What's New in Treatment for Younger Adults with Shoulder Arthritis

Osteoarthritis of the shoulder isn't always something older people experience. Sometimes younger adults (ages 20 to 50) develop pain, stiffness, and loss of motion and function from arthritic changes in the joint. Although the effects are the same, the causes often differ between young and old. Older adults tend to develop arthritis as a result of aging and joint degeneration from many, many years of use.

Younger adults are more likely to have had an injury earlier in life that has now resulted in trauma-induced arthritis. Infections, repetitive motions that cause microtrauma, and chondrolysis following arthroscopic shoulder surgery are other reasons why the joint cartilage wears away and arthritis sets in. Chondrolysis is the medical term for destruction of articular cartilage. That's the cartilage that lines the joints and makes smooth motion possible.

No one is quite sure why chondrolysis develops in some people after arthroscopic procedures. It happens after all kinds of arthroscopic operations -- not just for one type of problem. It happens in patients who have had thermal devices, suture anchors, and pain pumps put in the joint. But not everyone who have those implants develop chondrolysis, so there probably isn't just one single reason for this rapid destruction of the joint cartilage.

What can be done for the person with early onset of shoulder arthritis? Some time ago, artificial shoulder joint replacements were made available to younger patients with arthritis. But enough time has passed that we now know from short- to mid-range follow-up studies that this isn't always the perfect solution. The implant can wear out or loosen. Then it has to be replaced. That can mean a second surgery, loss of bone, further complications, and a major set back in motion and function.

Likewise, for hemiarthroplasties (replacing just one side of the joint), the side that isn't replaced eventually wears out, too. Or the side with the replacement implant develops problems with loosening or biomechanical wear and tear. That means more surgery for those patients as well. What's the answer to this dilemma? The evidence supports delaying joint replacement by pursuing conservative (nonoperative) care for as long as possible.

Okay, so, what works in that department? Patients have a few choices. Physical therapy to build up strength around the shoulder and minimize stress or overload on the joint is one approach. Acupuncture, transcutaneous nerve stimulation (TNS), and nonsteroidal antiinflammatories (NSAIDs) may be helpful. Like any medication, NSAIDs have the potential to create adverse reactions. The physician and the patient must weigh the benefits against the potential side effects when choosing these drugs. They may reduce painful inflammation and improve movement, but they can cause significant gastrointestinal (GI) complications and therefore, must be taken with another drug to protect the GI tract.

Injections of a visco-supplement or steroid may provide some relief of pain compared with placebo (pretend injections of just saline, a salt solution). The visco-supplement is a fluid that helps restore pain free movement in the joint. It has been shown to be more effective and longer lasting than the steroid injections with fewer side effects. Steroid injections reduce inflammation and usually have a numbing agent included that helps reduce pain. There aren't very many studies of results from these two different types of injections. More information is needed about the short-term and long-term effects of both before shoulder injections can be routinely recommended.

When surgery is needed, it's best to start with noninvasive (or the least invasive) procedures possible. Every effort should be made to stimulate a healing response and save the joint, rather than remove and replace it. Joint sparing is the name given this approach. There are several ways to do this. The first (and most commonly used) procedure is called debridement. The joint is shaved and smoothed down. Any debris or loose fragments of cartilage are removed. This helps restore smooth, pain free motion.

There are also various ways to repair and/or restore damaged cartilage. For example, autologous chondrocyte implantation (ACI) and osteochondral autologous transplant (OATS) are two restorative procedures. In these procedures, cartilage is placed inside the lesion in hopes of restoring the normal structure and function of the original cartilage. ACI is a new way to help restore the structural makeup of the articular cartilage. Surgeons may recommend this procedure for active, younger patients (20 to 50 years old) when the bone under the lesion hasn't been badly damaged, and when the size of the lesion is small (less than four centimeters in diameter).

ACI is done in two parts. First, a short surgery is scheduled to allow the surgeon to take a few normal, healthy chondrocytes and use them to grow more in a laboratory. At a later date, the patient returns for a second surgery, at which time the surgeon implants the newly grown cartilage into the lesion and covers it with a small flap of tissue. The cover holds the cells in place while they attach themselves to the surrounding cartilage and begin to heal.

With the second restorative procedure, OATS, a plug of cartilage and the first layer of (subchondral) bone are removed from normal, healthy cartilage and transferred to the site of the cartilage defect. This can be done all in one procedure and does not require two operations like the ACI.

If conservative care and minimally invasive restorative procedures fail to bring the relief patients need, then joint replacement may be the next step. The surgeon assesses the joint surface and surrounding soft tissues to determine which approach is best. The patient's age, activity level, goals, and bone density are all taken into consideration when choosing the best surgical approach for each patient. Hemiarthroplasty works well for younger patients but the benefits are only short- to mid-term. In the end, these patients often develop pain from continued degeneration of the joint and require a total joint replacement. But the hemiarthroplasty might buy them some time and allow them to function pain free for several years.

Some surgeons have tried using a hemiarthroplasty (replacing the head of the humerus) while resurfacing the socket side of the joint called the glenoid. Resurfacing means lining the glenoid with cartilage, ligament, or connective tissue harvested from some other part of the body. The results of studies so far haven't been spectacular with this approach. So far there have just been too many problems and complications with resurfacing. More studies are needed to improve outcomes with this technique.

The most invasive approach is a total shoulder arthroplasty (also known as a total shoulder replacement or TSH). Patients seem to respond well to this procedure. They get significant pain relief, which then allows them to move freely and to be more active. Most implants (99 per cent) hold up well the first five years. There are good short and mid-term results reported; long-term wear eventually results in loosening and wear of the glenoid.

Young patients with shoulder arthritis really do have quite a few options to choose from for the treatment of this potentially disabling condition. Conservative care and joint sparing are the order of the day. Restorative procedures for damaged cartilage may be all that's needed. But when symptoms continue to reduce what the patient can do on a daily basis, then a partial or complete joint replacement might be best. Given what we know about problems from these procedures, patients should be advised of all the pros and cons before deciding on the management approach that suits them best.



References: Jesse A. McCarron, MD. Shoulder Arthritis and the Young Patient. In Current Orthopaedic Practice. July/August 2009. Vol. 20. No. 4. Pp. 382-387.