Investigating a No-Cost, Noninvasive, Patient-Driven Approach to Pain Reduction for Trigger Finger Injections - A Randomized Controlled Trial.

PURPOSE: To evaluate whether patient-controlled scratching of the skin proximal to the injection site in the relevant cervical dermatome is associated with a reduction in pain caused by corticosteroid injection for trigger finger compared to no scratching or scratching of the contralateral limb.

METHODS

A total of 105 patients presenting with trigger finger were enrolled in this prospective, single-blind, randomized controlled study. Patients were randomly assigned to one of three groups: control (no intervention), distraction (cognitive/motor distraction task with patient-controlled scratching of the shoulder contralateral to the injected digit), and experimental (patient-controlled scratching of the ipsilateral upper extremity within the cervical spinal dermatome corresponding to the injected digit). Before injection was performed, anticipated pain was measured with a visual analog scale (VAS), and pain catastrophizing scale (PCS) surveys were completed. Postinjection, experienced pain was measured with a second VAS score.

RESULTS

The experimental condition resulted in a statistically and clinically significant reduction in experienced pain compared to the control condition (means = 59 vs 28 on VAS, respectively). There were also clinically significant differences in mean VAS scores between control and distraction groups (59 vs 43) and between distraction and experimental groups (43 vs 28). Only the experimental condition resulted in a significant reduction in experienced pain compared with anticipated pain.

CONCLUSIONS

Patient-controlled scratching of the skin of the forearm within the same cervical dermatome as the injection site results in clinically significant pain reduction during injection administration. Although purely cognitive distraction may exert nonspecific effects to attenuate the conscious experience of pain, tactile stimulation in the relevant dermatome appears to be more effective.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic 1b.