Alternatives to knee replacement for early osteoarthritis

Knee re-alignment (osteotomy)

Osteotomy literally means "cutting of the bone." In a knee osteotomy, either the tibia or femur is cut and then reshaped to relieve pressure on the knee joint.

Knee osteotomy is indicated in early-stage osteoarthritis that has damaged just one side of the knee joint. By shifting the weight off of the damaged side of the joint, an osteotomy can relieve pain and significantly improve function in the arthritic knee.

Osteoarthritis can develop when the bones of the leg do not line up properly. This can put extra stress on either the medial or lateral side of the knee. This extra pressure can wear away the articular cartilage that protects the bones, causing pain and stiffness in the knee.

Successful knee osteotomy surgery should:

• Transfer weight from the arthritic part of the knee to a healthier area
• Correct knee alignment
• Prolong the life span of the patient’s own knee joint

A successful osteotomy may delay the need for a joint replacement for several years. Another advantage is that there are no restrictions on physical activities after an osteotomy – patients will be able to comfortably participate in their favourite activities, even high impact exercise such as football and tennis.

Osteotomy does have disadvantages. For example, pain relief is not as predictable after osteotomy compared with a partial or total knee replacement. It can take slightly longer to recover from an osteotomy procedure than a partial knee replacement.

Because in the past results from total knee replacement and partial knee replacement have been so successful, knee osteotomy surgery had become less common. However it is gaining in popularity as more research is showing good long-term results and more is understood about the importance of preserving the patients own knee.

Osteotomy remains an option for many patients’ especially younger adults with painful osteoarthritis of the knee.

Which patients could benefit from knee osteotomy?

Knee osteotomy is most effective for fit, active patients who are 40 to 60 years old.

The patients should not be smokers.

Good candidates have pain on only one side of the knee, and no pain behind the patella. Knee pain should be brought on mostly by activity, as well as standing for a long period of time.

Patients should be able to fully straighten the knee and bend it at least 90 degrees.

Patients with rheumatoid or inflammatory arthritis are not good candidates for osteotomy.

The operation

A knee osteotomy operation typically lasts between 1 and 2 hours.

The surgeon makes an incision at the side of your knee. They will plan out the correct size of osteotomy using X-rays before the operation. Guide wires are inserted with X-ray guidance to mark out the angle and depth of the osteotomy. With an oscillating saw, the surgeon cuts along the guide wires, and then slowly “opens” up the osteotomy to a pre-determined distance. The surgeon then inserts a plate and screws  (Tomofix ©) to hold the bones in place until the osteotomy heals.

This is the most commonly used osteotomy procedure in the UK, and is called an opening wedge osteotomy.

After Surgery

In most cases, patients stay at the hospital for 1 to 2days after an osteotomy

After the operation, patients may have a knee brace for protection while the bone heals.

The patient will most likely need to use crutches for a few weeks.

About 6 weeks after the operation, X-rays will confirm if the osteotomy is healing and patients can usually begin to return to normal activities over the following months.

Complications

Although the risks are low, the most common complications include:

• Infection
• Blood clots
• Stiffness of the knee joint
• Injuries to vessels and nerves
• Failure of the osteotomy to heal (increased risk in smokers)

Conclusion

Osteotomy can relieve pain and delay the progression of arthritis in the knee. It can allow a younger patient to lead a more active lifestyle for many years. Even though many patients will ultimately require a total knee replacement, an osteotomy can be an effective way to buy time until a replacement is required

References

Ortho info . American academy of Orthopaedic Surgeons