The authors say this is the first clinical study of the results of surgery for repair of a biceps tendon rupture allowing early elbow motion. Why is that so important? Most rehab protocols require a week or more of immobilization before allowing a gradual increase in active motion. The thinking behind the conservative approach is that the body needs time to allow tendon ingrowth into the bone. Too much stress too soon could disrupt the surgical site.
But surgeons have noticed that patients who don’t follow their instructions and return to aggressive activities earlier than they should, seem to do just fine. In fact, no matter how the injury is treated in the postoperative rehab program, everyone seems to have the same results. And rerupture is rare.
So, what if they protect the repaired tendon for one or two days and then start moving it? That’s the approach two surgeons at the Mayo Clinic in Rochester, Minnesota took with 21 (male) patients. Everyone in the study had a complete acute distal biceps rupture. Distal means the biceps tendon pulled away from the bone where it inserts at the radius (forearm or elbow) bone. Rupture at the opposite end (up at the shoulder) would be considered a proximal rupture. Acute for this study meant the injury happened within the last six weeks before surgery.
The surgical repair done was a 2-incision suture repair reattaching the retracted biceps tendon with transosseous sutures. Transosseous means through the bone, specifically the radial tuberosity. The radial tuberosity is a bump on the radius where the distal end of the biceps normally attaches.
Since the surgeon can’t just glue the tendon back where it belongs, the end of the tendon is attached to a suture, the needle is pushed through the radius, and out the skin on the other side. The suture is then tied over a button outside the skin. Transosseous sutures have been shown to be stronger than suture anchors. Using this type of suture allows for more aggressive early motion and an early return to full motion.
In this study, patients discontinued using the sling after the second day and started moving the elbow and forearm. They were allowed to actively flex and extend the elbow as far as they could comfortably. They were instructed to try and regain as much flexion as possible. Forearm rotations (supination/palm up and pronation/palm down) were restricted to passive range of motion at first. They gradually progressed to active movement.
There was a one-pound weight restriction (i.e., don’t lift or pick anything up that weighs more than 16 ounces or one pound). Otherwise, daily activities were only limited according to what the patient could tolerate or felt comfortable doing. After six weeks, they were allowed to lift two-pounds with a gradual increase in weight lifted. By the end of three months, full strength was expected with unrestricted lifting.
Everyone was followed for at least two years. Some patients were seen for as long as seven years. Results were measured using range-of-motion, strength, and function. Strength was tested in various ways — with the elbow in 90 degrees of flexion and neutral forearm rotation, using isometric muscle contractions, and using isotonic contractions.
The surgeon also checked for biceps integrity using a special clinical test called the hook test. This test is done with the patient’s forearm in supination (palm up) and the elbow flexed 90-degrees. The examiner tries to hook his or her index finger under the biceps tendon from the lateral side (out side of the elbow, away from the body). With an abnormal hook test (indicating distal avulsion of the biceps tendon), there is no cord-like structure under which the examiner may hook a finger.
The patients were also asked to rate the success of the surgery. It was a satisfactory result if the elbow was better than before surgery and/or if they would have the same surgery again. Everyone was satisfied with the results and returned to work with no problems. Some patients were white-collar workers with desk jobs. Most were employed in jobs requiring heavy use of their arms. More than half were involved in sports before the injury.
Full strength was regained in elbow flexion but not forearm supination. It didn’t seem to matter whether the involved arm was the dominant or nondominant hand. Supination strength was affected equally in either case.
One of the variables the authors discussed in this article involved the one-incision versus the two-incision approach to this surgery. Although their study did not include or compare the one-incision method, they noted that there are no real guidelines for rehab and recovery after each procedure.
Most of the time, there is a long period of immobilization (up to six weeks). Concern that the elbow will get stiff without enough movement is one reason surgeons are looking at the effect of introducing movement early on after surgery. The use of immediate active motion in this study is considered fairly aggressive. But patients did well regaining motion and strength without losing function, rerupturing the healing tendon, or gaining a stiff elbow.
The inability to restore full strength in supination remains a mystery. Several theories have been put forth based on altered biomechanics of the repaired tendon, but nothing has been proven yet. For now, it looks like this modified mini-2 incision distal biceps repair is maintained even with early elbow range of motion. Patients like it because they can get back to their regular activities faster with less inconvenience from an immobilized arm.