Step-cut osteotomy for cubitus varus deformity with application of patient-specific instrument in children: a preliminary report

PurposeThe step-cut osteotomy has been recognized as a valuable approach for addressing cubitus varus deformity, albeit one that necessitates technical proficiency. This study aims to evaluate the efficacy of the modified step-cut osteotomy technique in conjunction with patient-specific instruments by clinical and radiological assessment.MethodsWe conducted a retrospective review of patients who underwent modified step-cut osteotomy with the use of patient-specific instruments in conjunction with Kirschner wires fixation for the correction of cubitus varus deformity between April 2016 and April 2022. Follow-up was performed for a minimum of two years, during which pre-operative and post-operative clinical and radiological parameters were compared.ResultsFifteen patients were enrolled in this study. The mean pre-operative humeral-elbow-wrist (HEW) of the affected side was -21.7 degrees (ranging from -14 degrees to -34 degrees), while the normal side was 9.4 degrees (ranging from 5 degrees to 15 degrees). The post-operation HEW of affected side was 9 degrees (ranging from 4 degrees to 16 degrees). There was no significant difference between the normal side and affected side after operation (p = 0.74). Pre-operative range of motion in the affected side was 130 degrees, while the post-operative range of motion was 132 degrees. Fourteen patients (93.3%) were pleased with the overall appearance of their elbow. None lazy-S deformity was observed in these cases. There were no major complications.ConclusionThe modified step-cut osteotomy technique, utilizing patient-specific instrument in conjunction with Kirschner wires fixation was found to be a safe, reliable, and technically easy procedure for correcting cubitus varus deformity.