A Novel Mini-Invasive Technique of Arthroscopic-Assisted Reduction and Robot-Assisted Fixation for Trans-Scaphoid Perilunate Fracture Dislocations.

Objective: Perilunate injuries are rare but devastating carpal injuries. The treatment of perilunate injuries remains challenging and contentious. This study aims to describe a novel mini-invasive surgical technique of arthroscopic-assisted reduction and robot-assisted fixation for the treatment of trans-scaphoid perilunate fracture dislocations (PLFDs).

Methods: We retrospectively reviewed patients with PLFDs after surgical treatment from February 2021 to March 2021. The patients underwent arthroscopic-assisted precise reduction and robot-assisted headless screw fixation. Times of guide wire placement were recorded intraoperatively. Periodic follow-up was performed until union of scaphoid fracture was confirmed. Range of motion of the wrist, grip strength, the Visual Analog Scale (VAS) score, the Mayo Wrist Score, the Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH) score, the Patient-Rated Wrist Evaluation (PRWE), and osteoarthritis were evaluated at the final follow-up.

Results: Two male patients presenting with PLFDs with an average age of 24.5 years old (32 and 17 years) were included in this study. Intraoperatively, anatomic reduction of the scaphoid fracture was achieved under arthroscopic guidance. A robotic-assisted single-attempt guidewire insertion was performed for scaphoid fracture and lunotriquetral interval. The CT scans at 8 and 12 weeks showed the union of the scaphoid fracture. At final mean follow-up of 13.5 months, the extension, radial-ulnar deviation, and pronation-supination were consistent with the contralateral side in both patients. One patient experienced mild limited range of motion with the flexion 46° of the injured wrist compared with 81°of the contralateral wrist. The VAS score was 0 and 2. The grip strength was 32 and 26 kg compared with 24 and 42 kg of the contralateral wrist. The PRWE score was 13 and 10 and the QuickDASH score was 2 and 7. The Mayo Wrist Score was 100 and 65. No sign of osteoarthritis was found at the last follow-up.

Conclusions: Arthroscopic-assisted reduction and robot-assisted fixation is a viable and promising alternative for the treatment of perilunate fracture dislocations. This technique allows precise reduction and accurate placement of the K-wires/screws into the carpal bones through the optimal biomechanical paths.