Scaphoid blood flow and acute fracture healing - A dynamic MRI study with enhancement with gadolinium

We have investigated whether assessment of blood flow to the proximal scaph oid can be used to predict nonunion in acute fractures of the scaphoid. We studied 32 fractures of the scaphoid one to two weeks after injury, by dyna mic fat-suppressed T1-weighted gradient-echo MRI after the intravenous admi nistration of gadopentetate dimeglumine (0.1 mmol/kg body-weight). Steepest slope values (SSV) and percentage enhancement values (%E) were calculated for the distal and proximal fragments and poles. All the fractures were tre ated by immobilisation in a cast, and union was assessed by CT at 12 weeks. Nonunion occurred in four fractures (12%), and there was no statistically s ignificant difference between the proximal fragment SSV and %E values for t he fractures which united and those with nonunion. The difference between t he proximal pole SSV and %E values for the union and nonunion groups reache d statistical significance (p < 0.05), but with higher enhancement paramete rs for the nonunion group. Our results suggest that poor proximal vasculari ty is not an important determinant of union in fractures of the scaphoid.