Osteonecrosis of the Lunate Following Three-Corner Arthrodesis: A Case Report.

Scaphoid lunate advanced collapse (SLAC) is the most frequently encountered cause of wrist osteoarthritis. Proximal row carpectomy (PRC) and four-orner arthrodesis (4CA) are the two main surgical options to address it. Three three-corner arthrodesis (3CA) was introduced in 1997 as an alternative to PRC and 4CA. It is a motion preserving midcarpal arthrodesis easier to perform than 4CA, for which the literature has documented satisfactory outcomes and low complication rates. We report a case of a SLAC wrist treated with 3CA complicated by postoperative osteonecrosis of the lunate. To our knowledge, this complication has not been previously reported. Our patient developed osteonecrosis of the lunate 1 year after 3CA despite a good consolidation of the arthrodesis. In this case study, we discuss reasons this may have occurred, the aetiology of which is likely multifactorial. We are reporting this case to inform surgeons of this potential complication after 3CA. Level of Evidence: Level V (Therapeutic).