Pain following total hip replacement has come a long way over the last 10-15 years with increased use of regional nerve blocks, spinal blocks, and various other modalities used for pain control. Total hip replacement is generally considered to be less painful than total knee replacement.
http://www.aahks.org/care-for-hips-and-knees/do-i-need-a-joint-replacement/total-hip-replacement/
The average hospital stay after knee joint replacement is usually three to five days. The vast majority of people who undergo knee joint replacement surgery have dramatic improvement. This improvement is most notable one month or more after surgery. The pain caused by the damaged joint is relieved when the new gliding surface is constructed during surgery. After knee joint replacement, people are standing and moving the joint the day after surgery.
http://www.webmd.com/osteoarthritis/guide/knee-replacement-surgery
A common reply to this question is that total joint replacement lasts approximately 15-20 years. A more accurate way to think about longevity is via the annual failure rates. Most current data suggests that both hip and knee replacements have an annual failure rate between 0.5-1.0%. This means that if you have your total joint replaced today, you have a 90-95% chance that your joint will last 10 years, and a 80-85% that it will last 20 years. With improvements in technology, these numbers may improve.
http://www.aahks.org/care-for-hips-and-knees/do-i-need-a-joint-replacement/total-hip-replacement/
The general rule of thumb is that knee replacement patients have to avoid certain activities that place a high degree of stress on the knee as much as possible. As long as one refrains from unusually strenuous activities such as running up flights of stairs, their knee replacement should last at least twenty years.
http://www.howlongdoes.com/health/how-long-does-a-knee-replacement-last/
While knee replacements are designed to last a long time, they will not last forever. The good news is that studies show that common types of knee replacements can last more than 20 years. One recent study on long-term outcomes of a commonly used knee replacement found the implant to still be functioning in 96% of patients 20 years after being implanted.
https://www.verywell.com/how-long-do-knee-replacements-last-2549612
Factors Affecting Longevity of Knee Replacements. Many studies have been done to determine how long a knee replacement will last. With hundreds of different types of knee replacements and countless different types of patients, there is no rule to how long a knee replacement will last in a particular individual. Implant manufacturers are constantly striving to create a better implant that will last longer.
https://www.verywell.com/how-long-do-knee-replacements-last-2549612
You and your doctor may consider knee replacement surgery if you have a stiff, painful knee that makes it difficult to perform even the simplest of activities, and other treatments are no longer working. This surgery is generally reserved for people over age 50 who have severe osteoarthritis.
http://www.webmd.com/osteoarthritis/guide/knee-replacement-surgery
As a result, doctors are normally reluctant to give a specific period of time that your knee replacement will last. Having said that, studies suggest that most knee replacements last at least twenty years, and many go on to function smoothly for longer periods of time. There are certain factors that may help increase how long does a knee replacement last.
http://www.howlongdoes.com/health/how-long-does-a-knee-replacement-last/
In general most surgeons prefer that you avoid certain positions of the hip that can increase your risk of dislocation of the hip for about 6 weeks following surgery. After 6 weeks, the soft tissues involved in the surgery have healed, and restrictions are often lifted – allowing more vigorous activity.
http://www.aahks.org/care-for-hips-and-knees/do-i-need-a-joint-replacement/total-hip-replacement/
It is no surprise that the answer to how long does a knee replacement last lies in the weight of the patient. If you want your knee replacement to last and you are currently obese, you should begin to exercise. However, it is important to be careful about which exercises you perform.
http://www.howlongdoes.com/health/how-long-does-a-knee-replacement-last/
how long do most knee replacements last
Most knee replacements last for 20 years. The most knee replacements last for 20 years.