You've been active all your life, maybe even played some sports in years past. Your knees may have given you some trouble from time to time … but now that trouble is becoming more noticeable, more frequent and the pain is lingering longer.

Parking closer to the entrance of the local mall or supermarket is now becoming a necessity. The anti-inflammatory medicines and exercises have worked for a while, but now you're finding it harder to climb stairs or even get up from a chair. You've seen your orthopedic surgeon who, after taking X-rays, tells you that you have osteoarthritis.

Millions of Americans suffer from osteoarthritis of the knee, a condition where the cartilage in the knee joint deteriorates and the unprotected bone underneath begins to wear away, resulting in pain.

Until recently, the surgical options were limited to arthroscopic knee surgery and a total knee replacement.

However, an additional option has recently become available here in the Hudson Valley. It's called a unicondylar (or partial) knee replacement.

Arthroscopic surgery is a minimally invasive procedure to remove debris or repair torn cartilage. It can be considered for patients with mild arthritis as a way to delay the need for knee replacement surgery.

Total knee replacement surgery is major surgery that replaces all three compartments of the knee.

Between those two alternatives now lies the unicondylar knee replacement. This procedure is a minimally invasive option for patients with knee arthritis that is isolated to one area of the knee. Only the area damaged by arthritis is replaced, preserving normal bone and cartilage.

There are many benefits to unicondylar knee replacement. The procedure can often be performed through an incision that is less than three inches in length, compared to an eight-inch incision often required for total knee replacement.

As a result, there is minimal blood loss, less post-op pain and a greatly reduced period of hospitalization. There is also a reduced need for anesthesia and post-operative medication.

After the surgery, these patients experience a much faster rehabilitation and recovery. In total knee replacement, recovery is usually three to six months compared to four to six weeks for unicondylar replacement.

It's also a good alternative for the younger patient. Because total knee replacement can be expected to last only 10 to 15 years, many orthopedic surgeons have been reluctant to offer it to younger patients.

Research shows that a unicondylar knee is easily revised to a total knee replacement down the road, leading to excellent long-term results.

As with any surgery, there are potential risks involved. Only your orthopedic surgeon can determine if you are a candidate. It is typically considered in patients who have osteoarthritis limited to one compartment of the knee, are greater than 45 year of age and have pain despite nonsurgical treatment such as the use of anti-inflammatory medication and physical therapy.