Bone & Joint Pathology

The term arthritis literally means joint inflammation and has been generalized to include inflammations of the joints themselves as well as their surrounding structures. There are at least 25 different diseases that come under the heading of arthritis, including the various forms of rheumatoid arthritis, osteoarthritis, gouty arthritis, and septic arthritis. Inflammations of the bursa and tendons around joints are called bursitis and tendinitis.
Probably the most debilitating form of arthritis is rheumatoid arthritis (RA). It comes in juvenile and adult varieties and its effects may be general or specific. In any case RA is a systemic disease of joint connective tissue, which results in inflammation to the joint accompanied by pain, swelling, and loss of function. In the first stage of RA the synovial membrane becomes inflamed. Synovial fibroblasts respond with the random production of collagen, which interferes with the process of synovial fluid replacement, which results in the pain and tenderness associated with increased synovial pressure. In the second stage, connective tissue production spreads to articular surfaces, covering the articular cartilage with a layer of tissue called the pannus. The pannus interferes with the nutrient supply to the cartilage, and the cartilage degenerates. In the third stage, with the destruction of articular cartilage, a connective tissue bridge is formed from bone to bone. Eventually the bridge becomes ossified and the bones of the joint are fused.
Osteoarthritis is a condition in which the articular cartilage degenerates to the point where parts of the articular surfaces of the bone become directly exposed to the joint cavity. Osteoblasts along the surface of the bone respond by manufacturing more osseous tissue at the site, which leads to the formation of bone spurs. The spurs interfere with movement of the joint, are painful, and in some cases break off into the synovial cavity.
Gouty arthritis is a condition in which uric acid combines with sodium to produce sodium urate crystals, which find their way to various connective tissue sites including the outer ears and the joints of the distal extremities (hands and feet). The crystals interfere with the movement of the joints and eventually destroy the tissues. Gout can be treated both chemically and dietetically with success. Injections of colchicine reduce the occurrence of the crystals, and reducing the intake of high-purine foods reduces the production of uric acid.

Septic arthritis is an infection of a synovial joint. It may be bacterial, viral, or fungal in origin. The pyogenic (bacterial) form may be caused by staphylococci, streptococci, pneumococci, or other bacteria and is most common in cases of intravenous drug use.

Bursitis is an acute or chronic inflammation of bursae.
Tendinitis is an inflammation of tendon sheaths and synovial membranes.

A dislocation, or luxation, is a displacement of a bone from its joint; a partial dislocation is called subluxation.
A sprain is the forcible wrenching or twisting of a joint with partial rupture to its attachments without dislocation, while a strain is the stretching of a muscle.

Growth Plates

APPROXIMATE AGES OF GROWTH PLATE (EPIPHYSEAL) CLOSURES
Spinal Column
Vertebrae and sacrum    25
Trunk
Sternum    25
Ribs        25
Upper Appendages
Clavicle    25
Scapula    15-17
Humerus
Head fused with shaft    20
Lateral epicondyle    16-17
Medial epicondyle    18
Ulna
Olecranon    16
Distal end    20
Radius
Head and shaft    18-19
Distal end    20
Lower Appendages
Pelvic bone
Inferior rami    7-8
Acetabulum    20-25
Femur
Greater and lesser trochanters    18
Head    18
Distal end    20
Tibia
Proximal end    20
Distal end    18
Fibula
Proximal end    25
Distal end    20

Parts of a typical long bone include the periosteum and articular cartilage, the epiphyses (ends) and diaphysis (shaft), and the medullary or marrow cavity. The dense fibrous connective tissue of the periosteum covers the entire surface except, for the articular surfaces, which are covered with hyaline cartilage. A cut through the diaphysis reveals an outer collar of compact bone separated from the porous spongy bone of the interior by an inner layer of bone called the endosteum. The pores within the spongy bone contain a rich blood supply that forms the red marrow, where blood cell formation takes place. At the center of the bone is the medullary cavity. The medullary cavity is largely filled with stored adipose that forms the yellow marrow.

SKELETAL MUSCLE is no mystery

Skeletal Muscle Function
The basis for all muscle function is the unique ability of muscle tissue to contract, that is, to generate a pulling force from both ends towards its center.

Muscles are attached to bones, and bones act as levers in order to do work.  A lever is defined as a rigid rod that moves about on some fixed point called a fulcrum.  Joints act as the fulcrum.  Therefore, when muscles contract they move bones about their joints.

The movement that the contracting muscle produces – flexion, extension, abduction, adduction, rotation – is determined by two factors: the type of joint it spans (ball and socket, hinge, pivot, etc.), and the relation of the muscle’s line of pull to the center of the joint (the fulcrum).  Line of pull is the averaging of all the fibers of a muscle into a single line of force.
For instance, because the hip is a ball and socket joint (multiaxial), any muscle whose line of pull crosses lateral to the joint will abduct the joint.  That is, it will move the thigh laterally.  On the other hand, a muscle that crosses lateral to the elbow joint (a hinge joint) cannot cause it to abduct because the elbow can only flex or extend.

All skeletal muscles are attached by tendons to at least two bones and span at least one joint.  One attachment is the origin, and the other is the insertion.  The origin is generally on the more stable of the two bones, and is usually the most proximal of the two attachments.  It is characterized by stability and closeness of the muscle fibers to the bone.  The insertion is on the least stable of the two bones, and is usually the distal attachment.  It frequently involves a relatively long tendon, and the bone into which the muscle’s tendon inserts is ordinarily the one that moves.

Arthrology: understanding joint function

Arthrology: Joints and  Articulations… A joint or articulation is a point of contact between two or more bones.
When classifying anything in anatomy and physiology, we can look at two aspects: Function and Structure.
So it comes as no surprise that joints are classified functionally and structurally.

FUNCTIONAL: Looks at the move ability of the joint.
1.    SYNARTROSES:  immovable  joints
2.    AMPHIARTHROSES:  slightly movable joints
3.    DIARTHROSES:  freely movable joints

Structural: Looks at how they are made, the building blocks.
1.    FIBROUS: Have no joint cavity, and the bones are held together by a thin layer of fibrous tissue.
a.    Suture - articulating bones separated by a thin layer of fibrous tissue.
Movement: Slightly (amphiarthrotic)
b.    Syndesmosis – articulating bones united by dense fibrous tissue.  Ex: Distal ends of the tibia and fibula.
Movement: Slight (amphiarthrotic)
c.    Gomphosis – a cone shaped peg that fits into a socket; articulating bones separated by periodontal ligament.  Ex: Roots of teeth in the alveolar processes.
Movement: Slightly (amphiarthrotic)

2.    CARTILAGINOUS: Has no joint cavity, and the articulating bones united by cartilage.
a.    Synchondrosis – Connecting material is hyaline cartilage.  Ex: Temporary joint between the diaphysis and epiphyses of a long bone.  These are our growth plates.
Movement: None (synarthrotic)
b.    Symphysis – Connecting material is a broad, flat disc of fibrocartilage.
Movement: Slight (amphiarthrotic)

3.    SYNOVIAL: These have a joint cavity, filled with synovial fluid, and articular cartilage present, and the  articular capsule is composed of an outer fibrous capsule and an inner synovial membrane. May contain necessary ligaments, articular discs (menisci), and bursea.
Movement: Freely movable (diarthrotic) These are the only free moving joints in the body, and are the joints associated with movement.

It is Not Enough David Whyte

It is not enough to know.
It is not enough to follow
the inward road conversing in secret.

It is not enough to see straight ahead,
to gaze at the unborn
thinking the silence belongs to you.

It is not enough to hear
even the tiniest edge of rain.

You must go to the place
where everything waits,
there, when you finally rest,
even one word will do,
one word or the palm of your hand
turning outward
in the gesture of gift.

And now we are truly afraid
to find the great silence
asking so little.

One word, one word only.

Male Reproductive System

Male Reproductive System
The male reproductive system is a series of organs located both outside of the body and within the pelvic region. The primary direct function of the male reproductive system is to provide the male gamete or spermatozoa for fertilization of the ovum, however it also serves as an endocrine gland .
The major reproductive organs of the male can be grouped into three categories. The first category is sperm production and storage. Production takes place in the testes, which are housed in the temperature regulating scrotum, immature sperm then travel to the epididymis for development and storage. The second category are the ejaculatory fluid producing glands which include the seminal vesicles, prostate, and the vas deferens. The final category are those used for copulation, and deposition of the spermatozoa (sperm) within the female, these include the penis, urethra, vas deferens, and Cowper’s gland. An important sexual hormone of males is androgen, and particularly testosterone.
Testes are components of both the reproductive system (being gonads) and the endocrine system (being endocrine glands). The functions of the testes are: producing sperm (spermatozoa) & producing male sex hormones, (testosterone is the most common).
Sperm are haploid cells, (it’s 23 chromosomes can join the 23 chromosomes of the female egg to form a diploid cell). These uniflagellar sperm cells are motile, have a limited life span (3 days), and cannot divide.  After fusion with egg cells during fertilization, a zygote is formed with the potential to develop into a new organism.
These spermatozoa are produced through spermatogenesis inside the male gonads (testicles) via meiotic division. They are carried out of the male body in a fluid known as semen
Prostate is an exocrine gland of the male reproductive system. The function of the prostate is to store and secrete a slightly alkaline (pH 7.29) fluid that usually constitutes 25-30% of the volume of the semen along with spermatozoa and seminal vesicle fluid. The alkalinity of semen helps neutralize the acidity of the vaginal tract, prolonging the lifespan of sperm. The prostate also contains some smooth muscles that help expel semen during ejaculation.

Testosterone

Testosterone is a steroid hormone from the androgen group. In men, testosterone plays a key role in health and well-being as well as preventing osteoporosis. On average, an adult male produces about forty to sixty times more testosterone than an adult female. Testosterone effects include growth of muscle mass and strength, increased bone density, stimulation of growth and bone maturation. Time targeted effects include maturation of the sex organs, a deepening of the voice, growth of the beard and axillary hair. Many of these fall into the category of male secondary sex characteristics.

Marianne Williamson Our Deepest Fear

Our deepest fear is not that we are inadequate. Our deepest fear is that we are powerful
beyond measure. It is our light, not our darkness that most frightens us. We ask ourselves, Who
am I to be brilliant, gorgeous, talented, fabulous? Actually, who are you not to be? You are a child
of God. Your playing small does not serve the world. There is nothing enlightened about
shrinking so that other people won’t feel insecure around you. We are all meant to shine, as
children do. We were born to make manifest the glory of God that is within us. It’s not just in
some of us; it’s in everyone. And as we let our own light shine, we unconsciously give other
people permission to do the same. As we are liberated from our own fear, our presence
automatically liberates others.

Sweet Darkness David Whyte

Sweet Darkness
When your eyes are tired
the world is tired also.

When your vision has gone
no part of the world can find you.

Time to go into the dark
where the night has eyes
to recognize its own.

There you can be sure
you are not beyond love.

The dark will be your womb
tonight.

The night will give you a horizon
further than you can see.

You must learn one thing:
the world was made to be free in.

Give up all the other worlds
except the one to which you belong.

Sometimes it takes darkness and the sweet
confinement of your aloneness
to learn
anything or anyone
that does not bring you alive

is too small for you.