212016May

Understanding Surgery for Cubital Tunnel Syndrome

A number of disorders can cause numbness and tingling in the hand.  When the affected digits are the ring and the small finger, cubital tunnel syndrome is a common cause.  Although many patients improve with conservative treatments, others require surgery.

Overview of Cubital Tunnel Syndrome

The ulnar nerve runs along a groove in the longest bone of an upper arm and behind the elbow.  The ligament on top of it plus the nerve form the cubital tunnel.  Once beyond the elbow, the nerve continues through the forearm and into the hand, where it is responsible for both muscle function and sensation.  Pressure on the ulnar nerve increases when an individual bends the elbow.

Compression of the ulnar nerve can cause numbness and tingling in two fingers and tenderness near the inner elbow, the “funny bone.”  It also creates problems with coordination in the small muscles of the hand, weakness in a hand grip, and lessened pinch strength, according to the Washington University School of Medicine in St. Louis.

A major cause is repetitive activities that put pressure on the nerve.  Other possible causes include a family history or the presence of disorders like rheumatoid arthritis, diabetes, alcoholism, anorexia, hypothyroidism, and obesity.

Surgical Options from a Hand Specialist

The first priority for treating this condition is modifying activity to avoid placing pressure on the ulnar nerve.  Keeping the elbow out of a bent position with splints is one method.  When conservative measures fail, two types of hand surgery are available:

  • Ulnar nerve transposition.  A hand surgeon relocates the ulnar nerve from behind the patient’s elbow to the front of it after freeing it from any adhesions.  Cooper University Health Care reports that it is possible to perform this procedure at either the elbow or at the wrist.  If the nerve is compressed in both locations, the surgeon will work at both sites.  For compression at the elbow, the hand doctor makes an incision and moves the nerve to a new spot in front of the elbow.  The nerve can lie under the skin and fat but above muscle, within muscle, or under muscle, according to each patient’s circumstances.  For compression at the wrist, the incision occurs on the little finger side of the patient’s hand, at the bottom of the palm.  A hand specialist typically performs a transposition on an outpatient basis.
  • Cubital tunnel release is also usually an outpatient procedure.  In this hand surgery, the physician cuts and divides the ligament that forms the top of the cubital tunnel.  Because this increases tunnel size, there is decreased pressure on the ulnar nerve, according to the American Academy of Orthopaedic Surgeons.  New tissue forms across the division as the ligament heals.  The procedure creates added space through which the nerve can slide.  It usually works best with mild to moderate nerve compression.