ADOLESCENT TIBIA VARA - ALTERNATIVES FOR OPERATIVE TREATMENT

We reviewed the cases of fifteen obese patients (twenty-one extremities) who had had adolescent tibia vara and had been followed for at least two years. Of the nine patients (eleven extremities) who had been initially managed with lateral tibial hemiepiphyseodesis, eight (ten extremities) were skeletally mature at the time of the review (mean duration of follow-up, five years). The mechanical alignment was judged to be excellent in three of these ten extremities, fair in three, and poor in four. Excellent mechanical alignment was defined as a value within the reported normal range of 5 degrees of varus to 2 degrees of valgus. A poor result was defined as alignment that was more than 5 degrees outside the normal range. After secondary operative procedures, three of the extremities for which the result had been poor and one for which it had been fair had excellent alignment. Five of the nine patients had bilateral involvement. Two of them were managed with bilateral tibial hemiepiphyseodesis; two, with contralateral proximal tibial osteotomy; and one had a mild deformity on the contralateral side that was not treated. Six extremities in six patients (two of whom had a contralateral hemiepiphyseodesis) were managed primarily with proximal tibial osteotomy and were evaluated an average of seven years postoperatively. Two additional patients were managed with proximal tibial osteotomy because of residual varus deformity after the hemiepiphyseodesis. The mechanical alignment at the time of the most recent follow-up was judged to be excellent in three of these eight extremities, fair in two, and poor in two; the alignment could not be determined in one patient who had died from an unrelated problem. One patient in this group had a mild contralateral deformity, which was not treated. Tibial osteotomy was a difficult procedure in these very obese patients, and it was associated with a high rate of complications. Secondary operative procedures were frequently needed both after hemiepiphyseodesis and after proximal tibial osteotomy. Two patients who had unilateral disease were not operated on. One of them refused operative treatment, and the other had a mild deformity that did not worsen with additional growth. A high prevalence of complications and malalignment after tibial osteotomy was found in this series. The results of lateral tibial hemiepiphyseodesis, while not uniformly excellent, make it a reasonable alternative to osteotomy for patients who have adolescent tibia vara and open proximal tibial physes.