Osteonecrosis in the lunate bone in the presence of palmar lunate dislocation in rheumatic patients

Abstract

This study aims to assess the relationship between rheumatic disorders with palmar lunate dislocations and lunate osteonecrosis (ON). From 2004 to 2016, we prospectively studied 24 wrists with advanced rheumatic disease in which the lunate was chronically dislocated palmarly, situation that clearly favors the apparition of ON. There were 18 female and 6 male with a mean age 64 (52-79) years old. The surgical treatment was wrist arthrodesis in 19 cases and wrist arthroplasty in 5. We evaluated X- ray data and we correlated preop X-ray, blood test parameters and MRI data with histopathological findings. Statistical analysis of data was performed with Chi square test and Student´s t-test (significance level p ≤ 0.05). We found a focal lunate necrosis in two cases. We did not find a statistically significant correlation between ON and lunate dislocation (p= 0.793). We did not find any blood test parameter statistically significant associated with ON (p= 0.621). Despite the possibility to developing ON of the lunate bone in presence of palmar lunate dislocation in patients with rheumatic wrist, angiogenesis and synovitis formed could have a role in chronic adaptation to the loss of vessels in the lunate.