The objectives for this study would be to prospectively compare nerve blocks performed for postoperative analgesia performed using conventional (single bevel) needles to those performed using the fenestrated needle. Specifically, the investigators would compare metrics such as; time to perform the block, number of attempts, unintentional blood vessel puncture, and successful injection rates. Successful injection rates would be quantified by comparing the distribution of sensory loss after each injection. Those injections resulting in a loss of sensation over the skin surfaces innervated by nerves of the adductor canal would be judged to be "successful". An absence of sensory change in these surfaces would be judged as "unsuccessful".