Functional Absence of Flexor Digitorum Superficialis to the Little Finger and Absence of Palmaris Longus – Is There A Link?

We examined 150 men and 150 women aged 18–40 years to assess flexor digitorum superficialis function to the little finger and the incidence of palmaris longus absence. All patients had flexor digitorum superficialis function to the little finger assessed by standard and modified tests. The presence or absence of palmaris longus was assessed by clinical inspection. Following modified testing, ten subjects (14 hands) displayed absolute superficialis deficiency to the little finger. Forty-nine subjects had unilateral absence of palmaris longus (16%). This tendon was absent bilaterally in 26 subjects (9%). On combining the clinical findings, one subject had unilateral absence of flexor digitorum superficialis function to the little finger with contralateral absence of palmaris longus, and one subject had bilateral absence of flexor digitorium superficialis function with unilateral absence of palmaris longus. We conclude that there is no link between an absent little finger flexor digitorium superficialis and an absent palmaris longus.