'In-Out-In' K-wires sliding in severe tibial deformities of osteogenesis imperfecta: a technical note.

Severe infant osteogenesis imperfecta requires osteosynthesis. Intramedullary tibia's osteosynthesis is a technical challenge given the deformity and the medullar canal's narrowness. We describe an extramedullary technique: 'In-Out-In' K-wires sliding. We performed an anteromedial diaphysis approach. The periosteum was released while preserving its posterior vascular attachments. To obtain a straight leg, we did numerous osteotomies as many times as necessary. K-wires ('In') were introduced into the proximal epiphysis, and the medial malleolus ('Out') bordered the cortical and ('In') reach their opposite metaphysis. K-wires were cut, curved and impacted at their respective epiphysis ends to allow a telescopic effect. All tibial fragments are strapped on K-wires, and the periosteum was sutured over it. Our inclusion criteria were children with osteogenesis imperfecta operated before 6 years old whose verticalization was impossible. Seven patients (11 tibias) are included (2006-2016) with a mean surgery's age of 3.3 ± 1.1 years old. All patients received intravenous bisphosphonates preoperatively. The follow-up was 6.1 ± 2.7 years. All patients could stand up with supports, and the flexion deformity correction was 46.7 ± 14.2°. Osteosynthesis was changed in nine tibias for the arrest of telescoping with flexion deformity recurrence and meantime first session-revision was 3.8 ± 1.7 years. At revision, K-wires overlap had decreased by 55 ± 23%. Including all surgeries, three distal K-wires migrations were observed, and the number of surgical procedures was 2.5/tibia. No growth arrest and other complications reported. 'In-Out-In' K-wires sliding can be considered in select cases where the absence of a medullary canal prevents the insertion of intramedullary rod or as a salvage or alternative procedure mode of fixation. It can perform in severe infant osteogenesis imperfecta under 6 years old with few complications and good survival time.