Four-Corner Arthrodesis Concentrator of Nickel-Titanium Memory Alloy for Carpal Collapse: A Report on 18 Cases

Abstract

To evaluate the treatment of carpal collapse using a four-corner arthrodesis concentrator of nickel-titanium memory alloy. From August 2006 to August 2010, 18 patients with carpal collapse had scaphoid excision and four-corner (capitate, lunate, triquetrum, and hamate) arthrodesis using a nickel-titanium memory alloy four-corner arthrodesis concentrator. The mean follow-up time was 30 months (range, 12-48). Various wrist parameters, including grip strength, wrist motion, and degree of pain were recorded and compared before and after surgery. The average fusion time was 2.3 months (range, 2-4). Neither nonunion nor wound infection was found in any of the patients. At one year follow-up, the grip strength had reached 80% of that of the healthy side, whereas the range of motion was greater than 50% of the contralateral side. After the surgery, the mean pain scores were improved. Four-corner arthrodesis using a nickel-titanium memory alloy four-corner arthrodesis concentrator effectively treated carpal collapse and preserved most wrist function.