Hypotonia may present with which joint position at the elbows and knees?

Hypotonia may present with which joint position at the elbows and knees?

• A. Flexion
• B. Hyperextension
• C. Pronation
• D. Varus

Answer: (B)

Low muscle tone reduces the limb’s ability to actively stabilize joints, so the joints often settle in extended positions. At the elbows and knees, this means a tendency toward hyperextension because there isn’t enough tone to maintain a flexed or neutral posture, and the joints can collapse into extension under gravity. This pattern—elbows and knees resting in a straight or slightly hyperextended position—is a common sign of hypotonia. Flexion would imply a persistent bent position that relies on stronger flexor tone, which isn’t typical of hypotonia. Pronation refers to forearm rotation rather than a sustained extended posture of the elbow, and varus describes inward angulation of the limb, which isn’t the hallmark presentation of hypotonia at these joints.

Low muscle tone reduces the limb’s ability to actively stabilize joints, so the joints often settle in extended positions. At the elbows and knees, this means a tendency toward hyperextension because there isn’t enough tone to maintain a flexed or neutral posture, and the joints can collapse into extension under gravity. This pattern—elbows and knees resting in a straight or slightly hyperextended position—is a common sign of hypotonia.

Flexion would imply a persistent bent position that relies on stronger flexor tone, which isn’t typical of hypotonia. Pronation refers to forearm rotation rather than a sustained extended posture of the elbow, and varus describes inward angulation of the limb, which isn’t the hallmark presentation of hypotonia at these joints.