Purpose: To report the complication of carpal bone tunnel collapse in scapholunate reconstruction. Methods: The authors present six cases of carpal collapse or bone necrosis after bone tunneling for ligamentous reconstruction, three in the scaphoid bone and three in the lunate. Results: All six cases were secondary to ligament reconstruction for chronic scapholunate dissociations, none of which had preoperative structural scaphoid or lunate deformities. Conclusions: Although the incidence of this occurrence is unknown, the consequences could be substantial; therefore, patients should be warned of this possibility when discussing complications of ligament reconstruction for chronic scapholunate instability requiring the creation of a bone tunnel. Type of study/level of evidence: Therapeutic V.