Incidence and Functional Outcomes of Malunion of Nonoperatively Treated Humeral Shaft Fractures
We conducted a study to determine the overall incidence and long-term clinical and functional outcomes of patients with malunion after nonoperative management of humeral shaft fractures. Fifteen patients with radiographic malunion (>20° angulation or shortening of ≥2.5 cm) were identified, and their medical records retrospectively reviewed for information about their injuries and treatment. Long-term outcomes were assessed with a self-reported questionnaire, the DASH (Disabilities of the Arm, Shoulder, and Hand) form, and physical examination.
Of 91 study-eligible patients, 15 (16%) had malunion after nonoperative management of humeral shaft fractures treated over an 11.5-year period. The 8 patients reached for long-term follow-up had a mean DASH score of 10.4. Seventy-five percent of patients reported having no functional limitations and being satisfied with the outcome of their treatment. However, 75% also reported a noticeable cosmetic deformity; for 25% of patients, this was a major reason for dissatisfaction.
Our findings suggest that malunion may be more common than previously thought but, for a majority of patients, does not cause significant pain, functional limitations, or dissatisfaction. However, patients should be counseled about the high likelihood of cosmetic deformity, which they may find bothersome.
The major limitation of this study was its small patient population. (Obtaining a larger series of patients with malunion after nonoperative treatment of humeral shaft fractures likely would require a multicenter study.) Some of our study findings, such as lack of correlation between degree of malunion and subsequent functional or subjective outcomes, would require a larger sample size for verification and more definitive conclusions. Another limitation is that the study was not designed to evaluate the cause of malunion. Therefore, we cannot draw any definitive conclusions regarding what may have contributed to the development of malunion in our study population. However, all our malunion patients were compliant with their treatment protocol, and they showed no significant difference in incidence of potential risk factors (eg, obesity, comorbidities) compared with the patients who healed without malunion.
Conclusion
Malunion after nonoperative management of humeral shaft fractures does not appear to result in significant pain, dissatisfaction, or functional limitation as measured on physical examination and with validated objective outcome measures in the majority of patients. Furthermore, no patients in this study required surgical intervention for any residual limitations or complications after malunion. The majority of patients reported a noticeable cosmetic deformity, which left a small subset of patients dissatisfied. Overall, our study findings can be used to help counsel patients before and during nonoperative management—particularly patients who appear to be healing with some malunion. Our findings suggest that operative intervention to prevent malunion is not necessary, as it likely would not result in any overall improvement in patient function or satisfaction, but patients should be counseled regarding the high likelihood of cosmetic deformity, which may or may not be bothersome.
