Background: Treatment of distal intra-articular humerus fractures is still a technical challenge. Until now, little is known about the regain of strength and elbow agility after surgical treatment of these fractures. Due to small collectives there is only limited data.
Objective: Investigation of regained strength and elbow agility in patients with intra-articular distal humerus fractures.
Methods: A total of 28 patients were treated with distal intra-articular humerus fractures followed up for an average period of 62.3 months. The following parameters were examined: Arthrosis, heterotopic ossification, functional outcome (MEPS, DASH score, LES) and isometric strength of the elbow in extension and flexion was tested in 30∘, 60∘ and 90∘ in a custom-made positioning device.
Results: There was a high complication rate with 32%. At the 60th month post injury, range of motion (ROM) of the elbow was 114∘ with a reduction of 32∘ compared to the contralateral uninjured side (p< 0.001). The highest reduction was seen in extension with an average loss of 16∘ (p< 0.001). Loss of motion correlated with the fracture severity regarding the AO-classification (r= 0.54, p< 0.01). The average regained muscle force was 81.5% in flexion and 92% in extension in comparison to the contralateral healthy side. Patients over 60 years had less range of motion and inferior results in the DASH score compared to younger patients.
Conclusions: Functional impairment in terms of reduced ROM and muscle force is a common complication after distal intra-articular humerus fracture. Patients over 60 years have a higher deficit of motion in the injured elbow joint and an inferior clinical outcome. Superiority of modern angle-stable implants could yet not be shown.
Keywords: Distal intra-articular humerus fracture; angle-stable implants; loss of muscle force; reduction of elbow agility.