What is a claw hand?
The claw hand (or claw hand) is the leading symptom of damage to the ulnar nerve (ulnar nerve). The ulnar nerve originates from the brachial plexus, a network of nerves at the level of the cervical spine, and runs downwards in depth on the back of the upper arm. Close to the elbow, the ulnar nerve travels to the forearm and further to the hand.
Many know the unpleasant feeling of bumping into the “funny bone or nerve”. Here, the ulnar nerve is affected and triggers the pain and sensory disturbances in the arm and hand. On the hand, the nerve supplies the small and ring finger as well as the palm and parts of the back of the hand underneath it with sensitive sensation (with tactile sensitivity).
It also controls various muscles of the forearm and hand, which enable hand flexion and finger movement (spreading, bending, etc.). Due to its relatively superficial course at the elbow and forearm, it is particularly often affected by injuries. The nerve-ulnaris paralysis is therefore the most frequently occurring nerve paralysis of the extremities.
Associated symptoms
In addition to the claw hand, depending on the extent of the damage, there may also be sensory disturbances of the hand. These affect the ring and little fingers as well as the adjacent half of the hand on the palm and back of the hand. The higher the damage, the more extensive the losses.
This can include numbness, tingling, temperature sensation disorders, burning or pain. If the paralysis lasts for some time, there is visible muscle atrophy of the hand. The damage to a nerve can be manifested in many ways.
Pain can also occur. Sometimes directly after the damage, sometimes only after some time. These are typically seizure-like and can feel burning, stabbing or dull.
This so-called nerve pain (neuropathic pain) can be extremely stressful. The treatment is different from other types of pain. Antidepressants, drugs against epilepsy (anticonvulsants), opioids, or local anesthetics (lidocaine, capsaicin) are used.
Physiotherapy or occupational therapy are also helpful. The described sensations can manifest themselves in many different ways. Frequently affected persons complain of numbness. Many know this feeling when one has hit one’s elbow and thus the “funny bone or nerve”. This can be accompanied by pain, sensations of temperature loss or the feeling that the arm and hand have “fallen asleep”.