Anatomy > Articulations (Joints) > Flashcards
Articulations (Joints) Flashcards
Flexion
- generally a decrease in the angle between anterior surfaces of bones - exception - knee and toes.
Dorsiflexion
- Moving the dorsum of the foot toward the anterior leg
Planterflexion
- Moving the plantar surface of the foot away from the leg
Extension
- increase in angle between anterior surfaces - (same exceptions as for flexion definition) - Generally restores structure to its anatomical position.
Hyperextension
- continuation of extension beyond anatomical position. More commonly used to describe extension beyond normal range of motion. Clinically reserved for injury.
Abduction
- usually movement of bone away from the midline of the body - exceptions are the digits of extremities.
Adduction
- usually movement toward midline.
Rotation
- movement of bone around its long axis (spin)
medial rotation - anterior surface moves toward midline
lateral rotation - anterior surface moves away from midline
Circumduction
- distal end moves in circle while proximal end remains stable - may partly involve flexion, abduction, adduction, extension and rotation.
Inversion
- movement of sole of foot inward (medially)
Eversion
- movement of sole of foot outward
Protraction
- thrusting jaw anteriorly
Retraction
- returning protracted part (pulling jaw back)
Supination
- movement so palms face anteriorly
Pronation
- movement so palms face posteriorly
Elevation
- part of body moves upward (hyoid bone in swallowing)
Depression
- movement downward (depress mandible when open mouth)
Opposition
- movement of anterior surface of thumb to face anterior surface of fingers
Articulation - Joint
- point of contact between bones
* because of many different bones in body and many different functions for these bones - many different joint types
3 types of Joint by functional classification
A. synarthroses - immovable joints
B. amphiarthroses - slightly movable joints
C. diarthroses - freely movable joints
Structural Classification: Fibrous Joints (What, examples)
- no joint cavity - bones joined by fibrous connective tissue
- permit little or no movement
- examples:
a. Sutures in skull - bones are united by a very thin layer of fibrous C.T. - these are synarthroses joints
b. distal articulation of tibia and fibula. - is slightly moveable - thus amphiarthrotic.
c. articulations of the roots of the teeth with maxillae and mandible - synarthrotic joints
Structural Classification: Cartilaginous Joints (What, 2 details)
- where bones are connected by cartilage - tight - little or no movement
- 2 kinds:
1. Synchondrosis - connecting material is hyaline cartilage - synarthrotic (immovable)
- example: epiphysial plate in long bones or junction between ribs and sternum
note – ep. plate will become replaced by bone when growth ceases thus becoming a synostosis (joint all bone).
2. Symphysis - connecting material = fibrocartilage disc. - found between vertebral bodies and symphysis pubis
- amphiarthrotic (slightly moveable)
Structural Classification: Synovial Joints (8 details)
- articulations with a synovial or joint cavity.
- no tissue interconnects bones - free to move - thus diarthrotic
- have articular cartilage - covers surfaces in articulation area but does not connect bones. This is hyaline cartilage.
- surrounded by articular capsule - surrounds joint enclosing the cavity - composed of
2 layers:
a. Fibrous Capsule - outer - dense connective tissue
- flexible - allows movement of joint but prevents dislocation - fibers become arranged in parallel bundles = ligaments
b. Synovial Membrane - inner - loose connective tissue with elastic fibers
- secretes synovial fluid which lubricates and provides nourishment to articular cartilage - similar to egg white in consistency - changes viscosity becoming less so with increased activity. Amount varies from joint to joint - but is only present in amount to just cover articular surfaces.
5. Accessory Ligaments
- may be extracapsular or intracapsular depending on whether they are inside or outside of the articular capsule.
- examples: extracapsular - fibular collateral ligament (in knee) intracapsular - cruciate ligaments (in knee)
6. Some joints (i.e. knee and TMJ) may have fibrocartilage “pads” between articular surfaces these are articular discs or menisci
7. Some joints (i.e. shoulder and hip) have a fibrocartilage rim to deepen the joint socket called a labrum.
Structural Classification: Bursae (4 details)
- sac-like structures similar to synovial joint cavity
- filled with fluid similar to synovial fluid
- found between bone and skin, muscle, tendon, or ligaments and help to reduce friction
- inflammation of bursa - bursitis
example: Housemaid’s knee or carpet layer’s knee
Articulating bones are basically held together by (3 factors) when speaking of joints other than cartilaginous or fibrous.
A. fit of the bones (e.g. ball and socket type)
B. joint ligaments and capsule
C. muscles around the joint
Types of Synovial Joints (6)
A. Gliding Joints (planar joints)(arthrodia) - permit back and forth, and side to side movement
only
- examples: carpals, tarsals
B. Hinge Joints (Ginglymus) - characterized by convex surface of bone fitting into concave surface of adjacent bone. Movement primarily in a single plane.
- examples: elbow, knee, ankle
C. Pivot Joints (trochoid) - primarily for rotation
- example: atlas and axis
D. Ellipsoidal or Condyloid - oval shaped condyle of bone fits into elliptical depression of adjacent bone(s).
- primarily for circumduction
- example: between radius and carpals in wrist
E. Saddle Joint (Sellaris) - mostly used to identify joint between trapezium and thumb metacarpal - similar to condyloid (ellipsoidal) - but permits freer movement - articular surfaces of both bones are saddle shaped.
- like a double hinge joint
F. Ball and Socket Joints (spheroid) - ball-like surface on one bone fitting into a cup-like surface on the other - permits movement in all 3 planes of motion.
- examples: shoulder and hip
The Knee Joint (What,8 details)
- largest joint of the body
actually could be considered as 3 joints in one - patella and femur
- medial and lateral tibiofemoral joints between respective condyles
*the patella femoral joint would be considered a Gliding Joint and the 2 tibiofemoral joints as hinge joints.
A. Articular Capsule - incomplete - made up mostly of muscle tendons surrounding the joint.
B. Patellar Retinacula (medial and lateral) portions of tendons fused from quadriceps femoris muscle - strengthen anterior portion of joint.
C. Patellar Ligament - central portion of above tendon extending from patella to tibial tuberosity.
D. Tibial Collateral Ligament - broad and flat ligament on medial side of joint. - same as Medial Collateral Ligament
E. Fibular Collateral Ligament - strong rounded cord-like ligament on lateral side of joint. - same as Lateral Collateral Ligament
F. Cruciate Ligaments - cross one another (thus the name)
1. Anterior Cruciate Ligament - extends posteriorly and laterally from intercondylar eminence of tibia (anterior) to lateral condyle of femur (posterior).
2. Posterior Cruciate Ligament - extends anteriorly and medially from intercondylar eminence (posterior) to medial condyle of femur (anterior).
*named according to where they attach to tibia.
G. Bursae - several in area of knee joint.
Prepatellar and Infrapatellar Subcutaneous Bursae
Suprapatellar and Infrapatellar Subtendinous Bursae
H. Menisci - fibrocartilage discs between tibial and femoral condyles.
1. Medial meniscus - shaped like a “C”
2. Lateral meniscus - shaped like a complete “O”
note: cruciate ligaments can be tested by moving lower leg forward or backward in flexed position
menisci are frequently injured - most commonly the medial - more difficult to diagnose - when knee is in flexed position - pain and tenderness just above plateau of tibia, plus limitation of full extension often indicates damage to menisci
collateral ligaments - holding the leg straight and stabilizing thigh - then trying to abduct or adduct lower leg is test for damage.
Hip Joint (Where,What,7 details)
- ball and socket joint formed by head of femur and acetabulum of coxal bone
A. articular capsule - very strong in hip joint
B. Iliofemoral ligament - arising from posterior superior portion of rim of acetabulum (ilium) and inserting on intertrochanteric line of the femur on anterior side. - one of the strongest in the body
- important for maintenance of standing
- forms a thickening in articular capsule stabilizing joint anteriorly
C. Ischiofemoral ligament - from body of ischium to posterior superior neck of femur - forms a thickening in articular capsule stabilizing joint posteriorly
D. Pubofemoral - from pubic bone to inferior surface of neck of femur. - forms a thickening in articular capsule giving inferior and posterior stabilization
E. Ligament of head of femur - from acetabular fossa to fovea of head of femur - only significance is that it carries blood vessels with it.
F. Acetabular Labrum - fibrocartilage rim attached to the margin of the acetabulum which serves to deepen socket of the joint
G. Transverse ligament of acetabulum - fills in the acetabular notch (acetabular notch = incomplete inferior portion of acetabulum and acetabular labrum)
Shoulder Joint (Where, 4 details)
- ball and socket joint between head of humerus and glenoid cavity.
A. Articular capsule - From Glenoid Labrum to Aanatomical neck. Loose, allowing considerable mobility
B. Glenoid Labrum - ring of fibrocartilage around ring of Glenoid fossa.
C. Glenohumeral Ligaments - 3 thickenings in capsule (superior, middle, and inferior) over anterior surface of joint - add little to joint stability
D. Joint has several bursae
Subdeltoid Bursae - deep to deltoid muscle over superior and lateral aspect of joint
Subscapularis Bursa - often an extension of synovial cavity, between subscapularis
tendon and middle glenohumeral ligament on anterior aspect of joint
Elbow Joint (4)
- could actually be considered as 2 joints:
- combination of a hinge (ulna) and a pivot (radius) joint
- trochlea of humerus and trochlear notch of ulna (hinge)
- capitulum of humerus and head of radius (pivot)
Ligaments (4)
A. Anterior and posterior ligaments - strengthen the articular capsule anteriorly and posteriorly
B. Annular ligament - extends from radial notch of the ulna, around the head of the radius and back to the ulna - can be easily damaged in children.
C. Lateral collateral ligament = Radial collateral ligament - triangular shape attached to lateral epicondyle of humerus and to the annular ligament
- often involved in irritation called “tennis elbow” (pitchers elbow)
D. Medial collateral ligament - actually has 3 parts:
1. anterior band - medial epicondyle to medial portion of coronoid process.
2. posterior band - medial epicondyle to medial portion of olecranon process.
3. transverse or oblique band - passes obliquely between the above 2 ligaments.
Temporomandibular Joint (Where, 3 parts)
- betweem temporal bone and condylar process of mandible
A. Articular Disc - composed mostly of fibrocartilage. Slide forward when jaw is opened
B. Lateral Ligament - attaches disc to temporal bone and mandible (Loose ligament causes Joint pathology = pain, clicking, locking, etc.)
C. Action of Joint = gliding motion between temporal bone and disc hinge motion between mandible and disc
Ankle Joint (4 parts)
A. Medial Ligament or Deltoid Ligament – triangular shaped ligament between the tibia, calcaneous, and navicular.
B. Anterior Talofibular Ligament – on lateral side between fibula and anterior talus
C. Posterior Talofibular Ligament – on lateral side between fibula and posterior talus
D. Calcaneofibular Ligament – on lateral side between fibula and calcaneous
Joint Disorders (9)
A. Rheumatism - very general term - dry painful state of the supporting structures of the body (bones, ligaments, joints, tendons, etc.)
B. Arthritis - inflammation of joints
C. Rheumatoid Arthritis - most common inflammatory form - involves loss of function along with pain and swelling. Primarily involves inflammation of synovial membrane. Membrane thickens and causes fluid to accumulate. Then abnormal tissue called pannus develops and adheres to surface of articular cartilage. This eventually causes erosion of cartilage.
D. Osteoid arthritis - common form - simply the deterioration of articular cartilage over time which becomes replaced by bone - does not involve inflammation. In advanced stages - C.T. replaces eroded cartilage and eventually ossifies causing fusion of the joint.
E. Tendonitis - inflammation of tendon sheaths
F. Gouty Arthritis
- Uric acid is a normal breakdown product of nucleic acid metabolism - excreted in urine
- If excess amounts are produced, or if normal excretion by the kidney of this compound is inhibited, its concentration in the blood will increase.
- Increased concentration in blood will cause precipitation in soft tissues of body.
- In a joint these crystals will cause irritation of the joints causing edema and extreme pain.
- Occurs primarily in males
- May sometimes be increased through the use of diuretics
G. Dislocation - also called luxation
- displacement of a bone from a joint
- often involves tearing of ligaments and/or tendons
H. Sprain - wrenching or twisting of joint without dislocation (“Subluxation”)
- may result in damage to associated blood vessels or muscles, or tendons, or ligaments, or nerves, or any combination of these.
I. Clubfoot - Talipes - common deformity of the foot where the bones of bones of the foot and ankle become abnormally arranged
- may be congenital or acquired - some kinds may possibly be due to abnormal positioning of the developing foot within the uterus.
