Which physical finding is commonly associated with Duchenne muscular dystrophy?

Which physical finding is commonly associated with Duchenne muscular dystrophy?

• A. Decreased calf size.
• B. Enlarged calf muscles (pseudohypertrophy).
• C. Increased hair growth on legs.
• D. Heightened reflexes.

Answer: (B)

In Duchenne muscular dystrophy, muscle fibers gradually degenerate and are replaced by fat and connective tissue. This causes the calves to look enlarged even though the muscles are weak—the classic pseudohypertrophy. The calf enlargement reflects fat and fibrous tissue accumulation, not true muscle growth, and is a well-known physical finding in DMD. This condition also features early-onset proximal muscle weakness and a positive Gowers maneuver, with progression leading to loss of ambulation. The other options don’t fit because decreased calf size would indicate muscle wasting rather than replacement by fat, increased leg hair growth isn’t related to this muscle disease, and reflexes are not typically heightened in DMD (they may be normal or reduced as weakness progresses).

In Duchenne muscular dystrophy, muscle fibers gradually degenerate and are replaced by fat and connective tissue. This causes the calves to look enlarged even though the muscles are weak—the classic pseudohypertrophy. The calf enlargement reflects fat and fibrous tissue accumulation, not true muscle growth, and is a well-known physical finding in DMD. This condition also features early-onset proximal muscle weakness and a positive Gowers maneuver, with progression leading to loss of ambulation.

The other options don’t fit because decreased calf size would indicate muscle wasting rather than replacement by fat, increased leg hair growth isn’t related to this muscle disease, and reflexes are not typically heightened in DMD (they may be normal or reduced as weakness progresses).