Articulations Part 2 Study Guide Flashcards
What two types of movement are allowed by the TMJ?
- hinge; depression and elevation of the mandible
- gliding; side-side/lateral excursion when mouth is open
What two bones articulate in the TMJ?
- temporal bone
- mandible bone
In which direction(s) must the mandible be moved to relocate it after dislocation?
-inferiorly and posteriorly
Why is the shoulder somewhat easy to dislocate? Name two reasons.
- high mobility without much stability
- glenoid cavity provides poor support when the arm is rotated and abducted
In a dislocation, which direction is the humeral head most likely to move?
anteriorly and inferiorly
Name the 4 muscles of the rotator cuff.
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
What structures attempt to reinforce or make the shoulder more stable? Which of these contributes most to joint stability?
- glenoid labrum; fibrocartilage rim around glenoid cavity to increase its depth
- reinforcing ligaments
- coracohumeral ligament; helps support weight on the upper limb
- 3 glenohumeral ligaments; slightly strengthen the anterior capsule
- reinforcing muscle tendons (CONTRIBUTE MOST TO STABILITY)
- tendon of the long head of the biceps brachii is a super stabilizer that travels through the intertubercular sulcus and secures the head of the humerus to the glenoid cavity
What bones articulate in the elbow joint? What movements are allowed?
- radius and ulna articulate with humerus
- allows for flexion and extension only
Name the ligament that encircles the head of the radius.
- annular ligament
Name the ligaments that restrict side to side movement at the elbow.
- ulnar collateral ligament
- radial collateral ligament
What bones articulate in the hip joint?
- Head of the femur articulates with the deep, cup-shaped acetabulum
What makes the hip joint more stable than the shoulder joint? What structure additionally reinforces the joint?
- Thick articular capsule
- Acetabular labrum; rim of fibrocartilage that further enhances depth of the socket (that is much deeper than the the shoulder joint)
List 4 reinforcing ligaments of the hip joint. Make note of which bones are connected by each listed ligament.
- Iliofemoral ligament
- Pubofemoral ligament
- Ischiofemoral ligament
- Ligamentum teres (runs through head of femur to lower lip of acetabulum)
Name the 3 separate joints within the knee joint. What motions are allowed by the tibiofemoral joint?
- Femoropatellar joint
- Lateral joint
- Medial joint
Motions of the tibiofemoral joint = flexion, extension, and some rotation
On the inferior side of the patella, the quadriceps tendon becomes the —–, —— , and ——- .
- medial patellar retinacula,
- lateral patellar retinacula
- patellar ligament
List the 4 capsular and extracapsular ligaments of the knee and their functions in stabilizing the knee.
- Fibular collateral ligament; prevent rotation of an extended knee
- Tibial collateral ligament; prevents rotation of an extended knee
- Oblique popliteal ligament; stabilizes the posterior knee joint, part of the tendon of the semimembranosus]
- Arcuate popliteal ligament; reinforces the posterior joint capsule
List the 2 intracapsular ligaments of the knee and their functions in stabilizing the knee.
- Anterior cruciate ligament acl; attaches to the anterior tibia, prevents anterior sliding of the tibia and knee hyperextension
- Posterior cruciate ligament pcl, attaches to posterior tibia; prevents posterior sliding of the tibia and anterior sliding of the femur
What’s the unhappy triad? How is it most likely to occur?
- Unhappy triad; tears in the tibial collateral ligament, the medial meniscus, and the anterior cruciate ligament
- Most likely to occur with a lateral blow to the knee
What’s a meniscectomy? Why should one be performed?
Removal of the meniscus between femur and tibia if its badly torn and threads of it are getting caught in joint and restricting joint movement
Define a sprain. What structures are damaged?
Stretching or tearing of the reinforcing ligaments, often the ankle and knee
What are the 3 chronic forms of arthritis? Which of these 3 forms is the most common in the US?
- Osteoarthritis MOST COMMON
- Rheumatoid arthritis
- Gouty arthritis
Define bursitis, tendonitis, and arthritis.
- Bursitis; inflammation of the bursa, typically caused by a blow or friction
- Tendonitis; inflammation of the tendon sheaths, typically caused from overuse
- Arthritis; inflammatory or degenerative diseases that damage joints. Over 100 diff types, very common in US, symptoms are pain, stiffness, swelling of joints, acute arthritis may be caused by bacteria and treated with antibiotics. Chronic forms = osteoarthritis, rheumatoid arthritis, and gouty arthritis
What happens in a dislocation? In a subluxation?
Bones are moved out of alignment
Subluxation; a partial dislocation
What causes osteoarthritis? What anatomical structure is damaged?
- Often occurs in response to uneven forces
- May reflect excessive release of the enzymes that break down articular cartilage - osteophytes (bone spurs) may form from thickened bone ends
