Long m/s located at the deep layer with flexor digitorum profundus

Flexor Pollicis longus

→ Long m/s located at the deep layer with flexor digitorum profundus & pronator quadratus in the anterior compartment of the forearm.

Anterior Interosseous Syndrome

→ Isolated palsy of flexor pollicus longus, the index and long fingers of the flexor digitorum profundus, and the pronator quadratus muscles of the forearm.

Pinch Grip Test/ Froment’s Sign

→ Rather than making the “OK” sign, the patient will clap the sheet between the index finger and an extended thumb.