The nurse is caring for a patient who has had an arthrocentesis. The nurse has completed discharge instructions. Which statement by the patient indicates the need for further instruction?

Correct Answer: A

Rationale: Arthrocentesis, removing fluid from a joint, aims to relieve pressure and improve mobility. Saying the knee mustn't move for 1-2 weeks suggests misunderstanding, as gentle movement is typically encouraged soon after to prevent stiffness, with rest limited to a day or two unless specified otherwise. Steroids reducing inflammation is accurate, as they're often injected post-procedure. Expecting some pain aligns with recovery, as does wearing a bandage for 2-3 days for support. The prolonged immobility statement requires correction, as it contradicts the goal of restoring function, risking complications like adhesions further teaching ensures the patient balances rest and activity correctly.

Correct Answer: C

Rationale: Fixators are muscles that stabilize the origin of a prime mover, allowing it to move more effectively by preventing unwanted movement at the point of attachment. This stabilization ensures that the force generated by the prime mover is directed toward the intended action, such as lifting or rotating a limb. For example, in shoulder abduction, fixator muscles stabilize the scapula so the deltoid can efficiently lift the arm. Superficial describes muscle location, not function. Synergists assist the prime mover by reducing unnecessary movement or enhancing its action, but they do not specifically stabilize the origin. Aponeurosis is a structural term for a tendon-like sheet, not a muscle type or function. The role of stabilizing the origin is a distinct characteristic of fixators, making it the correct choice here, as it directly supports the prime mover's efficiency in movement.

Correct Answer: A

Rationale: The anal triangle is the posterior region of the pelvic floor, containing the anus and bounded by the coccyx and ischial tuberosities. It's distinct from the anterior urogenital triangle and is key in understanding perineal anatomy, especially in procedures like episiotomies. Fixators are muscles, not regions. Origin and insertion are muscle attachment points, not pelvic areas. The anal triangle precisely fits the description, making it the correct answer, as it identifies the specific anatomical zone housing the anus, critical for both structural and clinical contexts in the pelvic floor.

Correct Answer: A

Rationale: Mastication (chewing) involves the masseter, temporalis, and medial/lateral pterygoid muscles, which elevate, retract, and laterally move the mandible. The masseter is the strongest, closing the jaw; temporalis assists in elevation and retraction; pterygoids enable grinding. Genioglossus and related tongue muscles move the tongue, not the jaw. Omohyoid and neck muscles affect the hyoid, not mastication. Rectus abdominis is an abdominal muscle, unrelated. The masseter-temporalis-pterygoid group is the correct answer, as it directly powers jaw movement during chewing, critical for breaking down food, unlike the other muscle groups focused on different functions.

Correct Answer: C

Rationale: The biceps brachii has two origins (long and short heads) on the scapula and is located in the upper arm, inserting on the radius to flex the elbow. It's not in the forearm (that's brachioradialis), nor deep to the brachialis (it's superficial). It doesn't have two insertions or reside in the leg. Two origins and upper arm location define the biceps brachii, making it the correct answer, reflecting its anatomical structure and function as a prominent arm flexor.