Technical Tip
Re-stabilizing the Traumatically Unstable Elbow
By Laurence E. Dahners, M.D.
Introduction: Many of us have encountered fracture dislocations that result in extremely
unstable elbows. These often are associated with fractures of the coronoid and the radial head
(the “terrible triad” of elbow instability, coronoid fracture and radial head fracture), but
sometimes follow simple dislocations. Suture of the ligaments provides insufficient strength to
re-stabilize the joint. Sometimes the joint can be held in an acceptably reduced position in
flexion, but immobilization has its own disadvantages and can fail in highly unstable joints.
Recently several authors have published on stabilization of such elbows with hinged external
fixators and have had relatively good results. However, hinged external fixators are very
expensive and can also be quite difficult to apply, especially to apply with sufficient accuracy to
place the hinges correctly at the isometric center of the joint thus allowing range of motion
without subluxation.
Recently I have been stabilizing elbows as shown in the following diagrams and have been very
satisfied with the results. Rather than suture the ligaments (which cannot be done with sufficient
strength to restabilize the joint) I have been placing heavy nonabsorbable suture “from bone to
bone” because such bone-to-bone repairs are much stronger. Subsequently a few tacking sutures
in the ligaments can align them better.
Method: Once the elbow has proven to be unstable so that it cannot be re-stabilized in the
standard fashions I am use the following surgical technique. Preferably this is done through an
extensile posterior incision raising subcutaneous flaps to the epicondyles on either side. The
stability of the elbow is then evaluated. In patients with the “terrible triad” the instability is
almost always for the elbow to dislocate posteriorly because of incompetence of the posterior
bundles of the collateral ligaments, however, the anteriorly directed ligaments are often intact.
Initial inspection may make it appear that the
ligaments are not disrupted as they may be covered by filmy tissue that obscures their disruption,
but probing will show their incompetence. The ulnar nerve must be transposed anteriorly or the
stabilization sutures will impinge on it. Inspecting the joint from laterally a 5mm corkscrew
suture anchor with two, #2 fiberwire sutures is placed at the apparent isometric center of the joint
(centering it in the circle made by the capitellum). In the usual situation of posterior instability, if
you err, you would like to err by placing the anchor slightly distal and perhaps slightly anterior to
the isometric center of the humerus. This will make the stabilization sutures tightest when the
elbow is in extension and most unstable. On the medial side a similar process is used to place an
anchor at the isometric center of the joint. This isometric center will fall within the epicondyle
and so I place it up near the tip of the epicondyle. This allows the stabilization suture to be up
over the actual medial ligaments (so that it does not disturb them during ROM). Please recognize
that this procedure is different from “reconstruction” of the chronically unstable elbow with
medial tendon grafts which are drilled into the base of the epicondyle (the epicondyle often must
be rongeured away to allow correct siting of the tendon graft), instead we are temporarily
restabilizing the elbow with these bone-to-bone sutures while we wait for the disrupted ligaments
to heal. Then I drill a medial to lateral hole through the olecranon as shown in the lateral
diagram. One tail of the fiberwire suture is
passed through the olecranon hole with a Hewson suture passer and the other tail through the
triceps behind the olecranon and they are tied with the elbow at about 90 degrees flexion. Sutures
from the lateral epicondyle are pulled through the holes and tied on the medial side of the ulna
and sutures from the medial epicondyle are pulled through the holes and tied on the lateral side
of the ulna. Before tying them it is extremely important that the joint be completely reduced by
whatever means, even holding it with a K wire if necessary. Small absorbable sutures may be
used to reapproximate and realign any of the ligaments which are not already laying in contact.
Other injuries to the (coronoid and radial head) are treated as appropriate (and often should be
addressed before stabilizing the elbow as there is better access when it is unstable). I have been
starting patients on immediate motion postoperatively using only a sling for protection between
ROM activities and have been extremely pleased so far with the stability this technique
produces. Although we have insufficient followup to qualify for publications this has been very
gratifying in the degree of stability provided in the operating room as can be seen in the videos.