One-stage biplanar osteotomy correction of angulation and shortening deformity of the lower extremity after epiphyseal injury of the distal femur with a monorail external fixator / 中华实用儿科临床杂志

ABSTRACT

Objective:To investigate the clinical effectiveness of one-stage biplanar osteotomy correction of angulation and shortening deformity of the lower extremity after epiphyseal injury of the distal femur with a monorail external fixator.Methods:The data of 5 patients (2 males and 3 females) with angulation and shortening deformity in the lower extremity after epiphyseal injury of the distal femur were retrospectively analyzed.The patients underwent monorail external fixator assisted one-stage osteotomy correction of the distal femur and distraction osteogenesis of the middle and upper femur in Zhengzhou Orthopeadics Hospital from May 2017 to December 2019.The mean age was 13.6 years old (range: 10 to 17 years old). The affected limbs were shortened by 5.1 cm on average (range: 3.9 to 6.5 cm). The average angulation deformity of the distal femur was 24.9° (range: 17.0°to 30.5°). The mechanical lateral distal femoral angle (mLDFA), the mechanical posterior distal femoral angle (mPDFA), the mechanical axis deviation (MAD), the range of motion (ROM) of the knee, and the length of the lower limbs before surgery and at the final follow-up were measured and analyzed.Results:All patients were followed up for 22 months on average (range: 15 to 32 months). For all the 5 patients, the mechanical axis was well realigned, mLDFA, mPDFA, and MAD returned to normal range, and the length of the affected limb achieved the goal as planned before the surgery.Besides, the affected limbs were lengthened by 5.6 cm on average (range: 3.9 to 8.0 cm), and the median healing index was 35.6 d/cm (range: 29.0 to 45.0 d/cm). The bone callus in the distraction area and the osteotomy end were well healed at the final follow-up, as indicated by the X-ray results.At the end of the distraction period, the flexion ROM of the knee in all patients reached basically 90°.By the final follow-up, all patients had a normal knee ROM.No vascular or nerve injury, dislocation of hips or knee joints, re-fracture after disassembly, deep infection and other complications were observed in all patients.Conclusions:One-stage biplanar osteotomy correction of angulation and shortening deformity of the lower extremity after epiphyseal injury of the distal femur with a monorail external fixator is safe and feasible.The method requires no multiple operations and improves the tolerance of patients during the treatment period.