De Quervain's Tenosynovitis involves tendinopathy of which tendons at the first dorsal compartment?

De Quervain's Tenosynovitis involves tendinopathy of which tendons at the first dorsal compartment?

• A. Flexor pollicis longus
• B. Abductor pollicis longus and Extensor pollicis brevis
• C. Extensor pollicis longus
• D. Extensor carpi radialis brevis

Answer: (B)

De Quervain's tenosynovitis is a stenosing problem of the first dorsal wrist compartment, where the abductor pollicis longus and extensor pollicis brevis tendons glide. When the sheath around these tendons becomes inflamed or thickened, thumb movements—especially abduction and extension—tendon pain and tenderness at the radial-dorsal wrist. The other tendons listed are not in this compartment: the flexor pollicis longus is a palmar-side flexor, the extensor pollicis longus runs in a different (third) dorsal compartment, and the extensor carpi radialis brevis is in the second dorsal compartment. So the tendinopathy involves the two tendons contained in the first dorsal compartment: abductor pollicis longus and extensor pollicis brevis.

De Quervain's tenosynovitis is a stenosing problem of the first dorsal wrist compartment, where the abductor pollicis longus and extensor pollicis brevis tendons glide. When the sheath around these tendons becomes inflamed or thickened, thumb movements—especially abduction and extension—tendon pain and tenderness at the radial-dorsal wrist. The other tendons listed are not in this compartment: the flexor pollicis longus is a palmar-side flexor, the extensor pollicis longus runs in a different (third) dorsal compartment, and the extensor carpi radialis brevis is in the second dorsal compartment. So the tendinopathy involves the two tendons contained in the first dorsal compartment: abductor pollicis longus and extensor pollicis brevis.