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How much weight does a knee replacement add to your body?

Knee replacement surgery, also known as knee arthroplasty, is a common procedure performed to alleviate pain and improve mobility in individuals with severe knee joint damage. While the surgery itself provides significant relief and improves the quality of life for many patients, it is important to acknowledge that knee replacement surgery can have implications beyond the surgical outcome. One such consideration is the impact of the surgery on a person’s weight. This blog post aims to explore the relationship between knee replacement surgery and weight gain, as well as provide strategies for managing weight post-surgery.

The impact of knee replacement surgery on weight

It is not uncommon for individuals who undergo knee replacement surgery to experience weight gain in the months and years following the procedure. In fact, studies have shown that a significant percentage of patients gain weight after knee replacement surgery. According to research conducted at the University of Delaware, approximately 66% of individuals in the surgical group gained weight over a two-year period, with an average weight gain of 14 pounds. Furthermore, those who had the knee replacement surgery started out heavier and ended up heavier than the control group.

Factors contributing to weight gain after knee replacement surgery

Several factors can contribute to weight gain following knee replacement surgery. These factors include reduced physical activity levels, changes in mobility and exercise routines, psychological factors such as emotional eating, and the influence of medications.

Reduced physical activity levels: After knee replacement surgery, patients often limit their physical activities to allow for proper healing and recovery. This decreased level of physical activity can result in a decline in calorie expenditure, potentially leading to weight gain.

Changes in mobility and exercise routines: The surgery itself may lead to changes in mobility and exercise routines. Patients may find it challenging to engage in the same level of physical activity they were accustomed to before the surgery, leading to a decrease in calorie burn and potential weight gain.

Psychological factors and emotional eating: Adjusting to life after knee replacement surgery can be emotionally challenging for some individuals. The stress and changes associated with the recovery process may lead to emotional eating as a coping mechanism, resulting in excessive calorie consumption and weight gain.

Medications and their influence on weight: Certain medications commonly prescribed after knee replacement surgery, such as pain medications and corticosteroids, can contribute to weight gain as a side effect. These medications can alter metabolism and increase appetite, making it more difficult to maintain or lose weight.

Health implications of weight gain post-surgery

Weight gain after knee replacement surgery can have several health implications, particularly related to the replaced knee joint, overall joint function, and an increased risk of complications.

Increased stress on the replaced knee joint: Excessive weight gain can place additional stress on the replaced knee joint, potentially leading to increased wear and tear. This additional stress can compromise the lifespan and integrity of the prosthetic joint.

Impact on overall joint function and longevity: Weight gain can reduce the overall function and range of motion of the knee joint. It may limit the ability to perform activities of daily living and hinder the success of the surgery in restoring mobility.

Correlation between weight gain and increased risk of complications: Weight gain after knee replacement surgery has been linked to an increased risk of complications. These complications may include infection, cardiovascular issues, and diabetes. Excessive weight gain can exacerbate existing health conditions and potentially lead to the development of new ones.

Strategies to manage weight after knee replacement surgery

Managing weight after knee replacement surgery is essential for optimizing the surgical outcome, promoting overall health, and reducing the risk of complications. Here are some strategies to consider:

Rehabilitation and physical therapy: Following the guidance of healthcare professionals, participating in rehabilitation programs, and engaging in physical therapy exercises can aid in regaining strength, improving mobility, and promoting weight management. It is crucial to commit to a regular exercise routine that includes low-impact activities to maintain joint health and manage weight.

Dietary considerations: A well-balanced and nutritious diet is important for maintaining a healthy weight. Incorporating a variety of fruits, vegetables, lean proteins, and whole grains can provide essential nutrients while keeping calorie intake in check. Portion control and mindful eating are also essential components of weight management, as they help prevent overeating and promote healthy eating habits.

Psychological support and counseling: Emotional eating can be a challenge for individuals after knee replacement surgery. Seeking psychological support and counseling can aid in addressing emotional eating habits and developing effective coping mechanisms. These professionals can provide guidance and support to help individuals navigate emotional challenges and establish healthier relationships with food.

Regular follow-up with healthcare professionals: Regularly monitoring weight and addressing any concerns with healthcare professionals is critical for managing weight effectively. These professionals can assess the individual’s progress, make necessary adjustments to medication if applicable, and provide guidance tailored to the individual’s specific needs.


While knee replacement surgery can significantly improve the quality of life for individuals suffering from severe knee joint damage, there are potential implications to consider, including weight gain. Understanding the factors that contribute to weight gain and implementing effective strategies for managing weight post-surgery is essential for optimal recovery and long-term well-being. By taking proactive steps, such as engaging in rehabilitation exercises, practicing mindful eating, seeking psychological support, and maintaining regular follow-up with healthcare professionals, individuals can mitigate weight gain and promote overall health and longevity after knee replacement surgery.


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