Preoperative Whole Food Plant-Based Fiber Smoothie for Total Knee Arthroplasty Revision

This study aims to assess the feasibility of a 2-week dietary whole-food smoothie intervention and compare outcomes between two groups: patients that integrated a daily whole food plant-based smoothie into their diet for two weeks prior to surgery, and a control group of revision TKA patients that made no nutritional changes to their diet prior to surgery. The main research questions are:

1. Among patients planned for elective TKA revision surgery, what is the feasibility of a 2-week dietary intervention implemented 2 weeks prior to surgery? \[Outcomes will be compliance, noted barriers and/or facilitators, satisfaction with diet\]
2. Determine if the implementation of a daily whole food plant- based smoothie dietary supplement 2 weeks prior to TKA revision surgery will reduce inflammation -measured in plasma levels of IL-6 and CRP- at POD0, POD1, POD2, POD3, and 6 Weeks Post-operative as compared to 1) baseline (prior to dietary intervention initiation) and 2) control patients who did not make changes in their diet prior to surgery.
3. Determine if the implementation of a daily whole food plant-based smoothie dietary supplement 2 weeks prior to TKA revision surgery will result in quantifiable changes in the gut microbiome composition -measured via fecal samples- as compared to control patients who did not make changes in their diet prior to surgery.
4. Determine if the implementation of a daily whole food plant- based smoothie dietary supplement 2 weeks prior to TKA revision surgery will result in improved immediate postoperative pain -measured through numeric rating scale (NRS) pain scores- and opioid use -measured in morphine milligram equivalents (MME)- as compared to control patients.
5. Compare patient satisfaction and adoption of nutritional behavioral changes in patients implementing a whole food plant-based smoothie 2 weeks prior to TKA revision surgery to patients undergoing the same surgery but did not me pre-surgery dietary changes.

The researcher's primary outcome is measuring feasibility and patient compliance with smoothie consumption. Secondarily, the investigators are interested in measuring if the preoperative smoothie can alter the gut microbiome and decrease systemic inflammation, leading to lowered post-operative pain and opioid use.

This study aims to assess the feasibility of a 2-week dietary whole-food smoothie intervention and compare outcomes between two groups: patients that integrated a daily whole food plant-based smoothie into their diet for two weeks prior to surgery, and a control group of revision TKA patients that made no nutritional changes to their diet prior to surgery. The main research questions are:

1. Among patients planned for elective TKA revision surgery, what is the feasibility of a 2-week dietary intervention implemented 2 weeks prior to surgery? \[Outcomes will be compliance, noted barriers and/or facilitators, satisfaction with diet\]
2. Determine if the implementation of a daily whole food plant- based smoothie dietary supplement 2 weeks prior to TKA revision surgery will reduce inflammation -measured in plasma levels of IL-6 and CRP- at POD0, POD1, POD2, POD3, and 6 Weeks Post-operative as compared to 1) baseline (prior to dietary intervention initiation) and 2) control patients who did not make changes in their diet prior to surgery.
3. Determine if the implementation of a daily whole food plant-based smoothie dietary supplement 2 weeks prior to TKA revision surgery will result in quantifiable changes in the gut microbiome composition -measured via fecal samples- as compared to control patients who did not make changes in their diet prior to surgery.
4. Determine if the implementation of a daily whole food plant- based smoothie dietary supplement 2 weeks prior to TKA revision surgery will result in improved immediate postoperative pain -measured through numeric rating scale (NRS) pain scores- and opioid use -measured in morphine milligram equivalents (MME)- as compared to control patients.
5. Compare patient satisfaction and adoption of nutritional behavioral changes in patients implementing a whole food plant-based smoothie 2 weeks prior to TKA revision surgery to patients undergoing the same surgery but did not me pre-surgery dietary changes.

Participants will be randomly assigned to consume the whole food plant-based smoothie intervention daily for the two weeks leading up to surgery, or to have no preoperative diet intervention (control group).

The researcher's primary outcome is measuring feasibility and patient compliance with smoothie consumption. Secondarily, the investigators are interested in measuring if the preoperative smoothie can alter the gut microbiome and decrease systemic inflammation, leading to lowered post-operative pain and opioid use.

Eligibility Criteria:
Inclusion Criteria:

* Scheduled for revision TKA at HSS with participating surgeons; not as a result of infection or trauma and all components (tibial and femoral) needing replacement
* Age between 40 and 80
* Diagnosed with osteoarthritis
* ASA Class 1 ('normal' healthy patient) or 2 (patient with mild systemic disease and no functional limitations; the diseases the patient has are well controlled)
* Ability to understand written and spoken English
* Willing to complete entire pre-operative and post-operative work up in NYC, main campus site
* Willing to follow a 2-week smoothie supplement, which means willingness to purchase ingredients and currently own/have access to a blender

Exclusion Criteria:

* Age \>80 years or \<40 years
* Revision due to infection or trauma
* ASA class 3 (patient with severe systemic disease that results in functional limitations) or 4 (patient with severe systemic disease that is a constant threat to life)
* Not interested or unable to provide informed consent
* Unstable weight (\>5kg weight change in the past 3 months, documented in Epic) or currently on weight loss drugs such as GLP-1 agonists
* Already participating in a specific diet such as (i.e. low carbohydrate high-fat, Paleo, Mediterranean) and unwilling to supplement their diet with a daily smoothie during this time; (for LIFE study they excluded vegetarian, vegan, paleo, or keto diet specifically) Weight Watchers.
* Active infection, flare-up of seasonal allergies, or physical trauma (all can alter CRP)
* Could not start or stop a medication during the 2-week study period because some medications, such as statins, can alter CRP concentrations (Ridker 2008) BMI \>40 kg/m2
* Food intolerance/allergy/sensitivity to ingredients suggested for smoothies
* History of IBD
* History of bariatric surgery
* History of cancer
* History of thyroid disease
* History of or current drug abuse
* Pregnancy
* Current smoker
* Cardiac implant or pacemaker