Q_Upper limb=q31 - miracoli

[ArchivalUser]

On the advice of a lawyer, a 27-year-old employee visited her personal physician because she found she could no longer flex her thumb and was unable to deal cards. Examination revealed weakness at the interphalangeal joint of the thumb as well as difficulty in bending the tips of the index and middle fingers. She could make a fist but had some difficulty in pinching with the thumb and index finger. There was some forearm pain but no tingling or numbness. These symptoms indicate damage to which of the following nerves?
A. Posterior interosseus branch of the radial nerve
B. Palmar branch of the ulnar nerve
C. Recurrent branch of the median nerve
D. Anterior interosseus branch of the median nerve
E. Digital branches of the ulnar nerve

[ArchivalUser]

C. ty

[ArchivalUser]

Agree with "C." Thank you.

[ArchivalUser]

Which muscles become weak in this pt?

[ArchivalUser]

D no pulp pinch

[ArchivalUser]

In this pt, thenar muscles normal or weak? Which other muscles are weak?

[ArchivalUser]

D.
The Flexor pollicis longus n Flexor digitorum profundus - Anterior interosseous br, of Median nv.
The thenar muscles xcept the adductor pollicis is supplied by recurrent branch.
Thenar wasting not possible.
Usually an upper forearm compressive pathology.

[ArchivalUser]

Pronator quadratus is also weak.....
Anterior interosseous provides supply to deep muscular layer of the forearm..

[ArchivalUser]

D is correct.
@Byzantine thank you for explanation
Thank you everybody for participating!

ANTERIOR INTEROSSEOUS NERVE[AIN]
- arises from the median nerve in the upper forearm and descends on the interosseous membrane between the FDPand the FPL and passes behind the pronator quadratus
-it innervates flexor digitorum profundus, the flexor pollicis longus and the pronator quadratus. So it mediates flexion of both the thumb and distal interphalangeal joints of the index and middle fingers. Lesion of AIN causes an abnormal "pinch attitude" [triangular looking structure] when the patient is asked to make an "OK" sign with their index finger and thumb.
http://www.orthopaedicsone.com/download/...2845190000
http://www.orthopaedicsone.com/download/...2845190000
-There is weakness with thumb flexion as a result of flexor pollicis longus paralysis. But there is still some flexor function, because the flexor pollicis brevis muscle would still be intact. The pronator teres is able to compensate the function of the paralysed pronator quadratus.
-AIN has NO sensory distribution
RECURRENT (motor) BRANCH of the median nerve
-arises from median nerve in the palm after passing the carpal tunnel
-it innervates the 3 thenar muscles: the opponens pollicis, flexor pollicis brevis, and abductor pollicis brevis muscles). The adductor pollicis is a thumb muscle but not part of the thenar compartment and is innervated by the DEEP BRANCH OF THE ULNAR NERVE