Clinical evaluation of flexor tendon function in the small finger.

Patients frequently present to the emergency department with hand injuries. Standard examination includes testing each digit for flexor function. The flexor digitorum superficialis (FDS) to the small finger has been shown to have variable anatomy and clinical examination. We prospectively examined 100 subjects (200 hands) for small finger FDS function by standard and modified testing. We found that 70 small flexors (35%) showed absent FDS by standard testing, whereas only eight fingers (4%) had absent FDS by modified testing. FDS function to the small finger is frequently unilateral. We conclude that modified testing is the only way to accurately test for small finger FDS function and that the use of this simple clinical examination may prevent unnecessary referral to a hand surgeon.