Percutaneous Epiphysiodesis Using Transphyseal Screws in Management of Coronal Plane Knee Deformities. A Prospective Case Series

Abstract Background Although many studies reported the efficacy of using percutaneous epiphsiodesis using transphyseal screws (PETS) in correction of coronal plane knee deformities, a lot of them refrained from using this technique because of lack of objective evidence of its reversibility. Methods Twenty-three patient aged from 8 years to 13 years old (40 lower limbs) with coronal plane knee deformity were enrolled into this prospective case series from September 2019 to June 2023. Rate of correction of Mechanical axis deviation MAD, mechanical lateral distal femoral angle mLDFA and medial proximal tibial angle MPTA were measured to prove PETS efficacy. Lower limb length, mLDFA, MPTA were recorded preoperatively and 6 months after screw removal in addition to CT scan of the treated physis to investigate physis behavior and reversibility of the technique. Results The mean MAD correction rate was 3.3 mm/month and 1.78 mm/month for genu valgum and genu varum patients respectively. mLDFA mean correction rate was 1.07 degree/month for genu valgum patients while MPTA mean correction rate was 0.81 degree/month for genu varum patient. No physeal bony bars could be detected 6 months after screw removal for all patients. Conclusion PETS is a highly effective method of hemiepiphysiodesis with rate of correction faster than the other methods of epiphysiodesis. Moreover, it is reliable, reproducible, easy, cheap, more cosmetic, safe and completely reversible when used in juvenile and early adolescent pediatric population