The Advantages of Type III Scaphoid Nonunion Advanced Collapse (SNAC) Treatment With Partial Carpal Arthrodesis in the Dominant Hand: Results of 5-year Follow-up.

Introduction: The SNAC wrist (Scaphoid nonunion advanced collapse) is one of the complications following scaphoid fractures treated conservatively and one of the causes of wrist arthritis that the hand surgeon has to face most frequently. In these cases surgical management is usually warranted.

Materials and Methods: In the set time frame of 6 years we treated 15 SNAC wrist cases. On average patients underwent surgery five years after the trauma. All patients were treated via dorsal incision with partial carpal arthrodesis and total scaphoidectomy, associated with denervation of the posterior interosseous nerves. A plaster cast was applied to all patients for 3 weeks postoperatively. In the preoperative stage, X-rays of the healthy contralateral limb were taken for the measurement of the normal radiocarpal joint space. Clinical and radiographic follow-ups were conducted at 1,3, 6 and 12 months from the trauma; then every 12 months. Criteria for the evaluation of patients: visual analog pain scale (VAS), average time of radiographic fusion of wrist bones, Active Range of Wrist Motion (WAROM), subjective Mayo Wrist Score (MWS) and The Short Form ( 36) Health Survey (SF-36), return to the main tasks and complications. The evaluation endpoint was set at 60 months. Average time of surgery: 48.3 minutes. Average time of arthrodesis consolidation: 67.8 days. The VAS and WAROM showed a gradual improvement in seriated controls, returning to values almost identical to pre-trauma at a 5-year follow-up. By this time, the MWS and SF-36 scores were similar to pre-trauma. On average, the return to pre-injury daily activities occurred in 12.5 months after surgery. There were no complications.

Conclusions: The partial carpal arthrodesis is a safe and effective procedure for the treatment of SNAC wrist cases. Our results show a progressive and significant improvement in ROM, VAS and great satisfaction from the patient.