Hypothesis: When comparing superficial infiltration of local anesthetic to superficial and deep infiltration of local anesthetic in the setting of carpal tunnel release, the null hypothesis is that there will be no significant difference between the two techniques.

Background and study rationale: Carpal tunnel syndrome is a very common clinical problem with significant patient burden that can be reliably treated with surgical carpal tunnel release. To minimize operating room time burdens and to improve patient recovery time, this procedure is generally performed with the patient wide awake using local anesthetic. While the majority of patients are able to tolerate this type of procedure, there is always a possibility of some discomfort or pain experienced during the procedure. The investigators would like to compare two local anesthetic infiltration techniques to determine which is best to provide the least amount of pain or discomfort during a carpal tunnel release. The two methods are subcutaneous infiltration alone (superficial) and subcutaneous infiltration with infiltration into the carpal tunnel (deep).

Research Design: This study design is a prospective randomized control trial.

Methodology: Patients will be recruited and randomized on the morning of their surgery to undergo either superficial or superficial and deep local anesthetic infiltration using 10cc of 1% lidocaine with epinephrine buffered with 8.4% sodium bicarbonate. They will be blinded as to which group they are in.

Participants will complete the Boston Carpal Tunnel Questionnaire as a baseline for comparison as well as a brief questionnaire on demographics. After the procedure, participants will complete a short questionnaire about any pain experienced during the administration of the local anesthetic and during the procedure. Presence and intensity of pain during the procedure are the primary outcome of this study.

Secondary outcomes include pain rating at 2, 8, and 24 hours post-procedure and a follow up Boston Carpal Tunnel Questionnaire score at 3 months. The surgeon will also make note whether there is any visible evidence of damage to the median nerve from deep infiltration at the time of surgery.

Statistical Analysis: The two groups (superficial vs. deep) will be compared directly for each of the outcomes listed in the methodology.

Inclusion Criteria:

• > 18 years of age
• Undergoing carpal tunnel release

Exclusion Criteria:

• Patients undergoing repeat carpal tunnel release
• Patients undergoing simultaneous procedures for other hand/wrist pathology at the time of carpal tunnel release (i.e. trigger finger release, Dupuytren's, etc.)
• Patients with a history of Rheumatoid Arthritis or a history or previous trauma or surgery to the local area (i.e. distal radius fracture)
• Patients who lack the capacity to provide informed consent or understand the nature of the project