Constructive Surgery of the Knee
Robert H. Malstrom, M.D., November, 2003
Knee injuries are among the most common and painful of health problems. More than 2 million people experience knee injuries in the U. S. each year. There has been a 50% increase in knee injuries among people 65 and older in the past ten years. More than 5 million people see an orthopedic surgeon for knee related problems annually. Of these problems, 3 million are caused by accidents, the remainder is related to arthritis or other degenerative disorders.
Knee injuries are a growing problem for women. High school and college aged women are five times as likely to sustain serious knee injuries as young men involved in the same activities. More than 10,000 women in college and 20,000 women in high school will experience knee injuries this year.
Knee problems not associated with arthritis are most commonly caused by repetitive motion, wear and tear, exercise or athletic activities. Accidents also are a frequent cause of knee problems involving auto collisions and workplace mishaps. Knee injuries are also the most common form of injuries in downhill skiing and occur frequently in many other sports including basketball, soccer and football.
Treatment of knee injuries and conditions routinely includes rest, analgesics, physical therapy and sometimes surgery. With the advent of arthroscopic surgical treatment, approximately 20 years ago, our understanding of knee injuries and our ability to treat them has dramatically increased. Unfortunately, until recently, our ability to treat significant degenerative problems of the knee was limited and would result in only short-term improvement. During the past five years, several new treatments have become available. These include:
- Cultured cartilage tissue (Autologous Chondrocyte Implantation)
- Chondral grafting
- Unicompartmental hemiarthroplasty
Prior to the advent of the above treatments, surgical treatment usually was palliative until it was determined that the symptoms and disability were enough to warrant a total knee arthroplasty. By that time, an individual’s ability to participate in activities of normal life as well as in increased activities including recreational or organized sports had become extremely limited.
Autologous Chondrocyte Implantation (ACI) is a procedure which can result in dramatic improvement in knee conditions that would previously have required a total knee arthroplasty. ACI is used to treat damage to the part of the knee formed by the end of the thigh bone, the knee cap or more recently the lower bone, the tibia. In this process, healthy cartilage cells are harvested from the patient’s damaged knee at the time of initial arthroscopy. They are sent to the Genzyme Tissue Repair Laboratory in Cambridge, Massachusetts. Approximately four to five weeks later they are returned and are implanted into the damaged cartilage area. At the time the new cartilage cells are implanted, the surgeon removes damaged and unhealthy cartilage tissue and prepares the area for the introduction of the cultured cells. A small piece of periosteum (a soft tissue covering the bone) is taken from just below the patient’s knee joint and stitched over the damaged area to hold the new cartilage cells in place. The cultured cells are then implanted under this tissue where they continue to multiply and integrate with surrounding cartilage to restore the cartilage surface.
Clinical research results have shown that the treatment produces a durable hyaline cartilage similar to the cartilage found in an undamaged knee in a majority of patients. Many patients are able to resume normal activity within a year after treatment. In addition, many people are also able to regain function to the level they can resume recreational or organized sports. Since the replacement cartilage is derived from the patient’s own cells, there is no danger of rejection by the immune system.
Since the ACI procedure was introduced, more than 3,400 patients have been treated with this procedure by specially trained surgeons around the world. It has been used in the treatment of both male and female patients including a number of children suffering from knee pain or injury.
Robert H. Malstrom, M.D. has had extensive experience with this procedure including performing it in extensively damaged knees which previously could only have been treated with total knee arthroplasty.
Chondral Grafting is a procedure that has also become more widely used in the last five to ten years. Its major indication is for damaged areas which are smaller than what might be considered for the ACI procedure but larger than what could be otherwise treated with historical techniques.
Hemiarthroplasty is a procedure that replaces the inside areas of damage on the upper bone and lower bone on the knee. The outside area and the knee cap are left alone. The advantage of hemiarthroplasty is that in selective individuals that have the inside wear areas most damaged, a replacement of these areas can be performed successfully without the more extensive surgery required of a total knee arthroplasty. Hemiarthroplasty has been performed for over 20 years, however, it has increased success and popularity in the last five years due to improved technology of implant and implant systems.
Total knee arthroplasty has been performed for approximately 25 years. The experience with total knee arthroplasty has been generally very good. It is obviously a procedure which is reserved for knees that cannot otherwise be treated constructively. Surgeons at Tri-Valley Orthopedics and Sports Medical Group have extensive background experience in performing total knee arthroplasties.
The treatment of serious knee problems has evolved dramatically in the last five to ten years. We now have the ability to treat many conditions arthroscopically. Conditions which are more severe may require open surgical treatment including chondral grafting, autologous chondrocyte implantation, hemiarthroplasty or total knee arthroplasty. There are several additional treatments which are currently in development and it is quite likely that these treatments may also develop into proven ways for treating knee conditions which will increase our treatment options and result in greater improvement in function, decrease symptoms and faster return to normal activities.