Comparison of Bacteriostatic Saline to Buffered Lidocaine for Ultrasound Guided Hip Joint Injection Local Anesthesia

Local Anesthesia for Ultrasound Guided Hip Joint Injections: A Double-Blinded Randomized Controlled Trial of Bacteriostatic Saline Versus Buffered Lidocaine

The purpose of this study is to compare infiltration pain and anesthetic efficacy between lidocaine and Bacteriostatic saline (BS) for ultrasound (US) guided intraarticular hip injections.

Local anesthesia is commonly used to reduce pain during joint injections, particularly for deep joints like the hip. Lidocaine is the most commonly used local anesthetic in most medical practices. It is well known that lidocaine infiltration itself is painful. Many strategies have been studied to minimize pain associated with lidocaine administration, including buffering, warming, and slowing infiltration rate. BS is an alternative local anesthetic that has been shown to be less painful when injected into subcutaneous tissues compared with lidocaine. However, BS use has not been widely implemented for local anesthesia, and it has not been studied in the context of joint injections.

INCLUSION CRITERIA:

• age 18-75 years
• referred for US-guided intraarticular hip injections in the Mayo Clinic Sports Medicine Center, Physical Medicine & Rehabilitation Clinic, or Musculoskeletal Clinic

EXCLUSION CRITERIA:

• chronic opioid use
• opioid use on day of procedure
• history of fibromyalgia or other diffuse chronic pain syndrome
• pain behavior during the clinical encounter as judged by the injectionist
• anesthetic administration time outside the designated 5-15 second time frame