Carol Muehleman

STUDY DESIGN: In vivo study of the effect of injection of osteogenic protein-1 (OP-1) on a rabbit anular needle puncture model of intervertebral disc (IVD) degeneration.

OBJECTIVE: To study radiographic, magnetic resonance imaging (MRI), biochemical, and histologic changes in the rabbit IVD after injection of OP-1 into the nucleus pulposus in a needle puncture disc degeneration model.

SUMMARY OF THE BACKGROUND DATA: Growth factors, such as OP-1, have the ability to stimulate synthesis of ...

STUDY DESIGN: In vitro studies of the effects of proinflammatory cytokines on the production of nerve growth factor (NGF) by human intervertebral disc (IVD) cells.

OBJECTIVE: To determine the constitutive expression and production of NGF and the effect of cytokines on the expression of NGF by human IVD cells.

SUMMARY OF THE BACKGROUND DATA: NGF may play a role in the collateral sprouting of sensory axons, neural survival, and regulation of nociceptive sensory neurons. NGF is known to be ...

STUDY DESIGN: An in vivo study to radiographically and histologically assess a new method of induction of disc degeneration. OBJECTIVE.: To establish a reproducible rabbit model of disc degeneration by puncturing the anulus with needles of defined gauges and to compare it to the classic stab model.

SUMMARY OF BACKGROUND DATA: New treatment approaches to disc degeneration are of great interest. Although animal models for disc degenerative disease exist, the quantitative measurement of ...

INTRODUCTION: The etiology of degenerative disc disease is unknown. Several investigators have reported the presence of proteolytic enzymes, such as the matrix metalloproteinase (MMP) and ADAMTS (a disintegrin and metalloprotease with thrombospondin-like repeats) families, in degenerated human discs. Glasson and colleagues recently reported that a significant reduction occurs in the severity of cartilage destruction in ADAMTS5 knockout mice compared with wild-type mice. The purpose of ...

BACKGROUND: We sought to determine whether symptomatic medial knee osteoarthritis is associated with aberrant loading across the foot during gait.

METHODS: Twenty-five individuals with medial knee osteoarthritis were compared with 25 controls. Knee radiographs and Western Ontario and McMaster Universities Arthritis Index questionnaires were obtained. Participants walked barefoot over pressure sensors, and the center-of-pressure trace was plotted against the axis of the foot, and a ...

STUDY DESIGN: In vitro studies on the effects of recombinant human growth and differentiation factor-5 (rhGDF-5) on matrix metabolism of bovine intervertebral disc cells and an in vivo study on the effect of rhGDF-5 in the rabbit anular puncture model.

OBJECTIVE: To determine the reparative capacity of rhGDF-5 on the intervertebral disc.

SUMMARY OF BACKGROUND DATA: The in vitro and in vivo effects of rhGDF-5, a crucial protein in the developing musculoskeletal system, on repair of the ...

STUDY DESIGN: In vivo histologic study of nerve ingrowth in the rabbit anular-puncture disc degeneration model.

OBJECTIVE: To examine innervation of intervertebral discs and surrounding tissues in the rabbit anular-puncture model with various magnitudes of injury.

SUMMARY OF BACKGROUND DATA: A rabbit anular-puncture model of disc degeneration was recently established. However, to our knowledge, the neuropathologic changes in the degenerated disc and surrounding tissues in this model have ...

STUDY DESIGN: In vivo study of the effect of an injection of recombinant human osteogenic protein-1 into degenerated discs induced by chondroitinase ABC.

OBJECTIVE: To investigate the efficacy of an injection of recombinant human osteogenic protein-1 to induce the recovery of disc height, and biochemical and histologic repair, in discs degenerated through enzymatic digestion by chondroitinase ABC.

SUMMARY OF THE BACKGROUND DATA: Chondroitinase ABC is currently proposed as a ...

OBJECTIVE: The purpose of this work was to test the effect of inhibition of bone remodeling, through the use of the bisphosphonate, zoledronic acid, on cartilage matrix damage in an animal model of cartilage matrix damage.

DESIGN: New Zealand white rabbits were divided into four groups for treatment purposes: (1) untreated controls; (2) injected into one knee joint with the cartilage matrix degradation enzyme, chymopapain; (3) injected into one knee joint with chymopapain and also given ...

Abstract: The prevalence of osteoarthritis (OA) is higher in some joints than in others. Fibrillation and full-thickness cartilage defects in the knee have been considered to be evidence of developing OA (pre-OA). While similar changes have been reported in the ankle (talocrural joint), the frequency of these changes is much higher than expected if the degeneration represents pre-OA. These observations suggest that in the ankle degenerative changes do not proceed to OA. The current study ...

OBJECTIVE: The zonal composition and functioning of adult articular cartilage causes depth-dependent responses to compressive injury. In immature cartilage, shear and compressive moduli as well as collagen and sulfated glycosaminoglycan (sGAG) content also vary with depth. However, there is little understanding of the depth-dependent damage caused by injury. Since injury to immature knee joints most often causes articular cartilage lesions, this study was undertaken to characterize the ...

We assessed the distribution and relative immunohistochemical staining intensity of the bone morphogenetic protein-7, osteogenic protein-1 (OP-1), in its pro- and mature forms, and four of its receptors, type I (ALK-2, ALK-3, and ALK-6) and type II in normal adolescent New Zealand White rabbit articular cartilage. Expression of the protein and its receptors was also examined in cartilage from joints that had been previously subjected to cartilage matrix degradation. Pro-OP-1 was ...

OBJECTIVE: To introduce a novel X-ray technology, diffraction-enhanced X-ray imaging (DEI), in its early stages of development, for the imaging of articular cartilage.

DESIGN: Disarticulated and/or intact human knee and talocrural joints displaying both undegenerated and degenerated articular cartilage were imaged with DEI. A series of three silicon crystals were used to produce a highly collimated monochromatic X-ray beam to achieve scatter-rejection at the microradian level. The third ...

Lipopolysaccharide (LPS) induces matrix degradation and markedly stimulates the production of several cytokines, i.e., interleukin-1β, −6, and −10, by disc cells and chondrocytes. We performed a series of experiments to compare cellular responses of cells from the bovine intervertebral disc (nucleus pulposus and annulus fibrosus) and from bovine articular cartilage to LPS. Alginate beads containing cells isolated from bovine intervertebral discs and articular cartilage were cultured with ...

Conventional radiography produces a single image of an object by measuring the attenuation of an x-ray beam passing through it. When imaging weakly absorbing tissues, x-ray attenuation may be a suboptimal signature of disease-related information. In this paper we describe a new phase-sensitive imaging method, called multiple-image radiography (MIR), which is an improvement on a prior technique called diffraction-enhanced imaging (DEI). This paper elaborates on our initial presentation of ...