First web space contracture and hand function.

We studied 125 normal volunteers to determine the normal first web space angle and to evaluate the influence of thumb-index finger web space contracture on hand function. One hundred ninety-five hands were measured and found to have a mean web space angle of 100 degrees. There was no significant difference in the mean angle in relation to sex or hand dominance. The mean angle was significantly smaller for persons 50 to 79 years of age than for the two younger age groups. Twenty-five normal volunteers (50 hands) took the Jebsen-Taylor test three times: first, with no restrictions; second, with splints simulating a 60-degree web space contracture; and third, with splints simulating a 30-degree contracture. More than half of the volunteers had abnormal small-object subtests. Other abnormal subtests included card turning, feeding, and stacking checkers. Grasping large light and heavy objects was less difficult because of compensatory techniques used by the volunteers.