Primary (Nerve) Surgery

The timing and choice of surgical procedure remains controversial.  The number of nerves injured and the extent of their injury will dictate necessity and timing of primary surgery.  Severe injuries that involve the total or global plexus require earlier surgery than injuries isolated to the upper and middle trunks (C5, C6, and C7).  Severe injuries without substantial recovery by 3 months of age require primary surgery by 6 months of age.  Regarding lesions to the upper and middle trunks, although there are several schools of thought, most specialists will agree that if there is no contraction of the biceps muscle by 5-6 months of age, primary surgery is recommended.  Primary surgery is most successful between 3 and 6 months of age.

There is a “window” for primary surgery.  Muscles degenerate and atrophy without nerve supply.  Irreversible degeneration occurs between 18 and 24 months of age.  In addition, nerve regeneration after surgery is slow, it occurs at about 1mm/day or 1 inch/month.  Therefore, primary surgery must be performed with adequate time for subsequent nerve regeneration to reach the muscle and to prevent irreversible degeneration.  Primary surgery is generally not recommended after the child turns 1 year old.    

Primary surgery aims to improve the function of the nerves by utilizing one or more of the following methods: 

1. Neurolysis – clearing away scar tissue that may have built up around the nerve
2. Nerve Graft – the neuroma is removed and a gap is created.  The sural nerve is removed from the calf of one or both legs. The sural nerve is spliced between the gap to reconstruct the injured nerve segment(s).
3. Nerve Transfers – a piece of functioning nerve is transferred to the damaged nerve in order to restore function to the targeted muscle

Secondary Surgery

Secondary surgery is often considered or recommended for the child whose recovery is less than full.  Although this child may have experienced sufficient enough recovery to avoid primary surgery, lack of complete recovery, muscle imbalances and muscle contractures may have resulted in limited motion or bone and joint malformations.  Some of the issues these surgeries may address are the inability of the child to actively externally rotate, reach his hand over his head, turn his palm up, or extend his wrist.  There are several different surgical methods to address these issues. 

Secondary surgeries consist of the following methods:

1.      Tendon transfer – tendon transected, transferred into another tendon or bone, innervation and vascular supply to donor muscle preserved

2.      Joint reduction- most commonly involves the shoulder as muscle imbalance results in contracture and joint shifts out of position. Reduction can be accomplished via open surgery or arthroscopy (ACR- anterior capsular release)

3.      Free muscle transfer – entire muscle-tendon unit transferred with nerve repair and vascular reconstruction

4.      Osteotomy- bone is cut and position changed to augment function

         With most secondary surgeries, the child will sacrifice some small amount of function in order to gain what motion is desired.  As a parent, you must evaluate the pros and cons of each secondary surgery and consider the functional gains against the surgical risks and potential loss of motion.  What is best for your child should be discussed with your doctor.  Second and third opinions should always be considered.