Quick and Easy Correction of a Symptomatic Pincer Nail Using a Shape Memory Alloy Device

BackgroundPincer nails are characterized by the transverse curvature increasing from the proximal to the distal aspect along the longitudinal axis. A novel treatment technique using a shape memory alloy device was recently introduced. ObjectiveTo determine the treatment outcomes and safety of a shape memory alloy device. Methods and MaterialsThis was a retrospective analysis of 21 cases of pincer nail of the great toe in 14 patients. Subjective indices (pain, inconvenience, global assessment scores) and objective parameters (transverse angle, width index) on days 0 (D0) and 1 (D1) and weeks 2 (W2) and 12 (W12) were investigated. ResultsAll parameters started to show significant improvement on D1. From D0 to D1, pain score fell from 3.61.0 to 1.5 +/- 0.7, inconvenience score fell from 3.3 +/- 1.0 to 1.5 +/- 0.7, global assessment score increased from 1.5 +/- 0.7 to 2.5 +/- 0.7, transverse angle improved from 86.4 +/- 27.7 degrees to 114.7 +/- 21.6 degrees, and width index improved from 67.6 +/- 13.1% to 89.0 +/- 9.7%. These effects were consistent during 12weeks of follow-up. Two cases (9.5%) recurred, but symptoms were less severe than before. No complication was identified. ConclusionA shape memory alloy device was an effective and safe way to rapidly correct symptomatic pincer nail deformity.