The Learning Curve and Pitfalls of Arthoscopic Four-Corner Arthrodesis

Abstract

Midcarpal “four-corner” wrist arthrodesis is a motion-sparing salvage procedure mainly employed for painful wrist osteoarthritis. In the procedure the scaphoideum is resected along with midcarpal joint surfaces after which lunatum, triquetrum, capitate and hamate are fused together. Unlike total wrist fusion, the operated wrist maintains around 50% of its movement compared to the contralateral wrist. Currently the procedure may be done from an open arthrotomy or arthroscopically. This study aimed to examine the results of the recently described arthroscopic four-corner arthrodesis and whether the procedure seems to have any merit compared to the open technique. Eight patients were retrospectively identified with nine cases of arthroscopic four-corner arthrodesis performed at Turku University Hospital 2014-2017. Operating time for the first surgery was 198 minutes while the final one lasted 132 minutes. All patients achieved fusion. Three patients required a reoperation: one for screw malposition with screw removal, one for tendon reconstruction and screw removal due to a tendon injury induced by a retracted screw and one for scaphoid impingement with removal of the scaphoid remnants. One patient experienced a probable superficial radial nerve injury. The arthroscopic approach is technically extremely demanding and has a learning curve. Thorough resection of the scaphoid and careful placement of screws is recommended to avoid potential complications.