Objective. To determine whether leaving an intrathecal catheter in place in the postoperative period prevents postdural puncture headache (PDPH). Methods. Lumbar puncture was performed with an 18-gauge Tuohy needle. 0.5% bupivacaine spinal anesthesia was given through a 20-gauge catheter in 87 patients having orthopedic surgery. Postoperatively, patients were allocated randomly to have the catheter immediately withdrawn (group 1, N = 47) or kept in place for 12 to 24 hours (group 2, N = 40). Patients were questioned by a blinded observer, about PDPH twice a day on postoperative days 1, 2, 3, and 8. Results. The incidence of PDPH was 9.2%, and this was comparable in the two groups (5 patients in group 1 and 3 patients in group 2). Conclusion. Leaving the intrathecal catheter in place in the postoperative period for 12 to 24 hours does not prevent PDPH.