Wide-awake ultrasound-guided percutaneous extensor central slip tenotomy for chronic mallet finger: A prospective study of 14 cases (with videos).

The central slip tenotomy described by Fowler is an effective option for treating chronic mallet finger in order to avoid swan neck deformity of the finger. In a prospective study of 14 cases (13 failures of conservative treatment and one case of untreated mallet finger), we performed percutaneous ultrasound-guided central slip tenotomy with a 19 G needle using the wide-awake local anesthesia and no tourniquet (WALANT) technique. The mean extensor lag before surgery was 28° (range 20°-40°) and three patients had a swan neck deformity. The anesthesia and tenotomy were guided with a 15MHz high frequency probe. Patient were asked to grade their pain between 0 (no pain) and 10 (extreme pain) with a Visual Analog Scale (VAS), to flex and extend their finger immediately after the tenotomy and to be reviewed at 1month's follow-up. The mean pain score on VAS during the procedure was 1/10 (range 0-3). After several movements of the finger after the procedure, two patients immediately regained full extension of the distal interphalangeal joint. At 1month follow-up, the correction was complete for 10 patients, three patients had a residual deformity of 10° and one had a poor result with a 30° deformity. Two patients had a persistent painless synovitis of the proximal interphalangeal joint. Thirteen patients were fully satisfied and one was a disappointed, but did not want another treatment. There are no published reports of percutaneous central slip tenotomy. In this preliminary report, central slip tenotomy for chronic mallet finger with ultrasonography was painless, effective and safe under WALANT technique. Larger clinical studies are needed to confirm the outcomes of this study.