In treatment of scaphoid nonunions age of nonunions, stability of reconstructions and particularly vitality of proximal fragments are regarded as important prognostic factors for healing. The value of preoperative MRIscans in predicting intraoperative vitality and final osseous union prospectively was investigated. Scaphoid nonunions in 60 patients (7 female, 53 male, mean age 30 years) primarily were reconstructed between 1/2000 and 7/2003. Preop they underwent a standardized MRIscan using i.v. Gadolinium to assess vitality of proximal fragments. The scaphoids were reconstructed per palmar or dorsal approach implanting nonvascularized iliac-crest or distal radius bone grafts stabilized with cannulated or mini Herbert screws. Intraop vascularity (vital/nonvital) was documented estimating blood spots occurring on the debrided fragments cancellous surface (none/medium/many). After immobilization for 6–8 weeks osseous union was ruled out performing repeated radiographic and CT studies up to 6 months. Apart from demographic data, age and type of nonunion, intraop fragment vitality and postop osseous union were correlated to vitality stated in preop MRIs. A p-value of 0.5 was regarded as significant. 50 proximal fragments preoperatively were stated vital. Overall fragment vitality was predicted correctly in 52 patients. 5 were false negative, 3 false positive. No significant correlation between age or type of nonunion and the predicted vitality could be obtained. Osseous union was gained in 55 scaphoids. Patients with predicted avital fragments had no significantly higher incidence of osseous union than those with avital fragments. Preop MRIscans are of value in detecting avascular proximal fragments in scaphoid nonunions. In these cases reconstruction with vascularized bone grafts is proposed. Our data however indicate that vascularity of proximal fragments is not predictive of bony healing. High rates of osseous union can be achieved even with nonvascularized grafts in pateients having avascular proximal fragments.
