Most neurosurgeons use a frontal burr hole in stereotactic thalamotomy for movement disorders. However, the reports on this operation show a variation in trajectory with reference to the angles to the intercommissural line and the midsagittal plane. We studied the effect of the trajectory angles on operative results in 22 patients who underwent stereotactic thalamotomy for tremor control. The angle varied between 28 and 71 degrees (mean 44 +/- 10) in the sagittal plane, and between 0 and 25 (mean 11 +/- 7) in the coronal plane. There was linear correlation between the angles and the distances of a burr hole from the coronal suture and the midline. However, the angles did not show any correlation with the number of target corrections required, the size of the lesions made, tremor control and the incidence of complications. These findings indicate that the trajectory angle does not play an important role in stereotactic thalamotomy.