Density and Fat Fraction of the Psoas, Paraspinal, and Oblique Muscle Groups Are Associated With Lumbar Vertebral Bone Mineral Density in a Multi-Ethnic Community-Living Population: The Multi-Ethnic Study of Atherosclerosis.

Low vertebral bone mass is a major risk factor for vertebral compression fractures. Although sarcopenia has been shown to be associated with low bone mineral density (BMD), it is not known whether trunk musculature is directly associated with lumbar BMD, and whether exercise modifies this association. Using data from the Multi-Ethnic Study of Atherosclerosis (MESA), we sought to determine the association of muscle density and fat fraction of the psoas, paraspinal, and oblique muscle groups with L lumbar volumetric BMD, and whether these associations were modified by exercise.

Cell populations and muscle fiber morphology associated with acute and chronic muscle degeneration in lumbar spine pathology.

Many chronic musculoskeletal conditions are associated with loss of muscle volume and quality, resulting in functional decline. While atrophy has long been implicated as the mechanism of muscle loss in these conditions, recent evidence has emerged demonstrating a degenerative phenotype of muscle loss consisting of disrupted muscle fiber membranes, infiltration of cells into muscle fibers, and as previously describer, possible replacement of muscle fibers by adipose tissue. Here, we use human lumbar spine pathology as a model system to provide a more comprehensive analysis of the morphological features of this mode of muscle loss between early and late stages of disease, including an analysis of the cell populations found in paraspinal muscle biopsies from humans with acute vs chronic lumbar spine pathology.

Comparison of lateral lumbar interbody fusion (LLIF) with open versus percutaneous screw fixation for adult degenerative scoliosis.

Study Design: Retrospective Review.

Objectives: Compare clinical outcomes and radiographic correction of adult degenerative scoliosis (ADS) patients treated with lateral lumbar interbody fusion (LLIF), combined either with percutaneous (no laminectomy) versus open laminectomy/pedicle screw instrumentation.

Methods: Twenty-two ADS patients undergoing combined LLIF and posterior instrumentation were divided into two groups: thirteen patients underwent LLIF with laminectomy and posterior pedicle instrumentation (Group-1, six revision); nine patients underwent LLIF with percutaneous pedicle instrumentation (no decompression) (Group-2).

Lumbar multifidus muscle degenerates in individuals with chronic degenerative lumbar spine pathology.

Histological and cell-level changes in the lumbar musculature in individuals with chronic lumbar spine degenerative conditions are not well characterized. Although prior literature supports evidence of changes in fiber type and size, little information exists describing the tissue quality and biology of pathological features of muscle in this population. The purpose of this study was to quantify multifidus tissue composition and structure, inflammation, vascularity, and degeneration in individuals with chronic degenerative lumbar spine pathology.

Vasculopathy, Ischemia, and the Lateral Lumbar Interbody Fusion Surgery: Report of Three Cases.

Multi-modal neurophysiologic monitoring consisting of triggered and spontaneous electromyography and transcranial motor-evoked potentials may detect and prevent both acute and slow developing mechanical and vascular nerve injuries in lateral lumbar interbody fusion (LLIF) surgery. In case report 1, a marked reduction in the transcranial motor-evoked potentials on the operative side alerted to a 28% decrease in mean arterial blood pressure in a 54-year-old woman during an L3-4, L4-5 LLIF. After hemodynamic stability was regained, transcranial motor-evoked potentials returned to baseline and the patient suffered no postoperative complications.

Altered bioreactivity and limited osteoconductivity of calcium sulfate-based bone cements in the osteoporotic rat spine.

Background Context: Previous studies documenting the osteoconductive nature of calcium sulfate (CaSO(4))-based biomaterials have been largely limited to animal models exhibiting nonosteoporotic bone biology. In addition to diminished bone mineral density (BMD) and altered bone microarchitecture, the osteoporosis phenotype is associated with a proinflammatory and pro-osteolytic state. Thus, osteoporosis may elicit an amplified bioreactivity to common orthopedic biomaterials, potentially limiting their full osteoconductive capabilities in vivo.