Post-traumatic weakness of elbow extension

A man in his 50s presented with a one month history of left elbow weakness without elbow pain.

Five months earlier, he fell while hiking and injured his left elbow—at that point, there was pain and swelling but function was normal. Olecranon bursitis was diagnosed and analgesia was prescribed.

Before this he had normal elbow function despite left olecranon fracture surgery 20 years earlier.

At this presentation, he reported resuming weight training four months after the recent fall but noticed weakness when he extended his elbow during push-ups.

On examination, the old olecranon fracture scar was visible and non-tender swelling was noted at the proximal part of the posterior arm (fig 1 …