Accuracy of rib palpation for dry needling of deep periscapular musculature,measured with ultrasound

IntroductionDry needling of the periscapular musculature is a procedure commonly performed by physical therapists. Needling of the deep musculature may be challenging, and use of a thoracic rib as a “backstop” is often applied to prevent inadvertent puncture of the pleura. The aim of this study was to: 1) To examine the accuracy rate of experienced physical therapists in identifying a mid-scapular thoracic rib using palpation, 2) to understand patient characteristics that affect the accuracy rate, and 3) to examine if therapist confidence levels were associated with palpatory accuracy.MethodsTwo experienced physical therapists attempted to palpate a thoracic rib in the mid-scapular region of healthy participants (n = 101 subjects, 202 ribs), and self-reported their level of confidence in an accurate palpation. Their accuracy was verified with ultrasonography.ResultsThe two physical therapists were accurate on 73.3% of palpations and did not differ in accuracy (72.0% vs. 75.0%, p = 0.747). The only ultrasonographic or subject characteristic measurement that correlated with improved accuracy was a reduced muscle thickness (p = 0.032). Therapists’ self-reported confidence levels did not correlate to actual accuracy (p = 0.153).DiscussionPhysical therapists should be aware that palpation of a thoracic rib may not be as accurate as it may seem. The greater thickness of muscle in the area reduces the accuracy of accurate palpation.ConclusionDry needling of the periscapular muscles should be done with caution if using a rib as a “blocking” technique.