ACSM Certified Personal Trainer (CPT) — Question 23

Which of the following is characterized as a plane (uniaxial) joint?

Answer options

• A. Coxal (hip)
• B. Atlantooccipital
• C. Radiocarpal (wrist)
• D. Sacroiliac

Correct answer: D

Explanation

The sacroiliac joint is classified as a plane joint because it allows for limited gliding movements between the sacrum and the ilium. In contrast, the coxal joint (hip) is a ball-and-socket joint, the atlantooccipital joint allows nodding movements, and the radiocarpal joint is a condyloid joint allowing for more movement than a uniaxial joint.