PROGNOSTIC FACTORS AFFECTING PATIENT-ORIENTED FUNCTIONAL OUTCOME FOLLOWING SURGICAL TREATMENT OF HUMERAL SHAFT NONUNION

Abstract

Thirty-eight patients with nonunion of the humeral shaft underwent a comprehensive assessment including completion of three patient-based functional outcome surveys as well as the determination of the Constant shoulder and Mayo elbow scores. Treatment consisted of compression plating with or without bone grafting. Smokers were found to have significantly longer time to union as compared to nonsmokers (25.1 weeks vs. 16.2 weeks, p< 0.001). Our results also demonstrated that increased time to union had a significant negative effect on the patient-reported functional outcome scores.

To evaluate the functional outcome and identify prognostic factors that influence the healing time of surgically treated humeral shaft nonunions.

Time to consolidation of operatively treated humeral shaft nonunions was significantly longer in smokers versus non-smokers. Time to union was negatively associated with the patient-reported functional outcome scores.

The long-term functional outcome following surgical treatment of humeral shaft nonunions is dependent upon the time to consolidation. Smoking is a significant remediable risk factor for delayed union following surgical repair of humeral shaft nonunion.

We identified thirty-eight patients (mean age fifty-five years) treated surgically for nonunion of the humeral shaft at a mean follow-up of sixty months. All patients underwent a comprehensive assessment including the completion of the SF-36, the DASH, the SMFA and the determination of the Constant shoulder and Mayo elbow scores. Seventeen (44.7%) patients were classified as ‘smokers’ and twenty-one (55.3%) were ‘non-smokers’. All nonunions united with a mean time of 16.2 weeks for non-smokers and 25.1 weeks for smokers (p< 0.001). Time to union was negatively associated with the Physical Function portion of the SF-36 (p=0.01), the DASH (p=0.01), and the Arm and Hand Function part of the SMFA (p=0.005). The only other factor that had a significant negative effect on the functional outcome scores was the presence of one or more comorbid factors (SF-36, p< 0.001; DASH, p< 0.001; SMFA, p< 0.001). Patient-oriented and surgeon based scores were found to correlate well (range r=0.545 to r=0.916, p< 0.001 for all combinations).