Wednesday, April 29, 2009

Design Differences! Not all motors are the same!

 Apr 27 
Carey Lowery, 55nine Client and long time Wobble Naught user, takes the win at the NUE opener.  Carey stormed to a win at the Cohutta 100 in Ducktown, TN this weekend under blue skies and hot temps.  After the race Carey told 55nine fitter, Eddie O'Dea, that all she focused on during the many climbs of the race was her "pedal stroke and keeping xxxx xxxx relaxed."  When you practice the fundamentals, the rest takes care of itself.  Also on the podium was, Emily Brock, another 55nine Performance client who has been gaining strength since a back injury last year.  Congrats to both ladies and keep working on the fundamentals.

1st Carey Lowery Outdoor Store - 55nine Performance
2nd Paula Burk 
3rd Daniel Musto
4th Betsy Shogren
5th Emily Brock - Faster Mustache - 55nine Performance 

I know there was a few WN users on the men's podium as well......Jeremiah Bishop 2nd & Sam Korber was top 10.  Waiting for results there.  I had a flat within the first 5 minutes and entered the woods in 110th place!  Talk about bad starts.

Eddie O'Dea
55nine Performance

Articular hyaline cartilage
You can find basic info on cycling, but here is one you might not understand.  No two people have the same cartilage in the knee, it is not uniform and varies from younger to older!

Think about where the forces are a

nd this will start to make sense why we measure you the way we do it. The focus today is on the knee.

The articular surface of the distal femur, the articular surface on the posterior aspect of the patella and the articular surfaces on the tibial plateau are covered by a variety of hyaline cartilage termed articular hyaline cartilage. In a healthy person, articular hyaline cartilage offers a firm, smooth and relatively friction-free surface facilitating joint movements. The thickness of articular hyaline cartilage in the knee is not uniform and varies from 3 mm to 7mm. Articular hyaline cartilage possesses a degree of compressibility and elasticity. These features enable the articular surfaces to dissipate laterally the vertical compressive forces to which the knee joint is subjected during weight transmission and deep compression of the knee, semi weight bearing as sitting on a saddle.  

Articular hyaline cartilage does not usually ossify.

The surface of articular hyaline cartilage is lubricated by synovial fluid secreted by the synovial membrane lining the inner surface of the joint capsule. However, the articular cartilage itself is not covered by synovial membrane. As with hyaline cartilage in extraarticular sites, the substance of articular hyaline cartilage is made up of cells termed chondroblasts and chondrocytes, and an intercellular matrix elaborated by the chondrocytes. The intercellular matrix is biochemically complex, and is composed of various proteins including different types of collagen, a variety of cell adhesion molecules and glycosaminoglycans, and lipids. The glycosaminoglycans are arranged systematically about a core protein to form complex hydrophilic molecules termed proteoglycans. The proteoglycans are chiefly responsible for the impressive viscoelastic biomechanical properties of articular cartilage.

Healthy articular hyaline cartilage in the young individual has a pale and glistening appearance, and a firm and smooth texture. With age and weight degenerative changes begin to appear, and cartilage loses its smooth and glistening character.  Think sand-paper!

At the histological level, articular hyaline cartilage is seen to be made up of four layers or zones on the basis of differences in cellular morphology, cellular density as well as differences in the composition of extracellular matrix.

Of the four layers, the most superficial layer faces the joint cavity, and the deepest layer is apposed to, and fused with, the subchondral bone.

From superficial to deep, these layers are named as follows:

i) Tangential stratum (Zone 1).

ii) Transitional stratum (Zone 2).

iii) Radiate stratum (Zone 3).

iv) Calcified stratum (Zone 4).

The region between Zone 3 and Zone 4 is called the tidemark and is readily discernible in young cartilage. The progressive ossification of Zone 4, which accompanies aging, results in the blurring of the tidemark.  That means the compression rates are very different for a younger person vs. an aging person.

Articular hyaline cartilage is devoid of innervation and lymphatic vessels. Except for the presence of a few blood vessels in Zone 4, articular hyaline cartilage is also normally devoid of vascularity, and is believed to derive its nutrition mainly by diffusion from synovial fluid and from the vascular plexus in synovial membrane.

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