Marrow fat may distribute the energy of impact loading throughout subchondral bone.

Most students of articular mechanics consider impact loads to be compressive forces that are borne by an intraosseous, trabecular scaffold. The possible role of marrow fat, which comprises about 75% of the structure, is generally ignored, and the potential contribution of type 1 collagen, the prototypic tensile protein, is not considered. Here, I question the evidence underlying these omissions and reject the conclusion of exclusive trabecular compression.

Impact-driven, pulmonary emboli of osseous fat in exercise-induced bronchospasm.

Exercise induced bronchospasm (EIB) affects approximately 10% of normal individuals with higher prevalence rates among children, obese adults, and competitive athletes. Although hyperpnea with dry air is the best known cause, the problem is multifactorial with atopy, asthma and chlorine all playing established roles. To date, no clear mechanism has connected musculoskeletal loading with the ensuing pulmonary compromise.

The human knee: A window on the microvasculature.

In synovial joints, the lining cells do not have tight junctions with their neighboring cells and they have no underlying basement membrane. Therefore, the synovial fluid within the articular cavity is continuous with the interstitial fluid of the synovial intima. These features, combined with ready access to the space via arthrocentesis, permit quantitative studies of microvascular function in the knees of unanesthetized, volunteer, human subjects both with and without chronic arthritis.

Prevalence of birefringent crystals in cardiac and prostatic tissues, an observational study.

Introduction: The prevalence of urate crystals in residual tissue samples from coronary arteries, aortic valves and prostate glands was assessed.

Methods: Alcohol-fixed coronary arteries from 55 explanted hearts, alcohol-fixed aortic valves collected from 75 valve replacement surgeries and 40 frozen, unfixed prostate specimens resected during cancer surgery were examined for birefringent crystals with polarising microscopy.

Results: In the 55 explanted hearts, 6 (10.

Uricosuric drugs: the once and future therapy for hyperuricemia?

Purpose Of Review: Although uricosuric agents provide the most time-honoured approach to the control of hyperuricemia, their place in the armamentarium has been eclipsed by that of xanthine oxidase inhibitors. This review considers the potential for uricosuric agents from the perspective of recent progress in the understanding of urate transport systems.

Recent Findings: No new agents have yet become available, but promising new drugs are under development.

Treatment of acute gouty arthritis in complex hospitalized patients with anakinra.

Objective: To report our experience with the efficacy and safety of anakinra for acute gouty arthritis in medically complex hospitalized patients.

Methods: We reviewed the hospital charts of 26 patients treated with anakinra for crystal-induced arthritis since 2007. Demographics, comorbid conditions, reason for anakinra use, response to treatment, and any adverse outcomes were recorded.

A perspective on diet and gout.

The epidemiology of gout has changed dramatically over the past century. Once thought of as a disease of the nobility, it is now an egalitarian disease that affects patients across the socioeconomic spectrum. The incidence of gout has also risen in recent years, to the point that we are now seeing what is regarded by some as a "second epidemic" of gout.

Pathways of microvascular permeability in the synovium of normal and diseased human knees.

Objective: Our study uses the entire proteomes of serum and synovial fluid (SF) to characterize the avenues of microvascular egress of plasma proteins, and quantifies that traffic in normal and diseased human knees.

Methods: Paired aliquots of serum and SF were collected from 17 knees of 11 subjects who died without evident joint disease and 16 patients with clinical effusions, fractionated by gel filtration chromatography and analyzed as continuous plots of the SF/serum concentration ratio versus molecular radius from 1 to 12 nanometers (nm). Curve-stripping methodology, a 3-pore model, and known protein kinetics were then applied to estimate the dimensions of and the net outflow through fenestral, "small," and "large" apertures in the microvascular endothelium.

A concise history of gout and hyperuricemia and their treatment.

First identified by the Egyptians in 2640 BC, podagra (acute gout occurring in the first metatarsophalangeal joint) was later recognized by Hippocrates in the fifth century BC, who referred to it as 'the unwalkable disease'. The term is derived from the Latin word gutta (or 'drop'), and referred to the prevailing medieval belief that an excess of one of the four 'humors'--which in equilibrium were thought to maintain health--would, under certain circumstances, 'drop' or flow into a joint, causing pain and inflammation. Throughout history, gout has been associated with rich foods and excessive alcohol consumption.

Epidemiology of hyperuricemia and gout.

Gout is an increasingly common medical problem. The traditional risk factors of male sex and high red meat or alcohol consumption have been joined by a wave of newer risk factors, such as increased longevity, the metabolic syndrome (hypertension, diabetes, dyslipidemia, truncal obesity, increased cardiovascular disease risk), use of diuretics, low-dose aspirin, or cyclosporine, and end-stage renal disease. Atypical presentations of gout in the elderly can mimic osteoarthritis and rheumatoid arthritis.

Bone pain and pressure in osteoarthritic joints.

Intraosseous hypertension has been associated with a deep aching bone pain, particularly at rest, in subsets of patients with osteoarthritis of the hip and knee. The pathophysiology of this problem remains uncertain, but intraosseous phlebography implicates outflow impairment at relatively distal venous sites. Although the issue has been controversial, intraosseous pressures rise normally, and painlessly, when epiphyseal bone is loaded and these pulses may be mechanically meaningful in the distribution and transmission of impact energy.

Spinal degenerative disk disease (DDD) in female macaque monkeys: epidemiology and comparison with women.

Spinal degenerative disk disease (DDD) in a radiographic, cross-sectional sample of 192 female macaque monkeys, approximately 5-30 years old, is described. The presence and extent of disk space narrowing (DSN) and anterior osteophytosis were assessed with reference to age, average lifetime body mass. and distribution within the thoracolumbar spine.