Clinical efficacy of Ni-Ti memory alloy four-corner arthrodesis concentrator in the treatment of scaphoid nonunion advanced collapse: a follow-up of over 10 years.

Purpose: Exploring the therapeutic effects of Ni-Ti shape memory alloy four-corner arthrodesis concentrator (NT-FCAC) in treating scaphoid nonunion advanced collapse (SNAC) and providing a decade-long follow-up report.

Materials and methods: Twenty-six patients with SNAC underwent scaphoidectomy, along with four-corner arthrodesis fusion involving the capitate, lunate, triquetrum, and hamate, using NT-MFCAC. Grip strength was measured using a Jamar dynamometer, while wrist joint mobility was assessed using a goniometer. Preoperative and postoperative assessments were conducted using the Quick Disabilities of the Arm, Shoulder, and Hand (Quick DASH) questionnaire to monitor limb functionality restoration. Pain levels at the wrist joint were evaluated using the visual analog scale (VAS). Postoperative wrist bone fusion status was assessed through anteroposterior and lateral radiographs of the wrist joint.

Results: After a 3-month postoperative period, all 26 patients exhibited osseous union at the wrist joint. Over a follow-up spanning 10-15 years, no severe postoperative complications were observed in any patient. Grip strength in the affected side of all patients recovered to 81.96% compared to the healthy side, while wrist joint mobility in the affected side reached over 60% of the healthy side's functionality. VAS scores decreased significantly from 5.85 ± 0.73 preoperatively to 0.19 ± 0.40 at the final follow-up; Quick DASH scores reduced from 69.88 ± 5.12 preoperatively to 6.30 ± 1.25 at final follow-up. Statistically significant differences were noted in VAS and Quick DASH scores for all patients (p < 0.05). However, beyond 60 months postoperatively, subsequent follow-ups did not yield statistically significant differences in VAS and Quick DASH scores for all patients (p > 0.05).

Conclusions: Utilizing NT-FCAC for SNAC treated with four-corner arthrodesis fusion results in a high rate of wrist bone fusion, preserving a significant portion of wrist joint function and exhibiting favorable long-term outcomes. This approach is suitable for treating patients with SNAC requiring four-corner arthrodesis fusion.