Lunotriquetral coalition, a normal variant that may rarely cause ulnar sided wrist pain

Lunotriquetral coalition (LTC), the most frequent and often bilateral type of carpal coalition, is in general considered as asymptomatic. In rare cases – however – fibrocartilaginous LTC may be an uncommon cause of ulnar sided pain in the wrist due to the pseudarthrosis or a post-traumatic disruption of LTC. Two rare cases of symptomatic LTC are presented and the role of MRI is emphasized. MRI shows the pseudarthrosis and may additionally show bone marrow edema and subcortical cysts. In symptomatic cases surgical lunotriquetral fusion may be considered as treatment option.