Advancing Shoulder Instability Treatments with Arthroscopic Repairs

Introduction to Shoulder Instability

The shoulder is one of the most complex joints in the human body with multiple planes of motion. Shoulder motion is critical for activities of daily living and participation in sports, allowing us to maneuver our arms in space. The focus of this blog post is on shoulder instability, one of the many conditions that can affect the shoulder joint and limit your ability to use your shoulder in a safe and effective way. In order to understand shoulder instability, it is helpful to review the normal anatomy of the shoulder.

The glenohumeral joint is the technical term for the ball-and-socket portion of the shoulder. The socket, or glenoid, has multiple glenohumeral ligaments that surround it, and a fibrocartilage ring surrounding the rim of the socket called the labrum that serves as a bumper. There are also multiple muscles and tendons that surround the glenohumeral joint and contribute to its stability. When one or some of these structures are injured, it can lead to shoulder instability, during which the ball (humeral head) becomes dislocated from the socket (glenoid). Often, the direction of instability is anterior, although it can be posterior or even multidirectional. The glenoid labrum is commonly injured and there can be varying degrees of bone loss on the ball or socket side. Shoulder instability can be traumatic, as a result of a sports injury, which is the most common form. It can also be associated with baseline ligamentous laxity. Shoulder instability makes up between 4-8% of athletic injuries. It is less common in adults.

What are the Ways Shoulder Instability Has Traditionally Been Addressed?

Not all shoulder instability requires surgical treatment. With the exception of high-risk young athletes, the first line treatment for shoulder instability is often physical therapy. There are also braces used to restrict the shoulder from going into high-risk positions, such as abduction and external rotation in the case of anterior instability.

When nonoperative treatment does not resolve symptoms, there is recurrent instability, or the patient is a high-risk athlete, the physician may recommend surgical treatment for shoulder instability. Prior to the advent of arthroscopic surgery, shoulder instability was treated with open surgery, meaning a relatively large incision and dissection of the tissue to get to the shoulder joint. This would often require taking down and repairing or navigating the muscles and tendons overlying the shoulder joint during the approach and closure. There is still a role for open surgery in shoulder instability, particularly when managing recurrent instability with bone loss, but for most shoulder instability, there has been a trend towards minimally invasive arthroscopic shoulder surgery to treat this condition. The advantage of this type of surgery is that we can perform it through very small incisions and use a camera to visualize the structures within the joint. This allows us to better preserve the structures outside of the joint and produce small cosmetically appealing scars.

What are Recent Innovations in Arthroscopic Shoulder Instability Surgery?

Arthroscopic shoulder surgery in the United States really began in the 1980s, although, it took many years before physicians were able to master this new technique and begin publishing on arthroscopically assisted shoulder surgery (such as Bankart repairs for shoulder instability and rotator cuff repairs for rotator cuff injuries). Since the original adoption of arthroscopic shoulder surgery, there has been an exponential growth in techniques and implants to assist with these surgeries. Some advantages to this approach were quickly noticed by surgeons, including the lower risk of infection. We also began to transition these cases into an outpatient setting, allowing the patient to return home on the day of surgery, just hours after the procedure.

Arthroscopic shoulder instability care has been improved by the innovation of the suture anchor, a device that allows us to gain fixation into bone. Once the device is anchored into the bone, we can use the sutures that come out of that fixation to repair soft tissue. Traditionally, surgeons pass these sutures through tissue and then tie knots to hold the tension on said tissue. With recent innovation there are now knotless mechanisms that afford the same tension without the need for tying knots. This can be useful in areas where a surgeon may want to avoid a stack of knots, such as on the articular surface. We can also use these same anchors to pull portions of the shoulder capsule onto the glenoid (socket), which allows us to tighten the shoulder in a patient with a patulous capsular space.

Another recent innovation in arthroscopic treatment of shoulder instability is the remplissage procedure. This is done to help fill a defect in the humeral head caused by shoulder instability, often called a Hill-Sachs Lesion. During this procedure, a portion of the posterior rotator cuff tendon will be arthroscopically sutured to the humeral head to occupy the defect. This prevents that area of bone loss from engaging with the glenoid and in turn reduces recurrent shoulder instability.

Finally, not only have implants and techniques evolved, but also imaging. The use of 3D imaging such as 3D CT scans has revolutionized the treatment of this condition. These imaging studies allow the surgeon to really assess the condition of the shoulder and perform patient-specific preoperative planning.

Who is the Ideal Candidate?

Patients with recurrent instability, clinical and imaging diagnosis of labral tears, those who have failed non-operative treatment, high risk athletes with an increased likelihood of recurrence, and symptomatic overhead athletes are all good candidates for shoulder instability surgery.

What is the Typical Recovery Process?

The post-operative recovery protocol can vary by surgeon, but often a patient will be asked to use a sling after surgery for a period of immobilization, allowing the repaired structures to heal. This will be followed by restoration of shoulder range of motion with the guidance of a skilled physical therapist. Following this, the patient will begin working on strengthening and finally return to sport activities. Working with a skilled physical therapist during this process is extremely important for an optimized recovery.

Conclusion

In summary, arthroscopic shoulder instability care has progressed with the use of modern anchors and techniques supported by advanced imaging and improved rehabilitation. These advances deliver durable stability and quicker recovery, with ongoing work continuing to advance this field. If you have been dealing with shoulder instability or other shoulder condition, we encourage you to schedule a consultation with a Rothman specialist to explore personalized treatment options. Please visit our appointments page for more details.

This article was co-written by Dr. Nathan Benner, Sports Medicine Fellow at Rothman Orthopaedics.

References

Adam JR, Nanjayan SKT, Monga P. Management of rotator cuff tears - Key historical landmarks. J Clin Orthop Trauma. 2021 Apr 7;18:6-12. doi: 10.1016/j.jcot.2021.03.019. PMID: 33954084; PMCID: PMC8080522.

Villarreal-Espinosa, J.B., Kay, J. & Ramappa, A.J. (2024) Arthroscopic Bankart with remplissage results in lower rates of recurrent instability with similar range of motion compared to isolated arthroscopic Bankart for anterior glenohumeral instability: a systematic review and meta-analysis. Knee Surgery, Sports Traumatology, Arthroscopy, 32, 243–256. https://doi.org/10.1002/ksa.12054