- Isolated Division of the Aponeurosis:
- involves division of aponeurosis between the humeral and ulnar origins of the FCU;
- theoretical disadvantages:
- in addition to decreases in the cross sectional area of the cubital tunnel which occur w/ flexion, there is also a decrease in the mean cross sectional
anatomy of the ulnar nerve (about 35-40%) w/ elbow flexion;
- this indicates that elbow flexion increases traction on the ulnar nerve, which is independent of any extrinsic traction;
- therefore, decompression of the cubital tunnel will not alter traction on the ulnar nerve which occurs with elbow flexion;
- in the study by Dellon et al (1989), only 33% of patients who underwent isolated cubital tunnel release achieved an excellent result;
- references:
- Review of treatment results for ulnar nerve entrapment at the elbow.
- Changes in interstitial pressure and cross-sectional area of the cubital tunnel and of the ulnar nerve with flexion of the elbow. An experimental study in human cadavera.
- Indications:
- limit this procedure to patients whose symptoms seem to arise from compression over the FCU aponeurosis;
- a positive Tinel's sign over the cubital tunnel is a supporative finding;
- Relative Contra-indications:
- ulnar nerve subluxation;
- about 10 percent of the population is prone to subluxation of the ulnar nerve w/ elbow flexion beyond 90 deg;
- these patients would be expected to experience symptomatic subluxation of the ulnar nerve postoperatively;
- likewise, the intraoperative finding of ulnar nerve subluxation following release is an indication that a transposition procedure is necessary;
- osteophytes surrounding cubital tunnel;
- rheumatiod arthritis;
- Anatomy & Sites of Compression
- Technique:
- incision:
- longitudinal incision 8 cm in length;
- attempt to identify the medial antebrachial cutaneous nerve; (may be found crossing the FCU);
- ulnar nerve is identified and tagged in the proximal portion of the incision;
- aponeurosis of the cubital tunnel and the aponeurosis of FCU is incised;
- nerve is then examined for evidence of gross deformation (c/w entrapment underneath FCU aponeurosis);
- if no abnormality is found, then consider submuscular or subcutaneous transposition;
- following decompression it is important to check the effect of flexion on the nerve;
- elbow flexion may reveal excessive ulnar nerve tension;
- ulnar nerve subluxation may be found following cubital tunnel release, in which case a subcutaneous transposition is indicated;
- another consideration would be epicondylectomy
Compression neuritis of the ulnar nerve treated with simple decompression.
Ulnar neuropathy at the elbow: comparison of simple decompression and anterior transposition.
Ulnar nerve decompression at the cubital tunnel.
Review of treatment results for ulnar nerve entrapment at the elbow.