Correction of bony deformities around knee by hemicallotasis using an innovative apparatus

Background: Valgus and varus deformities around the knee are common. Various osteotomies and apparatuses have been described to correct these deformities. Methods: Bony deformities around knee joint in thirty patients (36 joints) were corrected by osteotomy in upper tibia or lower femur which was stabilized and distracted with innovatively designed and locally fabricated T-shaped external fixator-cum-distractor. The age of the patients ranged from 5 to 48 years. The causes of deformities were post-traumatic (18), rickets (5), tibia vara (3), idiopathic (3) and Ollier′s disease (1). The deformity was in lower femur in 14 cases and upper tibia in 16 cases. Sixteen patients had genu varum, 13 genu valgum and one patient had post traumatic tackle (wind-sweep) deformity i.e. genu varum one side and valgum on the opposite. Results: Good results were achieved in 27 cases (32 joints) as deformity was fully corrected with full range of painless post-operative movement (follow up 2-8 yrs). Superficial pin-tract infection was the main but temporary complication particularly in summer and rainy season. Conclusion: The apparatus was found quite useful in stabilizing as well as differentially distracting the osteotomy i.e. hemicallotasis to achieve desirable amount of correction of deformities.