Adv Anat Unit 1

Sagittal Plane

divides the body into left and right sides

Frontal plane

divides the body into anterior and posterior portions

Transverse plane

divides the body into superior and inferior portions

Movement in the sagittal plane

rotates around the mediolateral axis

Movement in the frontal plane

rotates around the anteroposterior axis

Movement in the transverse plane

rotates around the longitudinal axis

Movement and planes

To confirm what plane a certain movement occurs in, imagine that plane is made of two pieces of glass and placed around your body. Can you make the certain movement between the two pieces of glass? If you can, then you know you are in the right plane for that movement!

Rotational movement occurs

In a plane rotating about an axis

Mediolateral axis

Runs side to side or medial/lateral. (Imagine an arrow going through one arm and pointing out the other)

Anteroposterior axis

runs front to back or anteroposteriorly. (Imagine an arrow going through the stomach and coming out through the back)

Longitudinal axis

Runs top to bottom or longitudinally (Imagine an arrow going through the top of the head and coming out through the foot)

Rotational movements

feature moving points of the object that do not all travel equal distance or velocity. (proximal elbow travels less distance than the distal hand during elbow flexion)

Translational movements

uniformly move. (walking forward or a skier sliding down a mountain)

Deformities in the Frontal Plane

The bone or bones will abnormally be more lateral or medial. Valgus is when the distal end of the bone is more lateral than usual relative to the midline. Varus is when the distal end of a bone is more medial than usual relative to the midline.

Deformities in the Sagittal plane

Includes recurvation which is excessive bowing posteriorly and antecurvation which is excessive bowing anteriorly.

Deformities in the Horizontal plane

rotational deformities or “twists” in bones. Retroversion is rotated posteriorly and anteversion is rotated anteriorly.

Kyphoses

Vertebral curvature that is concave anteriorly. Includes thoracic and sacral curves

Lordoses

Vertebral curvature that is concave posteriorly. Includes cervical and lumbar curves

Scoliosis

Excessive vertebral curvature from side to side

Differences between the Male and Female pelvis

The female ilia are laterally flared to provide a wider pelvis, the female pelvis inlets are wider and oval while the male inlets are somewhat heart shaped, the subpubic angle in the female is wider (greater than 90 degrees)

Pelvic Inlet

opening in the pelvis whose physical boundaries are defined by the pelvic prim

Pelvic Outlet

inferior to the pelvic inlet, boundaries are defined by the coccyx, ischial tuberosities, and the inferior border of the pubic symphysis

Subpubic angle

Femoral Angles

Angle of Inclination, Q Angle, Torsion Angle

Angle of Inclination

Is the angle of the head/neck of the femur in relation to the shaft. Is normally between 120-130 degrees. This angle is greatest at birth and diminishes with age. Angle is less in females due to the increased width of hips and increased Q angle of the femur.

Q Angle

Angle between the vertical line through the midpoint of the patella and the oblique line connecting the midpoint of the patella to the anterior superior iliac spine. Is normally 8-10 degrees for males and up to 15 degrees for females. This angle is not always the same on both sides. Excessive Q angles are likely to increase risks of patellofemoral pathology.

Angle of Torsion

The twist of the femur. The head and neck of the femur are not perfectly aligned with the condyles, they are at an angle to each other. Normal angle is between 7-15 degrees.

Excessive anteversion

Angle of torsion greater than 15 degrees. result in toe gait

Retroversion

angle of torsion is less than 7 degrees. results in toe our gait

Pelvic girdle weight transfer

1. Weight is transferred down the vertebral column 2. At the sacrum, the weight is split and transferred down the arch to the femurs. 3. The neck of the femur transfers the weight down the main body of the femur. 4. The pubic bone acts as a strut to brace the pelvis and support the arch. 5. Femoral anatomy allows for bipedal stance

Valgus

the distal element of the bone is more lateral than normal

Varus

the distal element of the bone is more medial than normal

Coxa Vara

distal femur is more medial than average, femoral angle of inclination is decreased (less than 120 degrees)

Coxa Valga

the distal femur is more lateral than average, femoral angle of inclination is increased (greater than 140 degrees)

Genu varum

distal tibia is more medial than average, this is normal until 18-24 months of age

Genu valgum

distal tibial is more lateral than average, common from 2-11 years old

Humeral Angles

Inclination, Torsion

Humeral Inclination

The angle between the axis of the head/neck of the humerus and the anatomical axis of the humeral shaft. Is usually around 135 degrees

Humeral Torsion

The twist of the humerus. The angle between the axis of the head/neck of the humerus and the inter-epicondylar axis. Averages around 20 degrees so it is considered retroversion. Allows the head to of humerus to better align with the scapula that sits on a slanted thoracic cage. At birth its as high as 60 degrees but decreases during childhood. Overloading the shoulder in youth can reduce the normal rotation during development (ex: elite baseball players)

Upper Limb Carrying Anlge

Formed by the interception of the dashed lines shown running through the humerus and ulna as the elbow is fully extended. Normal ranges are between 10-15 degrees. The carrying angle influences how objects are held by individuals. Those with a more extreme carrying angle may be more likely to pronate the forearm when holding objects in the hand to keep the elbow closer to the body

Relationship between Joint Mobility and Joint stability

The more mobile a join it, the less stable. The more stable a joint it, the less mobile

Classification of joints

Joints are classified by structure (the connective tissue involved in the binding of the 2 bones) and function (the relative degree of mobility between the 2 bones). Structure determines function

What types of joints are classified by structure?

Fibrous, Cartilaginous, synovial

Fibrous

Bones held together by dense regular connective tissue

Cartilaginous

bones held together by cartilage

Synovial

bones separated by a fluid-filled cavity which is enclosed by a capsule and stabilized by ligaments MOST COMMON AND FOCUS IN THIS CLASS

What Joins are classified by function?

synarthrosis, amphiarthrosis, diarthrosis

Synarthrosis

an immobile joint

Amphiarthorsis

a slightly mobile joint

Diarthrosis

a freely mobile joint MOST COMMON AND OUR FOCUS IN THIS CLASS

Articular Capsule of synovial joint

double layer that surrounds the entire joint

Synovial Membrane of Synovial Joint

Lines the inner capsule

Synovial Plicae of synovial joint

folds in the synovial membranes of large capsules like the knee and elbow that increase the surface area and allow for full joint motion without stressing the capsule

Joint cavity of synovial joints

a physical space separating the two articulating bones filled with synovial fluid

Synovial fluid of Synovial Joint

fluid inside the joint cavity

Articular cartilages of Synovial Joints

hyaline cartilage lining the appositional surfaces of the articulating bones

Synovial Joint

Ligament

connect bone to bone to maintain integrity of joint within normal range of motion. arranged in a variety of direction to withstand forces in multiple directions. strengthens most synovial membranes

Bursae

Fluid filled sacs that cushion and reduce friction in tight spaces

Tendon Sheaths

Fluid filled sacs that cushion and reduce friction in tight spaces

Types of Synovial Joints

Uniaxial, biaxial, multiaxial

Uniaxial

bone moves in one plane. (plane, hinge, pivot)

Biaxial

bone moves in two planes (condylar, saddle)

Mutliaxial

bone moves in more than two places (ball and socket)

Gliding Joint

Uniaxial. Movement in plane surface. Glide happens in two directions. (Intercarpals, intertarsals, acromioclavicular)

Pivot Joint

Uniaxial. Rotation around longitudinal axis. (Atlanto-axial joint, radiohumeral)

Hinge Joint

Uniaxial. Flexion and extension only (humeroulnar, interphalengeal)

Modified Hinge/bicondylar Joint

Uniaxial and Biaxial. Flexion, extension