques should take into account the role of the posterolateral bundle in addition to that of the anteromedial bundle.

TL;DR: The treatment of simple diaphyseal fractures with flexible fixation can be improved by careful reduction of the fracture; this prevents large interfragmentary gaps.

TL;DR: The three parameters investigated were each influenced by the dynamic strain regimens in a distinct manner, implying that the signalling mechanisms involved are uncoupled.

TL;DR: The systematic underestimation error in the platens compression test can be only approximated and is in the range of 20‐40%; the substantial random error (±12.5%) confounds correction, particularly when the sample size is small.

TL;DR: This model provides a useful method for the assay of progenitors of connective tissue from human subjects, examination of the effects of aging and selected disease states on this progenitor population, and investigation into the regulation of human osteoblastic differentiation.

TL;DR: It is suggested that because the level of radiation required to produce an acceptable level of viral inactivation (90 kGy) produces an unacceptable reduction in the mechanical integrity of the bone, low levels of radiation, sufficient to produce bacterial safety, should be used in conjunction with biological tests to ensure viral safety.

TL;DR: The results of this study indicate that adhesive/capsulitis involves both synovial hyperplasia and capsular fibrosis, and Cytokines such as transforming growth factor‐β and platelet‐derived growth factor may be involved in the inflammatory and fibrotic processes in adhesive capsulitis.

TL;DR: It was generally concluded that the nucleus pulposus undergoes a transition from “fluid‐like” behavior to more “solid‐like" behavior with aging and degeneration.

TL;DR: Topical application of transforming growth factor β1, alone or in combination with epidermal growth factor, may have the potential to strengthen the ligament by increasing matrix synthesis during its remodeling and healing processes.

TL;DR: The findings suggest that the age‐related decline in the synthetic response of chondrocytes to insulin‐ like growth factor‐I results, at least in part, from increased expression of insulin‐like growth factor binding protein.

TL;DR: In this article, a study related mechanisms of gait compensations to the level of pain and to limitations in passive motion in patients with osteoarthritis of the hip was conducted.

TL;DR: Mononuclear cells from patients with total hip replacement were some‐how “sensitized” to metal particles in comparison with mononnuclear cells from individuals without an implant, and the chromium orthophosphate corrosion product was a potent macrophage/monocyte activator and may contribute to Macrophage‐mediated osteolysis and aseptic loosening.

TL;DR: An in vitro study of the radial tensile properties of the annulus fibrosus suggests that these values reflect the material behavior of the interlaminar matrix and are an order of magnitude smaller than values used in previous analytical representations of this tissue.

TL;DR: The results suggest that UAMS‐1 expresses virulence Factors that are important in the pathogeritesis of osteomyelitis and that some or all of these virulence factors are either absent or are not expressed jrisfraffl Smith diffuse, and that the model may be appropriate for the identificationf and characterization of thesevirulence factors.

TL;DR: Zonal changes in cell density and axial strain that occurred during static compression correlated well with alterations in metabolic activity, suggesting that zone‐specific variations in mechanical stimuli could be responsible for spatially varied patterns of cartilage metabolic activity under load.

TL;DR: It is demonstrated, using pharmacological inhibitors of a variety of intracellular signalling pathways, that the actin cytoskeleton, the phospholipase C calmodulin pathway, and both tyrosineprotein kinase and protein kinase C activities are important in the transduction of the electrophysiological response.

TL;DR: Ligaments were found to creep distinctly less than would be predicted from relaxation tests, and it is speculated that this behaviour is due to the progressive recruitment of collagen fibres during creep.

TL;DR: It is indicated that the facet joints and Luschka joints are the major contributors to coupled motion in the lower cervical spine and that the uncinate processes effectively reduce motion coupling and primary cervical motion (motion in the same direction as load application), especially in response to axial rotation and lateral bending loads.

TL;DR: Shear stress increased nitric oxide production by chondrocytes, and the shear‐induced change in matrix macromolecule metabolism was influenced by nitricoxide synthesis, G protein activation, and phospholipase C activation.

TL;DR: The paraspinal muscles of patients who have low back pain display a more glycolytic (faster) profile; this can be expected to render them less resistant to fatigue.

TL;DR: The alterations in the physical properties of the articular cartilage after transection of the anterior cruciate ligament in the rabbit show trends similar to those observed in human and other animal models of osteoarthritis and provide further support for the use of this model in the study of cartilage degeneration.

TL;DR: The present studv supports the classic bending theory of Pauwels and demonstrates that the proximal lateral aspect of the femur is subjected to tension during the stance phase of gait.

TL;DR: An experimental model of lengthening of the lower limb was used to study the morphology and cellular proliferation of regenerating bone tissue after 20% lengthening at four rates of distraction and cell proliferation was increased at all of the higher rates studied.

TL;DR: Insulin‐like growth factor‐II is capable of stimulating cell proliferation and matrix metabolism in tendon explants of young rabbits at levels similar to those of insulin‐likegrowth factor‐I; in combination, the two growth factors are unable to augment the stimulatory effects of either of the factors alone.

TL;DR: It seems that degenerative changes at the supraspinatus insertion reduce the tensile strength of the tendon and constitute a primary pathogenetic factor of rotator cuff tear.

TL;DR: The results show that the extracellular matrix of knee meniscus varies continuously across its width in a manner consistent with increased compressive loading on the thinner, inside aspect of the structure.

TL;DR: Hydstatic pressure at physiologic levels enhances the expression of transforkming growth factor‐β mRNA in addition to increasing proteoglycan synthesis in chondrocytes and that excessively high hydrostatic pressure reduces theexpression of transforming growth factor-β1 mRNA and increases the expressionof heat shock protein 79 mRNA while decreasing proteogly can synthesis.

TL;DR: The response characteristics of carpal tunnel pressure to fingertip loading are revealed, which is one step in understanding the relationship between sustained grip and pinch activities and the aggravation or development of median neuropathy at the wrist.

TL;DR: The results showed that the kinetic measures were more reproducible than the kinematic measures, especially for abduction‐adduction and internal‐external rotation.