Twenty-two patients with fracture of the scaphoid treated by cast immobilis
ation underwent clinical examination, radiography and MR scanning 6 weeks a
fter injury. On clinical and plain radiographic criteria alone, 12 patients
were considered sufficiently healed to warrant mobilisation. The remaining
10 patients were considered unhealed and were immobilised for a further pe
riod. A musculoskeletal radiologist, blinded to the clinical diagnosis, rev
iewed the MRI scans. Of the 10 patients considered unhealed, 5 had the MR a
ppearances of a united fracture based on normal marrow signal across the fr
acture line on T1-weighted images. Of the 12 patients deemed to have united
, union could be confirmed by MRI criteria in only 5, but all 12 were heale
d at 1 year. The results suggest that MRI can provide additional informatio
n in this group of patients. It can confirm bony union in a high proportion
of patients deemed clinically non-united. Its use in this context will all
ow a more rapid mobilisation and return to normal function.,The significanc
e of persistent MR signal abnormalities in patients who have clinical and r
adiographic signs of healing merits further study.