Direct intracompartmental pressure (ICP) measurement in children is an important investigation, the use of which may be inhibited by the invasive nature of the procedure and the large 18-gauge (G) needles that have hitherto been recommended. These large needles contribute to patient, parental, and physician anxiety. This study compares ICP measurements using needles of different lengths and port configuration, ranging from 18 to 25 G, against the "gold standard" 18 G, long, double-ported needle. All except the 18 G long, single-ported needle had limits of agreement within 3 mm Hg of the gold-standard needle. The results indicate that needle manometry can confidently be performed using small needles, and that the addition of a side-port is unnecessary in needles of small volume.