Does Ethyl Chloride Spray Work?

Does "Freeze Spray" Work? Evaluating the Efficacy of Ethyl Chloride Usage Prior to Orthopaedic Injections

A procedure frequently performed by orthopaedic providers is the administration of corticosteroid injections for the management of various soft tissues and joint-related conditions, such as osteoarthritis, tendinitis, carpal tunnel syndrome, trigger finger, and de Quervain's tenosynovitis. While these injections have demonstrated effectiveness in alleviating symptoms, the discomfort associated with the procedure can be a source of anxiety and apprehension for patients. This discomfort arises from the sensation of the needle entering the affected area and the burning sensation induced by the corticosteroid solution.

Study Overview

• Status: Recruiting
• Conditions: Injection Fear; Injection Complication; Injection Pain Prevention
• Intervention / Treatment: Other: Ethyl Chloride; Other: Cold Saline Spray

Detailed Description

A procedure frequently performed by orthopaedic providers is the administration of corticosteroid injections for the management of various soft tissues and joint-related conditions, such as osteoarthritis, tendinitis, carpal tunnel syndrome, trigger finger, and de Quervain's tenosynovitis. While these injections have demonstrated effectiveness in alleviating symptoms, the discomfort associated with the procedure can be a source of anxiety and apprehension for patients. This discomfort arises from the sensation of the needle entering the affected area and the burning sensation induced by the corticosteroid solution.

In response to this concern, orthopaedic providers have turned to freeze sprays (Ethyl chloride), which are topical anesthetics that rapidly cool the skin and underlying tissues. By numbing the injection site superficially, freeze sprays offer the potential to mitigate patient discomfort during corticosteroid injections, thus improving the overall patient experience and potentially enhancing treatment compliance.

However, despite the popularity of freeze spray usage in orthopaedics, many orthopaedic providers have concerns about its efficacy when it comes to providing pain relief. There still needs to be comprehensive scientific evidence evaluating its efficacy and safety. A previous study evaluated the efficacy of freeze spray in hand surgery in a randomized study of 150 subjects without standardized outcomes measures. These investigators showed no difference between those receiving freeze spray vs no spray in pain or anxiety; another study of vapocoolant spray in IV start sites in the emergency department similarly showed no difference in pain or anxiety. Based on the literature, there is no definitive standard of care to use freeze spray with injections and this is the gap in knowledge we wish to answer with a rigorous, placebo-controlled study. This study will differ from the previous similar study in that the investigators will recruit double the number of patients and use standardized commonly accepted questionnaires. The use of a questionnaire based on standardized metrics will provide a more comprehensive assessment of patient perceptions and satisfaction with the use of freeze spray. Through a rigorous research approach, the investigators aim to provide valuable insights into the impact of freeze spray on patient comfort, injection success rates, and any potential complications associated with its use.

This study will contribute to the ongoing efforts of hand surgeons to refine their techniques, minimize patient discomfort, and optimize the delivery of corticosteroid injections. Ultimately, the investigators' findings may have significant implications for the broader field of musculoskeletal medicine, offering evidence-based guidance to improve the patient experience and outcomes in orthopaedic surgery.

• Study Type: Interventional
• Enrollment (Estimated): 300
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jennifer M Wolf, MD, PhD; Phone Number: 773-834-3531; Email: jwolf@bsd.uchicago.edu
• Study Contact Backup: Name: Jordan Swindle, MD; Email: jordan.swindle@uchicagomedicine.org

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60637
      • Recruiting
      • University of Chicago
      • Contact: Jennifer M Wolf, MD; Phone Number: 773-834-3531; Email: jmwolf@uchicagomedicine.org
      • Contact: Michael K Koch, Bachelor's; Phone Number: 7738340822; Email: mkoch@bsd.uchicago.edu
      • Principal Investigator: Jennifer M Wolf, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 18 years and older
• Receiving a corticosteroid injection in an upper or lower extremity (to include soft tissue and joint injections) for the first time

Exclusion Criteria:

• Patients with previous injection experiences

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Freeze spray group; Ethyl Chloride Usage Prior to Orthopaedic Injections	Other: Ethyl Chloride; Topical anesthetic that rapidly cools the skin and underlying tissues
Placebo Comparator: Placebo application of cold saline spray; Saline spray before injection	Other: Cold Saline Spray; placebo application of cold saline spray
No Intervention: No spray prior to injection; No intervention before injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To determine if freeze spray usage before corticosteroid injections significantly reduces patient discomfort during the procedure as measured by pain scores before injection	Using the visual analog pain scale (0 no pain - 10 worst possible pain) to ask patients their pain rating and if freeze spray usage before corticosteroid injections significantly reduces patient discomfort during the procedure.	10 minutes before subject receives injection
To determine if freeze spray usage before corticosteroid injections significantly reduces patient discomfort during the procedure as measured by pain scores after injeciton	Using the visual analog pain scale (0 no pain - 10 worst possible pain) to ask patients their pain rating and if freeze spray usage before corticosteroid injections significantly reduces patient discomfort during the procedure.	10 minutes after subject receives injection
To assess patient perception of freeze spray efficacy in decreasing anxiety regarding injections.	Using the treatment satisfaction questionnaire for medication-II to ask patients their anxiety and if freeze spray usage before corticosteroid injections significantly reduces patient anxiety during the procedure.	10 minutes after subject receives injection
To assess their current overall status compared to their pre-injection baseline	Using the single assessment numeric evaluation (0% furthest from normal and 100% normal) to ask patients their current status	10 minutes after subject receives injection

Collaborators and Investigators

• Sponsor: University of Chicago

Publications and helpful links

General Publications

• Franko OI, Stern PJ. Use and Effectiveness of Ethyl Chloride for Hand Injections. J Hand Surg Am. 2017 Mar;42(3):175-181.e1. doi: 10.1016/j.jhsa.2016.12.013.
• Randall DJ, Zhang Y, Li H, Hubbard JC, Kazmers NH. Establishing the Minimal Clinically Important Difference and Substantial Clinical Benefit for the Pain Visual Analog Scale in a Postoperative Hand Surgery Population. J Hand Surg Am. 2022 Jul;47(7):645-653. doi: 10.1016/j.jhsa.2022.03.009. Epub 2022 May 27.
• Edwards C, Noah C. A Randomized, Double-Blind Trial to Determine if Vapocoolant in the Adult Population Improves Patient Perception of Pain With Peripheral Intravascular Access. Adv Emerg Nurs J. 2017 Oct/Dec;39(4):288-294. doi: 10.1097/TME.0000000000000165.
• Morote Robles J, Lorente JA, Reig C, Lopez Pacios MA, de Torres JA, Soler Rosello A. [The clinical and prognostic value of inversion of the PSA/PAP ratio in prostatic cancer]. Actas Urol Esp. 1994 May;18(5):559-61. Spanish.

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2025
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: October 17, 2024
• First Submitted That Met QC Criteria: October 18, 2024
• First Posted (Actual): October 22, 2024

Study Record Updates

• Last Update Posted (Estimated): October 16, 2025
• Last Update Submitted That Met QC Criteria: October 14, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Keywords: Injection; corticosteroid injections; Freeze spray; Ethyl chloride; Orthopeadics
• Additional Relevant MeSH Terms: Iatrophobia; Organic Chemicals; Hydrocarbons; Hydrocarbons, Halogenated; Hydrocarbons, Chlorinated; Ethyl Chloride
• Other Study ID Numbers: IRB23-2039

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No