Equine Anatomical Terminology Flashcards
What is the definition of the joint?
- Location at which two or more bones make contact
- constructed to allow movement and provide mechanical support
- sterile: especially important because when they are exposed to the outside world and infection can start in the joint and do a lot of damage very quickly
How are joints classified through structure?
how bones are structurally classified
1. fibrous joint
2. cartilaginous joint
3. synovial joint (most are synovial)
Describe fibrous joints
- Joined by dense connective tissue (CT) composed primarily of collagen
- immovable
- ossify with age: cartilage ossifies with age
What are examples of fibrous joints?
sutures - between the bones of skulls
syndesmosis - between long bones
- ulna and radius
- fibula and tibia
- metacarpals/metatarsals
Describe cartilaginous joints
- joined by cartilage
- symphysis: joined by fibrocartilage
What are examples of cartilaginous joints?
- pelvic symphysis: ossifies with age
- intervertebral discs: do not normally ossify with age
What is synchondrosis?
joined by hyaline cartilage
What are examples of synchrondrosis?
growth plate (physis) and rib to costal cartilage
Describe a synovial joint
- includes hyaline cartilage
- covers bone epiphysis
- smooth and resistance to wear
- moveable
- only type with a joint cavity
What are the parts of the bone?
diaphysis (long part of the bone)
metaphysis (the part where the bone flares out)
the growth plate (physis)
epiphysis (end of the bone covered by articular cartilage)
What supports the joint cavity?
ligaments and tendons surround the joint cavity to provide even more support and holding everything in place. When these wear it causes osteoarthritis causing pain in the joint
What is the synovial joint capsule?
- outer layer = fibrous, dense, anastomoses with periosteum
- inner layer = synovial membrane
- vascular, comprised of loose CT
- covers entire joint except area covered by hyaline cartilage
- secrete synovial fluid = fills joint cavity, thick, yellow-tinged, high viscosity
What do ligaments do?
help reinforce capsule and prevent excessive movement within joint
periarticular (close to a joint) and intra-articular (ligaments inside the joint itself ex: stifle and knee)
Where does synovial fluid come out of?
the synovial membrane
What is the functional classifications of joints
degree of mobility:
1. synarthrosis: permits little or no mobility and most are fibrous joints (skull)
2. amphiarthrosis: permits slight mobility and most are cartilaginous joints (vertebrae)
3. diarthrosis: permits variety of movements and all are synovial joints (shoulder)
What are the other developments of synovial joints?
flexion: bending limb at joint
extensions: straightening limb at joint
abductions: movement away from midline
adductions: movement toward midline
rotation: circular movement around fixed point and ball and socket
What are the joint biochemical classifications?
- simple joint: 2 articulation surfaces (joints and if there is added things in the joints)
ex: shoulder and hip
- compound joints: 3+ articulation surfaces (more than two bones included)
ex: radiocarpal
- complex joint: 2+ articulation surfaces (doesn’t matter how many articulation surfaces, needs a meniscus or something else added to be complex)
ex: articular disc or meniscus and stifle
Describe a ligament
attach bone to bone
stabilize joints
support structures
comprised of strong, inelastic fibrous tissue
Describe joint ligaments
periarticular: collateral ligaments, aid in controlling range of motion, typically flexion and extension
intra-articular: synovial membrane reflected over them
Describe desmitis
inflammation of a ligament, take time to heal due to relatively poor blood supply
ex: suspensory desmitis, curb
Describe tendon
attach muscle to bone
comprised of string, elastic fibrous tissue:
capacity to store energy when stretch, elastic recoil contributed to locomotion
Describe tendon classifications
flexors and extendors
What is tendonitis
inflammation of a tendon, take time to heal due to lack of good blood supply
Describe a tendon sheath
Protects tendons as it passes over a joint
contains ‘synovial’ fluid as a lubricant: sterile
ex: Digital tendon sheath around DDFT and SDFT
