Impact of Predefined Angles and a Revised APPLES Mnemonic on Accuracy and Performance Time for Simulated Ultrasound-Guided Injections

John W. Norbury, William Brader, Michael McIver, Stephen C. Charles, Vivek Sindhi, Kimberly M. Rathbun

Research output: Contribution to journalArticlepeer-review


Objectives Our objective was to determine whether predefined angles would improve performance time and accuracy of ultrasound-guided procedures by novice operators and whether a revised APPLES (approach, position, perpendicular, lift, entry, sweep) mnemonic was a helpful guide for performing the procedure. Methods Participants attempted to hit targets in-plane and out-of-plane at different depths with a needle under ultrasound guidance with and without predefined angles. Participants were then asked if they thought that the mnemonic would be helpful when learning both methods for ultrasound-guided procedures. Results There were 120 participants all of whom had performed fewer than six ultrasound guided procedures. Accuracy increased in all groups when angles were provided; however, only the 3-cm in-plane approach achieved statistical significance. Performance time also achieved statistical significance in two of the four groups. Ninety-five percent of participants thought that the revised APPLES mnemonic would be helpful for learning and performing ultrasound-guided procedures in the future. Conclusions Predefined angles seem to positively impact procedure time and accuracy for some target depths, and the APPLES mnemonic could be a helpful mental checklist for many novice operators. These may be useful tools to facilitate safe and efficient ultrasound-guided procedures in the clinical space.

Original languageEnglish (US)
Pages (from-to)689-693
Number of pages5
JournalAmerican Journal of Physical Medicine and Rehabilitation
Issue number7
StatePublished - 2021
Externally publishedYes


  • Angles
  • Education
  • Interventional Procedures
  • Novice Operator
  • Ultrasonography
  • Ultrasound Guided

ASJC Scopus subject areas

  • Physical Therapy, Sports Therapy and Rehabilitation
  • Rehabilitation


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