Anterior Instability Should Be Treated Arthroscopically—Opposes

Without doubt, the introduction of the arthroscope has changed the way orthopedic surgery is practiced and has tremendously benefited our patients. It has offered the opportunity to see “joints in action” and led to the understanding of pathophysiologic processes in ways undreamed of before its use. Furthermore, in the shoulder in particular, the arthroscope has given us a far better understanding of “dynamic anatomy.” Intraarticular structures that were once thought to provide only a static role in joint mechanics are now seen truly in vivo where their dynamic role is much more appreciated and, theoretically, better understood. The complex role and interaction between the glenoid labrum, the glenohumeral ligament complexes and rotator cuff musculature are seen and far better understood as a result of arthroscopic study and investigation.

But, we didn’t stop walking when the car was invented and we didn’t stop driving when the jet was invented. While technological advances are welcomed, we cannot and should not blindly abandon past experiences; we must critique the “new” with an eye to the “past.” History is littered with great ideas that later were seen to be “not so great!” This is not to suggest that the arthroscope is likely to be abandoned as a tool. But, how long ago was asbestos the greatest material invented for use in fireproofing buildings? How long ago was Freon the “wonder gas” that allowed the inventions of the refrigerator and air conditioners? And, more pertinent to health care and orthopedic surgery, how long ago was it that thermal capsulorraphy was the quick and easy answer to managing shoulder instability?

While technology must advance, so must our vigilance. In most cases, medical advancements in technology must be met with a critical review of the results of its application, not only in the short term, but in the long term as well. With now nearly 30 years of use, we certainly understand the role of the arthroscope as a diagnostic instrument, but its therapeutic role seems to grow almost daily—even in 2006. Within the last 2 years alone procedures such as suprascapular nerve release at the suprascapular notch have been proposed; posterior capsular plications, capsular releases for adhesive capsulitis, and implantation of small surface replacement have been introduced. But again, our rate of introduction of new techniques has exceeded our speed of critical review. Our enthusiasm has, in some cases, blurred our objectivity in outcomes. Like most things in life, and even more often in the practice of medicine, there are few, if any absolutes. And that goes for surgery as well. Not all cases can or should be done with only one technique. Certainly not ALL rotator cuff tears can be repaired arthroscopically—notwithstanding what we read in the literature or hear from podiums. And, as I will explain, not ALL shoulder instability can or should be treated with arthroscopic techniques.

In reviewing and debating the point that “anterior instability should be treated arthroscopically” I am reminded of the wisdom and wit of Mark Twain who wrote about, “Lies, damn lies and statistics” as the natural order of interpreting and disseminating data and personal points of view! So it is with the concepts put forth by my colleague in this debate regarding the management of shoulder instability. I would never argue against the very important role the arthroscope plays in some cases of surgical management of this condition. But to suggest that it is the only technique or even the better of the two techniques in treating shoulder instability reminds me of that wisdom of Mr. Twain.

It was George Santayana who noted that unless we are understand the past, we are condemned to repeat it. Therefore, it is critically important that we review the past, both distant and recent—and both with respect to open surgery and arthroscopic surgery—before we come to any conclusions.

Carter Rowe, MD, was arguably the most critical analyzer of shoulder instability during his lifetime. Throughout his career, he devoted his efforts to study and understand the mechanisms of shoulder dislocation and their treatment.1 During his many years as an orthopedic surgeon, he became a prolific writer and he earned the profound respect of his colleagues and peers for his honesty and integrity while studying his patients and their outcomes from his surgical efforts. Few would argue that he set the bar and established the “line” to which we must compare all other treatment regimens in the management of shoulder instability repair.

In a classic article, Rowe and coworkers2 reviewed and analyzed 161 patients with shoulder instability over a 30-year period. Only 1 of 46 patients with a dislocation on their dominant side and 1 of 31 with a dislocation on their nondominant side failed to return to the competitive activities in which they participated before their surgery. Furthermore, 98% of the patients rated their result as excellent or good. At the completion of this very long-term analysis of his results, he concluded that, “early return of motion and function can be expected, and resumption of athletic activities with no limitation of shoulder motion is possible.”2

In light of the successful restoration of stability by means of the open Bankart repair—with a 50-year track record of success—this must be the point of reference by which we measure and critique arthroscopic results.

The bandwagon rolls on: arthroscopic surgery is “hot,” it is “in vogue,” “… all the athletes get it done!” It is “failsafe,” there are “no complications.” And the biggest lies of all: “You heal faster” and you “can return to sport sooner.” Six months following a Bankart repair, the only differences between the arthroscopic technique and the open technique are the length of the incision and the lack of long term follow-up on the arthroscopic technique. The peer-reviewed literature documents the long-term success of the open technique.3 Yet in another published article, authors reviewed 61 patients who had arthroscopic Bankart repairs for their anterior instability.4 Follow-up spanned 2 to 8 years and the authors report a failure rate of 18%. Thirteen percent of patients were dissatisfied and those patients who led active lifestyles with anything but normal glenoid morphology had a recurrence rate of 43%.

Mazzocca and his coworkers5 published data on the results of arthroscopic anterior stabilization in contact athletes. At 2 to 5 year follow-up, 18 collision and contact athletes under age 20 had a 15% recurrence rate. An even greater indictment of arthroscopic Bankart repair was published by Mohtadi and coworkers6 as part of a meta-analysis. These investigators analyzed 18 peer-reviewed articles from the Medline database as part of their analysis. They concluded that “pooled odds ratio for recurrent instability and return to activity were at the 95% confidence that open repair has a more favorable outcome than arthroscopic repair.”

When results of arthroscopic Bankart repair are analyzed in throwing athletes, the same poor results are documented in peer-reviewed literature. Ide and coinvestigators7 performed a prospective study of 55 athletes and reported that 32% of throwing athletes could not return to their sport and 20% of all patients could not return to their preoperative level of activity.

One may ask, “Why are arthroscopic results poorer than open surgery?” There are likely several answers but two explanations likely account for the majority of clinical failures. During the instant of the injury, there is likely a failure of tissue compliance where the capsular tissue is stretched beyond its elastic limit and internal strain is exceeded. In other words, the capsular compliance has been altered. In recognition of this component of the injury, thermal shrinkage was performed—with dismal results.8 Because of a very significant potential of thermal injury to the articular surfaces, this technique was thankfully short lived and, for the most part, abandoned. In its place, arthroscopic capsular plication has been introduced as a way of dealing with the poor tissue compliance (Fig. 1). This technique remains untested and there are no long-term outcomes data to suggest its benefit or support its role in the surgical management of shoulder instability. Open techniques can advance the capsule superiorly and laterally while at the same time hold the limb in a specific position to ensure proper tension in the soft tissue sleeve during the capsular reconstruction (Fig. 2). This likely affords the better opportunity to “reset” the proprioceptive nervous system of the shoulder.

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Figure 1. In addition to grasping the labral tissue, a variable amount of capsular tissue is secured as well. However, it is extremely difficult to determine the correct amount of tissue obtained in arthroscopic techniques and it is easy to excessively tighten the tissue and thus lose external rotation. Furthermore, as the arrow indicates, when the repair is performed intraarticularly, the knot becomes a “foreign body.” Newer knotless anchors may eliminate this problem but the repair remains nonanatomic.

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Figure 2. With open techniques, the Bankart lesion is effectively and anatomically treat by securing the labrum extraarticularly. The capsular redundancy can be addressed by advancing it laterally and superiorly simultaneously while controlling and reproducing the proper degree of external rotation.

The other explanation for higher failure rates with arthroscopic Bankart repairs lies in the fact that the repair is nonanatomic! Few would argue that surgeons are better engineers than “Mother Nature.” With open techniques, the surgeon can reconstruct the normal anatomic relationship between the capsule and the labrum (Fig. 3). In the normal state, the capsuloligmentous structures are contiguous with the labrum. Using present state-of-the-art techniques with anchors of various designs, the capsular tissue cannot be made contiguous with the labral tissue and results in a soft tissue sulcus (Fig. 4). While this technique may impart adequate stability for patients will lesser demands, it likely accounts in part for the higher failure rates in high demand contact and throwing athletes.

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Figure 3. The thin arrow shows the normal contiguous capsulolabral anatomy. Arthroscopic techniques that are performed intraarticularly necessarily leave a “pouch” where the anchoring device is placed. There is not a continuum of cartilage to labrum to capsule.

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Figure 4. This anatomic specimen demonstrates the early days of arthroscopic instability repair. But it does indicate the fact that any intraarticular repair does not establish the capsulolabral continuum of the normal shoulder. Open techniques with their extraarticular capsulolabral repair more closely resemble normal anatomy.

In this debate, we are confined to reviewing past experience and present technology. It is possible, if not likely, with time, technology, and the innovative spirit, advances will be made such that results of arthroscopic techniques of repair may surpass those of open techniques. But we cannot and should not expose our patients to unproven procedures, or worse—procedures that have demonstrated themselves to be inferior—to other known techniques. In today’s reality, open instability repair provides predictably superior outcomes compared with arthroscopic procedures.