Case Study - Ulnar Nerve Palsy

June 2020

The ulnar nerve is one of the 3 large nerves that extend from the neck down to the hand - along with the median nerve and radial nerve. If the ulnar nerve is injured the patient usually describes a typical pattern of tingling or numbness - worst in the little and ring fingers. Think of what happens if you bump your 'funny bone'. When that happens, you are actually bumping your ulnar nerve, and you tend to feel it in your little finger.

This 60yo woman spontaneously developed an ulnar nerve palsy several months ago. First she noticed some tingling in the fingers, and then her little, ring and middle fingers started to 'claw'. The exact cause of her nerve palsy was never identified, but may be related to her long history of diabetes.

In the picture showing her clawed fingers, she is trying as hard as she can to straighten her fingers. Unfortunately, the ulnar nerve palsy causes weakness of certain small hand muscles (called lumbricals). which means that the harder she tries to straighten, the worse the clawing becomes. Over many months of persistent clawing her knuckles have become very stiff, and now even with help she can't straighten her fingers.

We have fitted her with a custom-made thermoplasdtic splint called a static-progressive splint. Each stiff finger has its own little sling which is pulled up by the fishing line, through the outrigger, and back to some velcro so she can control the tension herself. She will apply gentle tension to each finger, and will try to build up her tolerance until she can wear the splint for several hours a day.

No amount of extra knuckle flexibility is going to make her ulnar nerve function better. But hopefully we can help her hand to be much looser, easier to manage, and more comfortable.