UPPER METAPHYSEAL LENGTHENING OF THE TIBI A BY CALLOTASIS - A REPORT OF 57 CASES IN CHILDREN AND ADOLESCENTS

Introduction The authors reviewed 57 upper metaphyseal lengthenings of the tibia. They especially studied complications in order to evaluate this method. Material and methods Fifty seven tibial lengthenings in 47 children and adolescents were reviewed. All lengthenings were perfo rmed according to the callotasis technique, using Judet's lengthener i n the first 15 cases, the, OF-Garches Orthofix(R) in 42 cases. All the callotasis principles were applied: delayed elongation, 1 mm per day distraction, one month neutralization after elongation period, then dy namization before removing the apparatus. Particularities were: a) met aphyseal osteotomy of the upper tibia, b) screw fixation and osteotomy of the fibula, c) classical dynamization according to De Bastiani and Aldegheri in 29 cases, dynamization by a silastic collar (OF-DynaRing (R)) in 28 cases. Methods Severity of complications was classified acc ording to Caton: none, benign, serious (needed reoperation or reanesth esia) and severe (sequel). Complications and rate of lengthenings with out complication or with benign complications were studied relative to etiology, age, amount of lenghtening and the stage of program in whic h they occurred. A table summarizes data of all the lengthenings. Resu lts Lengthening was 52.3 mm in average. Healing time (number of days t o lengthen and to fuse the bone divided by the number of lengthened ce ntimeter) was 40 in average (range: 20-105): it was 45.6 days per cm w hen using classical dynamization and only 34.3 with silastic collar dy namization (p = 0.002). Total of complications was 59 out of 57 length ening. 21 complications were benign, 37 serious and 1 severe (partial motor palsy of the foot). Thirty two (56 per cent) lengthenings were p erformed without unforeseen procedure or anesthesia. There were 4 intr a-operative complications: 1 vascular lesion, 1 incomplete osteotomy a nd 2 malpositioned half screws. Complications of elongation period wer e the most numerous, 4 transient palsies, 6 knee contractures (2 led t o a supracondylar fracture), 6 equinism (4 needed an Achilles tendon l engthening), 12 valgus deviations in which 9 were realigned using OF-G arches fixator without reoperation, 1 serious depression occurred in a bilateral lengthening. Consolidation was achieved without complicatio n in 52 cases. Complications were: 1 refracture (fourth lengthening of the same tibia), 1 delayed union, 1 non-union, 2 late deviations. Dis cussion Rate of nervous and joint complications is close to that of ot her series. However, a high osteotomy decreases the consequences on th e foot without increasing knee contracture in flexion. The ability to realign during the elongation period appears to be a prevention of val gus deformity compared to Wagner's technique. The author's distractor is better tolerated than llizarov's. Problems with consolidation are r are, less than 9 per cent of the cases. Conclusion A modular distracto r improves the results of tibial lengthening; realignment is possible before, during or after the elongation. OF-Orthofix(R) is easy to appl y and well-tolerated by the patient, especially in bilateral lengtheni ngs. Performing a high osteotomy, the callus is thick and the consolid ation is quickly achieved and safe. A well-thought dynamization using Orthofix Dyna-Ring(R) decreases the treatment time which is 35 days pe r centimeter in average.