Gradual bilateral genu varum correction in skeletal dysplasia using the Ilizarov method

Abstract

Options for lower limb realignment in skeletal dysplasia are acute versus gradual correction, internal versus external fixation, and external fixation with or without intramedullary nailing. The safety and versatility of the Ilizarov method in skeletal dysplasia patients makes it a procedure of choice. We describe here our experience with this procedure with 48 skeletal dysplasia patients, with a mean age of 15 years, and a minimum follow-up of 2 years. Preoperative, postoperative, and latest follow-up measurements of tibia-femur (T-F) angle, conventional mechanical axis deviation (MAD-C), ground mechanical axis deviation (MAD-G), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), posterior distal femoral angle (PDFA), and posterior proximal tibial angle (PPTA) were compared. The mean lengthening amount (LA) was 7.4 cm, mean lengthening percentage (LP) was 35.5%, mean external fixation index (EFI) was 28 days/cm, and mean healing index (HI) was 35 days/cm. Mean MAD-C and MAD-G correction were 9.3 mm and 11.8 mm, respectively. T-F angles, PPTA, MAD-C, and MAD-G were significantly improved. Equinus deformity was the most prominent obstacle, and varus recurrence was the most frequent sequela. In most skeletal dysplasia patients, lower limb realignment with gradual deformity correction using the Ilizarov method may be a reliable option. Equinus deformity occurs in those with more than 40% lengthening, but can be easily corrected. In addressing varus recurrence after gradual correction, the intrinsic and extrinsic factors should be sought first then treated accordingly.