Ulnar Nerve Entrapment or Cubital Tunnel Syndrome and Rheumatoid Arthritis

What is Cubital Tunnel Syndrome

Cubital Tunnel Syndrome is a condition where the Ulnar nerve is compressed at the elbow, and no longer moves freely through the cubital tunnel.  The cubital tunnel is formed by muscle, ligament and bone at the elbow, and normally the ulnar nerve passes freely through it and supplies feeling to the little finger and half the ring finger.  It controls the muscle that pulls the thumb into the palm and controls the small muscles of the hand.

When the nerve becomes entrapped or compressed, it causes numbness and painful pins and needles in the hand, particularly the last two fingers.  As the condition progresses, the pain becomes constant and the muscles become affected, causing clumsiness and loss of function.  In severe, long standing cases, the nerves gradually stop working, and the muscles of the hand waste away.

Once cubital Tunnel Syndrome has reached this point, surgery may no longer be successful.  My case is severe, with only the one nerve that supplies my first finger and thumb still working.  I have severe muscle wastage in both hands, and my surgeon estimates I have about 20% of normal hand function and strength.

She is hoping, with surgery and physical therapy I might be able to get up to 60% hand function back, best case. It is possible I will get no improvement at all in function, but I should get pain relief.  That may not sound great, but the surgery is essential, because if I don’t have the surgery, I will lose all function in my hands, and that will be irreversible.

What causes Cubital Tunnel Syndrome

In many cases the cause is unknown. Some people naturally have less space at the cubital tunnel and the nerve is more easily trapped.  In other people the nerve shifts and snaps over the bony point on the inside edge of the elbow (medial epicondyle) which, over time, causes nerve irritation.  Leaning on the elbow often can irritate the nerves and cause numbness and pins and needles.  A direct blow to the elbow can cause damage that results in ulnar nerve entrapment.

In rheumatoid arthritis, if the elbows are affected, the constant inflammation and fluid buildup compress the nerve, and cause the syndrome.  This is the cause in my case.  Constant, active inflammation in my elbows.  Doctors may not be able to see or feel my inflamed joints, but they can certainly see the damage that unchecked disease has been done.

Treatment for Cubital Tunnel Syndrome

Most cases, if diagnosed early, can be treated conservatively with physical therapy, bracing and splinting.

If conservative treatment isn’t successful and symptoms continue, surgery is necessary.

The goal of surgery is to release the pressure on the ulnar nerve as it passes through the cubital tunnel.  There are two surgeries for Cubital Tunnel Syndrome, and which method is appropriate depends on the cause and severity of the condition.

Cubital Tunnel Release/Decompression

Cubital Tunnel Release is appropriate for mild to moderate cases, where the nerve does not slide out from behind the medical epicondyle (bony ridge on the inside of the elbow) when the elbow is bent.

It is the simpler of the surgeries, and recovery time is quicker.  The ligaments that form the top of the cubital tunnel are cut and divided, increasing the size of the cubital tunnel, creating extra space.  The ligaments heal over time, but the extra space remains, which gives the nerve more room to slide through.

Ulnar Nerve Transposition

The other method is called Ulnar Nerve Transposition.  In this surgery, the surgeon forms a completely new tunnel from the flexor muscles of the forearm.  The ulnar nerve is then moved out of the cubital tunnel and placed into the newly created tunnel.  This is a more involved surgery, with a considerably longer recovery time.

Medial Epicondylectomy is another procedure that is sometimes also performed when the nerve has become caught on the medial epicondyle (bony point on the inside of the elbow).  The small piece of bone is simply removed, and then the ulnar nerve can slide through the tunnel more freely.

Surgery Recovery

After surgery, the arm(s) are bandaged and splinted.  With decompression surgery, recovery is faster, and physical therapy can begin sooner, and less therapy is required.

After nerve transposition, active physical therapy starts after 6 weeks, and could continue for three months.  This is because the flexor muscles have to be sewn together to form a new tunnel, so there is significantly more pain and healing time involved.  The elbow will be placed in a splint and wrapped in a bulky dressing and the elbow will be immobilized for three weeks.

Recovery times after surgery also depend on which procedure you have undergone.  The table below is what my surgeon gave me.  I’ll be having the transposition surgery, and can expect the longer recovery times.  The notes also state that the more severe the condition is before surgery, the longer the recovery time will be.  My surgeon told me mine is very severe.  She said hasn’t often seen worse hands than mine (and she was totally gobsmacked that I see a rheumatologist and a neurologist regularly and that neither one picked it up earlier, when I would have had much better odds for success).

The severity of my hands would probably explain why she has given me such long recovery estimates.  I am hoping recovery will be quicker.  But it’s good to expect the worst.

*Some people do not get a full recovery, especially in severe cases.  By this time all the expected improvement will have occurred.

Cubital Tunnel Syndrome can affect one or both arms.  Mine are both severe.  My surgeon is doing by my elbows at once, which she only rarely does.  This is to save me money, and the stress of two surgeries.  She is confident that I’ll manage, so I am too.