Pain produced by the tourniquet is a common source of complaint for patients undergoing carpal tunnel decompression. Practice varies as to tourniquet position. There is little evidence to suggest benefit of one position over another. Our aim was to compare the experience of both the patient and the surgeon with the tourniquet placed either on the arm or the forearm.

Ethical approval was granted. Following power calculation and a significance level set at 0.05, 100 patients undergoing open carpal tunnel decompression under local anaesthetic were randomised to arm or forearm group. Visual Analogue Scores (VAS) (0–100) for pain, blood pressure and heart rate were taken at 2 minute intervals. The operating surgeon provided a VAS for bloodless field achieved and obstruction caused by the tourniquet.

The demographics of the groups was similar. There were no statistically significant differences in any measure between the groups.

Average tourniquet times were 8.8 minutes (forearm) and 8.2 minutes (arm). The average VAS score for forearm and arm was 13 and 11 respectively for bloodless field, 9 and 2 for obstruction. Average overall VAS for pain was 27 in each group, however interval VAS scores for pain were higher in the arm group. The average change Mean Arterial Pressure was −5 mmHg (forearm) −2 mmHg (arm) pulse rate was −1 bpm (forearm) and −2 bpm (arm).

Tourniquet placement on the arm does not result in significant difference in patient pain, physiological response or length of operation. Surgeons reported less obstruction and better bloodless fields with an arm tourniquet, however there was a trend for forearm tourniquet to result in less pain for the patient.