This is a cadaveric study using 8 upper extremities to evaluate the efficacy of three different ligamentous reconstructions designed to restore varus and posterolateral rotatory stability to the elbow using the flexor digitorum superficialis tendon. The first technique utilized was a single-strand repair, which created the sling under the radial head by passing from the lateral epicondyle to the crista supinatorus of the ulna. The second technique was one that passed from the lateral epicondyle to the olecranon at the level of the radiocapitellar joint and did not recreate a posterolateral sling for the radial head. The third technique was a double-stranded technique that reconstructed both limbs. The authors tested the upper extremities for varus-valgus laxity and performed a posterolateral shift test on the specimens. Results demonstrated no significant difference between any of the repairs in either the shift test or in maximum varus-valgus laxity.
The significance of the this study lies in the fact that the addition of a reconstruction sling for the radial head to prevent posterolateral subluxation of the radial head does not provide any additional stability provided a constraint to varus-valgus has been restored. From a technical standpoint, the use of the two-drill holes in the ulna, while not necessarily important for stability, certainly allows the passage of the graft through bone. This is probably a stronger construct than, for example, the use of bone anchors for this purpose. For this reason, the double-stranded technique may continue to be a more reliable construct. However, the exact positioning of the holes in the ulna is clearly less important than the ligament origin at the epicondyle.
Related Links
Journal of Shoulder and Elbow Surgery