An ulnar claw is the result of extreme trauma or damage to the ulnar nerve, which runs from the shoulder to the hand. For the thumb and first half of the hand, the median nerve is responsible for movement and sensation; the ulnar nerve is in charge of the final few fingers. As the injury goes untreated, the ring and pinky fingers will become difficult to extend, giving the hand the appearance of a primitive claw.
Damage can occur to the ulnar nerve in a variety of ways. According to the New York Times' online Health Guide, this claw and associated palsy is an extreme result of peripheral neuropathy. This is damage to the ulnar nerve from injury or even from subtle causes like habitually leaning on the elbows or flat on the palms. In this location of the arm, the ulnar nerve is particularly exposed to long-term wear and tear. These slow-developing latter causes are more likely to reveal themselves not with an ulnar claw, but with numb, weak and tingly fingers.
In infants, this damage may be the result of Klumpke paralysis. Also known as brachial palsy, this condition is caused by injury to the brachial plexus shoulder nerves during or after birth. This will reveal itself in not just an ulnar claw, but in complete inactivity of a hand or even the whole arm. The claw may or may not be among the symptoms though, as the arm and hand are just as likely to be completely limp as they are to be unnaturally contracting.
In most cases, doctors will take a multifaceted approach to treating an ulnar claw. Steroid injections and pain medication may relieve inflammation in the short term. A splint might contain the injury causing the nerve damage. Surgical intervention also may be part of the treatment, to remove the cause of the injury and even to repair the damaged nerve. With or without surgery, physical therapy may also be part of the response.
Surgical intervention is perhaps the only way to relieve the symptoms of another condition, called Dupuytren’s contracture, which might reveal itself in an ulnar claw. This rare formation of tissue in the palm restricts nerve activity and eventually the proper use of the fingers. According to the U.S. National Institutes of Health, this condition most often strikes smokers, alcoholics and those with diabetes. As the palm-side growth takes up more and more space, the apparent claw will become more pronounced and the fingers more painful to fully extend.
