Magnetic resonance imaging findings and treatment outcome in late-onset tibia vara.

Several retrospective studies have shown the usefulness of magnetic resonance imaging (MRI) in the evaluation of tibia vara. With respect to the late-onset type, however, there have been no English-language reports on MRI findings. In this article, the authors report on the MRI features of three patients with late-onset tibia vara, the results of treatment that was chosen on the basis of the findings, and the histologic characteristics of the disease. Fat-suppressed MRI revealed partial closure of the tibial physis in one patient and near-closure in another patient. They underwent osteotomy with resection of the bone bridge and have shown no evidence of recurrence. In the third patient, only irregularity of the physis was found on MRI, and she was treated conservatively. Her varus deformity subsequently improved, although it persisted. Histologic examination revealed disorganization and misalignment of the physeal zone and transverse alignment of the trabeculae. The patient with a bony bridge also had discrete ossification centers in the physeal zone.