HC Chang Orthopaedic Surgery | Singapore

Knee Osteoarthritis – Should I Go for a TKR (Total Knee Replacement)?

Knee Osteoarthritis – It is a painful condition of the knee joint where the smooth lining (articular cartilage) of the ends of the thigh bone and shin bone forming the knee joint becomes worn out or rough.

It causes stiffness, pain, swelling and deformity of the knee joint.

Non-Surgery Treatments

• Weight loss (loss of 5kg can result in noticeable improvement in knee pain symptoms from osteoarthritis).
• Use of walking stick or cane.
• Pain killers – such as Panadol, Tramadol etc.
• Non-Steroidal Anti-inflammatory Medications (NSAIDS). These are powerful medications that can significantly reduce the knee pain, stiffness and swelling from knee osteoarthritis. However, it has serious side effects such as peptic ulcer disease or even kidney impairment to kidney failure if taken for excessive length of time.
• Physiotherapy. Exercises to improve the strength of the muscles around the knee joint can help.
• Injections to the Knee. Use of lubricant injections to the knee can help reduce pain symptoms. These are viscosupplements but the effectiveness is not always guaranteed and the cost of these treatments can be quite hefty.
• TCM, Traditional Chinese Medicine treatments include acupuncture and moxibustion. These modalities can sometimes bring about some symptomatic relief.

None of the above treatments actually reverse or remove the underlying problem of cartilage loss. The effectiveness of these treatments can wane when the disease process becomes more serious over time.

Total Knee Replacement

A total knee replacement is an established and standard surgical procedure to treat knee osteoarthritis pain.

The diseased portion of the knee joint is removed and the ends of the thigh and shin bones replaced with metal prosthesis and a plastic insert is placed between the 2 metal prosthesis.

The pain from the knee osteoarthritis disappears almost immediately after the surgery.

There are potential complications from this surgery. These include:

• Infection. Infection can result in need for multiple repeat surgeries to that knee including removal of the metal prosthesis. In very rare cases, the patient’s leg may need to be amputated if the infection cannot be brought under control.
• Blood clots in the leg and the associated complications. Deep vein thrombosis (DVT) can occur in patients who undergo total knee replacements. Some surgeons routinely put their patients on blood thinners post-surgery to reduce this risk. Pulmonary embolism occurs when the clot in the leg veins dislodges and moves to the blood vessels of the lungs. This can be a potentially fatal complication.

A Dilemma

A person with painful knee from knee osteoarthritis have to consider all these factors and it may be daunting for the patient to make a decision on whether to go for surgery or not.

Evidence

A recent research published in the New England Journal of Medicine looked at people with knee osteoarthritis who were divided randomly into 2 treatment groups of either conservative treatment versus total knee replacement treatment showed that the results in the total knee replacement group were better than the group treated without surgery.

A Randomized, Controlled Trial of Total Knee Replacement. Søren T. Skou, P.T., Ph.D., Ewa M. Roos, P.T., Ph.D., Mogens B. Laursen, M.D., Ph.D., Michael S. Rathleff, P.T., Ph.D., Lars Arendt-Nielsen, Ph.D., D.M.Sc., Ole Simonsen, M.D., D.M.Sc., and Sten Rasmussen, M.D., Ph.D. N Engl J Med 2015; 373:1597-1606.

In this randomized, controlled trial, the authors studied 100 patients with moderate-to-severe knee osteoarthritis who were eligible for unilateral total knee replacement. Patients were randomly assigned to undergo total knee replacement followed by 12 weeks of nonsurgical treatment (total-knee-replacement group) or to receive only the 12 weeks of nonsurgical treatment (nonsurgical-treatment group), which was delivered by physiotherapists and dietitians and consisted of exercise, education, dietary advice, use of insoles, and pain medication. The primary outcome was the change from baseline to 12 months in the mean score on four Knee Injury and Osteoarthritis Outcome Score subscales, covering pain, symptoms, activities of daily living, and quality of life (KOOS4); scores range from 0 (worst) to 100 (best).

Findings

A total of 95 patients completed the 12-month follow-up assessment.

In the nonsurgical-treatment group, 13 patients (26%) underwent total knee replacement before the 12-month follow-up; in the total-knee-replacement group, 1 patient (2%) received only nonsurgical treatment.

In the intention-to-treat analysis, the total-knee-replacement group had greater improvement in the KOOS4 score than did the nonsurgical-treatment group (32.5 vs. 16.0; adjusted mean difference, 15.8 [95% confidence interval, 10.0 to 21.5]).

The total-knee-replacement group had a higher number of serious adverse events than did the nonsurgical-treatment group (24 vs. 6, P=0.005).

Conclusions

In patients with knee osteoarthritis who were eligible for unilateral total knee replacement, treatment with total knee replacement followed by nonsurgical treatment resulted in greater pain relief and functional improvement after 12 months than did nonsurgical treatment alone.

However, total knee replacement was associated with a higher number of serious adverse events than was nonsurgical treatment, and most patients who were assigned to receive nonsurgical treatment alone did not undergo total knee replacement before the 12-month follow-up.

To Explain in a Simple Way, Please Watch This Cartoon:

For more information on Total Knee Replacement Surgery, please contact Dr HC Chang at +65-683 666 36 or email him at hcchang@ortho.com.sg