Knee Replacement Long-Term Expectations: A Comprehensive Guide

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A total knee replacement, also known as TKR or Total Knee Arthroplasty, is a medical procedure that is used to reduce knee pain and improve your activity levels.^[13] TKR is a highly successful and frequently performed surgical intervention. The procedure is capable of successfully improving health-related quality of life soon after the surgery is complete, with some physical therapy milestones being achieved already within the first 7-14 days after surgery.^[5] However, what can you expect multiple years after surgery? This blog focuses on the intermediate and long-term quality of life after total knee replacement. As with any medical procedure, TKR can present both long-term risks and benefits. Considering the long-term outcomes of total knee replacement can provide you with better insight into whether total knee replacement is right for you. This blog is split into what you can expect at 1, 5, 10, 15, and 20 years after a total knee replacement.

Alternatively, if you are interested in what to expect after surgery in the short term, check out our blog on what to expect right after a knee replacement.

Measuring Long-term Outcomes Following Total Knee Replacement

To evaluate long-term outcomes after TKR, studies consider quality of life after surgery and factors such as sex, age, obesity, location of the surgical site, social support, and number of comorbidities, which is the simultaneous presence of more than one medical condition within a person. Unilateral or bilateral replacement, meaning if the replacement is completed on one or both knees, is also considered when determining quality of life after TKR.^[5] Various research studies that are mentioned within this blog measure and evaluate quality of life after TKR using different methods. This includes self-reported outcome indexes, scores, or questionnaires such as the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Society Scores (KSS), and SF-36. The WOMAC is widely used in the evaluation of hip and knee osteoarthritis.^[1] The Knee Society Score (KSS) considers factors such as pain intensity, range of motion and stability in various planes of motion, flexion deformities, contractures and poor alignment.^[2] The SF-36 stands for Short Form 36 Health Survey, which is a patient-reported survey that measures physical functioning and ability, bodily pain, general health, vitality, social functioning, and mental health using a scale ranging from 0-100. Higher scores indicate better quality of life.^[11] The 0-100 scoring system is also applied within the Knee Injury and Osteoarthritis Outcome Score (KOOS), which is another patient-reported outcome measure used after knee and hip replacement.^[23] To learn more about the KOOS, check out our blog on what does my knee injury and osteoarthritis score or KOOS mean?

Overall, these measures help identify statistically significant changes in aspects such as knee pain, knee function, and overall physical and mental health from before to after total knee replacement. This makes it easier to understand the long term life experience of people after the TKR.^[25] How do these measures allow me to understand my knee replacement recovery? It is critical to ask people how they are doing after surgery using patient reported outcome measures because it can help you understand what can be expected after surgery. Another important thing that this blog does is it allows people to understand the long term outcomes after a knee replacement.

1 Year After Knee Replacement

Within the first year of your knee replacement, the most notable improvements in physical functioning and reduction in bodily pain take place. In a study by Fitzgerald and colleagues, people over 50 years old who had a total knee replacement to treat their osteoarthritis were examined 1 year after their surgery. People experienced significant improvements in physical function and bodily pain after surgery.^[5] However, a plateau in bodily pain improvements occured at 6-months after knee replacement, meaning that further reduction to pain may be limited after this time. This suggests that people may still experience some persisting pain 1 year after surgery. Living with someone after knee replacement can help reduce subjective reports of bodily pain.^[5] This reiterates that the support you have available from your friends, partner and family in the recovery process, especially in the first year after your knee replacement, plays an important role in improving your quality of life after surgery.

In terms of physical activity, many people can return to a full range of activities 1 year after knee replacement. According to Thaler and colleagues, with the exception of squash, which should be completely avoided according to these authors, after 12 weeks, stair climbing, swimming, aqua fitness, cycling (static and outside), yoga, tennis, golf, fitness and weight lifting, aerobics, hiking, nordic walking, and sailing are all activities that are allowed.^[26] Check out our blog to learn more about what sports and exercises you can do after a total knee replacement.

While the number of sport events people participate in may decrease after knee replacement, people reported enhanced performance of sport and recreational activities 1 year after knee replacement.^[20]^[10] Factors such as sex can also influence physical activity engagement after knee replacement, as men are more likely to return to activity than women.^[10]

According to Chatterji and colleagues, golf was the only sport that had a significant reduction in participation 1 year after knee replacement, with 53% of people who engaged in golf giving up the sport completely after their knee replacement.^[20] On the other hand, 13.2% of people who were unable to walk before having a knee replacement started engaging in walking 1 year after having surgery. Some people even noted starting a new activity, such as aqua aerobics, 1 year after their knee replacement. Despite such evidence of return to sports after a knee replacement, there is increased participation in lower impact activities such as walking, hiking, cycling, and swimming, and a decrease in participation in high-impact activities such as jogging, skiing, or tennis.^[20]

5 Years After Knee Replacement

While bodily pain reduction has been suggested to stop within the first year after knee replacement, improvements in physical function can be seen even 5 years after surgery.^[8]^[4] According to a study by Cushnaghan and colleagues, which evaluated outcomes 5 years after a knee replacement using the SF-36, people reported a significant improvement of 6 points in physical function score. People who did not undergo knee replacement reported a significant reduction of 14 points. This significantly larger improvement was also reported in people who were obese compared to those who were not obese.^[4] This suggests that improvements in physical function can take place after knee replacement regardless of body weight. On the other hand, if you choose not to undergo a knee replacement to treat your knee osteoarthritis, this study suggests you may experience hindrances in physical function, making you less likely to take part in physical activities that you were once involved in due to pain, limited range of motion,^[24] or knee instability.^[28]

In terms of physical activity, in a study by Bradbury and colleagues, 77% of people returned to sport 5 years after their knee replacement.^[3] Once again, it is important to note that people are more likely to return to low-impact activities such as bowling than high-impact activities such as tennis.^[20] Despite this trend, there is limited evidence on the link between high-level sports and complications after knee replacement surgery such as the knee implant loosening or need for a premature revision surgery.^[20] For example, Bradbury and colleagues identify that 33% of their study participants, who were 73 years old at 5-year follow up after their knee replacement, participated in high impact sports without implant failure.^[3] There is even a study that suggests that high-level tennis players were able to return to tennis 5 years after a knee replacement.^[15] These study findings reiterate that while there may be risk to participating in certain activities after surgery, returning to sport 5 years after a knee replacement is specific to the individual, their physical activity background, and their age. The intention of this blog is not to give return to sport advice and this is a conversation that you should have with your orthopaedic surgeon and or your physical therapist.

10 Years After Knee Replacement

Even 10 years after knee replacement, people can experience enhanced well being and positive physical capacity, such as being able to walk without limitations.^[21]^[27] However, you may still experience not being able to participate in high-impact activities such as running. For example, in a Finnish study examining women 10 years after their knee replacement, 41% reported maintaining or improving their subjective well-being 10 years after surgery.^[27] Furthermore, 80% of women reported having a good physical capability. Good physical capability is characterized by walking independently without limitations, for a distance of more than 1000 meters, and both indoors and outdoors. However, while no other limitations were reported, good physical capacity was also characterized by not being able to run.^[27]

As more time passes after surgery, improvements to quality of life may be more limited.^[18]^[21] A study followed up with 89 people who were 73 years old 10 years after their total knee replacement. In comparison to people with the same age who did not have a total knee replacement surgery, the people who had a TKR reported lower quality of life. They experienced limitations with physical activities, self care, and housekeeping tasks.^[21] They also reported more comorbidities and sites of bodily pain unrelated to their TKR surgical site, which has contributed to their lower quality of life.^[21] Remember that engaging in exercise before knee replacement can contribute to improving your quality of life after surgery.^[16]

Total Knee Replacement Article

15 years after Knee Replacement

At 15 year follow-up, knee function was better in younger patients than older patients.^[6]^[17]^[9] According to Lizaur-Utrilla and colleagues, primary total knee replacement can provide successful pain relief, function, and quality of life in people with osteoarthirtis. Knee replacement can significantly increase survival in older people and women in particular.^[22] Also, older people, females, and people who still had their primary replacement report the least pain at 15 years after surgery.^[22] This suggests that your long-term quality of life 15 years after a knee replacement can be affected by your age and sex.

20 years after Knee Replacement

A knee replacement can help maintain physical functioning and activity even 20 years after surgery.^[14]^[27] Statistics show that 53% of females identified having good physical capability, which is characterized by walking without limitations.^[27] This means that even 20 years after a knee replacement, a person is more likely than not to engage in independent walking successfully. However, despite reports of good physical capability, walking was not completely restored 20 years after a knee replacement. Also, reports of physical capability and subjective well-being tend to decrease 20 years after surgery. Therefore, as more time passes after a knee replacement, people who had the surgery may experience more physical limitations and less satisfaction. Younger people may also be less satisfied with their knee replacement surgery.^[19] This is because younger people may be more critical of their movement capacity years after surgery, reporting more persistent symptoms of stiffness, swelling, and pain in or around the knee joint after surgery.^[27]

Conclusion

Knee replacement is a highly successful and frequently performed surgical intervention used to treat knee osteoarthritis. The procedure is capable of successfully providing pain relief and improved physical function long-term, overall contributing to enhancing quality of life for people who previously struggled with osteoarthritis.

At 1 year after surgery, people experienced significant improvements in physical function and bodily pain after surgery.^[5] However, 6 months after knee replacement, further pain reduction may be limited. Living with someone after a knee replacement can help reduce subjective reports of bodily pain.^[5] In terms of physical activity, people can return to a full range of activities 1 year after surgery, including stair climbing, swimming, aqua fitness, cycling (static and outside), yoga, tennis, golf, fitness and weight lifting, aerobics, hiking, nordic walking, and sailing. Squash, however, should be avoided. At 5 years you can also expect improvements in physical function and a return to sports.^[3] During this time, it is important to note that people were more likely to engage in low-impact activities such as bowling than high-impact activities such as tennis.^[20] At 10 years you can continue to experience enhanced well-being and positive physical capacity, such as being able to walk without limitations.^[21]^[27] You may still experience not being able to participate in high-impact activities such as running. Your long-term quality of life after a knee replacement can be affected by your age and sex. For example, 15 years after surgery, people younger than 55 experienced better knee function than people over 55.^[12] In terms of pain, older patients, females, and people who still had their primary replacement in place at 15 years reported the least pain.^[12] At 20 years after surgery, a person can continue to maintain physical functioning and activity levels; however, older people may benefit more from a knee replacement than younger people.^[14]^[27] Walking may not be completely restored 20 years after a knee replacement.

Curovate has a recovery plan specifically for Total Knee Replacement. This plan helps you to stay on track with your recovery by using video-guided exercises, reminders, and the ability to measure your knee bending and straightening (called range of motion). Your exercises will gradually get harder as you begin to regain your knee movements and strength, helping you to recover over time using our physical therapy app, Curovate.

To try the app today, click the download links below. If you’re wondering what to expect after your surgery, you can read our blog on 6 Things You Need to Know After a Total Knee Replacement.

If you need further customized assistance during your knee replacement recovery, check out our Virtual Physical Therapy page to book your 1-on-1 video session with a physical therapist.