Hemicallotasis opening wedge osteotomy for correction of proximal tibial deformities

ABSTRACT

Hemicallotasis opening wedge osteotomy [HCO] was used in this study to treat 23 patients with varus deformity of the proximal tibia. The indications for treatment were primary medial compartment osteoarthritis in 18 patients and adolescent Blount disease in 5 patients. The mean age in the osteoarthritis group was 47.8 years and 12.9 years in the Blount disease group. The total time in fixator averaged 87 days. The mean follow-up period was 22.8 months. The mean preoperative tibiofemoral angle in all patients was 8.7 degrees of varus. Mean angular correction for all patients was 11.8 degrees. The mean correction was 17.3 degrees in patients with Blount disease and 9.9 degrees in the osteoarthritis group. Optimal correction to 4 +/- 2 degrees of valgus was achieved in 18/23 patients. Three patients had under correction and two had over correction. The mean Oxford knee score among the osteoarthritis group was 33.9 points. Complications included deep venous thrombosis in one patient, delayed union in one patient, minor pin tract infection in eight patients and one patient required readjustment of the external fixator. There were no neurological or vascular complications. This work showed that HCO technique has the advantages of allowing more precise correction of the deformity with fewer complications when compared to the classic techniques