BY DR. JOSEPH ZIMMERMAN
Over 54 million people in the United States have arthritis. The symptoms of arthritis can range from mild aches to debilitating pain. More and more, patients and their doctors are turning to joint replacement surgery to help treat severe symptoms of arthritis. The most common joint replacement procedures include knee and hip replacements, with shoulder replacement steadily on the rise. In fact, over 1 million joint replacement surgeries are performed annually in the US, and that number is rising exponentially. As the number of replacements increases, the patient population looking to them for relief is getting younger. Research suggests that joint replacement implants will last an average of 20 years, with a likelihood of earlier wear for younger and more active patients. Revision cases for failed joint replacements exceed 300,000 annually. This leaves many patients wondering if traditional joint replacement is right for them.
In an era of increased focus on fitness and staying active well into our golden years, there has never been a better time to consider alternatives to traditional joint replacement. Joint preservation procedures including partial replacements and resurfacing techniques can provide patients with the pain relief they need while allowing them to return to the active lifestyle they desire.
With a focus on preserving and restoring the normal anatomy of the joint, partial replacements and resurfacing techniques minimize bone loss through minimally invasive techniques, and preserve options if other procedures are needed down the line. These types of procedures are quickly becoming popular for many joints in the body, with proven results in the knee and shoulder paving the way.
In the knee, these procedures are far from new. With over 35 years of clinical data, partial knee replacements have proven to be an excellent option for the right candidates. What has changed is who we believe may be a candidate for a partial knee replacement. In 1989, experts in joint replacement surgery reported that only 5% of patients were candidates for partial knee replacement surgery. Through continual research and advancement in technology, we now consider up to 48% of patients to be eligible for such procedures.
From a joint replacement perspective, the knee is broken down into three compartments: medial, lateral, and patellofemoral. When arthritis primarily affects one compartment of the knee, that patient may be a candidate for partial knee replacement. This leaves the remainder of the knee intact, including bone, cartilage, and ligaments. With more of the native knee intact, and the patient’s normal anatomy preserved, this often results in a knee that feels more “normal”, and leads to a quicker recovery. With a knee that feels more normal, partial knee replacement patients are 2.7 times more likely to be satisfied with the ability to perform activities of daily living than total knee replacement patients. 98% of partial knee replacement patients return to work, and up to 97% were able to return to sports. Partial knee replacement also has a significantly lower postoperative complication rate than total knee replacement (4.3% vs 11%).
Similar advantages exist for resurfacing techniques in the shoulder. Traditional total shoulder replacement is an invasive procedure that significantly alters the patient’s anatomy. Native shoulder anatomy varies widely from patient to patient, and even in the same patient from one side to the other. The shoulder is a ball and socket joint. The socket (glenoid) is relatively shallow, and the ball (humerus) sits on the socket rather than in it. This allows for a tremendous range of motion but also opens the shoulder up to the injuries that can ultimately lead to arthritis. In order to restore the smooth surface of the shoulder, traditional total shoulder replacement removes the ball completely, inserts a stem into the shaft of the humerus, and attaches a new ball. This approximates the size and position of the native ball, but typically doesn’t recreate it perfectly, potentially leading to limitations in range of motion, and too much pressure on the cup. On the cup side, a piece of plastic is attached to the surface of the glenoid. This significantly
changes the position of the joint line and can lead to failure over time. This is known as the “rocking horse phenomenon” because the micro-motion of this implant from everyday activity can cause it to loosen over time. This is of particular concern for younger and more active patients.
Resurfacing techniques of shoulder replacement aim to solve these problems. On the humeral side, the ball is not removed but reshaped and “capped” with a smooth metal surface. This not only matches the size and position of the ball, but implants can more accurately match the shape as well. Research has shown that the humeral head is more of an oval than a circle, and this unique shape plays an important role in joint motion. On the cup side, utilizing a technique that places the plastic component within the glenoid, has minimized the risk of loosening. The glenoid sits flush with the native bone, eliminating the rocking horse phenomenon, and preserving the natural position of the joint line. These minimally invasive, bone-preserving techniques lead to a better range of motion and a more “normal” feeling shoulder.
The benefits of these modern techniques are evident throughout the entire patient experience. Less invasive, lower risk surgeries such as these can often be performed in the outpatient setting, avoiding costly hospital stays and exposure to hospital-acquired infections. Likewise, these procedures often cause less pain and can reduce or eliminate the need for opioid medications. In our current times, these two facts cannot be overemphasized. Whereas traditional techniques place significant restrictions on a patient’s post-operative activity level, resurfacing techniques typically require little to no restrictions. This has opened up shoulder replacement to patients who were often not considered candidates for surgery and left with few options. If conditions or injuries lead to the need for further surgery at any time, these techniques have preserved the patient’s normal anatomy, leaving more options available.
Arthritis can impact patients of all ages. Now more than ever, options are available to treat arthritis and allow patients to return to a fully active lifestyle. If arthritis threatens to put you on the sideline, consult with your doctor to see if one of these options is right for you. Remember, sometimes less is more.
Joseph Zimmerman is a Board Certified, fellowship-trained Surgeon from the Bone and Joint Center in Albany, NY specializing in shoulder and knee surgery including joint preservation procedures. Please call 518-489-2666 to schedule a consultation with Dr. Zimmerman.