Clinical results of the BoneWelding®Fiji® anchor for the treatment of Stener lesions of the thumb

INTRODUCTION: A new technology (Sportwelding®) was recently presented, which uses ultrasonic energy to meld a resorbable suture anchor at the interface with the host bone. A standardized clinical use was not investigated yet. This study prospectively evaluated the surgical and clinical outcomes of the Fiji Anchor® (Sportwelding®, Schlieren, Switzerland) in the repair of an ulnar collateral ligament lesion of the metacarpophalangeal joint of the thumb. MATERIAL AND METHODS: The range of motion, grip and pinch strength, disability of arm, shoulder and the hand (DASH) and patient rated evaluation (PRWE) score, pain, satisfaction, complications and adverse events were assessed in 24 patients after surgical treatment for an acute displaced rupture or avulsion of the ulnar collateral metacarpophalangeal ligament of the thumb using the Fiji Anchor® after 6, 12 and 52 weeks. RESULTS: At final follow up, the range of motion of the metacarpophalangeal joint reached almost the contralateral side (49.3° SD 11.7°). Thumb opposition showed a Kapandji score of 9.7 (SD 0.5; range 9–10). Grip strength, the lateral, tip and the three jaw pinch showed nearly similar values compared to the contralateral side (83–101%). Pain was low (0.2 SD 0.7 at rest and 0.6 SD 1.0 during load). The DASH score was 5.0 (SD 7.3) and the PRWE score was 4.1 (SD 9.0). 81% of patients were very satisfied at final follow-up. Two patients were rated unstable during the follow-up period due to a second traumatic event. Three cases experienced difficulties during anchor insertion, whereby incorrect anchor insertion resulted in damage to the suture material; however, this was resolved after additional training. CONCLUSION: One advantage of this anchor appears to be its stable fixation in cancellous bone. The surgical treatment of an ulnar collateral ligament lesion of the thumb using the Fiji Anchor® can lead to an excellent clinical outcome with a minor complication rate; however, long-term dangers and the cost effectiveness of the procedure are not known yet.