Underreduced supracondylar fracture of the humerus in children: clinical significance at skeletal maturity.

BACKGROUND

Although supracondylar fractures of the humerus in children are common, the literature is sparse regarding acceptable limits of reduction of these fractures in the sagittal plane.

METHODS

We retrospectively reviewed 223 pediatric cases of supracondylar fractures of the elbow treated in our hospital between the years 1996 and 2000.

RESULTS

In 30 patients, we found some degree of underreduction of the extension component of the fracture. Twenty-two of them were followed and evaluated at or close to skeletal maturity. The mean age at the time of fracture was 5.4 years, the mean follow-up was 8.2 years. Radiographic remodeling, range of elbow motion, and awareness of the patients to the functional limitation were evaluated. At final follow-up, 17 (77%) of the patients had radiographic abnormality of the humerocondylar angle (a difference of 5 degrees or more compared with the uninjured side). Eleven patients (50%) had limited elbow flexion, and 7 (31%) were aware of this deficit. Most of the underreductions occurred when reduction was attempted in the emergency department, when the angulation was not appreciated, and when the cast was applied without any reduction attempt. Patients who were left to heal with some degree of extension developed limited end-elbow flexion and were aware of it. Although only 3 patients felt minor subjective functional disability at the last follow-up, 10 patients had unsatisfactory results according to Flynn criteria for motion restriction.

CONCLUSIONS

The treating surgeon must be aware of this possible outcome and be more demanding in the reduction of the extension component of the fracture. Otherwise, clinically significant limitation in elbow flexion may occur. Although the reduction of moderately displaced fractures may seem simple, it should be performed under general anesthesia and with radiographic control of reduction and pin placement.