Correction of knee deformities with Ilizarov fixator

Abstract

Objective To explore the clinical characteristics and outcome of correction with Ilizarov fixator for the knee deformities.Methods From May 2003 to April 2010,21 patients (22 knees) underwent knee deformity correction with Ilizarov fixator,including 12 males and 9 females with an average age of 20.3 years (range,8-48).Causes of the deformities included poliomyelitis in 4,burn in 2,osteomyelitis in 2,trauma in 9,Blount diseases in 2,and multiple osteochondromatosis in 2.Five patients had fixed flexion contracture due to soft tissue,they were corrected through a combination of Ilizarov's frame crossover the joint with a pair of hinges by gradual posterior distraction.Eight patients (9 limbs) had one way bony deformities and 7 patients had complex deformations.The frame with 4 hinge-posts was used for correction by restoring the alignment firstly,and then gradual lengthening to correct bone shortening.Additionally,an overlay frame of the above mentioned combinations was applied for correction of bony deformity combined with soft tissue contracture for 1 patient.Results The average time in frame was 22.3 weeks (range,12-36).At the time of removing frame,satisfactory alignment was achieved in all of the affected knees,and solid bony healing was obtained in osteotomy or bone lengthening area in 16 patients (17 limbs) with bony correction.All patients were followed up for an average of 32.1 months (range,6-86).The range of motion was improved from 102.14°±49.36° preoperatively to 126.90°±24.31° at the final follow-up.Additionally,the Japanese Orthopaedic Association knee score was also increased from 50.24±23.64 before operation to 85.71±10.52 at the final follow-up.All of them were able to walk without crutches,deal with daily life independently.Only 2 patients with the range of motion of the knee less than 90° were not able to squat.Conclusion Ilizarov fixator has advantages of minimal intervention to local tissue in operation and nimble adjustment at any time,and disadvantages related to a longer time in frame. Key words: Knee joint; Abnormalities; Ilizarov technique