Rebound predictors of varus-valgus deformities around the knee corrected by guided growth.

PURPOSE: Coronal plane deformities around the knee are rather common condition in children. Guided growth by temporary hemiepiphysiodesis is considered to be the preferred primary treatment in many cases. Despite the popularity of hemiepiphysiodesis, the incidence of recurrence of deformity and predictors for rebound are not well defined. The objectives of this study were to determine the incidence of the recurrence of varus-valgus deformities around the knee treated by temporary hemiepiphysiodesis and possible predictors for the rebound. METHODS: We retrospectively reviewed medical records and x-ray images of 130 patients with varus-valgus deformities around the knee treated by tension-band (eight-plate) hemiepiphysiodesis, between the years 2006 and 2016 in our institution. The incidence of rebound of varus-valgus deformities around the knee and possible predictors were analyzed. RESULTS: Rebound of the deformity was observed in 10% of patients. Risk factors found to be in correlation with recurrence include young age, deformity of proximal tibia, proximal tibial medial growth plate beaking, and comorbidities (like metabolic disorders, multiple hereditary exostoses and genetic syndromes). CONCLUSION: The results of this study show that there is a noteworthy incidence of rebound in patients treated by temporary hemiepiphysiodesis for coronal deformities around the knee. The risk factors are also outlined. These patients, especially the ones with risk factors, require close surveillance until maturity. LEVEL OF EVIDENCE: Level III-Case control study.