Patients who undergo total knee replacement do not lose weight one year after surgery. A June 2022 study in the journal International orthopaedics (8) followed patients who had a recent total knee replacement to see what effect, if any, the knee replacement had on their weight.
While many overweight patients have the best intentions to lose weight after joint replacement, a study at Hospital for Special Surgery (HSS) finds that although some are able to achieve this goal, equal numbers of patients actually gain weight after hip or knee replacement.
Causes of Weight Loss Post-Op
Some pain management drugs can cause a loss of appetite in certain patients, which can make it difficult to keep your weight at healthy levels post-op. The lingering effects of anesthesia can also cause loss of appetite, as well as nausea and vomiting.
Any extra water being held in the body is referred to as “water weight.” When water builds up in the body, it can cause bloating and puffiness, especially in the abdomen, legs, and arms. Water levels can make a person's weight fluctuate by as much as 2 to 4 pounds in a single day.
Patients who underwent TKA did not obtain a significant reduction of BMI after the surgical procedure. Of these, 46% lost and 54% gained weight in the postoperative period.
To avoid gaining weight, concentrate on lean or low-fat protein sources such as skin-less white-meat poultry, lean cuts of beef or pork, fish, eggs, low fat dairy products, nuts, beans and legumes. Baked, broiled, steamed, roasted and grilled meats are preferred over frying or sauteing to avoid excess calorie intake.
The new knee joint is on average 0.6 lbs heavier than the natural joint. This may be a reason that people feel that their new knee is heavier, and this may contribute to perceptions of an unnatural knee joint.
Timeline of Weight Loss
In the first 6 to 8 weeks after surgery, most patients (regardless of their procedure) will lose ~10% of their excess weight. In the following 4 to 5 months, they can expect to lose a total of ~50% of their excess weight.
Low-impact exercise is the best way to burn calories and protect the healing knee. Try building strength by swimming, rowing, and taking long walks a few days a week, gradually increasing activity over time.
Swelling and bruising at the surgical site is normal. Sometimes bruising will travel up or down the leg. Among what to expect after knee replacement surgery, you should know that blood thinners are often given to decrease the risk of blood clots.
For most people, knee replacement provides pain relief, improved mobility and a better quality of life. Most knee replacements can be expected to last at least 15 to 20 years. After recovery, you can engage in various low-impact activities, such as walking, swimming, golfing or biking.
It's completely normal to have a loss of appetite for the first few days after your surgery.
Energy of healing
Physical therapy and exercise after surgery may push your physical activity farther than it was before surgery. For all of these reasons, you may feel more tired than normal after surgery as your body is using energy for the healing process.
Most orthopedic surgeons and physical therapists recommend exercising for at least 20 to 30 minutes daily, whether it's walking or stretching.
Can I squat or kneel? Half squats for exercise are acceptable. Deep squatting is neither usually possible nor desirable after a knee replacement.
After knee replacement surgery, you can gradually resume normal activities and there are no permanent restrictions, as long as you stay within your comfort level and follow the guidance of your healthcare team.
All too many people who suffer from knee pain find themselves trapped in a vicious cycle of being unable to exercise due to knee pain, which can lead to weight gain that inevitably leads to even more knee pain.
Walking. Walking is a low-impact activity that doesn't put too much stress on your knees and can help strengthen the muscles in that area. Start slow and try to work up to a half-hour walk three to five times a week.
There are a wide variety of adaptive sports you can try that will help with weight maintenance. You can seek out intense sports such as wheelchair rugby, basketball, or tennis, or you can keep it a little more mellow with, say, a leisurely spin on a hand cycle or a round of golf.