Question

practice: joint classification
part 1: read each description and then complete the table. make sure to be as specific as possible when listing the names of the articulating bones and classifying the structural type of joint.

1. the metacarpophalangeal joint in your knuckle is considered freely moving and allows flexion, extension, abduction, and adduction.
2. the skull joint connects the two main sets of bones in the head that protect the brain and create the framework for the face with the upmost stability.
3. the pubic symphysis joint is connected only with cartilage and allows very slight movement – more so in pregnant women.
4. the ankle joint connects the lower leg bones with the talus and can only move in one direction, allowing for dorsiflexion and plantar flexion of the foot.
5. the costovertebral joint allows for a gliding motion in the ribs.
6. the sacroiliac joint in the pelvic girdle is fully moveable in childhood, allowing gliding movements. in adulthood it becomes more and more fibrous, allowing less and less movement.
7. the shoulder joint connects the scapula to the only bone in the upper arm. this joint has some of the most movement in the entire body, allowing flexion, extension, abduction, adduction, circumduction, and rotation.
8. the inferior tibiofibular joint connects the two bones of the lower leg on the distal end with ligaments only. this allows no movement.
9. the sternocostal joint is immovable, connecting the first rib with cartilage.
10. the distal radioulnar joint allows for supination and pronation in the forearm.

Answer:

To solve this, we analyze each joint based on articulating bones, functional type (synarthrosis, amphiarthrosis, diarthrosis), and structural type (fibrous, cartilaginous, synovial):

1. Metacarpophalangeal Joint

• Articulating Bones: Metacarpals, Phalanges
• Functional Type: Diarthrosis (freely moving)
• Structural Type: Synovial (Condylar)

2. Skull Joint (Sutures)

• Articulating Bones: Cranial bones (e.g., parietal, frontal, temporal, occipital)
• Functional Type: Synarthrosis (immovable)
• Structural Type: Fibrous

3. Pubic Symphysis

• Articulating Bones: Pubic bones (of pelvis)
• Functional Type: Amphiarthrosis (slight movement)
• Structural Type: Cartilaginous (Symphysis)

4. Ankle Joint (Talocrural)

• Articulating Bones: Tibia, Fibula, Talus
• Functional Type: Diarthrosis (freely moving)
• Structural Type: Synovial (Hinge)

5. Costovertebral Joint

• Articulating Bones: Ribs, Vertebrae (thoracic)
• Functional Type: Diarthrosis (gliding movement)
• Structural Type: Synovial (Plane)

6. Sacroiliac Joint

• Articulating Bones: Sacrum, Ilium
• Functional Type: Amphiarthrosis (childhood: diarthrosis; adulthood: amphiarthrosis)
• Structural Type: Fibrous (adulthood) / Synovial (childhood)

7. Shoulder Joint (Glenohumeral)

• Articulating Bones: Scapula (glenoid fossa), Humerus
• Functional Type: Diarthrosis (highly mobile)
• Structural Type: Synovial (Ball-and-Socket)

8. Inferior Tibiofibular Joint

• Articulating Bones: Tibia, Fibula (distal ends)
• Functional Type: Synarthrosis (immovable)
• Structural Type: Fibrous

9. Sternocostal Joint (1st Rib)

• Articulating Bones: Sternum, 1st Rib
• Functional Type: Synarthrosis (immovable)
• Structural Type: Cartilaginous (Synchondrosis)

10. Distal Radioulnar Joint

• Articulating Bones: Radius, Ulna (distal ends)
• Functional Type: Diarthrosis (allows supination/pronation)
• Structural Type: Synovial (Plane)

Final Table (Summarized)

Joint Description	Articulating Bones	Functional Type	Structural Type
2. Skull Joint (Sutures)	Cranial bones	Synarthrosis	Fibrous
3. Pubic Symphysis	Pubic bones	Amphiarthrosis	Cartilaginous (Symphysis)
4. Ankle Joint	Tibia, Fibula, Talus	Diarthrosis	Synovial (Hinge)
5. Costovertebral	Ribs, Thoracic Vertebrae	Diarthrosis	Synovial (Plane)
6. Sacroiliac	Sacrum, Ilium	Amphiarthrosis	Fibrous (adulthood)
7. Shoulder Joint	Scapula, Humerus	Diarthrosis	Synovial (Ball-and-Socket)
8. Inferior Tibiofibular	Tibia, Fibula (distal)	Synarthrosis	Fibrous
9. Sternocostal (1st Rib)	Sternum, 1st Rib	Synarthrosis	Cartilaginous (Synchondrosis)
10. Distal Radioulnar	Radius, Ulna (distal)	Diarthrosis	Synovial (Plane)

This table classifies each joint by its articulating bones, functional type (based on mobility), and structural type (based on tissue connecting bones).