Supracondylar osteotomy of the humerus to correct cubitus varus: do both internal rotation and extension deformities need to be corrected?

BACKGROUND

A variety of osteotomies has been proposed to correct posttraumatic cubitus varus deformity as well as any associated hyperextension and/or rotational deformities. However, lateral closing-wedge osteotomy and step-cut osteotomy, both of which have been used extensively with satisfactory outcomes, correct only in the coronal plane. To date, no direct comparison has been made between three-dimensional and simple coronal plane osteotomies.

METHODS

Between 1983 and 2007, we treated eighty-six elbows with a posttraumatic varus deformity. We classified patients who underwent three-dimensional osteotomies as Group I and those who underwent simple coronal plane osteotomies as Group II, and we compared the outcomes between the groups. Clinical evaluation included an assessment of the carrying angle and measurement of the passive range of motion before surgery and at the time of the final follow-up. To evaluate the remodeling capacity of the bone to recover elbow flexion in Group II, we assessed the range of motion before surgery and at the time of the final follow-up in patients who were less than ten years old and those who were more than ten years old.

RESULTS

There was no significant difference between the groups with regard to the carrying angle or the elbow range of motion, either before surgery or at the time of the final follow-up. However, Group I had more significant loss of correction (p = 0.018). In Group II, elbow motion reached the physiological range by the time of the final follow-up in patients who were less than ten years old.

CONCLUSIONS

For osteotomies to correct cubitus varus deformity, correction of internal rotation is not needed. With a three-dimensional osteotomy, it is difficult to maintain correction and to acquire the planned carrying angle because of the small area of bone contact. It is necessary to correct hyperextension in patients older than ten years of age, as after that age bone remodeling is not expected to increase elbow flexion.