Abstract
Introduction: To assess the value of MR imaging (MRI) with regard to union, graft viability and proximal pole bone marrow status, after use of vascularized bone grafts (VBG) for treating scaphoid nonunions (SN).
Methods: VBG from the distal radius were used to treat 52 SN. Clinical and imaging evaluation was used for the pre- and postoperative assessment of all patients. Apart of radiographs obtained in all cases, 19 patients were also assessed postoperatively with MRI at 3 months (15 of 19 were assessed preoperatively with MRI) and 15 had serial MRI evaluations (6–12 months). The clinical follow-up time of this subgroup of 19 patients ranged from 6 to 27 months.
Results: All patients showed clinical signs of union within 12 weeks from the procedure. 3-months MRI showed viability of the bone graft in all cases. At 3 months union was established with plain radiographs in 14 patients; plain MRI showed union in 13 patients but contrast-enhanced MRI revealed union in all cases. Eight patients were considered to have osteonecrosis of the proximal pole intraoperatively: 4 showed proximal pole necrosis with postoperative plain radiographs and 5 of them with plain postoperative MRI. Contrast-enhanced MRI at 3 months showed postoperative reversal of necrotic changes in all 8 scaphoids. Serial MRI at 6 and 12 months, revealed resolution of the bone marrow oedema of the surrounding bones and full graft incorporation in all cases.
Conclusions: Contrast-enhanced MRI is able to assess the viability of the proximal pole and to demonstrate the early union after treatment of SN with VBG allowing thus earlier mobilisation.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
