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which would suggest a watchful waiting approach in the Anterior nerve transposition (subcutaneous, intramuscular,
hopes of an eventual late recovery. Among 30 surgical and submuscular) is the most commonly used revision
revisions for the recalcitrant cubical tunnel, Gabel technique after a failed nerve decompression, [14,19] in cases
and Amadio performed surgery in 9 patients who of nerve instability (nerve subluxation or luxation), after
[15]
had normal EMGs, concluding that normal conduction medial epicondylectomy, and following a failed anterior
values were not sufficient to exclude surgical revision. transposition.
Ultrasound (US) examination may also aid surgeons in the Among nerve transpositions, subcutaneous transposition
decision‑making process. In fact, the dynamic and static yields unpredictable results when used in revision surgery,
evaluation of the ulnar nerve may reveal morphological and, for this reason, it is rarely used by surgeons. If
alterations to the nerve trunk and to the surrounding the nerve is moved from the cubital channel to reduce
soft tissues. In the authors’ experience, magnetic mechanical stress, it is transposed to a relatively
resonance imaging (MRI) offers less information than hypovascular area [13,15] where it is more exposed to direct
a well‑performed US. In association with the clinical trauma. Gabel and Amadio noted 12 poor results in
[19]
[15]
evaluation, these 2 diagnostic tools may assist in the 17 cases, whereas Caputo and Watson reported a 50%
[34]
decision‑making process. When surgery is postponed, rate of poor results using this technique.
and symptoms do not improve in a short period, revision
surgery should be reconsidered. In conclusion, in some Intramuscular transposition is rarely used in revision
cases, particularly in those of primary nerve instability, surgery, with only two cases described in the literature,
the pre‑ and postoperative conduction studies may be both of which yielded unsatisfactory results. [15,18]
negative even in the presence of severe neuropathic Submuscular transposition is widely used in revision
symptoms. In these cases, US examination and MRI may surgery. [41‑43] With this technique, good results may be
aid in identifying areas of mechanical nerve injury that achieved following failed simple decompressions, medial
may indicate the need for surgery. epicondylectomy, and failed superficial transpositions. [14‑16]
Indications for revision surgery If performed using the proper technique, the results
of anterior submuscular transposition are superior to
The persistence or worsening of neuropathic pain, a those obtained with other techniques. In contrast,
decrease in cutaneous sensitivity with paresthesias along the if this technique is employed for the treatment of
territory of the ulnar nerve in the hand, and muscle deficits failed submuscular transposition, the results are not
despite conservative medical treatment are indications for satisfactory. In such cases, division of the epitrochlear
[15]
revision surgery, [14,33] especially if they are associated with muscular bridge and superficial transposition of the
significant worsening of the conduction study results.
nerve with associated external neurolysis yields good
Techniques in revision surgery results. [34,44]
The literature [14‑16] regarding surgical revision of failed The following techniques are not effective and are
ulnar nerve decompression at the elbow is limited to a few rarely used: (1) the relocation of the nerve in the cubital
retrospective studies and case reports. [26,29,34] According tunnel has rarely been used by surgeons, as it is an
to these reports, superficial anterior transposition is the ineffective method of treating recalcitrant ulnar nerve
most commonly employed technique for primary surgery compression; [14,22,33] (2) the results of nerve isolation
and presents a failure rate of 60‑80%. [35,36] with synthetic material, such as silicon or polymeric
The goal of revision surgery is essentially to debride substances, are unsatisfactory; [32,41] and (3) wrapping the
the nerve of its surrounding fibrosis that is causing the ulnar nerve with autologous saphenous vein has been
compression and kinking. Neurolysis has an important described with good results. [45,46] Additional studies
role in the revision of failed surgery of the ulnar nerve are needed prior to declaring this technique as an
at the elbow. However, neurolysis cannot be used as an effective method for the treatment of failed ulnar nerve
isolated technique because simple scar excision activates decompression.
a fibrotic reaction that, within a brief time interval, will The authors prefer nerve isolation by means of
compress the nerve again, leading to failure. The removal muscle flaps or fat tissue [16,47] integrated with anterior
[15]
of external perineural fibrosis is the primary indication submuscular transposition in cases of extensive perineural
for neurolysis. [37‑39] When the fibrosis extends within the and soft tissue fibrotic reactions.
nerve, among the fascicles, internal neurolysis should be
considered. However, in such cases, damage to the vascular Technique preferred by the authors
supply of the internal nerve may occur, and severe nerve Anterior deep transposition is the method of choice
scarring may develop, jeopardizing the attainment of a for many surgeons when revision ulnar nerve surgery
good result even in cases of anterior nerve transposition. [15] is necessary. When approaching a revision surgery for
recalcitrant ulnar nerve compression, it can be difficult
Medial epicondylectomy is not considered a satisfactory to locate the area of nerve compromise. For this reason,
choice for revision surgery, as demonstrated by poor a thorough exploration of all of the possible areas of
results in all of the cases treated by Goldberg et al. These compression is necessary, starting from the proximal arcade
[40]
results may be due to the fibrotic and hypovascular tissue of Struthers to the deep septum between the FCU and the
in which the nerve remains following the procedure. [19] flexor‑pronator group. [3,14,15] The skin incision in revision

Plast Aesthet Res || Vol 2 || Issue 4 || Jul 15, 2015 179