Week 2 Osteo&Artho Joints and skull

Viscerocranial bone (Facial bones )

zygomatic, maxilla, nasal, lacrimal, mandible, sphenoid is both _____________ and neurocranial

cartilaginous joints

partially movable such as vertebrae and some cranial sutures Classified by type of material or manner bones are united _________________ joints are those in which the bones are connected by cartilage -Synchondrosis: the bones are joined by hyaline cartilage. Synchondrosis are found in the epiphyseal plates of growing bones in children -Symphyses : hyaline cartilage covers the end of the bone, but the connection between bones occurs through fibrocartilage. Symphyses are found at the joints between vertebrae and between the pubic (symphyses) bones

Wormian bones

AKA intra sutural bones are extra bone pieces that occur within a suture in the cranium Irregular isolated bones that appear in addition to the usual ossification centers of the cranium and -Unusual but not rare They occur most frequently in the Lambdoidal suture , which is more tortuous than other sutures. -occasionally within the sagittal and coronal sutures Usually found in children before the sutures start to close Not usually considered abnormal unless there are 10 or more May indicate certain types of pathology

Joints of the Adult Skull

According to most anatomy texts the joints of the adult skull are fibrous sutures. However this is not the case Most sutures of the cranium remain at least semi movable well into adulthood so rather than synarthrosis most chiropractors and osteopaths consider cranial joints to be synchondrosis***** -Squamous suture (last to ossify) -Basilar suture

Neurocranium

Consists of 8 bones -Four singular- frontal, ethmoid, occipital, sphenoid -2 paired bones (eight total)- parietal, temporal Roof-Calveria (skull cap)-frontal, temporal (paired) and occipital bones Floor- Cranial Base- sphenoid, temporal, a small portion of the ethmoidal Some are pneumatized bones (contain air spaces) aka. sinuses -Frontal, ethmoid, temporal, sphenoid ethmoid -Decrease weight (these bones are light in weight and their strength has been minimized)

Joints of the Cranium Major Sutures

Coronal-between the frontal(1)anteriorly and parietals(2)posteriorly Sagittal-midline between the parietals(2) Lambdoidal-between the parietals(2)anteriorly and the occipital(1) posteriorly Squamosal(2)-between the temporal and parietal bones bilaterally Metopic-found in frontal bones in infant Basilar-cartilaginous-(1)-between anterior of basilar portion of occiput and posterior of sphenoid.

Movement of the joints of the skull

In the mid '70s John Upledger proved that the sutures moved of the skull 100th of an inch and contained blood vessels, nerve fibers and connective tissues Upledger and his research team from the Michigan State University studied fresh cadavers using electron microscopes, radio waves and cinematographic X-rays to prove that the cranial bones moved John Upledger stated When fusion occurs in the skull it is a pathological condition resulting from a trauma that has interfered with normal joint mobility and function -He considered this arthritis. -Arthritis will occur in any joint in the body that has been damaged from trauma and remains subluxated and/or fixated Multiple chiropractic techniques use cranial adjusting Further evidence -Age of a post-mortem skull is determined by the movability of the sutures Evidence shows some sutures remain movable though out your entire life

Articulation of Cranial bones

Most bone of the Neurocranium do not articulate with each other at birth -Fontanels (soft spots on babies head)-anterior, posterior, sphenoid and mastoid Articulations between mature cranial bones are called sutures

Cranial Buttresses

Pillars formed by thickened cranial bones that allow forces to by pass the orbits and nasal cavity-Bones are thinner in these areas Viscerocranium -Nasomaxillary -Zygomaticmaxillary Masticatory plates-mandible and maxillary bones for tooth articulation -Pterygomaxallary -Vertical mandible Neurocranium -Occipital -Also tries into buttresses formed by the Viscerocranium bones that have sinuses are weaker therefore, larger bones (_____________ support and protect them)

Condyloid Joints

Similar to gliding joints, _______________ joints are somewhat different in that they have an irregular surface where the bones move past one another. This type of joint is like two bowls nested together ex metacarpophalangeal joints of the hand and radio-carpal joint of the wrist

Viscerocranium

Some overlap with Neurocranium Makes up the facial bones some, paired others not -nasal, lacrimal, zygomatic, maxillary, ethmoid (shared with neurocranium), inferior nasal conchae, palatine, vomer, mandible (not always considered a cranial bone) (facial area) maxillary, ethmoid contain air cells (sinuses) Multiple openings, elevations and depressions -Nerve artery vein muscle passage Some Viscerocranium bones articulate with Neurocranium bones to form structures -Zygomatic arch (zygomatic and temporal) -Orbit -Nasal cavity

Cleidocranial dysotosis

affects growth of clavicles facial bones and teeth (Pathologies associated with Wormian bones)

hypothyroidism

decreased metabolic function (Pathologies associated with Wormian bones)

diarthrosis joints

freely movable (synovial joints used in body movement) Classified by functional use

rickets

soft bones (Pathologies associated with Wormian bones)

down's syndrome

chromosomal disorder (Pathologies associated with Wormian bones)

pivot joints

is a joint in which rotational motion occurs without gliding movement. This type of joint allows for turning motions without sideways displacement or bending. Ex joint between the first and second cervical vertebrae (atlas-axis) and proximal ends radius and ulna

hinge joints

as the name implies, are hinged joints formed between two bones. A _________ joint allows for stable flexion and extension without sliding or deviation. Ex. The elbow joint between the humerus and ulna

Gliding Joints (AKA Plane Joint)

allow for smooth movement in several directions along a plane or other smooth surface. The articulation is like two plates sliding across each other. Ex. the carpal bones of the wrist (action), which form a ___________- synovial joint

ball and socket joint

allow for stable movement in several directions without slippage. Like a saddle joint, the _____ and _______ joint allows bending in several directions without slipping, creating a highly stable, strong joint. Ex hip joint (femur-acetabulum)

saddle joints

are characterized by two bones that fit together in a manner similar to a rider in a ___________. This sort of articulation allows bending motion in several directions without sliding. Ex. carpal-metacarpal joint of the thumb

Cranium

is divided into two portions -Neurocranium- surrounds the brain (protects the brain) --Formed from mesenchyme for the neural crest -Viscerocranium -face --Formed from mesenchyme from the pharyngeal arches -Some cranial bones are part of both the Neurocranium and Viscerocranium Skull contains the mandible, ____________ does not

synovial joints (diarthrosis)

Freely movable such as knee and finger joints. Classified by type of material or manner bones are united _______________ joints are the only joints that have a space between the adjoining bones . This space is referred to as the synovial (or joint) cavity -filled with __________ fluid _____________ fluid lubricates the joint, reducing friction between the bones and allowing for greater movement. The ends of the bones are covered with articular cartilage -hyaline cartilage we are going to love these joints, there is a space between these joints the __________________ fluid allows for free movement, similar to the concept of hydroplaning in a car on the road hyaline cartilage is another name for articular cartilage in weight baring regions there is also ________ The entire joint is surrounded by an articular capsule composed of connective tissue -This allows movement of the joint and resists dislocation. -Articular capsules may also possess ligaments that hold the bones together _____________ joints are capable of the greatest movement of the three structural joint types -the more mobile a joint, the weaker the joint*** Knees, elbows, and shoulders are examples of synovial joints 6 types of this joint Gliding joints, condyloid joints, saddle joints, hinge joints, ball and socket joints, pivot joints

Cranial Base

Three different sections at different levels -Anterior cranial fossa --Frontal bone, ethmoid bone, lesser wing and the body of the sphenoid bone --Shallowest -Middle cranial fossa --The sphenoidal crest of the lesser wing-anterior --The superior crest of the petrous potion of the temporal bone-posterior --Contains potions of the temporal and sphenoid bones Posterior cranial fossa -Mostly the occipital bone -Dorsum sellae, petrous and mastoid portion of the temporal-ant -Deepest

osteogenesis imperfect

brittle bone disease (Pathologies associated with Wormian bones)

hypophosphatasia

genetic affects bone mineralization (Pathologies associated with Wormian bones)

Menke's syndrome

genetic condition that affects copper storage "brittle hair disease" (Pathologies associated with Wormian bones)

Fibrous joints

immovable or partially movable such as sutures in the skull Classified by type of material or manner bones are united The bones of _____________ joints are held together by fibrous connective tissue. There is no cavity, or space, present between the bones 3 types: -Sutures are found only in the skull and possess short fibers of connective tissue that hold the skull bones tightly in place -Syndesmoses are joints in which the bones are connected by a band of connective tissue, allowing for more movement than in a suture ex: tibia and fibula in the ankle -Gomphoses occur between teeth and their sockets

synarthrosis joints

permits little or no mobility -Fibrous Classified by functional use

synchondrosis joints

permits slight mobility (mostly cartilaginous joints as with vertebrae and some cranial sutures ) Classified by functional use