Differences in outcome and complications between 2 distinct complex traumatic elbow instability patterns. A retrospective comparison of terrible triad and olecranon fracture dislocations.

BACKGROUND

Terrible triad (TT) of the elbow and olecranon fracture dislocation (OFD) injuries are a combination of 2 different types of unstable fracture dislocation injuries classified under traumatic elbow instability patterns. Despite the differences in injury mechanisms, similarities in the structures disrupted and treatment principles make it meaningful to compare outcomes and complications after surgical treatment of these injuries.

METHODS

We reviewed data of 91 patients who underwent surgical treatment for TT injuries and olecranon fracture dislocations and were assessed for inclusion during the study period between 2012 and 2021. After exclusions, 79 patients (TT: 44; olecranon fracture dislocations: 35) were included for analysis. Elbow and forearm range of motion, joint stability, and other procedure and injury-related complications were assessed and compared at a mean follow-up of 49 ± 18 months. Functional outcome was analyzed using the Mayo Elbow Performance Score (MEPS); Oxford Elbow Score; and the Quick Disabilities of the Arm, Shoulder, and Hand scores.

RESULTS

Patients with TT had significantly better flexion-extension arc (P = .014) and less extension deficit (P < .001) but less supination (P < .001) compared to patients with OFDs. The functional outcome scores, incidence of complications and need for repeat surgeries were similar in both groups except for radiological evidence of elbow arthritis which was more common in the OFD group (P = .03). Eighty-four percent of patients in the TT group and 86% in the OFD group had good to excellent MEPS. Patients without complications also had better MEPS in both groups compared to patients with complications (P < .001).

CONCLUSION

Good-to-excellent functional outcome can be expected in majority of patients with TT and OFDs. Complications are common and can be expected in more than 40% of patients. Secondary surgical interventions may be needed in more than 25% of patients.