Shoulder arthroscopy is a minimally invasive technique that allows orthopaedic surgeons to assess-and in some cases, treat-a range of conditions affecting the shoulder joint. During the procedure, the orthopaedic surgeon makes small incisions or portals in the affected joint, and then inserts a tiny camera lens and fiber optics to light the interior space. Pictures obtained with the camera are then projected onto a screen in the operating suite.
The use of the arthroscope to repair injuries to the shoulder has rapidly increased over the past 5 years. Today surgeons are typically utilizing the arthroscope to assist in the diagnosis and repair of impingement syndrome, as well as rotator cuff and labrum tears. Rotator cuff tears are tears to the tendons in the shoulder, usually caused by trauma to the area or through gradual degeneration from pressure and friction caused by the overlying acromium process. Arthroscopic surgery is used to open up the acromion space, which takes pressure off the torn tendon. The damaged tendon, however, is not repaired in this case. Impingement syndrome, on the other hand, is caused by the irritation of the tendons and/or bursa in the shoulder. In this case, arthroscopic surgery is used to remove acromial spurs, which cause the pain. If ligament laxity is the cause of the impingement syndrome, arthroscopic surgery can be used to correct the problem, as well. The advantages to doing shoulder arthroscopically are Less pain and overall shorter recovery time.
Birth of Arthroscopic Shoulder Surgery
Early use of arthroscopy focused on the knee, it might come as a surprise that the first arthroscopic evaluation of a knee actually took place in 1918. (This involved the insertion of the scope into a joint, without the benefit of additional lighting.) Additional efforts were made during the following decades, but it was not until surgeons were able to obtain adequate lighting with fiber optic technology (in the 1970s and 1980s), that arthroscopy became truly useful. Instruments and techniques that yielded good results in the knee were adapted by orthopaedic surgeons who specialized in the shoulder some seven or eight years later.
Anatomy of the Shoulder
While many people Think of the shoulder as a single joint, it is actually made up of two joints: the acromioclavicular joint, where the acromion of the shoulder blade and the collarbone (clavicle) meet, and the gleno-humeral joint, where the head of the humerus (the upper bone in the arm) meets the glenoid, the cup-like portion of the scapula. There is also potential space (the subacromial space) between the acromion and rotator cuff tendon. Injuries to the shoulder may occur in either joint or in the soft tissues that support and stabilize it.
Arthroscopic Versus Open Shoulder Repair
The diagnostic use of shoulder arthroscopy provides the surgeon with multiple views of the joints as well as greater access to small spaces inside the joint. Compared with the open incisions formerly needed to assess and treat some conditions, there is less damage to soft tissues, and a more rapid recovery. Diagnostic arthroscopy is performed under general anesthesia. Interestingly, use of arthroscopy to diagnose problems of the shoulder has also revealed previously undiscovered lesions that were not detectable during open surgery. The SLAP (Superior Labrum Anterior Posterior) lesion, which affects the labrum, a rim of cartilage that surrounds the glenoid, was detected in the mid-1980s during arthroscopic evaluations. (This painful condition can also be treated arthroscopically.) As with diagnostic evaluations, therapeutic applications of arthroscopy can obviate the need for large incisions. Early treatment attempts focused on repairs of the labrum. Labral tears are just one injury that contribute to shoulder instability, a condition that can lead to subluxation (partial dislocation) or dislocation of the shoulder.
Arthroscopic Rotator Cuff Repair
In the early 1990s, orthopedics surgeons began employing the arthorscopic technique for repair of tears to the rotator cuff, the complex of tendons and muscles that provide stability to the shoulder. Tears may occur in any one of the tendons that connect the three large muscles: the supraspinatus, the intraspinatus, and the subscapularis. Gradually, techniques and instrumentation were developed that allow for all aspects of the repair to be done with arthroscopy alone or with a small incision ("mini-open" procedures).
Rotator cuff surgery may involve a number of steps, including debridement or removal of any loose tissue fragments in the area. The acromion may require smoothing or a portion of the bones forming the acromio-clavicular (AC) joint may need to be removed. If it is inflamed, a bursa (a fluid-filled sac that provides cushioning in the joint) may also be removed (bursectomy). Finally, the loose portion of the tendon is sutured and anchored to the humerus. (If the cuff is badly damaged, the patient may require rotator cuff reconstruction with a tendon obtained from elsewhere in the body or allograft.)
Additional Shoulder Conditions
Other conditions in the shoulder that may be diagnosed and treated with the help of arthroscopy include:
- Impingement: a condition in which the rotator cuff tendon becomes inflamed or abraded. Treatment may involve shaving off a portion of the overlying acromion that may be causing the problem. A bursectomy may also be needed.
- Calcium deposits in the rotator cuff which can cause pain and stiffness; excision can provide relief.
- Injury to the acromioclavicular joint.
- Shoulder instability and procedures to stabilize the joint. The labrum if torn will require arthroscopic repair.
- Frayed biceps tendon, conditions that are treated with debridement, a smoothing of rough surfaces and removal of loose tissue or biceps tendosis.
- Articular cartilage injuries, and, where appropriate, use of articular cartilage regeneration techniques (For more information on cartilage regeneration, please see the link under Further Reading at the conclusion of this article.)
- Frozen shoulder, a condition of unknown origin in which the patient develops synovitis and subsequent contracture resulting in a very limited range of motion. In order to restore mobility, the orthopaedic surgeon makes small cuts in the tissue, releasing the contractures that are present.
- Arthritis of the shoulder: debridement of cartilage and loose bodies can provide symptom relief for a variable period of time.
- As a complement to open treatment of fractures. In this setting, arthroscopy allows the orthopedic surgeon to see otherwise difficult to visualize areas without disrupting the joint and perform a pinning of the fracture fragment or in conjunction with a percutaneous pinning.
Shoulder impingement syndrome involves one or a combination of problems, including inflammation of the lubricating sac (bursa) located just over the rotator cuff, a condition called bursitis; inflammation of the rotator cuff tendons, called tendinitis; and calcium deposits in tendons caused by wear and tear or injury. A torn rotator cuff is a potential outcome of shoulder impingement.
Bursitis: Frequent extension of the arm at high speed under high load (i.e., pitching a baseball) can cause bursitis. Nonsports activities such as painting, hanging wallpaper or drapes or washing windows also can cause it. Medical research shows that the older you get, the more likely you are to develop bursitis.
Tendinitis develops over time and is likely to occur when a person whose muscles are not in good condition starts an overly aggressive training program. In younger athletes, the causes of tendinitis are similar to those of bursitis.
What are the signs and symptoms?
Patients frequently try to ignore the first signs of shoulder problems. There is usually no single episode of the shoulder giving way and, at first, a person may notice only minor pain and a slight loss of strength. Loss of range of motion, especially the ability to lift the arm overhead, may be ignored for awhile.
Bursitis: Symptoms of shoulder bursitis include mild to severe pain and limited movement.
Tendinitis: Inability to hold the arm in certain positions indicates tendinitis is present. Recurrent episodes of tendinitis may indicate a rotator cuff tear.
What is initial treatment?
Bursitis: Once bursitis is diagnosed, rest is the recommended treatment. If necessary, icepacks can also be prescribed, as well as anti-inflammatory drugs, steroid injections and ultrasound therapy. Some patients require temporary use of a sling. After inflammation subsides, the patient should do shoulder strengthening exercises.
Tendinitis: Acute tendinitis usually passes if the activity which caused it is avoided long enough to give the shoulder sufficient rest. Later, a patient can gradually resume the activity incorporating gentle heat and prescribed stretching beforehand and icepacks afterward. More severe cases may require anti-inflammatory drugs or a cortisone injection.
If initial treatment doesn't work, what's next?
Bursitis: Severe bursitis can require surgery.
Tendinitis: A physician may perform additional diagnostic tests to rule out other conditions before surgery is advised.
How can further injury be prevented?
Overuse injuries require attention. However in many cases, people do not seek medical care for their shoulder inflammation and think they can "work through the pain." Don't play tennis or golf in an attempt to "loosen up" tightness. When a shoulder injury is ignored, it can become the source of chronic problems. If your shoulder is sore after you use it actively, especially at the limits of your reach, give it some rest. If pain persists or worsens, consult your orthopedist.