- Discussion:
- motivation: w/ maximal elbow flexion, high extraneural pressures occur at the medial epicondyle;
- hence the medial epicondyle is a major impinging structure which forces the ulnar nerve to make a sharp turn whenever the elbow is maximally flexed;
- medial epicondylectomy allows some anterior displacement of the ulnar nerve and removes the epicondyle as the as an impinging structure during flexion;
- advantages:
- avoids nerve devascularization;
- avoids iatrogenic compression of the nerve which can occur w/ transposition;
- relieves compression of the nerve which occurs in flexion, by removing one origin of the FCU;
- nerve is allowed to seek its own path of least resistance;
- preserves small proximal nerve branches to the elbow joint;
- blood supply to the nerve is preserved;
- disadvantages:
- potential weakness and elbow instability due to iatrogenic injury to the flexor-pronator origin and MCL, respectively;
- protective prominence of the epicondyle is lost;
- postoperative tenderness at the osteotomy site;
- outcomes:
- in the study by Amako M et al, the authors compared minimal medial epicondylectomy (18 patients) for cubital tunnel syndrome w/
decompression of cubital tunnel and preservation of the anterior medial collateral ligament and partial medial epicondylectomy (14 patients);
- both groups had significant improvement in their Yasutake scores following medial epicondylectomy;
- there was no significant difference in improvement of either the Yasutake scores or the motor conduction velocity between the 2 groups;
- valgus instability of the elbow was significantly greater in the partial epicondylectomy group;
- the authors concluded that minimal medial epicondylectomy combined with ulnar nerve decompression is an effective treatment
for cubital tunnel syndrome and that a larger excision of the medial epicondyle should be avoided;
- Comparison between partial and minimal medial epicondylectomy combined with decompression for the treatment of cubital tunnel syndrome
- Anatomy & Sites of Compression
- Technique:
- includes exploration of the ulnar nerve proximally & distally relieving medial ntermuscular septum and releasing arcade of Struthers and the aponeurosis between
humeral and ulnar origins of the FCU;
- skin incision:
- gentle curved incision just anterior to the medial epicondyle;
- look for posterior branches of the medial antebrachial nerve, which tend to cross just proximal to the epicondyle;
- deep exposure:
- identify the ulnar nerve proximal to the epicondyle and tag it;
- origin of the flexor pronator mass is identified over medial epicondyle;
- identification of proximal and distal compression:
- see: anatomy and sites of compression;
- osteotomy:
- ensure that the ulnar nerve is retracted out of the way prior to performing the osteotomy;
- flex the elbow to 90 deg;
- longitudinally incise thru the flexor pronator origin, directly over the center of the epicondyle;
- incise directly down to bone and subperiosteally elevate the origin on both sides of the epicondyle;
- once the epicondyle is exposed, mark the proposed osteotomy site with cautery;
- common mistake is to perform an inadequate bone resection, usually atleast 6-7 mm of resection is needed;
- the osteotomy should be made parallel to the course of the nerve w/ the elbow flexed;
- it is advantagous to include a portion of the supracondylar ridge, inorder to ensure that the attached medial intermuscular septum is also decompressed;
- overly aggressive resection of the epicondyle, however, may disrupt the anterior fibers of the MCL;
- use a rongeur to remove sharp edges of the osteotomy;
- once the osteotomy is completed, flex and extend the elbow to observe free anterior translation of the ulnar nerve;
- following closure, both leaves of the flexor pronator origin are closed;
- Post Operative Care:
- in the study by Seradge 1997, the effects of early and late mobilization following medial epicondylectomy was evaluated in a
randomized prospective study;
- flexion contracture of more than 5 deg was seen in 5% of the early mobilization group vs 52% of the late group;
- patients with flexion contractures had more pain than those without contractures;
- patients in the early ROM group returned to work earlier than the late group;
- reference
- Cubital tunnel release and medial epicondylectomy: effect of timing of mobilization
Medial epicondylectomy for subluxing ulnar nerve.
Cubital tunnel syndrome. Treatment by medial epicondylectomy.
Medial Epicondylectomy for the Treatment of Ulnar Nerve Compression at the Elbow.
Medial epicondylectomy for ulnar nerve compression syndrome at the elbow.
Cubital tunnel release with medial epicondylectomy factors influencing the outcome.
A modified surgical procedure for cubital tunnel syndrome: partial medial epicondylectomy.
Cubital tunnel release and medial epicondylectomy: effect of timing of mobilization.
Minimal Epicondylectomy Improves Neurologic Deficits in Moderate to Severe Cubital Tunnel Syndrome