Review

Femoral nerve blocks for acute postoperative pain after knee replacement surgery.

Cochrane Db Syst Rev. 2014 May 13; 2014 (5): CD009941CD009941.

Femoral nerve block is better than PCA alone after total knee replacement, although comparison to local infiltration is unclear.
pearl
Randomized Controlled Trial

Prospective randomized clinical trial comparing patient-controlled intravenous analgesia with patient-controlled epidural analgesia after lumbar spinal fusion.

Spine. 2003 Apr 15;28(8):739-43.
Randomized Controlled Trial

Analgesic effect of ultrasound-guided transversus abdominis plane block after total abdominal hysterectomy: a randomized, double-blind, placebo-controlled trial.

Acta Obstet Gynecol Scand. 2015 Mar 1;94(3):274-8.